Dear Asobo, I am finding it impossible to tweak my turboprop engine in
accordance with real life values, real pilots are testing my upcoming M500 and
have pointed out that NG increases with altitude. I have all the data from
over 25 test flights IRL they have done, and indeed this is how the de-rated
PT6-42A works IRL. This is due to torque limiter at play, where as you climb
and the torque input drops, it takes more lever power to reach the limiter,
making NG higher as you climb. Typical example is at sea level you can achieve
1280 lbs-ft at NG% 87.5 and by the time you reach 27,000 feet ISA 0 you are at
1210 lbs-ft at NG% 94.7, and dropping the lever to 1110 lbs-ft takes you to
NG% 92.2. Since HIGH N1 and HIGH N2 max values are 100% due to CN1 being
capped at 100%, it is impossible to achieve this configuration in MSFS, this
is something that we could do very easy in FSX by setting the HIGH N1 to 117%
for example allowing us to tweak the torque tables as desired on each density,
achieving the effect without any trouble. I can see this issue is not only
affecting TurboProps but also Jets, with Alex reporting it almost 2 years ago!
(https://devsupport.flightsimulator.com/t/None) he is asking one more time
what’s the plan to address this problem here:
https://devsupport.flightsimulator.com/t/5832 This is a bigger issue for
turboprops because currently TurboProps are unable to even use N1 to N2
tables, or NE tables or anything to bypass the issue, we are pretty much stuck
with a CN1 model that cannot match the behaviour of any de-rated engine. Once
more I had no other option than code my own N2 simulation, wasting weeks and
weeks of resources to bypass this fundamental issue, however is not perfect
since I am hocking up to MSFS FM restrictions and I have to keep overriding N2
on each frame, not ideal for performance. Given the news of a new platform,
could we get this issue looked at in the future? we are striving for
excellence in our products, many aircraft manufacturers are becoming more and
more restrictive with their license terms, with many not allowing product
releases unless certain flight characteristics are able to be replicated,
therefore we need the base platform to be able to support such things. Many
thanks for taking the time to read the report and I am looking forward to see
how MSFS 2024 SDK will be able to address this issue and many other turboprop
problems I have reported that still remains unresolved today… All the best,
Raul
Important note: this also affects jets.