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Guest Dann

Question regarding the Cessna 182

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Hiya all, Regarding Steve's Cessna 182, when sitting at the airfield and engine off, or running at takeoff power on standard days, I cannot get the Manifold Pressure to read past the green, far below the 30" it should be reading (either at rest or generating full power).Is there a fix for this?Dan

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I flew Steve's Cessna 172, and noticed that it generated 25" of power at 6,000 feet at full throttle, compared to the 182's poor 20" at 6,000 feet. I know the 182 can generate more than mere cruise power at 6,000 feet...I spoke with a real life pilot who currently owns a Beechcraft Bonanza (amazing the similarities between his plane and FU3's Mooney...). His first aircraft was a Cessna 182, he said it's the best single engine GA aircraft made, in his opinion...and if he did it all over again, he would have kept it instead of buying the Beech.It is a shame, that we have one of the best GA aircraft available, and it's not finished! Can someone, ANYONE, tell me how to fix the manifold pressure gauge???Dan

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I'm not really helping you on this one but I've noticed that FU3 aircraft don't necessarily have the engine settings right. All of them are great for capturing the experience of flights at low altitudes -- they handle quite realistically as far as I can tell. However, the engine settings are not right, especially if you fly higher. We all know that leaning doesn't do much, except for killing the engine after a flight. A real reciprocating engine would huff and puff if you failed to lean the mixture as you ascend above 4,000 ft. I flew the Beechjet from Coupeville Nolf to San Fransisco the other day, choosing a cruise level of 25,000 ft. If anything, this is a tad low for a real bizjet going this far. Still, it required about 90% thrust (N1) to keep it at 200 - 250 kias. A more realistic thrust setting would be 50 - 65% to cruise at 250. I've noticed the same with Ansgar's B747 -- the jet model of FU3 really struggles at quite realistic cruise altitudes. Something seems to go awry as we fly high in this sim. But then, the HANDLING at low altitudes is great for most aircraft. I just focus on the airspeed and the altimeter and try to fly them by the numbers as handling is concerned, ignoring the engine read-outs.It may seem that some aircraft would do better with more power. But then, this may turn unrealistic at low altitudes where several tend towards being over-powered. If I knew how to tweak FU3 flight dynamics I might want to try more power AND a heavier load, to simulate a more powerful model with some (more) payload.best regards,Hans Petter

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Hans,I agree with most of what you are saying...regarding the Beechjet, can it really make 250 knots indicated airspeed with just 50%-60% power at 25,000? I would have thought it needed a little more...But to the point: I love the 182, and as I mentioned, a pilot whose opinions I respect called it one of the best single engine General Avaition aircraft built. As well as flight is modeled in these aircraft, half the fun is setting engine rpm's and cruise power, leaning (for what it's worth), and flying...in other words: simulating all aspects of flying as much as it can. A Flight Sim, by any other name.I am surprised, and disappointed at the lack of attention this thread is getting; it seems like nobody wants to know what the problems are. I have no doubt this little discrepancy in the 182's flight model could easily be fixed, if anyone cared about the aircraft anymore.Dan

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Hans, Considering what you said about the Beechjet's performance at 25,000 feet:"Jets typically lose about half their thrust by 25,000 ft."- Robert Shaw, "Fighter Combat, Tactics and Maneuvering."From an airspeed conversion chart , 250 knots indicated airspeed at 25,000 feet on a standard day is about 360 kias true, or 414 mph, or about Mach .55. This could not reasonably be attained by engines putting out half their sea-level thrust running at half their rpm (50%); so while 90% is perhaps just a bit too high, it would take at least 80% to 85% of the total available thrust (remember, it's only half what the engines can put out) to make over 400 miles per hour true airspeed.Tell me what you think,Dan

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I did some test flights in FS2002, first in the Beechjet converted by Chuck Dome and then in a Lear 45. I chose 75% fuel load to match what I used in FU3. I can't vouch for Dome's Beechjet flight model but the the Lear 45 is tweaked and "certified" by a flight dynamics expert.Here's what I got:The Beechjet requires 68 - 71% thrust to maintain 250 kias @ FL 250The Lear 45 requires about 70% thrustTo maintain 200 kias requires about 65% thrustThus, I seem to be partly wrong (or, partly right :-)) -- 90% thrust is way too much while my estimate of 50-something+ is too optimistic.Landing with 40% flaps and wheels down will require 50 - 60% thrust to stay on the glideslope.I forgot to add that when you state that "Jets typically lose about half their thrust by 25,000 ft.", keep in mind that they're capable of more than 300 kias at low altitudes, which is no good idea for other reasons. Put differently, you may easily attain overspeed at low altitudes -- 250 kias is no way the engine power limit.best regards,Hans Petter

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I forgot to add that when you state that "Jets typically lose about half their thrust by 25,000 ft.", keep in mind that they're capable of more than 300 kias at low altitudes,...you may easily attain overspeed at low altitudes -- 250 kias is no way the engine power limit. best regards, Hans Petter [/i]Hans, agreed regarding the overspeed at lower altitudes. The loss of power comes from the reduced atmospheric density. At sea level, where the engines are capable of putting out their full power, speeds can certainly get out of hand!Sounds like FU3 does a good job after all of modeling the higher altitudes!So, any idea why nobody wants to fix the 182? Did I raise an embarrasing question for someone?Dan

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Dan wrote:Sounds like FU3 does a good job after all of modeling the higher altitudes!Well, it's not as much off as I suspected it to be but 70% still ain't exactly the same as 90% (-:Dan wrote:So, any idea why nobody wants to fix the 182? Did I raise an embarrasing question for someone?Have we got any gauge programmers in our little community? I have no idea what it takes to add a factor / skew the reading of the gauges. I remember that Daniel (DLM) tweaked the fuel consumption of the Kingair so maybe it's a flight physics thing? Maybe adding some power reserve does it? I do share your interest in getting the flight dynamics and the engine read-outs right since these are what a flight simulator is all about. As stated above, I'm curious about the effect of adding (keeping) power and upping the load rather than lowering the the power when a model seems to be over-powered. I have no idea what Hennie did as he made some of the GA aircraft require longer runways but provided he made the engines less powerful this might affect the engine gauge reading. I repeat, since we seem to be flying empty planes, how about adding load (weight) rather than reducing the max. power? After all, most flights will include some passengers or baggage and we might tweak interior views to reflect this :-)best regards,Hans Petter

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Hans,I agree 100% about adding weight that would mimic a load; what is the point of having such outstanding aircraft if it's just you and fuel? (Virtually speaking, of course).OKAY, OUT THERE! THAT IS TWO OF US WHO WOULD LIKE TO SEE THE 182 FIXED!!! ANYONE? ANYONE?Dan

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