It would be really interesting to see a comparison with all else equal, and measure acceleration, top speed etc.
My thoughts are that maybe the efflux speed of the standard pipes are so high that the plane can't make good use of it, much like having a propeller with to much pitch.
Trading off 10% of the exhaust speed for 10% more static thrust might not show up on the top speed?
Hey you magazine guys, that would be a great article!

Lars

Yes, there is a lot a experimentation that can be done on this subject. Comparing the higher static thrust engine using static augmentation against the set up which is optimised for thrust maintenance at hgher speeds is similar to comparing props vs jets. The prop accelerating a higher mass of air at lower velocity and vica verca for the jet, it's a simple thrust = mass x velocity equation......the engine optimised for higher exhaust velocity continues to maintain this side of the eqation at high speeds and so continues to impart thrust to the airframe.

I have a static thrust augmenting pipe in my Eurosport because the airframe is designed for the low-medium speed flight regime where thee pipes have best effect.

I think it would be interesting to experiment with a variable geometry nozzle more inline with fullsize practice.

Rob.

Today we checked our motors again at the field.Temps were at 105d.

My BVM F-86 with P-60 (170k) was 10.9lbs

Rons Euro with Titan 22lbs

Rons other Euro with XL-200 21lbs

V..

V..
So your thrust measurements are almost the same with the deviation being with the >.1 pound P 60 . which could be within the margin of error with the gauge .
semper Fi
Joe

I presume Ron has Tam's bifurcated pipes on his Euro's. I have one on my 39 lb wet Eurosport and it takes all of a P-180 to get it off the grass in 350-400 ft. My UB jumps off in about 200 ft.

That short run to the bifurcation must produce lots of turbulence there and subsequent loss of thrust. I burned a hole in my first pipe at the bifurcation after about 20 flights.

Both of my P-180's are in different planes right now, so I can can't fish scale my Euro, but I would guess at least a 10 lb loss vs a proper size and contoured straight pipe, although, I agree with Ron, the twin pipes look and sound much cooler.

Hi Tom,
Yes...bifurcated Tams pipes and tail cones on both of them, intakes too. Its crazy when you think of how much the thrust loss there is on a hot day. Ron and Wayne flew the Euros at the same time and did some fast low passes. The titan powered Euro looked faster than the XL powered one...and my P60 powered Saber faster than both of them as i easily got on Rons six and "gunned" him down.

V..

Vin,

I swooped around behind you before you knew it and hit you with a missile your sabre belongs to me baby.


Ron