Does anyone know the formula for a ballpark calculation of engine thrust?
Say your armed with manufacturers info: H.P., rpm range, recommended prop sizes. We assume the "little" things; engine broke in, carb tuned correctly, stock muffler, good fuel mixture, etc. ...or are there just too many variables, and bench-testing the only reliable source?
Calculting thrust seems like it would be very helpful in engine selection.
thanks,
Bryan

check out my calcuator, download from propeller section at www.mvvs.nl

Yeah, try PE's. There is another one out there called ThrustHP. Useful sometimes for quick comparisons, but the thrust numbers are notoriously inaccurate.

AV8TOR

I use it the other way around. Have prop and rpm, then calculate power and thrust. Usable data can be obtained from the many discussion groups. You soon find out which manufacturers lie, and which don't.
You can use any combination or approachthough in a simplified set calculators when you scroll down on the main page. The obtained power and thrust figures have been wind tunnel tested by CA students, and were found to be within 5% on the low side.
ThrustCalc is up to 30% off (too high)

What do I need to open the file for your calculator, Pe?

Thanks,

Bill

Mickyesoft office excel

Thanks, pe. Very useful.
I appreciate all your replies. A bit of research has shown me what kind of can of worms I'm trying to open

Live and learn. One day you'l like the worms.