"Beast One" - the next generation Microjet

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Victor Bravo

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Pops if I still had my old AS-W20 sailplane I'd buy you an airline ticket out to California so you could fly it... just to see you take back those words :)

In fairness, the guys who have flown the low-tail and T-tail versions of the Piper Lance all strongly prefer the low-tail originals. So much so that Piper abandoned the T-tail after some period of time.

But without prop blast involved in the aerodynamics and control power... I can't understand why Scheny's little jet would be any better off with a low-tail.
 

Lendo

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Scheny, That looks to me like a smaller single seat Asso-X, - which is also European. There has been many design variants of the original Asso-X, it's hard to keep track of them all, but Blackshape Prime comes to .
George
 

RSD

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If I was going to do a jet I would look to build on the design that a company in Colorado got to test flights just before the 2009 financial crisis - I think that they might have been in Colorado. It was a tandem seat twin engine jet with (I think) twin tails - looked a bit like a mini F14 or F18. Was powered by twin Williams FJ44's but the 1600lbs thrust PBS's would be sufficient and a lot lighter. For the life of me I can't think of the name of their plane but there was video on youtube of its first test flight. A company did buy the rights and plans etc for it when the company was liquidated after not being able to raise more money during the financial crisis. it looked great, flew well...
 

rv6ejguy

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If I was going to do a jet I would look to build on the design that a company in Colorado got to test flights just before the 2009 financial crisis - I think that they might have been in Colorado. It was a tandem seat twin engine jet with (I think) twin tails - looked a bit like a mini F14 or F18. Was powered by twin Williams FJ44's but the 1600lbs thrust PBS's would be sufficient and a lot lighter. For the life of me I can't think of the name of their plane but there was video on youtube of its first test flight. A company did buy the rights and plans etc for it when the company was liquidated after not being able to raise more money during the financial crisis. it looked great, flew well...
ATG Javelin?

Was also a single engined plane called Viper, not sure what happened to that one.
 
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canardlover

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ATG Javelin?

Was also a single engined plane called Viper, not sure what happened to that one.

Ross, it was the Javelin. I was requested by the original engineering firm to quote on building the prototype back at that time. It was powered with FJ33s not 44s. Actually acquired the prototype and other assets at auction with a partner for a little over $300 K. The partner. after we split, at others advice cut it up to perform major aerodynamic configurational modifications and it will likely never fly again. In the end it would have ended up losing a lot of its original aggressive appearance in the quest for better performance. The new configuration for some reason for me brought a B-1 bomber flavor to its appearance.

1617718460874.png
 

BBerson

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Four cluster of the RC jets is about $16,000. Enough for a single seat at air shows. A guy had a four jet self launching glider at Airventure. Elliot crashed from asymmetric thrust. They need to be centerline thrust.
 

Richard Schubert

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I would love to see a "cartoon" looking single seat version of a B-70 with a 6 pack of the RC turbines...

I wonder if I can fit them on my E-racer
 

RSD

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ATG Javelin?

Was also a single engined plane called Viper, not sure what happened to that one.
Yes it was the ATG Javelin - your memory is better than mine. It got as far as undergoing test flights before the GFC hit in 2009.
1617799870690.png
 

RSD

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Ross, it was the Javelin. I was requested by the original engineering firm to quote on building the prototype back at that time. It was powered with FJ33s not 44s. Actually acquired the prototype and other assets at auction with a partner for a little over $300 K. The partner. after we split, at others advice cut it up to perform major aerodynamic configurational modifications and it will likely never fly again. In the end it would have ended up losing a lot of its original aggressive appearance in the quest for better performance. The new configuration for some reason for me brought a B-1 bomber flavor to its appearance.
What a waste! :-(
 

Pops

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Pops if I still had my old AS-W20 sailplane I'd buy you an airline ticket out to California so you could fly it... just to see you take back those words :)

In fairness, the guys who have flown the low-tail and T-tail versions of the Piper Lance all strongly prefer the low-tail originals. So much so that Piper abandoned the T-tail after some period of time.

But without prop blast involved in the aerodynamics and control power... I can't understand why Scheny's little jet would be any better off with a low-tail.
Yep, Had to fly a couple of T-tails and Piper was right in abandoning the T-tail. Have flown both the T-tail and the low-tail of the same airplane.
 

Pops

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Agree! T tails and a tractor propeller are not a good combination.

Pops, If you get a chance fly the 727 in a flight sim. Even the dutch roll is fun in a full motion sim.
Sort of like a Cessna 411 ?
 

BJC

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Yep, Had to fly a couple of T-tails and Piper was right in abandoning the T-tail. Have flown both the T-tail and the low-tail of the same airplane.
Cessna’s marketing people, in response to Piper’s marketing people, insisted on a T-tail version of the C206. Fortunately, it never went into production.


BJC
 

Scheny

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Scheny, That looks to me like a smaller single seat Asso-X, - which is also European. There has been many design variants of the original Asso-X, it's hard to keep track of them all, but Blackshape Prime comes to .
George
I looked at the Blackshape wing and fuselage and thought about copying it, but when I compared them, my design turned out to be better by quite a margin. I will look if I can find the chart again.
Four cluster of the RC jets is about $16,000. Enough for a single seat at air shows. A guy had a four jet self launching glider at Airventure. Elliot crashed from asymmetric thrust. They need to be centerline thrust.
There is a huge difference in manufacturing quality. Model engines are only good for a 50h of operation. The PBS guarantees 200h with a really conservative margin. Hopefully it will be increased in the future.
I would not use an RC engine for anything man-carrying.
 

Rhino

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Agree! T tails and a tractor propeller are not a good combination.
King Airs still seem to sell pretty well. I think it's more a matter of some implementations are better than others rather than a complete failure of the concept.
 

Scheny

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I checked now for some representative aircraft. The Piper has a tail coefficient of 0.5 rather than the 0.7 it should have. Because of this, the conventional (underdimensioned) tail works better when subject to the propstream.

A Diamond DA40 has a coefficient of 0.7, so everything is fine. Most "bad" aircraft I looked at had a low coefficient on the 0.5 side and "good" aircraft tended to be on the 0.7 side.

Nonetheless, our testpilot was very direct in telling me it has to be conventional one and it also turned out to be not that easy to create a T-tail of the very special design that I had chosen while not exceeding the length (restricted by clearance at high alpha).
 

llemon

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I looked at the Blackshape wing and fuselage and thought about copying it, but when I compared them, my design turned out to be better by quite a margin. I will look if I can find the chart again.
How did you compare them? I've been trying to find lofts for the blackshape/terra/asso but have come up empty.
 

Scheny

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How did you compare them? I've been trying to find lofts for the blackshape/terra/asso but have come up empty.
I googled every picture showing them in a 3-view (yes, not many available, but I am good in finding them) and then rebuilt them in XFLR5. Before that, I had to measure the plans in, using a CAD tool. The old Sketchup offline version was my favourite tool for this task, but has discontinued.

Not the best method, but gets it quite close.
 
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