Hello folks,
I prefer to separate the Il-2 Sturmovik thread from the other Russian aircraft I´m
planning to build, so I´ll use this thread for it as soon as I start building it.
At the moment I´m preparing the .air file, and I seem to be having trouble with
the single speed supercharger, probably because of the information quoted in
the source I found may not be exact, or my interpretation of it may be wrong.
For non-WEP values of 47.2 inches of mercury, the model´s performance curve
tallies acceptably with specifications, even with the lower performance of
900 Hp at 16000 ft.
However, as soon as I enter the extra 6.3 in. Hg WEP boost, for the full 53.54 MP
that the supercharger gave, the model´s performance goes way above realistic
values, by more than 50 Hp at S.L. and more than 300 Hp at 16000 ft.
At 2500 ft there should be 1720 Hp at 2350 RPM, with full boost, but far too much
comes out. Then, with 47.2 in. Hg boost, I get the correct 1500 Hp, but not at
2050 RPM - that stays at 2350 RPM, but I recall it´s difficult to deal with.
At the moment I´m trying out different Boost values to see where the correct
boost-perfomance lies. Correcting WEP Boost MP to get rid of the 50 Hp difference
at low altitude, still leaves it at over 200 Hp too fast at altitude. This doesn´t sound
new, and I seem to remember something similar happening before on some older work,
and in some posts it was mentioned that a compromise must be reached.
I wonder how complicated it will get with the other Russian plane, with the 2-speed
supercharger. That will probably be even more difficult, but I´ll deal with it when
the time comes.
Anyway.... more later!
Cheers,
Aleatorylamp
Bookmarks