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manifold and prop setting for turbulence

here where i live in albuquerque nm we get alot of turbulence because of our mountains especially in the summer. so i am always trying to stay between 130mph and 140mph indicated. 130 is the maneuvering speed. the problem i have is slowing down the airplane. i end up pulling power back the alot which leads to low manifold pressure, sometimes as low as 15inch. is there a better power and prop setting. i read you shouldn’t fly at such a low power setting. when i set the power at 20inch and 2000 rpms it flys between 150mph and 160mph. i do have the electric prop on this. any advice would be appreciated.

Model: Bonanza 35
Posted 12/17/2021 - 5 months ago
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I use 18 inches MP and 2300 RPM in my G35 for all airwork, approaches and maneuvering. Gives me 120 MPH indicated and burns 8 GPH.

Posted 12/17/2021 - 5 months ago
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On the 'straight' 35's (as listed in OP's profile), max continuous is 2050 RPM... (TCDS A-777, item 111(d))

Mike
ABS Tech Advisor

Posted 12/17/2021 - 5 months ago
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if set my manifold to 18inch how low can i lower the prop rpms

Posted 12/18/2021 - 5 months ago
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Be aware that in turbulence you may well see airspeed excursions requiring action rather than a set in stone “engine setting”. Always make the plane do what you want/need it to do. Engines are much tougher than what many choose to believe and are very unlikely to suffer from fairly large excursions in MP sometimes needed. In such a situation the airframe really takes priority. There is a reason the saying is “fly the plane” and not “fly the motor”.

Posted 12/18/2021 - 5 months ago
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The ABS online info suggests lowering landing gear in turbulence, may help with airspeed.

Posted 12/19/2021 - 5 months ago
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In reply to: Alfonso Sanchez | 12/18/2021 - 5 months ago

if set my manifold to 18inch how low can i lower the prop rpms

Per your POH's Manifold Pressure vs. RPM chart, in the Performance section, at 18 inches manifold pressure the propeller speed may be operated as low as 1800 RPM in cruise.

35 MP vs RPM.jpg - 209.2 KB

Posted 12/20/2021 - 5 months ago
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thank you for the reply, i went back and read the poh and could see that. before this plane i have only flown a 182, 210 and i never flown at cruise with that low an rpm. i also read that at 18inch of mp and 1800 with lean for cruise should get me around 7.5 gph and around 130 mph. that speed is fine with me, im flying a 75 year old aircraft and i want to take care of it for my safety and to preserve the plane. i read somewhere, if you want to go faster buy a later bonanza. dont get me wrong my plane is fast, it will do 160 mph all day long but i have to be realistic that this is an old airplane.

Posted 12/20/2021 - 5 months ago
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manifold and prop setting for turbulence