Description of the issue:
Plane engine runs out of power and cannot climb above approximately 10,000-11,000 ft without leaning. For a turbocharged engine, this is inaccurate, and the POH states to keep the mixture full rich during climb.
If applicable, which aircraft is experiencing this issue:
Cessna 400 Corvalis
[PC Only] Did you remove all your community mods/add-ons? If yes, are you still experiencing the issue?
Yes
FREQUENCY OF ISSUE
How often does this occur for you (Example: Just once, every time on sim load, intermittently)?
Every flight
REPRODUCTION STEPS
Please list clear steps you took in order to help our test team reproduce the same issue:
Open a free-flight with the Cessna 400
Climb at Vy (110 kts) with full throttle, full RPM, and full rich mixture
You won’t be able to climb above approximately 11,000 feet.
LEAN the mixture at this point, and you’ll notice a big boost in engine power and you’ll be able to continue climbing.
YOUR SETTINGS
If the issue still occurs with no mods and add-ons, please continue to report your issue. If not, please move this post to the User Support Hub.
What peripherals are you using, if relevant: N/A
[PC Only] Are you using Developer Mode or have you made any changes to it? No
[PC, MSFS 2020 Only] Are you using DX11 or DX12? MSFS 2024
[PC Only] What GPU (Graphics Card) do you use? RTX 4080
[PC Only] What other relevant PC specs can you share? N/A
Unfortunately this is an impossible fix as the encrypted aircraft files makes it impossible to make the required edits.
As a former owner of a real life turbocharged aircraft (Turbo Cessna 210), I find the failure to realistically model turbocharged engine behaviour enormously frustrating. Flying that aircraft was such a pleasure as you set the manifold pressure and RPM and forgot about the engine until you get to cruise altitude.
What is especially frustrating with the Corvallis is that they had to kludge engine behaviour to get it to “work” this way as what they modelled makes no logical sense whatsoever. They keep the manifold pressure constant (that at least is good) and then they go and build in an RPM reduction to simulate power loss… in an aircraft with a constant speed prop!
VERY disappointing and something I really, really hope they fix soon.
After an almost 6 month hiatusI tried this aircraft again today. Sad news: no change, no improvement. The engine operation modeling is still completely inaccurate. It is also still incomprehensible to me what they actually had in mind when creating the engine performance model as it does not conform to any concept of internal combustion engine and constant speed propeller theory that I am aware of.
Very sad: I will try again in another 6 months’ time.
Currently trying to fly this myself. I managed to Zoom climb to 12,000 ft but I’m struggling to maintain just over 90 kts without the engine RPM going past 2400
The Corvallis POH states “Climbing at speeds above 115 KIAS is preferable” and “It is recommended to use full throttle and 2600 RPM in climb because this setting provides the engine with extra fuel for cooling at the slower airspeeds.”
If you were trying to climb the way the POH describes, or even with a bit more conservative 33" MP and 2500 RPM, the MP, RPM and fuel flow are supposed to remain constant up to around 18,000ft. Per the POH “The engine’s turbochargers keep manifold pressure constant from MSL to approximately 18,000ft”
HOWEVER
In the sim you will find that, once set after takeoff and the climb power reduction, the MP stays constant due to the turbochargers. This is good. The RPMs stay constant due to the constant speed prop. Also good. And the airspeed stays constant, as managed via the AP FLC setting. Still good.
However, you will notice that as you climb, the rate of climb starts dropping rather precipitously. The first time I saw this I was completely flummoxed: how could this be? But, absent anything logical/sensible to do, I tried leaning the engine… and the rate of climb very quickly increased! And for as long as I kept climbing, I had to repeat leaning every so often to maintain a decent rate of climb.
This makes no sense whatsoever and defies physics. But that is how the aircraft is modelled. And in spite of this glaring error, this issue is not even feedback logged yet! I honestly and truly do not understand why this is not recognised as it really is an awful logic mistake.
This has been bugged since the first turbocharged aircraft for MSFS2020 came out, and I’m very disappointed to hear it still hasn’t been fixed. It’s a shame that excellent mod that addresses the issue (for specific aircraft only, unfortunately) hasn’t been updated in 3 years…
This seems to be one of those bugs that very few people care about, as shown by the “massive” total of 9 votes. I find it sad as I would otherwise have liked to use this aircraft more but I just find it too frustrating in its current state.