The Turbine Toucan

Teller1900

Teller1900

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I saw the Turbine Toucan a while back, but the project has come a long way since then. So much so, they're planning on breaking a few time to climb records this November.

The turbine strapped to the front of this thing puts out 3,300 lbs of thrust. The entire aircraft only weights 2000lbs. That's a 1.65:1 thrust:weight ratio...enough to accelerate vertically. Indefinitely. This thing can easily do a prop stand, then fly vertically out of it. This is an even better ratio than the best fighter a/c can offer.

From The House of Rapp: "The F-15 Eagle, for example, is about 1.12:1. Even the latest and greatest generation of jets like the F-22 Raptor (at 1.26:1) and F-35 (1.22:1 with 50% fuel) can’t compare. Among aerobatic aircraft with reciprocating powerplants, only the most pumped up Sukhois and Edges approach the performance of that magical 1:1 ratio. I ran the numbers on the Pitts S-2B and was surprised to find 0.95:1, because it sure doesn’t feel that sprightly on the uplines. Maybe I need to go on a diet?"

I can't wait until this thing hits the airshow circuit.
 
Wow! There's more engine than airplane! Interesting paint job too. I wonder if you held the prop if the airplane would create the same revolutions.
 
Tristar said:
Wow! There's more engine than airplane! Interesting paint job too. I wonder if you held the prop if the airplane would create the same revolutions.
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Haha. It's probably a free turbine, so that wouldn't quite work, but I'd bet it has a roll rate that would let you negate the rotation of the prop...assuming you don't puke/pass out first.
 
Tristan, that sounds like a spin off of the treadmill discussion
 
Actually, on the free-turbines (i.e. PT6A) you CAN hold the prop during the startup sequence for a certain period of time. The problem is - letting go! There's so much force build up against the vanes that once you let go, that prop is gonna make up for lost time!
 
CJones said:
Actually, on the free-turbines (i.e. PT6A) you CAN hold the prop during the startup sequence for a certain period of time. The problem is - letting go! There's so much force build up against the vanes that once you let go, that prop is gonna make up for lost time!
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I've done that a couple times with our PT6A-67D (one of the bigger PT6s) and with a King Air (with the smaller PT6) a while back. You can hold it until about 40% N1, but that's when the prop starts to try to come out of feather, and if you wait another 4% the secondary nozzles kick in and the engine starts producing real power. I wouldn't want to have any part of me near any moving part of it after that point. That's actually an approved way to start a cold engine if it's having trouble igniting or kicking out of feather. You just have to watch the ITTs pretty close.

I did, however, get to watch a Saab 340 start its engine (the GE CT7) with a prop strap on...you could see right when it started producing power; that strap went FLYING clear over the CRJ parked next to the Saab and landed on top of a jet bridge. Good times.

You can hold a free turbine, if you want, but there's not going to be a lot of resultant torque on the aircraft...certainly not like if you hold a direct drive prop...
 
Teller1900 said:
I've done that a couple times with our PT6A-67D (one of the bigger PT6s) and with a King Air (with the smaller PT6) a while back. You can hold it until about 40% N1, but that's when the prop starts to try to come out of feather, and if you wait another 4% the secondary nozzles kick in and the engine starts producing real power. I wouldn't want to have any part of me near any moving part of it after that point. That's actually an approved way to start a cold engine if it's having trouble igniting or kicking out of feather. You just have to watch the ITTs pretty close.
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We had a few planes (crop dusters) big enough to have a secondary ignition system. You're right - once that 2nd set of nozzles kicks in, I doubt there would be any way to hold on to the prop.
 
Teller1900 said:
It is, in fact, very similar to that. But with a bigger engine. The Raven only had a 750 hp PT6A, giving it a 1.47:1 thrust:weight ratio. Just a little less than what the Turbine Toucan has to offer. Hopefully the Toucan has a better fate than the Raven did, too.
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Hmmmmm... Looked like he was using reverse on that approach and got too slow.
 
Henning said:
Hmmmmm... Looked like he was using reverse on that approach and got too slow.
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Wonder if he had a flame-out? Looks like the tail was kicking around like he knew he was screwed, but I never heard the thing even TRY to spool back up. I know it takes a while for the turbines to get power back, but I would think it would have had a chance to spool back up just a little bit.
 
CJones said:
Wonder if he had a flame-out? Looks like the tail was kicking around like he knew he was screwed, but I never heard the thing even TRY to spool back up. I know it takes a while for the turbines to get power back, but I would think it would have had a chance to spool back up just a little bit.
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IIRC he had reverse thrust in and the engine flamed out as he was trying to bring power back in. The result was spectacular.:hairraise:
 
CJones said:
Wonder if he had a flame-out? Looks like the tail was kicking around like he knew he was screwed, but I never heard the thing even TRY to spool back up. I know it takes a while for the turbines to get power back, but I would think it would have had a chance to spool back up just a little bit.
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It may very well have, he may have been relying on going nose high and spooling up to slow the descent and make a very short landing. Oh well, --it happens especially when you are performing on the edge, it all has to go right, or it goes seriously wrong. That's what the crowds pay to see, and that's why the sponsors put the money out there.
 
NC Pilot said:
IIRC he had reverse thrust in and the engine flamed out as he was trying to bring power back in. The result was spectacular.:hairraise:
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That's exactly what happened. His signature move was short t/o into half cuban, dive hard, and land exactly on the spot he took off from. In this one, unfortunately, he lost power near the top of the climb and...well, you can see the rest.
 
Teller1900 said:
That's exactly what happened. His signature move was short t/o into half cuban, dive hard, and land exactly on the spot he took off from. In this one, unfortunately, he lost power near the top of the climb and...well, you can see the rest.
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I doubt he lost power at the top of the climb, he wouldn't have done a Beta dive if he had and would have managed a safe landing. From the looks o what happened, I'd suspect the power loss would have happened between Beta and coming back up into thrust to slow the rate of descent at the bottom.
 
Henning said:
I doubt he lost power at the top of the climb, he wouldn't have done a Beta dive if he had and would have managed a safe landing. From the looks o what happened, I'd suspect the power loss would have happened between Beta and coming back up into thrust to slow the rate of descent at the bottom.
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I thought I read somewhere that it was near the top of the climb, but I suppose beta wouldn't make sense (and would be awfully hard to achieve) without the engine running. I must have read (or remembered) wrong.
 
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