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Aero News Network Video - Terrible Raptor 1st Flight Review

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Voidhawk9

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Is anyone else concerned about the possible uunforeseen aerodynamic trouble looming by placing fences across the flow on surfaces without proper consideration of the consequences? Wheel-well or not, those things are going to change the aerodynamic characteristics of that part of the wing significantly.
 

pictsidhe

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Is anyone else concerned about the possible uunforeseen aerodynamic trouble looming by placing fences across the flow on surfaces without proper consideration of the consequences? Wheel-well or not, those things are going to change the aerodynamic characteristics of that part of the wing significantly.
Yes.
 

pictsidhe

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Latest YT video, Car engine just packed up, its an AUDI, bodes well for future use of this engine in an aircraft, oh its has already!!!!!!! 🙄
I've met a lot of proficient car mechanics who wouldn't consider adapting an engine for aero use. I can't think of anyone who has done an aero conversion who can't diagnose their own car problems.
 

rv6ejguy

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Is anyone else concerned about the possible uunforeseen aerodynamic trouble looming by placing fences across the flow on surfaces without proper consideration of the consequences? Wheel-well or not, those things are going to change the aerodynamic characteristics of that part of the wing significantly.
I found it amazing that anyone would even think of doing this and expecting it to achieve the stated purpose. I can't recall seeing something like this on any other aircraft.
 

Bill-Higdon

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I think a lot of pushers are in that boat. And the problem with the Raptor is not that it can't cool statically at full power, it's that it can't cool statically at idle.

Even tractor aircraft have trouble cooling on the ground, occasionally. The root section of the propeller isn't that efficient for pushing air back. That's why they use "test clubs" for ground testing rather than normal propellers.

Ron Wanttaja
The Lockheed YO-3's had a problem with ground cooling from what I've heard
 

Alessandre

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The standard power of the Audi V6 TDI is about 245 hp, then if the raptor is running bellow of this power probably all the preparation of the engine became it worst than the factory default parameters, I think change the parameters of injection and curves is only for specialists working in laboratory of the engines because I had see a lot of the preparation that only broke engines and didn't add any extra power. The best think in this situation would be he back his engine for the factory specifications.
 

Alessandre

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The "stall strip" he tested and discarded is a common device Stall strips - Wikipedia, but not necessarily for that purpose.
The best temporary solution would be he fill the hole with foam and shape the surface with the wing lower surface and make test, this fence in front of the hole is a little funny he think it will solve the turbulence issue with this solution.

I think he tried at the same time for those who never built any aircraft, it was his own design, pressurization, retractable landing gear, canard, converted car engine, if everything worked well at the first time he would be a genius above average.
 

BBerson

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I think he tried at the same time for those who never built any aircraft, it was his own design, pressurization, retractable landing gear, canard, converted car engine, if everything worked well at the first time he would be a genius above average.
He likes to experiment and said that in an early interview. Maybe he is in no rush to end the experimenting with the prototype research plane. Same for me.
He plans to tape aluminum over the wheel wells.
 

BJC

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Is anyone else concerned about the possible uunforeseen aerodynamic trouble looming by placing fences across the flow on surfaces without proper consideration of the consequences? Wheel-well or not, those things are going to change the aerodynamic characteristics of that part of the wing significantly.
Naw, doesn’t bother me any, but I don’t think that they will help any, either. ‘Course I could just be ignorant.


BJC
 

rv6ejguy

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Deposit holders have been waiting for years to get their hands on Raptor kits. I don't think Peter can afford to leisurely experiment with gut feelings and TLAR at this point. Needs some professional help in many areas if he doesn't want to spend years more getting Raptor safe to fly and performing a lot better than the first flight demonstrated.

Stall strips are usually on the wing leading edge, not lower wing surfaces and he was trying to deflect air over the wheel well with his angle pieces, not affect stall behavior. I have no idea why he thought it would actually work.
 
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BBerson

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I don't know what he was thinking either, other than he didn't want to risk taping up the hole and having it come off. Maybe behind the wheels like a small split flap would have been better.
I think I would use a faced foam sheet glued in with foam can sealant.
 

don january

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What ever he does about the LG doors he will need to add weight. I see a outer mounted swinging door that could be activated by a micro switch by the gear retracting or extending that would close the opening during flight. But what ever is done there comes the weight issue. I believe his concern of the canard AOA could be a problem also.
 

Alessandre

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Deposit holders have been waiting for years to get their hands on Raptor kits. I don't think Peter can afford to leisurely experiment with gut feelings and TLAR at this point. Needs some professional help in many areas if he doesn't want to spent years more getting Raptor safe to fly and performing a lot better than the first flight demonstrated.

Stall strips are usually on the wing leading edge, not lower wing surfaces and he was trying to deflect air over the wheel well with his angle pieces, not affect stall behavior. I have no idea why he thought it would actually work.

He thinks this situation can happens:

1603383581160.png

But I think this situation that is really happening:

1603383668536.png
 
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