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maxim26
03-10-2004, 11:44 AM
The goal is to keep the engine revolutions in the point of maximun torque that this engine can produce. I can reach it in two ways. Give full throttle and then adjust prop pitch to necessary value. Another way is to keep 100% pitch and reduce throttle. The combination of both is also a solution. Question is how to do right.

And were can i get the engine performance specifications, like the maximum revolutions, revolutions at max torque and power.

And one more question. Why I cant burn the engines of russian and american aircrufts giving full throttle and 100% pitch like german engines.

maxim26
03-10-2004, 11:44 AM
The goal is to keep the engine revolutions in the point of maximun torque that this engine can produce. I can reach it in two ways. Give full throttle and then adjust prop pitch to necessary value. Another way is to keep 100% pitch and reduce throttle. The combination of both is also a solution. Question is how to do right.

And were can i get the engine performance specifications, like the maximum revolutions, revolutions at max torque and power.

And one more question. Why I cant burn the engines of russian and american aircrufts giving full throttle and 100% pitch like german engines.

BlindHuck
03-10-2004, 12:43 PM
Maximum engine power is found at redline (unlike cars where gears/shifting require straddling peak power). Constant speed propellors set at 100% rpm should, with full throttle, produce maximum performance. I can't wrap my mind around people dropping rpm(on csp's),or throttle, to improve performance. http://ubbxforums.ubi.com/images/smiley/blink.gif

--Manual props different, no prob there.--

"I race full real exclusively in IL2:The Forgotten Battles." - Mark Donohue

BfHeFwMe
03-10-2004, 03:07 PM
Torque is never measured solely off the engine, always the prop extension shaft or in the prop gearbox itself. He's correct, the goal is keep RPM's under rated values, engines are subject to friction, and that's dependant on the speed of moving parts.

Good basic guide is your instruments themselves, notice the colored tickmarks, zones, and such, if it's red you probably shouldn't be cruising there or higher for normal flight.

German props have blade angles that are set directly in corrolation to position of the electric motor they bump with the throttle button. While a CSP takes several inputs from different sources to automatically set the best blade angle for the current flight condition. Pilot only gets a vote where he'd like the angle, he needs to understand the system in order to work it optimal. It will always work automatic and give you a result, doesn't mean it's the best it's capable of under the current input by the pilot.

You can study up a bit on props and function here,

http://www.avweb.com/news/columns/182082-1.html