777 Service Ceiling?

[WAD3 0]

What is the highest a 777? I am flying to Heathrow and the PSS panel wants me to step climb to FL450 is this possible/usual for this aircraft and for that matter what about the 747 and 767.Thanks for any info Andrew

[Guest]

The MSFS aircraft manual shows maximum operating altitude at 43,100 for the 777. For the 747-400: 45,100. The 767 is not listed in this document. I find it hard to believe that the 777 is not capable of, at least, an equal, if not higher ceiling than the 747...but I'm no expert. Are the aircraft specs available at a Boeing site, perhaps? prowler

[Guest]

Here's something I got from an "ask a scientist" site:Question - What is the normal and maximum altitude that a commercialairline will fly? I have heard that Boeing 777's have flown at altitudesof around 40,000 ft. and wondered if this was possible for a commercialaircraft to fly at this altitude.------------------------------------------------Yes they fly at that and a little higher.Peter Faletra Ph.D.Senior Science AdvisorOffice of ScienceDepartment of Energy=========================================================Maximum altitude flown by over the US by commercial aircraft is 45,000 feet.Not all aircraft (e.g. B737) are capable of this altitude. Airlines calculatethe most economical - based on winds - altitude and request such. The military may fly higher, but they are reluctant to say to what altitude.Larry Krengel I visited the Boeing site but had no luck finding a "maximum operating altitude" for any aircraft (you would think it would be there, somewhere).

[Guest]

Boeing site doesn't list a maximum service ceiling, that I can find.this from aerospaceweb:PERFORMANCE: Max Level Speed at altitude: 575 mph (930 km/h) at 35,000 ft (10,675 m), Mach 0.87at sea level: unknowncruise speed: 560 mph (900 km/h) at 35,000 ft (10,675 m), Mach 0.84 Initial Climb Rate unknown Service Ceiling 43,100 ft (13,135 m) Range (777-200) 5,210 nm (9,650 km)(777-200ER) 7,730 nm (14,315 km)(777-200LR) 8,810 nm (16,315 km)(777-300) 5,950 nm (11,030 km) (777-300ER) 7,175 nm (13,290 km) g-Limits unknown Try the 45,000+...and see what happens?prowler

[Guest Stratus_Fractus]

767 max is 43,100 feet.

[Donstim 109]

Maximum approved altitude is 43,100 ft for the 777 and 767 and 45,100 ft for the 747. This information can be obtained from each airplane type's type certification data sheet, which is available online through the FAA' Regulatory and Guidance Library at:Regulatory and Guidance LibraryBy the way, just because the 777 is only approved to go to 43,100 feet does not mean it is physically incapable of flying higher.Don S.

[Guest tinman]

Allow me to enlighten you all :) . The max. certified altitude is set as a restriction based on flight tests carried out through the certification process for a particular aircraft type (as listed on a Type Cert. Data Sheet). This is not a manufacturer's certification, but rather one placed there by the aviation authority in that particular country, in this case the USA because of the reference to an American Data Sheet, and it says nothing about the performance capability of that particular airframe. The service ceiling of an aircraft is designated by the manufacturer, which is achieved through flight tests performed by the manufacturer during certification for a type design. This is a true measure of performance, as the definition of service ceiling is the point where an aircraft can obtain a maximum climb rate of 100fpm. So..certified alt. means nothing unless you are flying a real 777, and true performance can be found by obtaining the manufacturers service ceiling. Hope this helps.

[Guest]

It's enlightening, but in reference to original question...the plan is calling for a flight level of 45,000+...my answer would be to go ahead and try it...if the plane self-destructs then we know better . I don't know what else to say...try the flight plan altitude. prowler

[Donstim 109]

He can try flying above the maximum approved altitude, but since he will be violating an Airplane Flight Manual operating limitation, he'll be busted if the regulatory authority finds out (and they will since ATC will have the tapes)!I assume that it's the FMC in the PSS panel that is telling you to climb to 45,000+? I don't know how well their FMC matches their flight model, but if the real FMC were telling you that, it means that the airplane can get there, and that it would be more economical to fly there (based on your inputs). It doesn't mean that you have to do it, of course. I'm pretty darn sure that the FMC on the real airplane would advise you to fly above the maximum approved altitude.The maximum approved altitude is generally the maximum altitude where the pressure differential between the cabin and the outside environment is within the pressure differential that can be safely maintained by the airplane pressure vessel. Another consideration is that the airplane may not be able to descend rapidly enough to meet the standards for cabin pressure altitude after a failure (25,000 feet for 2 minutes, or 40,000 for any duration).The airplane's performance ceiling depends on thrust and lift capability. Generally accepted limits are 300 fpm rate of climb capability (as limited by engine thrust) or 0.3 g's to buffet (as limited by wing lift).

[ckukmale 27]

Even though this isnt service ceiling related whenever Ive flown on a 777 from London to New York and back our cruise height on the 777 has been 360000 going to New York and 390000 feet coming back.On 767s the height Ive been was 310000 going and 350000 coming back.Thats most of the time. One time we had to go at 280000 feet in a 767 as some equipment had failed and so the plane wasnt allowed to go over that height. I think some radar equipment had failed which meant it couldnt see the height that other planes were at during the transatlantic part of the flight when there isnt any atc to tell you about other planes in the vicinity.They used alot more fuel on that trip Im sure.Craig Kiltie

[Guest]

>Even though this isnt service ceiling related whenever Ive >flown on a 777 from London to New York and back our cruise >height on the 777 has been 360000 going to New York and >390000 feet coming back. >>On 767s the height Ive been was 310000 going and 350000 >coming back. >>Thats most of the time. One time we had to go at 280000 feet >in a 767 as some equipment had failed and so the plane wasnt >allowed to go over that height. I think some radar equipment >had failed which meant it couldnt see the height that other >planes were at during the transatlantic part of the flight >when there isnt any atc to tell you about other planes in >the vicinity. >>They used alot more fuel on that trip Im sure. >>Craig Kiltie Huh?you mean there, was something wrong with the TCAS-transponder?If that's true,I find it pretty strange that he even departed.Were was he heading from/to?about the original question,FL450 seems very unrealistic to me,maybe good for a Learjet,but certainly not for a B777.service ceiling is not equal to average cruising altitude,it's just the absolute maximum.

[ckukmale 27]

Well if I can recall it was a flight going from LHR to JFK and Im sure that was the reason as I cant think of any other reason why we wasnt allowed about 28000feet all the way till we hit Gander control.It was a piece of equipment that wasnt working and we wasnt allowed to go up above 28000feet whilst oceanic until when we got to gander we was allowed to climb so that was for the last 2 hours I guess of the flight and I cant remember what we climbed upto I think it was 34000 I think.