Learjet 24B by Lionheart Creations Ltd.
A review by Ray Marshall
Lionheart Creations recently completed their longest and most ambitious flight simulation project to date. LHC chose one specific model from the now famous Learjet family. The model of choice is a vintage Model 24B that basically rewrote all the speed and altitude records for jet powered aircraft in the mid 1960s. Almost everyone knows about the Lear Jet, but few can actually point one out, and even less know any of the details surrounding the designing, building, testing and marketing of the now famous Learjet family.
Should you have an interest in the circumstances and stories leading up to the first successful pure business jet and the men behind the stories, then read on. If not, and you are only interested in the flight simulation edition then fast-forward to one of the images that catches you attention and start reading at that point. If pressed for time, you can simply move to the end of the review and read the last few pages.
For many people, the name Learjet is a generic term to cover any and all business jets, largely due to the public relations skill of Bill Lear, and James Greenwood, who successfully headed the company's public relations department for many years.
The original Learjet Model 23 took flight 50 years ago and the airplane was a visual sensation in the aviation press, the general news media and most everyone that came into contact with this small and noisy private jet were awestruck. Part of the notoriety came from the flamboyant Bill Lear who promoted the airplane to any and all that would listen. But the Learjet owes much of its mystique to its advanced shape and elegant design.
The sharp pointy nose, the swept-back windscreen and the huge bullet-shaped tip tanks mounted on the razor thin wings all made the Learjet 23 look sleek and fast. The high T-tail, not common in 1964, added to the exotic appearance when compared to the much larger Lockheed JetStar, North American Sabreliner or Hawker Siddeley 125 business jets that were just being introduced to the public. If the bright white paint had been a dull gray, drab olive green or camouflaged I’m sure your first thought would be that you were seeing the future of military aviation.
In 1964 a civilian jet was still very uncommon or maybe non-existent. It had only been about five years since major U.S. airlines put the Boeing 707 and Douglas DC-8 into normal service so the concept of a personal jet was quite radical, but Lear pulled it off.
Lear staked his claim as being the first to produce a pure business jet on the fact that the other three all began life in response to military requirements. Though the JetStar, Sabre and Hawker eventually enjoyed success as civilian business jets, they were all designed to meet a military demand initially.
But the Learjet was really more personal jet than business jet. Lear capped the takeoff weight at 12,500 pounds to keep the Model 23 under the certification rules in what was then called CAR 3, the rules governing small airplanes like those being built by Cessna, Mooney, and Beechcraft down the street. Lear reasoned that by certifying to the same rules that applied to the piston airplanes used for personal and business travel, his Learjet could be flown by a single pilot and not have the same restrictions as the larger transport category jets.
It was a constant struggle, but the first Learjet did weigh-in with enough useful load for pilots, full fuel and a couple of passengers. The cockpit was arranged with key instruments and controls on the left side since a copilot would not be required. And by all accounts the certification authorities gave serious consideration to single pilot approval, but in the end balked and demanded a crew of two.
The Learjet 23 did deliver performance. Not as much as Bill promised, particularly in range, but the airplane quickly earned the nickname Pocket Rocket. Takeoff and landing speeds were pretty high, but the diminutive airplane had so much thrust and so little drag that it accelerated at an astonishing rate. With 5,700 pounds of thrust from its twin GE CJ-610 engines, the Model 23 had only 2.2 pounds of airplane for each pound of thrust at maximum takeoff weight. In typical business jets the thrust to weight ratio was closer to 3.0 pounds of airplane for each pound of takeoff thrust.
With that much thrust the Learjet 23 climbed to and cruised at its certified ceiling of 41,000 feet on even the shortest flights. That got the airplane above all the traffic of the time, but more importantly it quenched the mighty thirst of the turbojet engines that burned more fuel at idle on the ground than a modern turbofan of similar power burns at cruise levels. The CJ-610 was the civilian version of the engines that powered the supersonic T-38 trainer, of the USAF Thunderbirds fame, minus the afterburners.
The Learjet was a productivity tool and a hot rod. It was elegant and it was a rocket. It won over the aviation world and the business community, and captured the public’s imagination. Early buyers were primarily large corporations, but celebrity customers such as entertainers Frank Sinatra and Danny Kaye and newsman Peter Jennings helped foster its image as the ultimate plane for the jet set.
In 1965, the Learjet 23 began setting official performance records. With an engine thrust-to-weight ratio of 1:2.2 pounds, the Learjet could outclimb an F-100 fighter.
In May 1965, a Learjet piloted by Clay Lacy and Jack Conroy established three world speed records, from Los Angeles to New York and back in 10 hours, 21 minutes flight time, with two refueling stops. In December 1965, a Lear 23 flown by Hank Beaird and Ronald Puckett, with five passengers onboard, set a time-to climb record reaching 40,000 feet in 7 minutes, 21 seconds. Think about that folks, that is an average of almost 5,500 FPM climb from sea level to FL400 with a full passenger load.
Less than two years after the first Learjet 23 was delivered to a chemical company in Cincinnati, a new derivative, the Learjet 24 received type certification. A total of 104 Lear 23 were produced in Wichita, Kansas and the future looked bright indeed. But, the Learjet assembly line was about to come to a screeching halt with a crushing recession in 1966.
But, prior to the hard times of 1966, two company pilots, Hank Beaird,and Rick King, with journalist John Zimmerman and Bill Lear’s youngest son John onboard, set 18 international aviation records by completing a round-the-world trip in 50 hours and 19 minutes of flight in the new Learjet 24. In March 1966, the Learjet 24 became the first jet certified to US FAR 25 standards, which superseded the former CAR 4b transport category.
In April 1967, Lear sold controlling interest to the family-owned Gates Rubber Company of Denver and the company was renamed Gates Learjet. Shortly thereafter the Learjet 25, a stretched Learjet 24, with a larger cabin and greater range, was certified and following its introduction in 1968 set a new time-to-climb record of 6 minutes, 19 seconds to reach 40,000 feet.
In August 1973 the Learjet 35, with an even longer cabin and fuel-efficient turbofan engines, made its first flight. Equipped with the long-range tanks the Learjet 36 received certification shortly thereafter. With its more comfortable cabin and superior fuel efficiency at the time of the first energy crisis, the Learjet 35/36 was the right jet at the right time. It was the most successful Learjet to date.
In 1976, golf legend Arnold Palmer and pilots James Bir and Bill Purkey set another round-the world speed record in a Learjet 36 at 48 hours and 48 minutes flight time. The following year, the FAA certified the operation of Learjet aircraft to 51,000 feet, the highest in civil aviation.
And in February 1979 astronaut Neil Armstrong and Learjet test pilot Pete Reynolds set five world records for business jets, including high-altitude time-to-climb, in the widebody Learjet Longhorn 28, the first production plane with winglets. The records stood for nine years before being broken – by another Learjet.
In March 1981 the Learjet 55, the company’s first medium-size jet, received FAA certification, which two years later set a new world speed record flying nonstop from Los Angeles to Paris in 12 hours, 37 minutes with one refueling stop. In the 1980s, Learjet developed the Learjet 31 and 55C, the first aircraft with delta fins.
After a mid 80s bankruptcy and an uncertain future Learjet was acquired by Canadian business jet manufacturing company, Bombardier.
Bombardier put Learjet back on track and energized its product line. By the end of 1990, the company announced the mid-size Learjet 60 project and unveiled an enhanced version of the 31, the 31A. In 1991, Bombardier established the Bombardier Test Flight Center in Wichita, the same year the Learjet 60 made its first flight. Certified January 1993, the Learjet 60 went into service as the world’s quietest business jet, and quickly became the best seller in its category.
Much of the air-to-air footage seen in movies over the past three decades, including the exciting scenes of F-14 fighters in “Top Gun,” was shot from cameras mounted in Learjet aircraft owned by Clay Lacy, a consultant on the first Learjet who owns and still flies the 12th original Learjet. Learjet aircraft have been used worldwide for medevac, air ambulance, air defense, reconnaissance, military training and high-altitude mapping. U.S. Navy and Air Force test pilots train in Learjet aircraft, as well as pilots with leading commercial airlines. Governments and corporations worldwide, including the governments of Ireland and Macedonia, also depend on Learjet aircraft. A Learjet was even temporarily deployed as Air Force One during a trip to South America by President Lyndon Johnson.
A Little Detailed History Leading up to our Learjet 24B
Late in the day on October 7, 1963, the first Learjet 23 (N801L) took flight for the first time in Wichita, Kansas, just before the sun dropped below the prairie horizon. Test pilots Bob Hagan and Hank Beaird knew instantly that they had a winner. The sleek jet, with an elegant design years ahead of its time, flew like a dream. Its systems performed flawlessly and it accelerated on takeoff faster than any jet, civilian or military, they had ever flown. By the time they were ready to land, the skies were nearly dark but hundreds of headlights sparkled below near the Wichita airport.
A local radio station reported that the Learjet was making its maiden flight, and people jumped in their cars to see the sight. Many were spouses and children of Learjet employees, who had worked round the clock for months and were as invested in the jet’s success as the company’s founder. The crowd cheered. Grown men cried. The jet that couldn’t be built was everything it was supposed to be and more. The Learjet was on its way to defining a new category of aircraft, and becoming an enduring icon of business aviation.
William P. Lear was born in 1902 in Hannibal, Missouri, and grew up in Chicago, dropping out of high school in the eighth grade to tinker with radios and dream of airplanes. He made a living building radio sets and developed a coil design that attracted the attention of Galvin Manufacturing Company, where he became chief engineer. Bill Lear and Paul Galvin set out to develop the first car radio and brainstormed the name “Motorola”. The project resulted in Lear’s first patent and, by 28, he was a leading innovator in radio technology.
In 1932 Lear sold his company to Galvin and turned his attention to aviation. He went on to develop the first automatic direction finder (ADF) for aircraft, the first autopilot, the first automatic landing system and the first two-way radio for private planes. The dynamic Lear made and lost several fortunes, but by the 1950s he was an established figure in American business and a millionaire who held more than 150 patents.
In his late fifties, with Lear Inc. a major player in avionics, Bill Lear began thinking about building a moderately priced small jet designed specifically for the business market. Corporate aircraft at that time were principally reconfigured surplus military aircraft originally designed to carry military personnel. Lear thought they were big, slow, expensive barges. He spent two years successfully modifying a Lockheed Lodestar jet with engineers Gordon Israel and Ed Swearingen. But he believed there was a need for a nimble business jet that had a cruising speed of 500 mph, comparable to a jetliner.
Lear came across a Swiss-built fighter-bomber, the P-16, which never went into production but had, among other things, a wing design he liked. Lear moved to Switzerland in 1955 and set up a new company, Swiss American Aviation Corporation. He hired Dr. Hans Studer, designer of the P-16, and integrated a team of American engineers, including Gordon Israel, Hank Waring and Don Grommesh, with members of Studer’s team.
At the time, no one believed there was a sizable market for business jets. In 1962, when the Swiss jet project fell out of favor with the board of Lear Inc., Bill Lear sold his interest in the firm, which then became Lear-Siegler. Lear was on his own and prepared to invest $12 million of his personal fortune in the development of the new business jet. The prevailing wisdom was that it would take $100 million and 10 years to build the kind of business jet Lear wanted. The only way his team could do it was to skip the prototype phase and go right into production. It was a strategy that left no room for error.
As work progressed it became clear that the different work styles of the Swiss and Americans, compounded by language barriers, made it impossible to remain in Switzerland. He selected Wichita, Kansas, as the new headquarters and broke ground on a new complex in August 1962, changing the name of the company to Lear Jet Corporation. Lear hovered over the engineering team, who stopped only to eat and sleep. They revised and re-revised according to Lear’s latest inspirations. They shaved off weight wherever possible to achieve performance targets. Their efforts paid off. Among the innovative design features of the new Learjet were a distinctive wrap-around windshield and a unique outward-opening clamshell door, a feature that continues to adorn every Learjet built to this day.
Simplicity was engineered into the instrument panel, and the cockpit included comfortable seating for pilots. Passenger seats were designed to fold down and swivel. Safety features included dual electrical systems and separate fuel lines for each engine. The only major design change at the late stages was a switch from a cruciform tail to a t-tail design, which improved stability and enhanced the jet’s spectacular silhouette. On Sept. 15, 1963, Learjet #1 rolled out of the hangar. That it was a Sunday did not stop hundreds of employees and their families from coming to watch.
After the first flight in October 1963, Learjet #2 and #3 were completed and the test program progressed into the following year. A hitch occurred when Learjet #1 crash-landed in a cornfield after pilots neglected to retract the spoilers on takeoff. The pilots were fine and the plane was intact but a fuel line ignited and the subsequent fire destroyed the plane. As it turned out, it was a happy accident. Learjet #1 could never have been certified and the insurance money that Lear collected helped keep the company going as the remaining jets completed the testing needed for certification. Learjet #2 (N802L), the first actual production Learjet, was donated to the Smithsonian Institution National Air and Space Museum 14 years later in 1978, and is still on display.
As certification continued, the company began to run out of money, having spent deposits received for the first 22 orders. Clay Lacy, then a United Airlines pilot, signed on as a consultant during his off-hours to help market the jet. Distributor Bob Graf came to the rescue by getting orders for another 31 jets. Minor problems and issues raised by FAA inspectors were resolved one by one. The FAA type certificate was finally awarded July 31, 1964, and the company was able to enter full production, financed by a public offering late that year. The Learjet 23 was on the market.
Was the LearJet not an original idea of Bill Lear?
There is some text that suggests one of Bill Lear’s co-workers or colleagues on the original Lockheed LodeStar modification projects actually suggested a small pure jet powered corporate aircraft should be built instead of modifying the larger military based planes. This may or may not be true, but it is public record that Bill Lear speaking to a group of SAE members in Wichita in 1959 stated the aviation world needs a small business jet and if Wichita hasn’t started it in three years, he was going to build it.
Just to Keep your Attention . . .
This aircraft has the most exceptional climb rate in its class. The model 23 at gross weight will climb at 6,900 fpm. All Learjets are approved for operation at 45,000 feet, and they have much better short-field performance than is common in this category of aircraft. One reason for the climb and takeoff advantage is weight: The model 23, which needs only 2,300 feet to clear a 50-foot obstacle at gross-weight takeoff, weighs only 6,500 pounds empty and grosses at 12,500 pounds. It can fly at 26,000 feet with one engine inoperable. High cruise is 518 mph with a range of 1,875 miles at 485 mph. Woah.
This is a STOL Pocket Rocket and it just keeps getting better and better.
More about the Swiss P-16’s influence on the Learjet design
“I heard that the Lear Jet is in fact based on a Swedish fighter plane.” You would be partially correct, the original Lear Jet was indeed based on a European attack fighter design, however, it was a Swiss design called the P-16.
While Bill Lear’s son Bill Jr., a very accomplished pilot at a very early age, was in Switzerland in 1960 he was introduced to Flug-und Fahrzeugweke AG, or FFA or short, who was working on the design of an interceptor/fighter capable of transonic speeds. The aircraft, known as the P-16, first flew in April 1955 and achieved supersonic flight in August 1956. The P-16 was a somewhat unconventional fighter for its day, more akin to the modern A-10 than its contemporaries.
Bill Jr. was invited to fly the P-16 aircraft after two prototypes had crashed. "They weren't sure if it was the design or the pilot, so they called in Bill Jr. to test the plane," said wife Brenda Lear. "It was this wing design that was incorporated into the Learjet." Bill Jr. was duly impressed to say the least. Knowing this small but high flying, high speed jet was right along the lines of his Dads thinking, he invited his Dad for a look see.
Bill Lear Jr., an Air Force veteran who was in the same pilot class with astronaut Buzz Aldrin, was an experienced pilot well before he joined the service. Lear took up flying at 15. As a 17-year-old, he became the youngest pilot to fly a Lockheed P-38 Lightning - the Army's fastest and most heavily armed fighter during World War II. He raced that same plane for the Bendix Trophy in the late '40s. He was the only foreign pilot to fly the experimental P-16 jet.
This unusual design was dictated by the peculiar needs of the Swiss Air Force, which demanded a plane capable of high transonic speeds, short takeoff and landing (STOL) capability from high altitude fields, good maneuverability, and a rapid climb rate when loaded for combat. FFA's resulting design featured a very thin straight wing, single-seat cockpit, and a single turbojet engine.
This performance was made possible in large part by the design's strong, thin, high aspect ratio wing. One drawback of this very thin wing was the lack of internal volume for fuel, which made necessary the permanent wingtip fuel tanks that came to distinguish the design.
The Swiss government was sufficiently impressed that an order for 100 airframes was placed in 1958. Unfortunately, the crash of a prototype caused the order to be suspended. While the cause of the accident was a relatively minor defect in the hydraulic system that was easily corrected, the Swiss government remained convinced that the design was faulty and cancelled the order.
This unusual fighter had not escaped the attention of Bill Lear. He was particularly impressed by the design's thin, high aspect ratio wing designed both for high subsonic cruise speeds and low landing speeds. The wing was also of very simple and inexpensive construction, combining an innovative and efficient layout of very few ribs, multiple spars, and a thick skin. Lear then approached the chief designer of FFA, Dr. Hans-Luzius Studer, and proposed developing a new corporate jet around the wing of the P-16. The new plane was given the designation SAAC-23 after Lear's new company and the fact that this was Dr. Studer's third twin-jet design.
Bill Lear was convinced that his design philosophy could revolutionize private jet production and create a new market. He believed that what business travelers wanted most was the highest cruising speeds and altitudes possible. To meet that need, he proposed minimizing aircraft size and weight while maximizing engine power to produce a lightweight aircraft with performance similar to that of a military fighter. Furthermore, keeping the weight under 12,500 lbs would allow such a plane to be certified under the light aircraft category (Part 3) of the Federal Aviation Regulations significantly reducing development time and costs.
Lear also believed that costs could be further reduced by designing and manufacturing the aircraft in Europe where labor and material costs were lower. These bare airframes would then be shipped to the U.S. for final assembly and delivery to customers.
Lear’s discovery of the now available P-16 designer coupled with his desire to create a pure private business jet led him to start the design company in Switzerland and to hire premiere aircraft designer Gordon Israel away from Saberliner. Israel had previously worked with Lear in America and would move on and eventually work on the B-1 bomber at Rockwell.
Israel was responsible for the distinctive wedge-shaped nose and well as the overall sleek, stylist appearance. A clean, slender new fuselage was mated to a P-16 wing modified with a slightly thicker cross-section and greater span as well as a swept T-tail tailored for transonic flight. Powering the new aircraft were two General Electric J85 turbojet engines, already in use on the F-5 and T-38 supersonic aircraft. All control, hydraulic, and electronic systems were kept as simple as possible to reduce costs and improve reliability.
Once design work had been completed, plans were put in place to begin assembly of the SAAC-23 in Europe. The wing and wingtip fuel tanks were to have been manufactured by FFA in Switzerland and the remainder of the airframe by Heinkel in Germany. After importing engines, landing gear, avionics, and other systems from the US, the aircraft would be assembled by FFA and then shipped to the US for finishing and delivery. While such multinational manufacturing techniques are commonplace today, think Airbus, this was not the case in 1961.
The manufacturing program soon suffered numerous delays due to administrative hassles. Never a patient man, Lear decided to forego the overseas aspects of his manufacturing plan altogether and instead transferred all the tooling and material to Wichita, Kansas in 1962. Here, he opened the Lear Jet Corporation and renamed his introductory product the Lear Jet Model 23.
So How does the Lear Jet 23 design compare to the Swiss P-16 interceptor/attack fighter? You be the judge.
It should be obvious the design features of the P-16 that was used for the Lear Jet 23 were the thin, high aspect ratio wing and tip tanks. The actual Lear Jet wing was redesigned as a swept wing and made totally wet for fuel storage tanks and enlarged a bit for additional surface area. The ‘area rule’ fuselage squeeze was maintained and probably the retractable gear system. The Lear Jet eventually had a full T tail but retained few other similarities with the P-16.
Most obviously, the Lear Jet 23 had two large externally mounted engines on the fuselage and no bubble canopy. The size and balance are very similar.
Off and Running. I Love it when a Plan Comes Together.
Making its first flight on 7 October 1963, the Learjet 23 was pushed through FAA certification in record time and achieved FAR Part 3 certification in July 1964. The initial target price of the new plane had been $350,000 in 1961, but the transfer from Europe and investment of $4 million into the Wichita factory had raised the cost to $575,000 for a fully equipped and furnished production model.
Even so, this price was a full $150,000 cheaper than the Learjet's nearest competitor. In addition, the only other aircraft on the market that could match the Learjet's cruising speed was the Dassault Mystere 20, a much larger, heavier, and more expensive aircraft. The Learjet also offered a higher cruising altitude and initial climb rate than any other business jet, even surpassing that of many military fighters. It is because of this improved performance and lower cost that the Learjet 23 quickly took the lead in the business jet market, garnering 94 orders by early 1965 alone.
But Wait. What about these radical new jet engines?
Yes, indeed. Not much is found in the history books about the selection of these revolutionary new engines. This is probably due to the fact the Lear Jet was the first civilian airplane to bolt on two high performance turbojet engines. Another major factor was the General Electric Company was aggressively out to sell their new engine and the timing was perfect to meet Bill Lear’s equally aggressive production schedule.
Although GE had recently went head-to-head with Pratt & Whitney and lost the North American Sabreliner business, the T-39A in Air Force lingo, and the Lockheed JetStar, C-140, the company decided to enter into the practically non-existent civilian business jet market.
Using their own company money to develop a fan engine, a project was set up in late 1959. Six months later GE’s Small Aircraft Engine Department announced the CJ610, a slightly modified J85 military engine. This was the engine of choice for Northrop’s hot-smoking, needle shaped world-class T-38 Talon two-seat, twin-engine supersonic Jet Trainer. (Still in production in 2014).
The timing was such that market forecasts highly favored turbines over piston engines and GE had a small, compact engine that could provide greater speed, less vibration, less downtime for maintenance and overhaul, higher resale value, over the weather performance and most of all – the prestige of owning a turbine aircraft.
The Northrop T-38’s sharp wedge shape was designed around two GE J85 turbojet engines weighing less than 500 pounds, yet producing 5,000 pounds of thrust using afterburners. With an 18 inch diameter and only about 4 feet long this was the holy grail for jet engines.
By 1961 GE was developing 2,880-lb-thrust CJ610-1 engines for executive jets. Absolutely perfect timing for Bill Lear’s new Jet. The engine of choice for the Lear jet was not simply a civilian version of the J85 T-38 engine.
The first production Model 23 was delivered in October 1964, but was replaced by the improved Model 24 in 1966 after 104 had been built.
The Model 24, which introduced uprated engines and a number of detail changes, first flew in February 1966 and was delivered from the middle of that year.
Using the J85 gas generator, fuel control, and gearbox as a building block the CJ610 was born. To extend the service life for commercial operation, more conservative methods of engine operation were implemented. First, the gas generator turbine inlet temperature was set approximately 60 deg F lower than then the J85. Secondly, the CJ610 power was monitored by Engine Pressure Ratio (EPR), rotor speeds, and exhaust tailpipe temperature as opposed to exhaust temperature and gas generator speed.
The advantage of this new system, which gave a direct measurement of thrust , was that the engine was not taken to maximum temperature at each takeoff. Finally, the engine was flat rated to higher standard day temperatures (86 deg F) in order to ensure that engine performance would be met at various airport density altitudes and aircraft passenger load configurations.
As more CJ610 engines entered service on executive jets, GE emphasized the necessity of being number one in customer service and support. A 24 hour emergency service phone line was set up to assist technical service representatives around the world. This predated the Cessna Citation type customer care by almost 10 years.
An example of good customer rapport as a quick response telegram to the senior executive on the flight experiencing engine problems:
“Aware of your unfortunate experience. We apologize for any inconvenience that it may have caused you and your associates. Please be assured that upper management at GE is taking a real hard look at this problem, and we’ll be back shortly to tell you what went wrong and what we’re going to do to fix it,”
Evidently this was a winning strategy because in less than 2 years, the CJ610 engines accounted for over 50% of the total turbojet powered business aircraft in use. Sales for the GE CJ610 outpaced competitors Pratt & Whitney and Bristol Siddely Viper 20.
CJ610 production continued until 1982 when 2,059 engines had been manufactured. The top two production years were 1965 (299 engines) and 1966 (369 engines) after that production slowly declined due to competition from other fanjet engines.
The CJ610-6 was the most popular engine model with 808 engines manufactured for the Learjet Model 24B/D and the Model 25B/C. Lear was GE’s first customer for the CJ610. I bet he got a great discount on volume pricing.
The CJ610-6 engine that powers our LHC Model 24B is about 41 inches long, 17 ½ inches in diameter and weight only 390 pounds. This one is referred to as a single-spool turbojet with a two stage turbine spinning at 16,500 RPM producing 2,950 pounds thrust.
What are the differences in all these early model numbers?
Mostly the size of the cabin, i.e. number of seats for passengers and the fuel load. Of course, all these slight variations tally up to the various Gross Weights and therefore performance impacts. The later 23 and 24A models were powered by CJ610-4 General Electric turbojets with 2,850 lbf for takeoff.
Starting with the first improved 24 series model, the airline transport category certification was introduced. This required much stricter design and testing criteria and more systems redundancy. Later model 24 series has thrust reversers included to further improve short field landing capabilities.
The 23 and early 24 series models are easily identified from a distance by the large single oval window on the left side behind the entry door and the 2 large oval or rounded windows on the right fuselage.
The Learjet 24B saw upgraded CJ610-6 engines and a Max Gross Weight of 13,500 lbs. Learjet 24E and -F models utilized the CJ610-8A engine, had a greater fuel capacity for increased range and had square cabin windows in place of the oval windows of earlier models.
A total of 258 Learjet 24′s were produced, of which 12 were the 24F, before the line was terminated in favor of the turbofan-powered Learjet 25 series in 1979. The Learjet 24F is powered by a pair of General Electric CJ610-8A turbojet engines rated at 2,950 lbs. of thrust each. Inspection interval on the engines is 5,000 hours.
Specific Model 24 Variants
Learjet 24A Standard version. Converted from Learjet 23. Takeoff weight 13,499 pounds. FAA certified on November 9, 1966. 81 aircraft built.
Learjet 24B Improved variant, powered by two 2,950 lbf thrust General Electric CJ610-6 turbojet engines, and 13,499 pounds maximum take-off weight. FAA certified December 17, 1968. 49 aircraft built.
Learjet 24C A light-weight version of the 24B, fuselage tank not fitted which would have caused a reduction in range. The Learjet 24C project was abandoned in December 1970. None built.
Learjet 24D Similar to Learjet 24C, however by changing surface tanks range and takeoff weight were increased to 6,129 kilograms (13,512 lb). Round cabin windows replaced by angular. FAA certified July 17, 1970. Replaced the 24B in production. A reduced gross weight (restricted to 12,500 pounds (5,700 kg) version was also available (the 24D/A). 99 built.
Learjet 24D/A Light-weight version with a restricted take-off weight of 5669-kg (12,500-lb),
Learjet 24E and 24F
Two new versions were announced in 1976 the 24E and 24F, they introduced a new cambered wing and aerodynamic improvements to reduce stall and approach speed (Century III wing). The 24E did not have a fuselage fuel tank for higher payload but shorter range. Some 24E models had the fuselage tank installed later to restore range. Powered by two 2,950 lbf (13.1 kN) thrust General Electric CJ610-8A turbojet engines. On April 15, 1977, the FAA approved extended ceiling to 51,000 feet (16,000 m), the highest level then achieved in civilian aviation. 29 aircraft built.
Learjets have long had a reputation as excellent performers, and the Model 25 and shorter-cabin Model 24 are competitive with many modern jets. The aircraft was originally certified to FAA Part 25 rules, which mandate relatively large safety margins compared with other small jets during critical operations like engine failure after takeoff. The Learjet also has no life limits on its airframe, which means it can be operated indefinitely, as long as it is maintained.
About 500 of the Learjet 24s and 25s manufactured between 1966 and 1982 remain in service, and plenty are on the market. It is not the initial purchase price of these old birds, it is the maintenance and operating costs that are so high.
Noise abatement impact
In 2013, the FAA modified 14 CFR part 91 rules to prohibit the operation of jets weighing 75,000 pounds or less that are not stage 3 noise compliant after December 31, 2015. The Learjet 24 is listed explicitly in Federal Register 78 FR 39576. Any Learjet 24s that have not been modified by installing Stage 3 noise compliant engines or have not had "hushkits" installed for non-compliant engines will not be permitted to fly in the contiguous 48 states after December 31, 2015
High Accident Rate
But there was a downside to the Lear 23's fighter like performance: a fighter like accident record. Lear's creation was a demanding aircraft to fly, unforgiving of pilot errors.
Within three years, 23 Learjets had crashed, four of them with fatal results. In a fleet of only 104 aircraft, that was a shocking statistic. By 2005 more than half of the Lear 23 fleet had suffered accidents, 13 of them fatal. One out of eight Lear 23s ever built has ended up killing somebody.
Lear quickly recognized the problem, and in 1966 introduced a new model, the 24, with improved low-speed handling qualities. The 25, 28, and 29 Models followed. Their accident rates improved, but were still higher than other corporate jets'. Production of the 20 series came to an end in 1982.
The Learjet name lives on in the 30, 50, and 60 series, which are larger, more efficient, and safer. But they lack the original's eye-popping performance. The rich guys in back may prefer the roomier later versions, but for a pilot who's up to the task, there's still nothing like a Lear 23.
In a Nut shell.
The Learjet 24 was designed as an improved version of the Learjet 23, which was limited in gross weight and rushed to market. Engineers designed the model 24 to accept up to the full gross weight permitted by FAR-25 standards.
Other improvements introduced in the Learjet 24 included:
increased cabin pressurization, to allow a higher operating altitude
the addition of one extra window on each side of the cabin
more powerful engines
a new windshield
auxiliary fuel in wing tip tanks
a fire-extinguishing system for the engines
With these changes, the LJ24 became the first business jet to be certified under FAR-25. Our model 24B is still two model updates away. There was the Model 24 and then the 24A prior to the one Lionheart Creations chose for FSX/P3D.
What is in a name?
Have you noticed that the pure Bill Lear models are named Lear Jets as in Lear Jet 23, but the Gates Lear Jets are named Learjets as in Learjet 28. Gates changed the name to be one word rather than two, but it is not crystal clear for the Model 24 and 25 where both Gates and Bill Lear were involved.
The several company names are as follows:
November 1959, Swiss American Aviation Corporation. Working titles for the first aircraft were, SAAC-23 and Tina Jet located in Altenrhein, Switzerland (St Gallen)
September 19, 1964, Lear Jet Industries, Inc. Wichita, Kansas, a publicly owned company
In 1966, the name of the company was changed to Learjet Industries
1969, the company was merged with Gates Aviation and the name changed to Gates Learjet Corporation.
1990, Bombardier Aerospace purchased the Learjet Corporation, the aircraft were then marketed as the “Bombardier Learjet Family’.
In August 1987 Gates announced that it would sell its 64.8% interest in Gates Learjet to Integrated Acquisitions Inc., a wholly owned subsidiary of Integrated Resources Inc., of New York. This led to the moving of most production from Tucson back to Wichita.
In mid-1989 a financial crisis in its property business forced Integrated Resources to seek buyers for Learjet once again. On June 29th 1990, it was acquired by the Canadian company, Bombardier Inc. and the name was changed to Learjet Inc., a division of Bombardier.
Can’t we improve the Stall Characteristics?
The original LearJet, though an instant success , had shortcomings that became painfully obvious to aviation consumers. The original wing on the Lear 23, and some of the early Lear 24s, earned the nickname "Flash" because of it's stall characteristics. In most aircraft an impending stall is felt by an aerodynamic buffet on the controls, due to the slick wing of the early Lear, stalls came with no warning at all, often ending tragically.
Additionally, many military pilots coming from the fighter jets of the time had the mentality that since the Lear design was based on that of a fighter, it should have the same limitations. Before people could grasp what was happening, an alarming number of LearJets would simply disappear from radar screens with signs of alarm, they would later be found in many pieces scattered across a field.
Pilots were taking a corporate aircraft into near supersonic speeds and producing a shockingly severe control flutter that would eventually tear the aircraft apart.
After discovering the abrupt stall tendencies and erratic overspeed characteristics, designers altered limitations of the aircraft and began the first of many improvements to the standard wing.
The Day the FAA (and the Insurance Check) saved Lear Jet.
The prototype Lear Jet Model 23 (N801L) had already flown and Lear had hoped to save time by obtaining the type certificate under FAR Part 23 rather than the more stringent Part 25, which governs transport-category aircraft.
But the Wichita FAA, then not very familiar with jets, tacked on some additional requirements that threatened to slow down certification. In reality, the airplane met or exceeded the most important of Part 25 criteria; the main exception was the bird-proof windshield, later added as part of the changeover to the Model 24.
One of the FAAs additions required that Lear establish balanced field lengths; and it was here that disaster struck. Testing for single-engine climb performance, with an FAA test pilot in the left seat and Lear's pilot in the right, N801 Lima left the ground with one engine actually shut down (normally not done until the very end of the testing phase) and the spoilers inadvertently extended. In this configuration, it was something of a miracle that the airplane flew at all; as it was, even with the gear retracted, it refused to climb much beyond ground effect, and it just managed to clear some trees at the end of the field.
According to Clay Lacy, it was late in the day and just starting to rain. The FAA Test Pilot was so confident in the Lear’s short field takeoff capabilities he was saving time by taking off downwind or whichever directions they were facing after the last landing. In a rush, to complete the one-engine out tests before dark that day, the crew failed to use their checklist and with the deck totally stacked against them attempted a downwind takeoff in a light rain with the wing spoilers fully deployed and one engine totally shut down. The Lear Jet flew for one and a half miles in this condition before plowing into a wet field.
In the cockpit, meanwhile, confusion reigned: an engine restart was unsuccessful because of improper procedure, and neither pilot thought to check spoiler position. Soon the airplane began to settle slowly and, with a field just ahead, the pilots elected to put the gear down and ride it in. The total loss of this prototype should have been a crippling blow. A broken fuel line was spilling fuel and the crew evacuated and the wreckage soon burst into flames. The plane was a total loss but was fully insured. Mainly because the FAA was flying the plane, the insurance company paid off and the $500,000 kept the company afloat for another couple of weeks.
Bill Lear was immediately on the phone to the FAA, Senators in Washington, and anyone in the government that would listen to him, crying ‘You guys destroyed my airplane, now what are you going to do about it?’ In a previously unheard of reaction, the FAA Type Approval team was available to the Lear team basically 24 hours a day until their work was completed.
The second and third prototype aircraft were made ready and being first flown within a few weeks. On July 31, 1964, less than two months after the accident and nine and a half months from the Lear Jet's first flight, FAA Administrator Najeeb Halaby personally flew to Wichita to present the type certificate to Lear. The first production Lear Jet 23 was delivered on 13 October 1964 to the Chemical and Industrial Corporation of Cincinnati, Ohio. It went out the door for under $600,000.
Lear increased production to 10 airplanes per month. While the plant was being expanded, he began work on recertifying the airplane under Part 25 which was later named the Model 24, and immediately started developing a stretched version (the Model 25).
In 1965 a Lear 23 established a Los Angeles to New York and return record of 10 hrs 52 min flying time, and a time-to-climb record to 40,000 ft - 7 min 21 sec - with seven people on board.
Don’t they all look alike?
Distinguishing a Model 23 from a 24 is tough, mainly because most of the changes were internal (improvements in the various systems) and on paper (weight and performance numbers). The two most obvious external differences are the vortex generators, small metal tabs that project above the wing ahead of the ailerons and the windshield. A Model 23 has a set of vortex generators on the underside of the wing as well as the upper surface; 24s have them only on the upper surface.
The Model 24's windshield, befitting a transport-category airplane, is a bird-proof design with a T-shaped stiffener on the vertical post separating the two halves; if this stiffener is missing, you are looking at a Model 23. The factory's records, in 1978, indicated that 12 of the 88 Model 23s still flying were Model 24s in every respect except serial number.
After the Model 24D all the models and Variants seemed to get a little longer with an extra couple of windows.
Originally Intended for single-pilot operation
At the 11th hour, the FAA disapproved the single-pilot request for the Lear 23. Most of the earliest layouts was for a crew of two and for five to seven passengers with a reduced fuel load.
There were 104 Model 23s built, although the serial numbers only run from 001 through 099. The difference is five A models, the existence of which stems from the backlog of orders just after the airplane received its type certificate. Lear, during the course of a normal day's wheeling and dealing, would promise yet another airplane to a special customer. To keep this person from having to wait a year for delivery, Lear would sneak him in at the head of the line by creating an A model and bumping all the numbers back one.
In those days, there was no such thing as a standard Learjet. True, the basic airframe/engine combination had been frozen by the type certificate, but the systems and, in particular, the instrument panel were considered fair game for new ideas. The first 30 production aircraft to be completed were powered by 1293kg thrust General Electric CJ610-1 turbojets, but the remainder of the production run of a little over 100 Lear Jet 23s had CJ610-4s of similar thrust.
To Lear, all Learjets, even those brought in for routine maintenance, were prototypes. As a result, pilots about to fly an airplane only a few serial numbers away from their usual one still had to take time to locate switches in the cockpit. The first 14 airplanes provide the most extreme example of this. They all had left-hand control panels, so confident was Lear that single-pilot certification was just around the corner.
The FAA decision not to approve the Lear Jet 23 for single pilot operation came at the last possible minute, but the basic type certification to sale the aircraft was more important. There were no other private jet aircraft approved for single pilot operation. This would come several years later with the Cessna Citation. Built on the other side of Wichita's Mid-Continent Airport.
The Model 24 Learjet was the first unit in the series (N427LJ) and made the flight May 23-26, 1966.
The notorious Go-Fast Switches
A fairly common and totally illegal modification by companies that had no scruples whatsoever, or no understanding of high speed aerodynamics combined with high altitude meteorology put what the industry called "go fast switches" under the panel of some of their Learjets. These switch disabled the overspeed warning and stick puller.
The 20-series Learjets have so much power they can easily exceed redline airspeed in cruise flight. Doing so is an exceedingly serious affair because at some speed past redline it induces what is known as "mach tuck". When that happens the airplane begins to pitch down, eventually uncontrollably until the airplane violently comes apart. The Lear literally disintegrates in midair.
There is a very limited time for a well-trained crew to take precisely the correct action to save the airplane and themselves. Especially in the 1970s and early 80s there were some inflight breakups of Learjets, usually freighters. It was later discovered that go fast switches were to blame in at least some of those tragedies.
The FAA stepped in and inspected every registered Learjet and removed this stupid modification.
Although the road for the Learjet has been bumpy and uncertain at times, in the end, Bill Lear accomplished what he had set out to do. His small personal jet has reached that special status in the world when every corporate jet is referred to by the average person on the street as a "Lear Jet"
OK, enough about Bill Lear and the real world, let’s talk about this Flight Simulator model from LHC.
The actual performance data for the LJ24B is woefully lacking but let’s go with what we have and see where it leads us.
The design team did not had an Airplane Flight Manual, AFM, or a Learjet 24 Performance and Information Guide, or any such very model specific set of instructions or guides. What they went by is the Wiki provided General characteristics and Performance table. This one has been copied endless times to other website and most often it is for the last Model 24 variant – the Learjet 24F which is still in the family but yet still different than our 24B. But, nonetheless, this is what was used by the design team for the Lionheart Creations LJ24B.
Web based aircraft specs are most often not correct for the model numbers stated.
A couple of things to keep in mind. It is very common for free data on the internet to be full of errors and omissions. Seldom do I find something really useful, really free. It is common for mph and knots to be used interchangeably, misused and sometime we are not told which is being used. (NASA is one of the worst offenders at this)
The Learjet 24B as delivered from the factory in early 1969 or so would have had everything in mph, not knots. This doesn’t mean that the first, second, or last owner of any particular model 24B airplane didn’t do a wholesale change-out or upgrade in the panel. Many times more than once.
Somewhere I read that about half of the Model 23 Learjets still flying have had upgrades to make them Model 24 Learjets in everything except serial number. This would include replacing the windshield with the thicker bird proof tested glass with the T bar stiffener at the top center. It would probably include a totally new electrical system, new pressurization system and some assortment of new gauges and avionics. At this time, most owners would probably get airspeed indicators reading in Knots/hour. They may or may not get any leading edge updates to the wings.
Later model Learjets, even those in the 20 Series have many differences than the Model 24B so tread lightly when wading through performance charts and data for these later and larger models with different weights, differing fuel capacity and different or updated systems. A likely reason Wiki has used the Model 24F as representative all 24s is because it was the last 24 variant. The problem with using the 24F performance data is the engine was also an updated CJ610-8A and this model has a different wing design than the 24B. Even the Wiki page has conflicting specs on the same page.
All Learjets are certified for 2-pilot operation. Even though Bill Lear was so sure that he would get his single-pilot certification request approved that the first 30 models off the assembly line only had primary flight instruments for the left seat, it didn’t happen that way. No Learjet was ever certified for single pilot operation.
The Model 24B was the first variant to receive the CJ610-6 engine. Unfortunately that didn’t last long as the 24E and 24F have the -8A engine and came with a totally new cambered wing and aerodynamic improvements to reduce stall and approach speed (Century III wing). The 24E and 24F were the first civilian jets to be certified to fly at FL510.
There were a grand total of 258 Learjet Model 24’s produced according to most sources.
Let’s see if we can narrow down the information we have for the LHC LJ24B
24 & 24A
Model 24 and 24A, mixed (had the CJ610-4 engine, not the -6)
13,500 lb. TOGW rev. systems and interior. CJ610-6 engines.
New angular windows, 12,500/13,500 TOGW CJ610-6 engine
CJ610-8A engines, FL510 approved (1977)
Learjet 24A Standard version. Converted from Learjet 23. Takeoff weight 13,499 pounds. FAA certified on November 9, 1966. 81 aircraft built.
Learjet 24B Improved variant, powered by two 2,950 lbf thrust General Electric CJ610-6 turbojet engines, and 13,499 pounds maximum take-off weight. FAA certified December 17, 1968. 49 aircraft built.
Learjet 24C A light-weight version of the 24B, fuselage tank not fitted which would have caused a reduction in range. The Learjet 24C project was abandoned in December 1970. None built.
Learjet 24D Similar to Learjet 24C, however by changing surface tanks range and takeoff weight were increased to 6,129 kilograms (13,512 lb). Round cabin windows replaced by angular. FAA certified July 17, 1970. Replaced the 24B in production. A reduced gross weight (restricted to 12,500 pounds (5,700 kg) version was also available (the 24D/A). 99 built.
It looks like our model will have a Maximum Takeoff Gross Weight of 13,500 lbs and have CJ610-6 engines delivering 2,950 lb-f each with revised systems and interior as compared to anything previously made. It would also have been built between December 17, 1968 and Dec 31, 1971.
There were only 49 total Model 24B built. This particular model is one of the ‘later’ models of the early Lears. The follow-on Model 24D, there was no 24C, was the start of smaller but more plentiful fuselage windows, stretched cabins with more seats and rapid design changes in systems and other improvements.
What seemed to have remained stock was the bullet style look with short wings, tall T tail and tip tanks for at least the next ten years when the Model 24E and F were introduced with the CJ610-8A engines, a totally new wing design (Century III) and approved for FL510 operation. This was the very first civilian airplane approved to fly at 51,000 feet. (Learjet 28/29 had winglets)
Using the designer supplied Wiki data the typical Empty Weight is 7,130 lbs. (The normal spread is 7,100 – 7,300 pounds)
The Fuel Load comes from the cockpit Fuel Panel on the console.
Left Tip Tank
Left Wing Tanks
Right Wing Tanks
Right Tip Tank
$1.20/pound for Jet Fuel. Really?
This sounds insane, but $10/gal for Jet Fuel is just around the corner. Can you imagine trying to convince someone in 1964 that kerosene for these Lear Jets would rise to such astronomical numbers.
To clarify my point. When Clay Lacy was giving free rides to most anyone in Hollywood that he thought would repeat the words Lear Jet it costs about $115 to fill the tanks, today that same amount of fuel would be $6,580. Lacy calculated the direct operating cost in 1964 was $135/hour. He figured fuel was about $35/hour based on 0.14/gal.
The Learjet 23 has it’s very own postage stamp.
Marshall Islands, it doesn’t get much better than this.
Super Closeup views and sounds of a Learjet 24
This excellent video has slow scan, startup, flying routine, taxi and shutdown sounds. Taken at Chino Airport, 2014 Planes of Fame Airshow. Clay Lacy flies N3137 (#123).
Let me highlight a few items that caught my attention with the LHC model.
(The first few hours or days of orientation)
The Lionheart Creation’s Lear 24B is not based on a real world airplane parked in a hangar someplace with stacks of HD photos of every nook, cranny, instrument or panel like some high-end add ons. This sim design does not replicate a specific date of manufacture or a particular serial number model.
It is, however, a believable edition that, within the realm of FSX/P3D, can be flown using real world manuals, book, guides, etc, provided someone can find such books and manuals. Most free ones cover the 20 Series with little specific attention to the 49 total 24B models of the bigger grand total of maybe around 750 total 20 Series.
It has a realistic panel layout, a believable copy of the original, but with some modern and updated gauges, meters, and switches. There was not a ‘standard’ panel or cockpit layout for the early Lear Jets. They were modified right up to the last minute before delivery. An owner could request most anything be placed at his or her whim. Good photos are also rare. Plus the model variants seemed to change with the weather.
- Easy to read the Flaps deployed indicator with Takeoff positions clearly shown on gauge. Good location also.
- Gear operation switch located in an easy to reach location with 3 greens and 3 reds that should be hard to overlook.
- Working meters that react properly to electrical load and switch positions.
- Easy to read frequencies on radios, easy to operate. Click spots properly placed and workable.
- Has a big digital Altitude Select right in front of my nose.
- Has airliners (Boeing) type remote Autopilot switches (Very unlike early Cessna Citations) with great movement and use indicators. Has a full AP – quite something for its day.
- Has a nice easy to read Trim View panel with all three trim positions shown.
- Has workable and correct annunciators and alarms. Yellow for cautions, Red for warnings.
- Has a DME distance computer (quite something for the mid 60s)
- Excellent sound package inside and out. Switch sounds, gyros, wind noise, roaring engines.
- Unique wing temperature gauges, wet wings at high mach speeds can heat fuel to unsafe levels. (fully modeled)
- Has the appearance of expected systems, de-ice, pressurization (minimal), fuel management (exhaustive), electrical, engine monitoring. Environmental and hydraulic systems are mostly dummy gauges.
- Very complex fuel management system, excellent graphic displays, fuel dump, fuel transfer and cross flow modeled. Probably the best available for recent corporate jets.
- Digital fuel flow counter on fuel panel, rotary selector for fuel in tanks plus total
- Good light management and control, dome, instruments, rear cabin
- Clickable annunciators with lamp test mode
- 2d panels for fuel management electrical and lights, throttles, etc
- You can drag the 2d Full (sic) Panel up or down for approaches or working with the lower panel at cruise. (in lieu of having additional panels)
- Outrageous Bubble Placard info system for initial orientation, ie, Panel Orientation for Dummies.
- Has a nifty V/S mode for climbs and descents – this will hold a given angle, either up or down and maintain a heading using a wing-leveler. This does not use Hdg, Nav or Alt but does require the AP to be engaged. It is not a VNAV system. V/S switch is not located on the AP but on the Remote AP switch panel – Pilot and Copilot sides.
Special Missions in the Lear Jet
Special missions have been a part of the Learjet's heritage almost from day one. In 1965, the first Learjet customer, Chemical and Industrial Corporation was called upon at a moment’s notice to pull the seating out and replace them with a stretcher. The mission was to pick up a NASA engineer suffering a medical emergency at Cape Kennedy Florida and transport him to Cleveland Ohio, which they did in time to save his life.
What is it like for a Cessna pilot to actually Fly a LearJet?
It is probably a different experience for each pilot that has the unique opportunity to fly any model Learjet. But, I am sure it was an unforgettable experience. Mine was a long time ago when these things were brand new and probably unattainable to the average Cessna, Mooney or Piper pilot but it seems like just yesterday to me.
I was your typical small Cessna pilot however, I had some unspent GI Bill funds and for a while it seemed like someone just kept adding additional free training to my kitty. I had gotten a Commercial, Instrument, Multi-engine and CFI on my GI Bill as a reward for my US Navy service in the mid-1960s. I also had a telegram, remember Western Union?, in hand from Ansett ANA Airlines with a firm offer of employment if I added a type rating and first class medical to my collection. Evidently it didn’t matter what airplane it was as long as it was a heavy – meaning MTOW of 12,500 pounds or more.
A quick survey of available flight schools on the East Coast of Florida offering GI Bill approved type ratings made for a very short list. I don’t think a total of one could be considered a list, maybe two but with a question mark. Daytona Beach Aviation was eager to enroll me as their first student for their recently acquired DC-3 that would meet the ANA / Ansett stipulation for sure. The other choice was an offer for a type rating in a brand new LearJet Model 23 sitting at West Palm Beach Gates/LearJet distributor.
The Learjet offer was most appealing but had two drawbacks. One, the LearJet folks were not an approved Flight School for the US Government GI bill and the Learjet weighed exactly 12,499 pounds. I spent lots of nights having nightmares of arriving in Brisbane, Australia to find out my new LR-Jet type rating missed being a heavy by one pound.
To shorten the story, I chose the DC-3 type rating route and 15 hours of dual and an exhaustive 2 hour check ride in terrible IFR weather I had my type rating. With my instructor in the right seat doing all the stupid things a snot-nosed wet behind the ears copilot would do like Flaps up when I called for Gear Up and request the wrong approach when I asked for an ILS to absolute minimums. I was now in possession of a spanking new ‘heavy’ type rating thanks to the non-DC-3 rated FAA Examiner with bad breath that rode in the Jump Seat for the 2 hours.
The plot thickens . . . .
The Learjet folks were not ones to give up easily so lo and behold I get an offer for a ‘Checkout’ in one of their slick new Lear Model 23 jets. This would come complete with a full half day ground school overview of systems and emergency procedures and a 3 point cross-country flight including cruise at FL410. Before I could call to make an appointment the next morning, they sweetened the deal to include a minimum of 3 hours flight time and they would bring the plane to me at my home airport. So I say, well, let me think about that . . . for a nanosecond. YES, YES, and YES.
Then I had to call back and ask the question. How much is this going to cost me? Are you ready for this? I can’t remember exactly but it was either $650 or $675 total. Really? Yep, I kid you not, This was 1970 and a dollar was still worth about a dollar and nobody even thought twice about the price of Jet Fuel. It was less than a quarter a gallon even in West Palm or Miami. Unbelievable.
Ok, I am all bugged eyed but wide awake during the ground school. Complete with laminated graphics on an easel, but in black and white. Kinda hard to follow those lines and pipes in B & W. The instructor must have thought I was either brilliant or a real dumbass because he would ask – Any Questions? About every 5 minutes and I couldn’t think of a single question, other than when do we takeoff? I kept thinking that someone is going to realize they made a big mistake on the price and call this thing off before I can get the gear up. I graduate the abbreviated ground school and we skip lunch.
OK Sir, start engine number one. WHEEEEE.
My Lear Model 23 flight checkout started at TiCO airport, now named Space Coast Regional, just outside the West gate of Kennedy Space Center. The plan was to fly a triangle pattern up the East Coast of Florida to Jacksonville, KJAX, then SW for a touch and go or two at Tampa, KTPA. then climb East and cross Orlando at FL410. McCoy, MCY, the Disney airport, was an AFB back then, and then land back at TICO.
The only thing I did correctly was to take off and land at TICO. I was about a mile behind the airplane for most of the 3 hours. It started with me making a smooth right turn onto Runway 9, about 5,000 feet of concrete with the wind on my nose as I heard my Non-Federal Control Tower lady’s voice in my headset saying, ‘Ray, you are cleared for takeoff, North departure, be advised Restricted Areas blah and blah are active.’ That is when the engine roar came alive. Ohhh.
Brakes on, as I eased the throttles forward to the stops the engine noise was insane. Just about the time I released the brakes, I hear “Airspeed Alive” so I look down at the airspeed indicator, very soon thereafter I hear “80 mph”. My checkpilot called Vr and said rotate slowly and put it right here. I looked over and his hand was at a 10 - 15 degree angle. I never heard v1 or v2, or any speed callouts other than the 80 mph, but I do remember hearing ‘Yaw Damper On” and “I have the gear”. I don’t know what happened to the flaps. The next thing I know I am passing through 200 mph and still on the 090 degree heading. The gear comes up in a flash, that design did not come from Cessna.
The time from when the nose gear left the concrete and the minute or so until I started my first climbing left turn at around 2,000 feet was something to behold. I still get goosebumps just thinking about the climb power and speed buildup of the Lear. This is as close to riding one of the nearby Project Apollo rockets just across the river as most mortals will ever get.
I rolled left for my turn toward Georgia and was cautioned not to overbank. The problem was I couldn’t see the horizon that I was familiar with when climbing out. Somewhere along the way, somebody made a power reduction to about 90% and I got established on a somewhat Northwest heading. The VSI was pegged at 6,000 FPM and my checkpilot is saying something about attitude and speed control. Sir, use your thumb on your yoke to trim I hear someone saying. Oh, were you talking to me?
Ok, lower your nose and hold 250 for the climb. Using my thumb trim button I lock in 250. A quick instrument scan stops at the VSI still pegged out at 6,000 FPM. I wonder if it is working. It must be the altimeter is still spinning.
Boy, this new Lear feels so solid, not heavy, just sold like a rock. Usually, I am bouncing around in the Florida thermals, first this way then that way and up and down. Not today, smooth sailing. I could get use to this. I start to think, Hey Stupid, why didn’t you opt for the LR-Jet rating instead of that oil leaking, foul smelling, low and slow moving Douglas Dakota?
Climbing a mile a minute 50 miles from takeoff.
I had forgotten what altitude I was supposed to be but I remember looking left and recognizing Daytona Beach airport out my window, still climbing at 6,000+ FPM on reduced power. I remember thinking something along the lines of that we are climbing more than a mile a minute and that gets me further behind the plane. We are now 50 miles North of TICO and I hear my checkpilot talking to Jacksonville Approach. What a blur.
Did I mention that yes, I busted right through the Kennedy Space Center Restricted area, maybe both of them, but was out the other side before the two F-4 Phantom interceptors scrambled from Patrick AFB could get us in their sights. The next thing I know we are approaching the port of Jacksonville at some mid-twenties flight level.
So we swing around and engaged the autopilot and I get this really nice pep talk along the lines of . . . Don’t worry about it, you are doing just fine. All Cessna pilots are a little behind the airplane the first few hours. Yeah, right, but not a mile behind.
Now that I had ‘caught up’ with the plane I was going to make a picture perfect descent and approach into Tampa. Wrong. I whizzed past those big pot holes in Central Florida so fast that I was convinced that it was not possible to slow a Lear Jet down from one coast to the other. What I totally missed was the fact that a slick, fast and expensive Lear Jet get priority handling and Tampa Approach gave us a straight in approach to one of their South facing very long runways.
Hello Tampa, Goodbye Tampa
When it was obvious that there was no way I was going to get down to sea level anytime soon and I was having trouble even getting the speed below 250 mph. My checkpilot asked for a very large sweeping turn out over the Gulf of Mexico to set me up on a ten mile final for runway 01, an 11,000 runway. That seemed to work but I still came in too hot and would have used up half the runway if I was landing. We executed a missed approach and came around again and this time I have all the time in the world to catch up with the airplane and control my speed.
I guess the checkpilot just flat did not want me to use the spoilers to kill the excess speed. When I finally asked if the spoilers worked, he just frowned and said something like ‘You need to learn to fly the plane without spoilers first’. It just didn’t seem to be the right time to ask Why?
Ok, a smooth gentle turn to downwind and let’s do it again. This time we leave the first notch of flaps extended and drop the gear as we turn downwind and I keep telling myself this is ‘slow flight’, this is ‘slow flight’ as I make these large sweeping turns and line up for a full stop landing. The dumbest part was when ground control asked where I would like to go? I had no idea. I finally stammered, I would like to taxi back for takeoff. I quickly stole a glance to the right seat to see a positive nod.
This airplane is so smooth that if you ease the nose up just a little too much you are making a zoomed inertia climb, lower the nose and the speed builds up so quickly you can’t believe it. It felt like full throttle all the time, even when it was almost at idle.
You can’t see the nose of the Lear from the pilot’s seat, it looks like you are flying a hang glider, well not really, but, you can see most of the left wing and that huge Tip Tank. You can see the rows of little metal tabs on the wing directing the airflow over the ailerons and the horizontal tail surface. Wow, those clouds sure are moving fast. Wait, that’s me moving fast.
The only time I felt like I was in control was when I was climbing to FL410, even on one engine.
The unimpeded climb to FL410 was over in no time and I think we were at level cruise at mach .86 or so for a couple of minutes and started down again. The only reason we didn’t set some new climb to altitude record was the simulated loss of an engine for a few thousand feet of climb. Other than the engine instrument indicators and alarms, it was difficult to believe you could just keep on keeping on with one engine out. I guess each one is so powerful and they are mounted so close together losing one is not a big deal, unless of course you are way up there and then you have to come down rather quickly.
Somewhere on the way up I am just about to say the cockpit is not nearly as noisy as I thought it would be when I nearly jump out of my skin when I was sure I had just experienced my first bird strike. I evidently looked like I had seen a ghost, I guess, but enough to get a genuine smile from my now relaxing checkpilot. He quickly said that was a very common high altitude sound and I should expect more just like it. This exploding windshield sound is just the reaction to rapid changes in temperature and pressure. By making sounds like a big firecracker? Holy smokes.
I had just crossed Central Florida including a handful of busy airports and two Air Force Bases and I don’t remember seeing any traffic whatsoever. Approach control had me going generally North or South the whole time to make sure I avoided the Space Center when coming down from FL410. Word evidently travels fast.
Oh, he let me use the spoilers this time. Now that is the way to slow a speeding bullet down in a hurry. Just don’t forget to retract them before too much speed bleeds off.
I made an OK approach and landed on the same runway that I used to violate the Restricted Areas. My touchdown was one of my best as I pegged my over the fence speed and greased the mains onto the runway and held the nose a few inches above the runway and it touched down ever so gently. Even the distinguished looking silver haired checkpilot said, Nice Landing, sir. He was probably 30 years my senior. I didn’t see fit to tell him that was my 10,000th landing on that runway, just usually a whole lot slower and a no tip tanks.
On the descent I got a some lifelong instruction of how to land a Lear Jet. Knowing I was from the Cessna camp, my checkpilot said I would have a tendency to flare too high and too much. Assuming he knew a little more than I did, as I only had one official Learjet landing under my belt, I listened intently. He advised me to approach the landing much flatter than anything I had flown to date. He said the perfect approach would look like the nose wheel was about 6 inches off the runway when the mains touched.
I glanced over to the right seat when I was about 3 feet above the concrete and he had an almost smile on his face with his left hand indicating a perfectly flat attitude. Not this or this but flat – nose gear 6 inches above the concrete flat. Oh, and remove any remaining thrust just as the mains touch.
I never flew with him again, but I did get calls from time to time to fly right seat on some ferry flights or airplane deliveries when Gates sold a new Lear that wasn’t picked up at the factory in Wichita. By then, I had learned to fly fast.
I really should try to recreate the same flight using the LHC Learjet 24B in the simulator. Surely I would do better the second time.
Before I was left standing on the ramp with my jaw hanging, I walked around the Lear one more time and just let my hand slowly drag across the whitest and smoothest wing surface I have even seen. The Learjet wing doesn’t feel anything like a Cessna or Mooney or Piper wing, it feels more like it is solid steel, I mean that literally, nothing flexes, nothing gives, no dips or humps, no bumps, it looks like it has ten coats of paint and is bullet proof.
No one had seen a Glasair or Lancair or similar fiberglas and composite type surface airplane back then but, the Lears looked a lot like these composite plastic airplanes of the future, just much heavier.
So what am I to gather from that Lear 23 Orientation?
That it will take some time to adapt to the much higher speeds and altitudes if your total experience has been in slower general aviation airplanes. Higher stall speeds, outrageous acceleration and climb speeds, and increased over the fence and touchdown speeds all make for less time to make decisions. The climb out and flare are very different from any small Cessna, Piper, Mooney or Beechcraft. You will need the Yaw Damper engaged to avoid dutch rolls. You don’t glide in with the Learjet, you fly it to the runway with an almost imperceptible flare then hold the nose wheel just off the runway until it comes down. Then slow down with full flaps, spoilers and brakes.
So is this Lionheart Creations Lear Model 24B for FSX/P3D for me?
Just like most everything else, it depends on your expectations and experiences. If you like to flight fast, fly high and fly far, and look good doing it, you will love this one. If you like to fly by the numbers, make precision approaches and fly by the book, you will love this one, provided you can find a book. If you are more casual about your flying and just like vintage jets and like to fly high and fast, and look good doing it, you will love this one. If you like to work with systems, flip switches, do detailed planning, check your fuel burn and climb rates and fly high and fast, then you will love this one. If you just want to fly around like your hair is on fire and see how fast you can get to altitude, fly for an hour or two faster than 98% of the flight simmers in the world while looking at the curvature of the Earth then this one is for you.
Generally, if you like planes that really look cool, have a timeless design, is fairly easy to fly, comes with a nice sound package and a reasonable price, then you should like this one.
If you want to fly low and slow, look at the sights out the window and count the cows, have a bright yellow paint job and brag about how big your tires are, then this one is probably not for you. LHC has a nice little TriPacer package for you.
But, does it feel good and handle like a real one?
No, not really. It does feel good to me, it feels solid, not heavy, but solid. As a real pilot that has some logged Learjet time, no it doesn’t feel quite like I remember, but neither does any of my other 50 add ons from RealAir, A2A Simulations, Milviz, Carenado and others.
What Lionheart Creations has accomplished is fairly remarkable. LHC has built us a believable replica of a 50 year old vintage corporate jet that we can fly in FSX or P3D until our little hearts are content. Not early next year, or ‘when it is ready’, but right now, today, tonight.
How about the looks, the VC, the Cabin, etc.?
The exterior is ‘knock you sock off’ gorgeous, as good as any and better than most, but at a price, 4096 texture resolution without a ‘Lite’ edition available from the factory. The eight provided liveries have all the latest bumps and shines and the interior has exotic wood trim, leather grain, and high resolution textures with lots of animations and sounds. You can even add your own music files.
The Model 24B comes with a storied history and a reputation to be maintained. I guess the logic is that if you are going to be rich and successful then you need a private jet to get you there in style and back home quickly. This one does that in spades.
Actually, you have the choice of two setups, a richly outfitted corporate jet with passengers or a super-fast cargo hauler. You also have a choice of simulators - FSX or P3D – at no extra charge.
There may be a 3rd choice in the future – an airshow edition along with an additional group of Liveries, but, we will have to wait and see about this one. No promises from LHC, just a slight possibility. I’m flying a beta version of N3137 and love it. I just added someone’s ‘trailing smoke’ to make the Airshow livery more realistic.
How does this new LHC Model 24B compare to the 20 Series Business Jets for FSX?
I do have both and can compare the two. The 20 Series from Xtreme Prototypes offers 3 models from the later models of the series – The 24, 25 and 28 models. The Model 28, the first with winglets is certified for operation at FL510. The level of detail is probably about even with one or the other having more detail in one area but less in another area.
Call level of detail a draw.
The 20 Series comes with the default GPS500 mounted in the VC panel. This installation appears to be a newer model GPS but is the default GPS500 with a new dress on. Does not allow change out to user supplied avionics like RXP or Flight1 GTNs or Mindstar.
Advantage LHC Model 24B
The 20 Series got the landing and Recognition lights correct and their lights are brighter and more realistic. Both allow Cold and Dark starts and full IFR flights with autopilot and precision approaches. Depth of systems vary with each system, with better detail present in the 20 Series Hydraulics and Pressurization, but the LHC fuel system is far superior in detail, graphics, and operation. Electric, Fire and Engines are about even.
Advantage 20 Series, mostly due to correct exterior lights and better detail and animation.
Both add ons feature a comprehensive Automatic Flight Control System and although they look slightly different the end results are probably nearly identical.
Level of immersion is a draw.
The Annunciator panel in the 20 Series is sharper and easier to read and the colors are brighter. The 20 Series AFCS annunciators use the lighted box with color to indicate active mode bit are hazy looking. The LHC uses the Airline type press to activate remote heads.
Advantage 20 Series
My impression of the overall VC is the two add ons might be equally complex or detailed, and maybe one outdoes the other in one area, but overall I give the nod to the LHC. This is primarily because the LHC approach appeals to me more as a replica of a real world Learjet whereas the 20 Series, although detailed, accurate and functional does not look like any cockpit I have ever sat in. It does not look like a real LearJet panel to me due to the panel coloring and graphics. Maybe the gauges are too clear and detailed.
Advantage LHC Model 24B
This is where the 20 Series starts to run away with the comparison. 20 Series comes with an well laid out and easy to read 84-Page Airplane Flight Manual that includes an excellent Flight Planning section with all the necessary and expected charts, tables, and instructions. This is followed by very details, accurate and easy to read checklists for Startup, flying, shutting down and emergency operation. The AFM is far superior to the LHC 35 page Owner’s Manual.
Advantage 20 Series for the Airplane Flight Manual documentation.
Now it is time for LHC to shine. The LHC package comes with full handful of useful and easy to operate 2d panels. 20 series does not have any 2d panels.
Advantage LHC for 2D panels
The LHC Model 24B uses 4096 level of external textures and, although requires a more capable PC system, obviously looks much cleaner and smoother and more detailed. The 20 Series uses 2048 x 2048 textures but are still quite sharp.
Advantage LHC for outstanding exterior textures
Comments about this comparison.
As an unbiased reviewer, I can’t come down on either side. There is not a clear cut winner between these two. The best of both worlds is to simply have both developers models in your virtual hangar. Should that not be financially viable, take your choice today and wait for a special sale for the other.
I would give high marks to the LHC Model 24B due to the support for 3rd party avionics in the VC, free P3D installer, included 2D panels, and better capture of the look and feel of the real Learjet 24 cockpit and the outstanding exterior textures. Low marks for poor documentation and exterior lighting errors.
I would give high marks to the 20 Series for the superior Airplane Flight Manual, the Flight Planning charts, tables and instructions, the detailed checklists, and inclusion of models with tip tanks and winglets. Low marks for no 2D panels, and does not replicate a real world Learjet panel.
- V1.1 Supports panel mounted GPS/GNS/GTN Avionics
- The LHC Model 24B cockpit and panel is very well built and outfitted to the late 60s with a newly added feature to trade a non-working weather radar for the default GPS500 or your own GPS/GNS in the VC with a single click.
- This is the first instance that I have seen this feature implemented. Kudos to Lionheart.
- I have the Flight1 GTN750 squeezed in as the 3rd option. This is not ideal but far superior to not having any 3rd party GNS in the VC panel and it can be popped up to the correct aspect ratio with a click on the bezel. A Reality XP GNS 530 or Mindstar unit could easily be the 3rd choice for many simmers using FSX.
I'm a huge fan of the Lear and love that I have a choice to fly with old technology or new technology. Just yesterday I tried a flight on Pilot Edge using the GTN 750 and really enjoyed it.
The 3D Virtual Cockpit is just a little short of outstanding. Probably better than Very Good. It may be better than I think it is and my graphics settings and newness to P3Dv2 is what is keeping me from giving LHC even higher marks. Now the near full-sized 2d panel is outstanding from my point of view. This is a 60% or so 2d Panel where most switches and gauges can be used for flying as well as individual popup specialty panels for fuel management, electrics, engine monitoring, audio and autopilot operation. Use the Shift + 2 thru 6 for the popups in either VC or Main panel view.
How about the features and systems?
LHC gets very high marks for both. Let’s explore the feature list first. I think the sound package deserves special mention. As most of you already know, I think the sound package is almost as important as how well it looks and flies. Crank up the volume and the bass and listen to the wind noise as the landing gear is lowered and listen to the gyros spinning. All switches have a realistic thunk sound. This one has a ton of alarms plus an overspeed alarm that I still haven’t found how to mute other than slowing the airplane down. We will talk about engine sounds a little later.
That two foot wide double row of lighted annunciators on the leading edge of the glare shield panel are all functional and some with associated sounds. The main flight instruments are big, bright and easy to read. You will be looking at the Altimeter and Vertical speed gauges are lot more than most add ons. The big HSI with glideslope and the oversized Attitude gyro will be appreciated.
The airspeed indicator is a combo analog/digital and mach meter all in one. It reads in knots which is not keeping with the vintage theme but it would screw us up if it were mph. Watch out for mph vs knots should you find an actual Airplane Flight Guide for a Model 24B. I’m sure all the flying models have been converted over somewhere along the way.
One irritating feature is the digital mach number is covered up with the back side of the needle when at high altitude cruise. I wonder if a shorter needle would work just as well and allow us to read the 0.87 mach number. Or maybe just move the mach readout box slightly to avoid being hidden by the back end of the needle.
It also has a Radar Altimeter in the lower right of the flight instruments cluster.
As I mentioned early, because Bill Lear invented the autopilot, all Lear jets came standard with a working autopilot, but, even better than that, they came with an airliner style push button remote panel. Sweet. This has been designed into our simulation.
Activate Realism – I leave that switch On all the time.
Many of the switches are 3 position switches or momentary auto reset types, all with sound effects. And there are lots of switches. The LHC Model 24B has one special switch that is very well appreciated by me, the ‘Activate Realism’ switch in the upper left of the panel. There is nothing better than realism in simulation and if can happen with the flip of a switch, all the better. I am going to leave mine in the On position.
At startup the annunciator panel looks like a Christmas tree but using the proper checklist of flow list you should be able to extinguish all the reds and yellows.
The interior lighting is controlled by adjustable knobs for cockpit, instruments and cabin. The exterior lights are typical of standard add ons. I see we have white strobes but no recognition lights.
The ramp or parking animations are all there – red remove before flight type covers, shades, engine covers, chocks and one switch on the panel to activate or deactivate them. The interior animations are also present. You can hide and unhide, or activate things with a properly placed click.
There are a couple of ‘features’ that I had just as soon turn off or not activate. One is the Bubble Placard Information System. This is a new twist on ‘Panel Layout for Dummies’ but could be useful to those that don’t or won’t read the manual, but then how would they know how to activate it (hidden clickspot). Duh. The other is an ‘In your face oversized popup’ saying “Hey, don’t land with fuel in your TipTanks”. I can certainly live without that one also, but maybe it will keep someone from bending a wing or over-stressing the landing gear one day.
I saved the best feature or system for last, and this is the highly enjoyable and well-designed Fuel Management monitoring and transfer system.
The 50 year old LearJet design is from the days when jet fuel costs 15 cents a gallon, yep that is correct, 15 cents/gal was typical of the mid 60s.
Now you remember, these engines are really just military fighter jet engines without the afterburners, so you have to carry a lot of fuel with you.
The basic design was such that the wings and fuselage would not hold enough kerosene for those two fuel guzzling engines so the designers added the Tip Tanks. Remember the original American jet, the P-80 Shooting Star with those huge wingtips tanks.
Lear Jets burn fuel from the Tip tanks, then the internal wing tanks. Once the wing tanks fuel level is sufficiently low, replenish the wing tanks from your one fuselage tank. If you have to return to the airport with full fuel then you have to dump fuel from the Tip Tanks due to the weight at the end of the arm. Otherwise you will likely cause some major structural damage to the wing. This is a full working system complete with graphics and digital meters. There are a couple of ways to dump fuel I this LHC Model 24B.
It was not uncommon to hear a line boy screaming for help when he filled one tip tank when the opposite tip tank was empty. The Lear would slowly tilt until the full tank was resting on the ground. One had to stop at about half full, go to the other side and put in ½ to ¾ of the tank then come back and fill the original tip tank. Yep, no kidding. Of course, it could easily damage the landing gear so it was improtant to make sure you either waited and watched or truly trusted the fuel boy. You also had to check the fuel levels yourself to make sure both tips did indeed get totally filled.
There are several worthy system designs in the LHC Model 24B. I like the working Wing Temp Gauge for you to monitor the fuel temperature in the high speed wing. The engine startup is well models with realistic gauge actions and readings with good sounds. I like the ‘Set Altitude’ instrument that is coupled to the autopilot that can be remote controlled with the slick remote AP switch panels. You can tell from a glance which button is activated as compared to many of the Cessna Citation or Embraer models that you don’t have a clue from looking at the buttons only.
The Model 24B has a working Yaw Damper that should be used anytime you are flying and a nifty, easy to read trim panel for all three axes. The Amp meter needles jump and move with the flip of a switch which reflects more of that realism.
I like the design of the Flaps indicator position gauge which looks and works just like the real one. You don’t have to guess what the indicator is telling you for the position of extended or retracted flaps.
I guess part of the sticking with the Vintage theme when it is convenient the Model 24B has a full ADF/DME navigation system with readout and gauges. The right panel has something named a Distance Computer that may have to do with the DME. It also as an ATC Transmitter. This is actually the Transponder.
Some systems seem to have been slighted such as the Hydraulics, Pressurization and Oxygen systems. These are mostly just dummy switches, gauges and meters. I would have thought that if we are going to spend most of our time well above the O2 level, these systems would be a bit more detailed. Any airplane that is designed to spend most of its time cruising in the Flight Levels cannot be just a bunch of flight control systems it also needs some very necessary life support systems for the crew and passengers to be comfortable way up there and especially getting back to where the oxygen is free and available should the systems fail.
I suppose the designer has to draw the line someplace or else he would never complete the model.
The Model 24B predated the use of Thrust Reversers. That came along just a few model numbers later. For the Model 24B, the standard procedure is to deploy wing mounted spoilers and full flaps in lieu of thrust reversers.
What is missing?
Not much. Enough features and systems are modeled to keep us busy and the eye candy and sounds should keep us smiling. The performance is outstanding so we can go fast, fly high, and look good doing it, just not with precision.
The flight documentation is very weak, not totally absent, just not very much model specific information. Only minimal speed and performance numbers are provided. This data is found in the General Characteristics Table from Wiki and in the Kneeboard Reference. No Takeoff and Landing tables for various weights, temperature and density altitude. No climb and distance charts to be found. Not even clean and dirty stall speeds. But, what is provided are the V1, Vr, and Vref speeds. An abbreviated Cruise Speed and Fuel Flow table can be found at the bottom of the Kneeboard.
Make sure you look around real good. There may be some checklists for performance data someplace and I overlooked it. The clipboard that pops up with F10 has an abbreviated Startup and Landing checklist but I failed to find the Pre Takeoff/Takeoff, Climb or Descent checklists. Some of the speeds are not correct in this clipboard data.
One Faux Pas
Our LHC designer got some incorrect advice and has coded the Landing Lights into the Recognition Light positions at the front of the wing Tip Tanks. This is totally wrong for all the Series 20 models as the Recog Lights are optional and are for others to see and identify you with your Nav lights sometimes hidden by the large tip tanks. Not a big deal, just not correct and looks screwy.
If you turn on the Taxi Lights then that is how the Landing Lights should look with the exception that the real Lears do not have a 3rd light on the Nose Gear Strut. One light on each of the Main Landing Gear struts only. Just don’t turn the Landing Lights Switch to the Up position and the lights will be partially correct. If correct, when the switch is in the Landing Light position they are both on full bright, when switched to the Taxi position the same two lights are used, they are just a little dimmer. Just like an auto back in the 1960s.
The LHC Model 24B Taxi and Landing lights are also disappointing in that they aren’t the newer 3D bright lights that actually work like lights and show you the way down the Taxiway or illuminate the runway when on short final. Maybe someone will come up with an add on or a tweak to the aircraft.cfg file to brighten these lights for us. When using P3D make sure you have the lighting turned on to see some interesting illumination patterns on the ground.
The installation of Recognition Lights should also require the Model 24 to carry a bit less fuel. The physical space of the lighting package inside the tip tank displaces 40 pounds of jet fuel in each tank. This should be reflected in the quantity of fuel shown on the fuel panel and the pop up digital counters. Not a big deal, just not correct in the LHC model.
It is common for real Lears to have only one Recognition Light, usually the Right Side for some unknown reason. Maybe the extra 40 pounds of fuel is useful to those folks or more likely it only takes one light for recognition. You can also check for leading edge wing ice by turning on the Recog Light (if you had one).
Look for the Kneeboard, the what? The FSX/P3D Kneeboard
Few developers put any really useful inf ormation on the Kneeboard anymore. Wrong. Lionheart Creations does and I almost missed it. I don’t remember reading anyplace in all this documentation that I will find some really useful information very specific to this model in the Kneeboard. But it is indeed there. Not nearly enough, but certainly a good start.
The Model 24B is different enough from the Model 23 and most of the Model 25s and later that data from those models would not be close enough to use even in the simulator. Because it is not a copy of an existing model we can’t seek data for the serial number or build number and the fact that it has been out of production for over 50 years and they only made less than 50 of them it is unlikely we will stumble across any useful data.
As ‘mater, the old rusty pickup in the Cars cartoon movie would say, ”I would give both lug nuts” for one look at a real Airplane Flight Manual for the 24B.
Read the Manual, even prior to purchase
The LHC Model 24B comes with a 35 page Owners Manual with loads of graphics, lists, and hints for having fun. Here is where you will find your checklists and specific dos and don’ts. Just about everything in the airplane is located and named with a series of pages with close-up images and large red pointers. A few of the instructions can spoil your day if you ignore them. Like how to shut down the engines? Simple, just turn the Jet Pumps to the Off position and starve the turbines to death. (No one was born with that piece of knowledge)
The one item that indicates you aren’t reading the manual is that your Cold and Dark Startup will not work. C & D Startup works just fine if you follow the instructions. Ignore the instructions and it might never start for you.
One of the downsides of having a manual that is prepared as a series of graphics is a spell checker will not work.
This results in at least a dozen distracting typos in the Owner’s Manual and checklists. Nothing drastic, mostly amusing misspelling like Cieling, wheel chauks, explanitory, 2 colums, placcards, useage, FL 100.
“People who own a Learjet will tell you it’s their proudest possession”
-Justin Dart, one of the first Lear jet owners
Fun things to do with the LHC Learjet 24B
You can try a Gear Up landing for some fireworks, you can push it hard with the Realism Switch On and experience an engine fire (usually accompanied by lots of yelling and screaming over the alarms and lights with more fireworks). You can get out your stop watch and see if can match the Time to Climb to Altitude record set by Neil Armstrong.
You can try various passenger and fuel loads to improve performance. You can practice short field takeoffs and landings using Ferry settings. You can also arrange the wind to be on your nose at 30 knots.
You can see how high you can fly. I heard Hank Beaird, the PIC and Lear Test Pilot for the ‘Round the World record in the Lear 24 in March 1966 say they were cruising at FL580 in some of the areas that have never heard of the FAA. I have taken mine up to FL510 so far and clocked 572 mph at mach 0.86. Make sure you are on Oxygen.
You can create a flight sim flight plan for the U.S. Speed records flying coast to coast and back to see if you can beat it. I think I read the average cruise speed for the day was 556 mph. Surely you can improve the time on the ground for refueling.
You can ignore the fuel temperature rising in the wing tanks and see if you can blow yourself to smitherings. You can also ignore the ‘in your face warning’ and land hard with full fuel in the tip tanks and see if a wing bends or breaks off.
My favorite is to use the latest v1.1 feature and add your own F1 GTN 750 and fly to the next AirVenture and park close to the A2A Simulations tent and walk over and ask Scott Gentile how his F-4 Phantom for FSX/P3D is coming along. He will probably want a tour of your LHC J24B.
4096 Only? This was the heading of a heated post in one of the support forums. Although LHC makes it very clear for everyone prior to purchase this model only comes with super HD texture levels. I think this is the first and maybe only FSX/P3D add on to come with only 4096 x 4096 textures. Yes, it does take a fairly modern PC to run smoothly but the other side of the coin is they look great. I’m sure someone will use one of the free graphic programs and render some reduced level textures for those that just must have the 2048 or 1024 texture levels. I have several add ons with both 1024 and 2048 level textures and many of them look great. A consideration for the future might be to include at a few liveries as ‘Lite’ versions with lower quality textures for those that want the add on but don’t have the horsepower for 4096 level textures.
Besides being the most beautiful airplane in the world . . . It climbs faster than any other business jet. It flies higher, It goes faster and farther. Over 500 mph, 1,800 miles non-stop plus It costs less, full quipped, ready to fly.
Cold and Dark Startups
Cold starts top the list of problems of users that just will not read the manual or explore new ways of doing things. Most users should understand by now that FSX was left unfinished when Microsoft pulled the plug and shut down the ACES Studio without warning. Their choice to use the Trike as the FSX default flight was not one of their brightest choices as the ‘default flight’ file stores twenty-two additional parameters and the Trike has almost no systems and therefore does not store systems settings needed by more complex aircraft.
Lockheed Martin may have swung the pendulum too far the other way by using the F-22 as the default aircraft for the default flight in P3D. A correctly saved file will avoid lots of headaches when you are starting up more complex aircraft. New Cold and Dark downloadable files can be found at Lionheart Creations http://www.lionheartcreations.com/LJ24B.html for those that can’t seem to get the Model 24B started using the published instructions.
I have a secret method that is 99.8% sure to work with most setups and cures many of the problems with the Cold and Dark startups.
Find the default flight with the ultralight (if in FSX) or the default flight with the F-22 (if in P3D) and 'then' switch over into the Learjet, go to your location of choice, shut down the Lear, wait for zero RPM on the turbines, and only then 'save' the flight. No other planes, only the Lear. Your Lear can now be cold started and all systems will run perfectly. (Or start up in a running flight). Guaranteed (almost)
If nothing mentioned seems to work for you can edit your last saved FLT file with Notepad and manually change the Pct Engine RPM to 0.00 and the MaxReachedEngineRPM to 0.00 and Save the file. That should fix the Cold Start problem.
Are the engines too powerful?
A few of our flight sim self-appointed experts have made comments that the N1 or RPM curve can’t be correct because they can takeoff from their favorite airport using 60% power or it is too easy to reach the overspeed condition. I hate to be the one to tell them that most of the airplanes in FSX or for that matter, those in the real world, can be flown at reduced power. Even our beloved Trike will take off with 60% power. Reaching ‘overspeed’ condition easily has always been associated with this model Learjet.
When I want to have less power I reduce the throttles, but I sure do enjoy having the power available for those high speed climbs to altitude. You need to remember these are slightly modified military jet engines without the afterburner and ‘go fast’ is a basic criteria for our Top Gun boys and girls in uniform. Or as Maverick and Goose put it – “I have the need for speed!”
Excellent Video Tutorials on YouTube
Immediately after the Model 24B was available for purchase Lionheart started posting video walkthroughs or tutorials. As of today, 3 videos are available.
Cold and Dark Startup 10:21 https://www.youtube.com/watch?v=R6c8ZFw6iTk
Fuel System Management 11:32 https://www.youtube.com/watch?v=lSThXbIExvs
Autopilot Functions 9:38 https://www.youtube.com/watch?v=lSThXbIExvs
More Information is available
Lionheart Creations has lot of screenshots and details galore at their website.
The most current info seems to be at their Facebook page.
I can’t see a good reason to post the same screenshots here that you can see at these two site.
This is not merely a new version of an old jet. It’s a new edition of a high-performance platform, available now and waiting for you to download and enjoy. I’ve inspected it, studied it, flown it, turned in inside out and upside down and even flown it straight and level to ensure that it meets or exceeds the original manufacturer standards.
Now it is ready – complete with a rich choice of liveries with matching interiors – with a downloadable Owner’s Manual that you can read in advance of purchasing. It comes with 16 specific special features outlined by the designer that are unique and required many months of extra work to accomplish.
You can take it as is or tailor it to meet your particular specifications or desires. You can use the free Paint Kit to design a new a custom livery or just change the registration number to match your initials. You can mix and match interiors, choose an executive cabin or a more basic cargo or freight hauler.
It comes with already upgraded avionics and instruments far superior to the original instrumentation when delivered in 1968. Very few aircraft had Automatic Pilots back then, but this one did thanks to Bill Lear, the inventor of the Autopilot.
It is not just fast, it is blazingly fast. As Bill Lear like to remind folks, it will climb to 10,000 feet faster than the F-100 supersonic fighter. It will climb to Fl450 without any steps along the way. It will cruise at more than 500 mph for hours and travel up to 1,600 miles. This exact model flew around the world in 1966 setting 18 world records in 50 hours.
The Smithsonian Institute’s Air & Space Magazine listed the Lear 23 as one of the top ten aircraft that changed the world.
Most important of all. It is an original Lear Jet. Yep, the very one that made the name a household word and set the standard that every bizjet manufacturer has to contend with whether large or small and whether made by Lear, Bombardier, Gulfstream or any company on earth. The original ‘Pocket Rocket’ compete with the two jet engines, needle nose, fighter wings, tip tanks and T-tail.
They only came in white, but you could paint the stripe a different color is you liked and they were all made in Wichita near the Mid Continent Airport. Just across the way from Cessna, Beech and Mooney who were all fond of saying:
The airplane will never be built,
If it is built, it will never fly.
If it flies, it will never be certified
If it is certified, it will never get delivered.
Marketing people in the Lear Jet story came from Cessna, Beech and Mooney.
Compatibility with Flight1 GTN avionics
I asked our resident GNS expert to evaluate the accuracy and correctness of navigating the LHC Lear24B with the Flight1 GTN 750 gauge installed. The quick answer is Yes, all is OK which is a little uncommon when compared to other recent complex add ons.
The stalwart Reality XP GNS series are apparently no longer supported by the longtime retailer. Those of us that have used them for years in FSX will evidently be able to continue using them in FSX but they will not work in P3D. The newly introduced Flight1 GTN series are available for both FSX and P3D and provide significant improvements in the flight sims just as the real world Garmin GTN units are far superior to the GNS 430/530 units. More Info (http://forum.avsim.net/page/index.html/_/reviews/review-gtn-650-750-avionics-r2357)
There exists a natural conflict with those flight simmers and developers that tend to want to keep the aircraft and systems, including most of the gauges, as realistic as possible to the originals and those users that immediately want to install the newest, latest and greatest new gauge or feature into a vintage aircraft.
I am not totally in either camp, but if I had to choose, I would choose the camp that wants to add the necessary gauges or avionics to make sure the vintage aircraft could be flown to an airshow half way across the country and be safe and legal or maybe to AirVenture once a year.
Having a vintage aircraft is one thing, but not being able to take advantage of the last 50 years of avionics development is asking a little much. This is the real pilot thinking coming through to my flight sim desk.
So, call me the hybrid, and I will continue to look for ways to keep both sides talking to each other and hope for something in the middle. I, for one, would love to see the F1 GTN750 installed in the VC panel with the correct aspect ratio and not squeezed to the dimensions of the default GPS500. But, like someone said, something is better than nothing and we are in the only in the position of requesting not demanding.
Back to the Future
There are many full length movies that feature at least a few minutes of prime screen time of early model Lear Jets. In Like Flint, Capricorn One, Atlas Shrugged, Part II, Airport 75, and Dragnet are a few.
My wife told me yesterday that Ayn Rand’s Atlas Shrugged – Part 3, the movie is in the news. I didn’t remember seeing Part II so I fired up NetFlix and watched the entire movie, even though I quickly realized I had indeed already seen it. Some of the scenes in Part II showed Dagny Taggart flying a Lear 23/24. Not sure which one, but it had the big oval windows. The windshield and panel was all trashy looking with different panels and futuristic looking gauges. She was flying chase to a VTOL Jet with a V tail but she crashed. A man pulls her from the wreckage. Dagny looks at his shadowed face and says with a painful voice, who are you? He answers, I’m John Galt.
Unexpected wing stall characteristics – low speed mush
I started out thinking I could find some measure of confidence in the low end speeds of the LHC LJ24B but have come to the conc lusion that any speeds below 100 knots IAS is totally absent of any flight characteristics that I recognize.
I could not stall the airplane in any flight configuration, flaps and gear up or down made no difference, accelerated stalls, takeoff and departure stalls, power off, power on, slow flight, clean or dirty, made absolutely no difference.
The airplane just goes into a mushy condition and loses altitude at an increasing rate while the nose continues to rise until it is practically vertical. The indicated airspeed is somewhere to the left side of 60 knots (the lowest number on the ASI) when anything that might be called a stall appears. Meaning a somewhat realistic rollover or quick drop of a wing . Nope, nothing like that, just a quick reversal from full nose up to full nose down and then the Lear becomes a lawn dart, heading straight to earth. This is most disappointing.
It is hard to point to pinpoint the exact problem here because we don’t know which wing design was coded into the simulation. It seems logical to me that if LHC didn’t use an Airplane Flight Manual for reference then they also most likely did not have access to specific airfoil design parameters. Lear changed the wing design with practically every early model trying to tame the violent stall characteristics of the thin wing.
What I gather from this unexpected set of tests is that any flight maneuvers requiring slow flight or speeds approaching a stall will be totally unrealistic and probably should simply be avoided.
This does not mean that you can’t enjoy flying the LHC Lear 24B on cross-country, high altitude flights, day and night and experience some terrific moments. You can explore the fuel management and fly precision approaches and non-precision approaches a and even practice some commercial flight maneuvers like lazy 8s or chandelles but don’t expect anything approaching normal at any of the really low speeds.
This should be a great platform to try to recreate some of the world records that was set back in the 1960s like the coast to coast speed records and the climb to altitude times.
And who knows, someone might come along and take an interest in the flight dynamics and do a little tweaking here and there and voila, all of a sudden, we have an even more prized possession in our hands.
But, my approaches and landings are great.
I’m going to do a series of short field landings with minimal fuel and no passengers or baggage at some known small airports and see if I can make some decent approaches with full flaps at Vref flight speeds. Even if I know the airplane will not stall maybe I can ‘fly the numbers’ and get some enjoyment by holding the proper approach speeds, attitude and rate of descent. This will also be a good test of using spoilers and full flaps in lieu of thrust reversers to slow down after touchdown.
Interestingly, the airplane feels very stable and smooth during powered descent to landings with various flap and power settings. I was pleasantly surprised. Touchdown looked very realistic with the proper attitude and hopefully the proper speed. I am eager to fly a few more approaches and landings. This is encouraging.
If you are transitioning to the Lear Jet from slower moving Cessnas, Pipers or Mooneys just remember not to flare too high or too much. Keep a little power on all the way down, peg your approach speed and see how smooth you can touch down. You never know, the passengers may still be sipping champagne.
My Second Conclusion
Maybe it is just totally unrealistic to expect a $35 FSX/P3D add on of a vintage business jet to perform perfectly throughout the whole flight envelope. After all, how many of us, and how often do we practice slow flight or stalls in a high speed twin jet designed to fly way high and way fast. Maybe I just need to concentrate on all the strong features and ignore the few weaknesses.
As far as the Landing Lights and Recognition light mix up, they are going to stay the way they are. The Developer says the system is elaborate and this would be a very involved change to make it right. I certainly can see his point of view and 80 pounds of fuel is about a minute of idle time so end of story.
The lack of performance charts and data is certainly not a new complaint, but is often requested. Flight1 and Eaglesoftdg are the exceptions and their corporate jets are based on real models with supporting fact, figures and performance data. Many of the other developers have even less data than found in the Kneeboard for this one. Disappointing, yes, a deal killer, no way.
One other point that I almost failed to mention is that the LHC 24B is the 3rd Learjet pay ware package for FSX, but the only one for P3D. There are a couple of freeware packages but they are not in the same league as these pay ware editions and they come with the default Lear45 panel.
There are some cautions if you have a low end or minimal performance PC. These 4096 textures do require some CPU oomph to get going but I didn’t notice any items that drag down the frame rates. If you are running any of the latest RealAir, Carenado, Milviz, or A2A simulations on your rig then you will probably do just fine with this one.
So, I can fly my Lear Model 24B in P3D for a very long time while telling myself that with the price of Jet Fuel closing in on the Ten Bucks a Gallon mark and at my age and without the necessary medical certificate, that this is as good as it is going to get. So stop being so damn critical and go out and enjoy yourself like the designer intended. Yeah. That sounds like a plan. Forget the details and enjoy your Lear Model 24B, I plan to do exactly that. I suggest you do the same.
Vintage Advertisements for the Learjet
We are no longer talking about Real Flight, now we are talking about Flight Simulator. But, the original Lear Jet advertisements from the late 1960s still makes sense.
The Learjet was a frequent Cover Story for Flying Magazine.
Lionheart Creations LJ24B 2D Panels
With the tendency of many developers not to include any 2D popup panels with their models, it is truly refreshing to see that LHC is not following that crowd and chose to go that extra mile.
This is especially important to those flight simmers that have cockpits or tend to fly outside the cockpit using multiple monitors. Kudos to Lionheart.
Here are images of some of the 2D panels.
For flying outside the VC, I built an additional 2D panel for my personal use so I could have one panel to monitor and control my flight. I pushed the limits a bit and took the 24B up to the really thin air. 570 mph at FL510. See image.
What’s next from Lionheart Creations?
Of course, no one knows today, but, I asked and surprisingly got a response.
Straight from the top, without any qualifications – “A four-seat prop general aviation plane, and a concept jet fighter.”
Using the basic logic that we should never expect anything if we don’t ask for it. I added my suggestion to the LHC Suggestion Box. (Thinking my choice might possibly be the concept jet fighter, or not)
I have been following the development of the ‘Secret Airplane’ jointly developed in Wichita by Textron and Airland. This looks like a mix of a miniature F-15E Strike Eagle or F-16 Eagle that could be used as a personal, modern Pocket Rocket. Using your acquired skills in developing the Model 24B Learjet along with your other futuristic designs like the Avelina and Victory VLJ this could be a game changer in FSX and P3D. I sure hope you will consider my suggestion for the Lionheart Creations Scorpion (nice ring, don’t you think?).
Book. STORMY GENIUS: The Life of Aviation’s Maverick Bill Lear By Richard Rashke
Lucky Me, Lear Story starts on page 61
Flying Magazine Archives, Google Books for most of the Vintage Advertisements.
Thanks to Bert Pieke for evaluating the GTN installation in the Model 24B.
Study Guide for Lear 24B research done by . I only isolated the 24B from the rest of the pack.
Used with permission.
Learjet 24 Operating Handbook by CAE SimuFlite, Inc, Copyright 2005, was used for some of the performance charts.
Photo credit Lear with blue stripe no ID, JetPhotos.net image be markuswillmann, incidental media use.
https://www.youtube.com/watch?feature=player_detailpage&v=REm21GGvEuk Nice early Lear Jet photos on Video
http://air.felisnox.com/view.php?name=lear2425.pdf download able Model 24/25 Reference Handbook (TS01-11)
http://www.mrmoo.net/pilot/LR25/LR25%20CockpitReferenceHandbook.pdf Learjet 25 Operating Handbook CAE SimuFlite
http://www.airplanedriver.net/study/lr20.htm Lear 24/25 Study Guide for Lear 24/25
More provided Liveries
Possible future livery for the LHC Model 24B. Almost ready, my favorite.
Procedures and Performance.
Because almost nothing is provided in the way of procedures and specific performance I have included a few pages that I gathered online from readily downloadable sources. Nothing is provided that is specific to the Model 24B but maybe the performance numbers are close enough for you until someone comes up with the real Airplane Flight Manual. Surely there is one out there someplace. The performance data is for the Model 25.