Ball park Hp % setting

[Mooneyjet]

Hello guys, for the lycoming 0-360-a1d. What would be a ball park manifold and rpm setting for 75% or 65% Hp. Thanks

[jetdriven]

del

[Hank]

MP + RPM/100 = 47 is 65% power. Every 3 higher or lower is another 5 or 10%.

[Bob_Belville]

65% would be about 44 (MP + RPM/100)

75% would be about 47.

 

That doesn't fit the owners manual very well at all altitudes and settings but will give you a good starting point.

[JaredDavis]

Search google using these key words

 

mooney MAPA flying by the numbers

 

download the pdf, look around page 149

 

Short answer - use at your own risk:

key number = rpm / 100 + mp

2400/ 100 = 24 + 24 mp = 48

 

46 = 65%

49 = 75%

(from MAPA doc)

 

Double check with your POH.

[Bob_Belville]

MP + RPM/100 = 47 is 65% power. Every 3 higher or lower is another 5 or 10%.

Hank, I'm looking at a '66E owners manual... @ 7500' 22/2500 is 76% and 20/2400 is 66% (21/2400 is 70%)

 

It will look a little different @ 5000' or 10,000'

[Hank]

I'm going from memory, maybe for the C model the sum = 47 is 75%, I'll have to check my MAPA notebook this evening. It is written around a 62 or 63 model, I think.

 

I normally run 45-46 depending on altitude; down low I run 23/2300; mid-level for holds, etc., generally 22/2400; and at cruise altitudes 2500 and (WOT - a bit), because I want to disengage the auto-enrichment circuit at WOT, and I want to create turbulence in the carburetor for better fuel atomization. At 10,000 msl, I may be just under 20"/2500 and indicating 130-135 mph. Not bad for 180 hp.

 

Should I find myself on one of the 2500-foot altitudes in the book, I'll use the chart directly, and I take its advice at 6500 or 9000'.

 

Don't forget temperature! The standard temp at each altitude is listed in the charts; every 10ºF above that subtract 1% power; for every 10º below that, add 1% power. So cruising at 10,000 msl using 20"/2500 should be 70% power, but if the temp is 57ºF as it was recently, 57 - 23 = 34, so it is really 70 - 3 = 67% power.

 

Having looked at the Performance Chart, I'm now thinking I had the equation wrong:

 

     MP + RPM/100 = 47 => 75% power is looking more and more correct.

 

This is a good rule of thumb when ATC is giving you step descents every few minutes. I keep cruise MP and EGT during descent, but if I have to level off then I reset [Richen up, adjust throttle, maybe subtract 100 RPM, re-lean].

[meddesign]

use the book, Owners Manual, it is different for every altitude, RPM, if you have a fuel flow, you might notice similar fuel flows for similar % bhp.  Remember the book is for ROP operation.  Use your manual.

[DaV8or]

use the book, Owners Manual, it is different for every altitude, RPM, if you have a fuel flow, you might notice similar fuel flows for similar % bhp.  Remember the book is for ROP operation.  Use your manual.

 

That's what I was wondering. What's wrong with the POH? Everything I have read including the APS and Busch articles say that the POH is the definitive source of HP info when running ROP. I created an interpolated chart showing different settings that make 65% and 75% at different altitudes. All the numbers are derived from the POH. I laminated this card and keep it with the plane.

Mooney Power Settings.pdf

[Mooneyjet]

I been trying to calibrate, the fpl5, and my poh power setting to what is reading out is completely off.

[meddesign]

I been trying to calibrate, the fpl5, and my poh power setting to what is reading out is completely off.

that is a different book, call the manufacturer if you continue to have problems, could be some of your  instruments are off.   Start with the basic listings in the POH before you get fancy. If your MP, tach, or Airspeed etc is not right you will have problems with the results.

[rbridges]

Hank, I can't remember if it's due to the prop or engine or both, but I'm supposed to keep RPM's above 2350 for continued use.  IIRC, it's based on my prop used on my specific engine.