I wonder if zivko aviation will ever come out with a edge 720? the edge 540 hasthe 540 on as we all known because of the lycoming io 540. Now there is a lycoming io720 8 cylinder. I wonder if zivko could shoe horn one of those babiesin to a edge 540 and call it the 720. I think it could really hover!! And maybe even tail touch. Im not an expert at thrust to weight ratios tho bu i do know somethings! i might have a wuick little sketch off my computer.

Theonly way you're gonna get a 1:1 ratio is to use a turbine.

no, i bet in a few years if not now with the tech. as good as it is we will soon be seeing aerobatic planes hovering

umm turbines dont reach a 1to1 ratio in full size jets !!

The Su-31 has a 1:1 ratio so it can hang on the prop.. but a full power. Also for the turbine it would be hard to get a 1:1 on a prop airplane because of all of the extra weight. A guy put a turbo prop engine on a su-26 but it has the same preformace as with the stock engine because of the extra weight!

yep

The Lycoming 720 has been around for a long time, but it doesn't have a very good track record. It was used in a few Piper airplanes. The Brave 375, 400 Comanche, and a version of Navajo. This engine has been shoe-horned into a Pitts before I think. Now for aerobatic airplanes with greater than 1:1 power. Henry Haigh had an airplane called Rarsrepus with a Tierra Lycoming engine that had greater than 1:1 power. One of these airplane was lost due to aileron flutter. Wayne Handley had an airplane called the Turbo Raven, that could stop and go on a vertical up-line. He also used this airplane to set some time to climb records. This airplane was lost to a air-show accident, and Wayne nearly lost his life. Now for turbine engines. They are lighter weight for the same power as a piston engine, but when trying to adapt to a piston aircraft you have to have a longer nose moment or add weight for balance. Tom

very true!!

On the su-26 thing. There's actually a guy in my town, here in Missouri by the name of Dr. Ray Vetsch that has put a turbo-prop in a su-26. The turbine is lighter so they lengthened the nose. The plane fits perfectly within the "stock" weight and balance requirements. The aircraft has nearly a 2:1 thrust to weight ratio. The only aircraft more powerful on a power to weight basis is the space shuttle.

Dr. Vetsch is taking it easy with the plane right now, because some Czechoslovakian engineers are calculating what the aircraft is capable of doing safely. Also, the inverted oil system was just installed last winter. Once Dr. Vetsch gets comfortable with this aircraft, I'm sure everyone on here will know about this project.

Sweet! Now that I think about it, when I was in Melbourne, FL for college there was a guy there that put a huge turboprop in his Glasair (not the standard Allison 400HP installation either, this was something like a PT-6 700!). Takeoffs were incredible to watch. I read that he could peg his airspeed indicator in cruise.

I think it would pretty hard to get one to one is a real plane. The twin engine jet I fly is not even close. Then you have to find a pilot that has the bal** to try it.

Chris

Actually, the Turbo Raven WAS a turbine. It was basically a Giles G 202 with a Pratt and Witney PT-6 in front driving a 4 blade, reversable prop (I think it was from a King Air). It did exceed 1-1 thrust to weight (quite signifigantly I believe).

I don't think the SU 31 exceeds 1-1. Many suuposed "Hover" maneuvers are in fact high alpha attitudes, but the wings are still providing a good proportion of the lift in conjunction with the vectored thrust of the prop.

I saw an aircraft advertised (a one-off experimental) that claimed it exceeded equity using a big-block Chevy engine through a reduction box. one interesting feature was that it could mix it's elevators with its ailerons (i.e. one up one down). Has anyone tried this with a model with two servos on the elevator?

The current high end competition aircraft (full sized that is) don't quite make 1-1, but I think the next generation probably will. That will be interesting. Years ago, full sized aerobatics was greatly ahead of models. Lomcevacs date back to the sixties and torque rolls to the early seventies. Very few modellers were doing these type of figures in the eighties. Since then, the lighter wing loading and much better power to weight of models has put them ahead. It will be interesting to see if the next crop of full-sized aircraft can catch up!

Oh, and I'd LOVE to have a drive of the turbine SU 26!!!!

I ahve a video someone sent me that shows the edge torque rolling. I direct link is: http://www.geistware.com/rcmodeling/...hkosh_2002.wmv

I have always wondered why someone doesnt put an all aluminum v6 or v8 automotive race motor in an experimental aerobatic plane. Computer controlled fuel injection, electronic ignition, etc. With a gear reduction unit on a 650-800 hp engine(very mild tuning on a Chevy v8), turning a large 3 blade adjustable pitch prop would yield more than a 1-1 power-weight ratio. All up weight would have to equal or be less than a big Lyco. Adding a small radiator (similar to one used on nascar superspeedway cars) should provide adequate cooling during the short (20-30 minute) routines. Nascar engines are very stable well into the 9000 rpm range, and are very happy in the 3000-6000 rpm range when cammed right. If its experiemental, and doesnt have to be certified for GA usage, someone should definately go for it.




Check out this lil Gem of a full scale 3d plane. I sure wish Leo would be around to fly it. Maybe Sean Tucker or Jim Leroy could be conned into taking it up. You have to play the video clip on the bottom of the page.

http://www.zivko.com/EDGE/news/leo.html


Steve

Rossan is correct (I believe). Yup, the Turbo Raven was a Turbo Prop. It generated 2400 pounds of "Static Thrust" at full power. The all composite airframe (designed by Wayne Handley along side Mr. Giles) weighed just over 1800 pounds. That's about a 1.33:1 thrust to weight Ratio. It would climb vertical from a "hang on the prop" position. As far as thrust goes, a true turbine delivers alot of "Dynamic Thrust" which is like speed thrust. Props make it with pitch. An aerobat needs "Static Thrust" for prop hangs and stuff. Props do this with diameter. For a true turbine to make enough "Static Thrust" to hover, it must be huge. That's the reason for the size of the intakes on the Harrier "Jump Jet". Most turbines are not intended to create much "Static Thrust" at all. That's why a DC-9 or Lear Jet can't hover. Even most jet fighters do not have the "Static Thrust" to climb from a stationary position. They need to build up speed before a vertical climb. I also do not believe that the SU-31 has a 1:1 ratio. It's very close, but I think it falls short. I'd like to see another better than 1:1 plane. Tucker or LeRoy would be a blast in it. They are pretty gutsy with what they have now. Maybe in a few years. It won't be long...

I had a video.. someone may be able to post the URL, but Zivko had made another deisng which they'd hoped would be the new king of aeros... but i'm to believe the designed died or soemthing..... it looked awesome anyway!

Now that's just not fair. Is it on a website or something? No fair teasing!

Guys, its shown on the link i posted above. It was Leo Loudenschlager's shark design. The gang at zivko finished the plane in July of this year, and it has a double stab/double rudder arrangement. They show how the tail works in the video. It has a small movable area, to allow for precision flying, and then the whole darn elevator halves rotate up to 75-80 degrees for what would have been 3d flight.

go to www.zivko.com and click on the news tab. from the news tab, look for leo's shark. Theres pics and some background story, and a video file (.wmv) that shows the plane. The bottom half of the rudder folds over 90 degrees on landing, to allow the tailwheel room to touch. There was alot of thought and engineering done on this plane, and they describe alot of it in the article.

hmmm this thread has really progressed

the shark was sent to a museum to be stored as an exhibit!

Jim Leroy's pitts "Bulldog" has the IO-720 I believe. I saw this motor at Oshkosh this year and it is HUGE but looks incedibly heavy. As for the shark I also saw it at Oshkosh and he said it is incapable of flying inverted because of the motor. I believe to get more power the IO540's or IO580's as seen on the Cap 232's will be hoped up more to get more power and still save weight, and I'm talking alot of weigh. Sean Tucker's challenger putts out near 400 hp he told me! I still believe there is room for improvement. The same way little 3.2 liter Toyota Supra motors put ouf 800 HP.
I say leave the IO720 for a Grumman Widgeon upgrade.

-Kelly

How bout a 3W 150 QS?

Right Thrust, I think Jim Leroy's airplane has a IO-520. As for the Shark you seen at Oshkosh it is the same airplane talked about above in this thread, it is a Suhkoi with a turbine engine. Leo's Shark by Zivko is a different airplane. Tom

I know of a guy (Marcus Schrinker) who sent his stock engine from his 300L (IO 540 i think) to a guy who does a port polish, re balences it, and does a bunch of other small things to bring the HP from 330 to 500. I saw it fly.....unlimited vertical. He didn't do any hovering because he was a fairly new pilot. He doesn't fly anymore because he said he has seen to many people die flying airshows. I dont know if what he said about 500 HP is true or not, im just going by what he said. I don't really believe it though.

I can't believe pilots like Tucker, Chapmann, LeRoy, Wagstaff, Chambliss, and Goulian (all big name sponsored pilots) do not have the most power that a Lycoming can reliabily produce. Not that it's impossible, it's just improbable. IMO Maybe it's the reliable part that scared him out of flying it. Discretion is the greater part of valor I guess.