Hi,
Whats the heaviest plane you can torque with an irvine 53 and pull out with something approaching authority?

OR

How much thrust can a irvine 53 develop and on what prop?

Cheers

About 12 lbs. with an APC 12.25x3.75. Had one on my Somethin' Extra (4.5lbs) and replaced it with an OS 46FX because I didn't need all the thrust (put it on my 6 lb Sukhoi)

Mike

thats alot of thrust

I flew a Pizazz (aprox5lbs) with a Irvine53 and 12.25x3.75, pulled it out of hover with AUThor-eye-tie...G

Well, that may be what thrusthp says, but in reality those numbers are wayyy optimistic. I had my Irvine .53 on a 6 lbs plane, so theoretically 12 lbs of thrust should give it spectacular vertical performance. It doesn't.

Don't get me wrong, the IRvine .53 is one strong motor and IMHO the best premium sport engine in this size category. Smooth transition, extremely low idle, swings big wood, and runs on 5% or no nitro all day long. However, 12lbs of thrust it does not make.

That thrust calculator program needs a little more work. Misleads a lot of folks i think.

Anyone got recomendations for a hand held scale for measuring how much your plane pulls?

But if you slap a UT muffler on it, it'll do better. I'd guess 10.

My SE is slightly over 5 lbs, and the hardest part of hovering it is throttling back enough. About 1/4 ~ 1/3 stick. As for pulling out with authority..it's a rocket. More like insane authority.

And I agree, ThrustHP is a little optimistic..say 30%?

Well, it gives 14.6 lbs as the static thrust for a 12.25 X 3.75 APC @14,700 RPM ...70% of that is..HHhhhmmm???

I got some hand held digital fish scales..I guess I could hook them on the tail..but my opinion of them is they just make liars of fishermen.

Try a digital fishscale tied to a sliding engine platform mounted on 2 HD ball-bearing drawer slides. It worked fairly well for me and was very close to friction free. One thing very important about any kind of setup like this is to make sure you tie the other end of the digital fish scale to something very very rigid so that there is absolutely no yield to absorb any thrust the engine is exerting on the line.

Thanks all,
The model its going in will weigh about 6lbs (with some luck and alot of permagrit).
So i should be able to pull out the hover but not that quickly...but fast enough to be safe.
Cheers

Would that CAP be a Glen's??!!