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Raptor Composite Aircraft

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cblink.007

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Jul 7, 2014
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He is determined to hop this thing, which he did. Today.

Guarantee he will continue pushing....🤦‍♂️
Well, glad he hopped the nose, but as someone who has done his share of first flights, that hop looked way too aggressive...almost as if it surprised him. Just look at the control deflection. Man, I hope I am wrong. Either way, he better play it safe!
 
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Kyle Boatright

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Nov 11, 2012
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Marietta, GA
Look at the distance between the prop tips and the shadow of the prop tips.....

I can't believe he is calling that getting airborne. Skateboarders see more air than that.
I noticed the shadow thing too.

And I can get more air going over a speed bump in the parking lot.

He's crowing about doing something pointless and risky. Therefore dumb. It scares me more and more.
 

TFF

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Apr 28, 2010
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Memphis, TN
If he keeps dumping it back on the ground, he is going end up in the grass if it gets away. He is definitely not landing it; letting if fall out of ground effect and stuffing the nose over.
 

Royal

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Jun 8, 2020
Messages
71
He just needs to keep the power on and float it softly. Obviously its not taking a hard right on take off. What more is he going to figure out?
 

BBerson

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After watching the full video it does appear the mains lifted off briefly. I don't know why that tire would smoke after only a half second liftoff unless the brake was dragging.
I call it a success. He only rotated about 5°. So probably could lift off sooner with more pitch angle, but he only slightly gave some aft stick. Which was correct.
 

BBerson

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I think he said he rotated at the windsock. Is that the halfway point on the runway?
The test pilot may feel comfortable if it is still briskly accelerating at liftoff.
 

TFF

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He is playing it safe by not going fast enough. If he really has full flying speed with a soft touch down, he is at the limit of the runway and stopping. Making it hop 75-100 ft is not the same as eating up 1000 ft trying to soft flair. If he got it down before the opposite end touchdown markers, he should be able to stop. Just a little further and he is in the overrun. Extra speed and less braking distance. I’m sure the test pilots will wheelie it down way farther and will hop it if they think they have braking room. It would be worth it to blow a couple of tires doing max brake tests. Get some permission to do it on the taxiway so you don’t clog the runway with a blown tire.
 

Tiger Tim

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Apr 26, 2013
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Thunder Bay
I can't believe he is calling that getting airborne.
I can. He’s said before that once it flies he has some sort of mysterious deal that ultimately means he gets paid. Either these little hops are enough to unlock that or they may serve to show he’s on track and get another loan. Not sure if his money was budgeted as carefully as the airplanes weight (teehee) but finances have got to be pretty tight by now.
 

Victor Bravo

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Jul 30, 2014
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KWHP, Los Angeles CA, USA
I'm reminded of Howard Hughes, who was under pressure from Congress (and embarrassment in the aircraft industry) about the fact that the Hercules never flew. So he shut them up by flying it briefly..... Check-Mate.

I can easily see that some funding contract, or some investor no-money-refunded milestone clause is linked to the aircraft making its "first flight". Although I have no knowledge of this in any way, it would check a couple of the boxes that have been pointed out here. It also positions the company owner as the brave and highly skilled test pilot. (you know, without that pesky flight training or time-consuming aero-engineering degree)
 

flywheel1935

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Nov 1, 2018
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297
Location
Downham Market, Norfolk, UK.
Ok guys on this occasion I will ask a sensible question, If the wheels stop rotating at 'lift-off' so quickly then surely his brakes are dragging ?
Also the flex in the gear leg in the slow-mo looks bad. A heavy landing could prove expensive
 

wsimpso1

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Couple things.

Tapered roller bearings need a fair amount of preload to prevent edge loading. As I was taught by our mechanics, the right amount of preload is when you give the tire a good firm pull through and it stops in about 1/2 - 3/4 turn. They stop faster once the brakes are installed. I watched the slow-mo video, and the mains did not stop, but they were slowing down during the hop. Framing rate of the camera and lack of an index mark on the tire makes it impossible to tell how quickly they were changing speed... So we do not know if the wheel drag is excessive or just typical.

As for the flex in the gear, Does anyone know how springing is provided in the mains? I have been looking and not seeing it. I suspect it is just the composite leg's springiness.. If so, it is a pretty stiff leg to the landing pulse. Most of the vertical springing we see during taxi tests appears to be the tires...watching the gear during the hop and contact, vertical deflection sure looked tiny while fore-aft movement looked larger. We usually have much more vertical deflection... the fore-aft motions are driven by spin up loads during contact, and they are substantial, so I would expect some vibration in that direction. Ever watch a Cessna's wheels at touchdown? They do move all over the place under the combination of jounce and spin up loads, and that is almost entirely Wittman gear leg deflections.

After Peter's wild ride pulled some gear bushings out, I have wondered if we can expect the gear to stand a typical runway plop and stay in modest g's. FAR standard is design the gear to absorb a pretty substantial vertical speed (number is based upon wing loading) at contact and keep the g's below 3 in the process. I would sure hope that this loading case is covered in the design. If not, this is not the first time I have observed a landing gear that would not pass a drop test at regulation level sink rates.

Billski
 
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Alessandre

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May 28, 2020
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I'm surprised that at almost 80knots with the nose lifted the main quickly back to the ground with only 1 person onboard, what will be the rotate speed with 4 passengers plus lugagge? It's almost a jet.
 
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TarDevil

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I'm surprised that at almost 80knots with the nose lifted the main quickly back to the ground with only 1 person onboard, what will be the rotate speed with 4 passengers plus lugagge? It's almost a jet.
Yeah, the recent high speed activities made that Georgia runway small.
I know Justin is careful and skilled, but with that mess of an engine I hope he does that 10,000' flying over a much longer runway. I know I'm a chicken pilot, but I don't think my first Raptor landing would be on anything short as 5,000' regardless.
 

BJC

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The 5,000 foot runway should be plenty for planned takeoffs and landing. The parallel runway, 575, should be more than adequate for emergency landings during certain times. The real issue, independent of the runway length, is the inhospitable terrain off both ends of the runway, aka, the dead-Diesel-crash-zone.


BJC
 

TarDevil

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The 5,000 foot runway should be plenty for planned takeoffs and landing.
"Planned" being the operative word. I agree, once the landing characteristics are well defined. Deadsticking from altitude, I would think 5,000' may require some really precise "planning!" :eek: But I'm far from an experienced voice.
 
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