Another in flight adjustable question

OK... I think I might have answerd my own question, but if someone can confirm my way of thinking below, I would be grateful.

I have atached the ROTAX performance chart for Variable Prop.

So... my way of thinking.... If I am up in the cruise, I can roll on the power and coursen up the prop, as long as the manifold pressures are not above the listed requirements.

For example.... If I am in the cruise, and I wind my prop in, and the RPM drops to say 4800, and I am at full throttle, and a MAP below 26, then I should not be having any issues.

However, if MAP hits 26, I need to fine the prop up or reduce the power settings, to bring it back in line.

Fair statement - Is that it in a nutshell?

Please let me know if there is something a miss with my way of thinking.

Cheers

J

Yes, I believe that is correct.

I normally cruise at 5200 rpm and 23 in 100 kt IAS 17 l/hr

In a hurry 5300 26 inches 110 kt  23 l/hr

Max continuous 5500 rpm and 29 inches 120 kt 27 l/hr

John,

the attached Rotax chart may be a usefull guideline, too.

Regards

Peter

Thanks lads,

So the question is... seing my picture above (5380 rpm and 22in MAP) if I could course the prop up a few more notches, which would bring that RPM down to near 5000, would I get a little more IAS out of her?  MAP would probably go up a bit, but given the altitude, the ROTAX graph says that should be OK?

Thoughts?

depends on so many factors....Prop efficiency, Airframe drag curve, density and temp on the day...

Go fly and try it out...it is likely different for your plane