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Barnstorm
July 4th, 2011, 13:43
I have my flight model set to 95%. As in OFF, I am used to manually adj the fuel/air mix; but does the "prop RPM" control perform the same function as the variable pitch props? And if so, is that a commonly 'controlled' function in the A2A A/C? Also, does anybody manually contrl the magnetos? The level of detail in these flight mods can be overwhelming...trying to discern which controls/flight surfaces are best accessed via HOTAS keys.

johannesl
July 5th, 2011, 22:01
In fixed pitch aircraft you will adjust the RPM with throttle, but in variable pitch aircraft your concern should be directed more to the Manifold Pressure gauge. As for magnetos the only time to mess with them is to check for a bad one on runup or, if a problem is suspected in flight, otherwise leave them on Both.

Barnstorm
July 6th, 2011, 12:09
Thanks for the reply, johannesl. I have been flying WWI flight mods almost exclusively for several months and just recently have gotten back into WWII A/C. Is there an adjustment/setting for the variable pitch props in the 1% history flight mods in CFS3? And if so, is it "worht" manually messing with?

Thanks for the insight.

johannesl
July 6th, 2011, 18:29
If you have a throttle quadrant you can go to the Control Options page and choose Axis Commands to assign the throttle, mixture, and prop. Others may have a different opinion but I just assign the throttle and on realism setting use auto mixture. In a dogfight changing the prop didn't seem to make much difference. On the other hand using a lower power setting in cruise with a coarser prop setting should give you longer range at a reasonable speed. If you want to fly a real mission profile you could make the assignments and then try to use real world take-off, climb, cruise, decent and landing power settings. You can try it and see how it goes on a short fighter sweep over the Channel. Sorry I haven't tried this myself, the "X" key is too tempting when I don't have a lot of time.

Barnstorm
July 8th, 2011, 15:30
Yeah, I understand. The Folks at A/V History due such a great job of modeling flight characteristics, and w/so many options, sometimes I tend to get lost in the "weeds" with the realisms stuff. Thanks again for the response.

fliger747
July 8th, 2011, 16:14
Constant speed props: These seem to garner a lot of misunderstanding. The prop tables in the air file and the basic parameters in the cfg file determine how the prop behaves. The cfg file entries set the limits more or less, entries controll the RPM range, typically 1200-1400 at the low end to 2700-3000 RPM as a max for most WWII piston engines. The max and min blade angles can be specified, which typically run something like 15-65 degrees with a feather Angle also specified if it is a feathering prop.

The prop will change it's pitch to maintain the load on the engine such as to keep a constant RPM without regard to the HP being developed. The MP value is the best power setting instrument, however a matching RPM should be set for best efficency. High RPM wears out the engine and is not fuel efficent. For cruise a lowish RPM will be set, with a matching moderate MP value. For takeoff usually max RPM is set and when climb power is made, first the MP will be reduced, then the RPM. The idea is to avoid having too much MP in a low RPM situation, which can result in cylinders flying out of the cowling etc.

CHT is not perfectly modeled in the FS series and seems to be much related to RPM and not as much to MP.

Increasing power, move RPM up first, then MP. For combat select either takeoff power (full RPM and rated mil MP) or max continouous power, which may have a slightly lower rpm and MP values. In a tight situation, WEP is available in some aircraft for a short time.

Good luck! T

Barnstorm
July 8th, 2011, 16:59
fliger747,
Great explanation, thanks. I was just curious if these manual controls are worth messing with anyhow. I am used to +/- the fuel mix from flying in OFF, but adding the prop +/- to match the MP seems like slitting hairs for ? power increase with WEP avail. Your thoughts?