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Raptor Composite Aircraft

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Kyle Boatright

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Putting a few pounds of weight outboard to correct a rolling tendency he noticed on a 4 second flight? Dude needs to step back and think through the problem instead of jumping in immediately with a poorly conceived fix. Airplanes fly just fine every day with minor L/R weight imbalances. In this case, I'd look at mis-rigging, torque effects, control friction, or poor wrist/stick ergonomics rather than the minor moment induced by L/R weight imbalances.
 

pictsidhe

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Putting a few pounds of weight outboard to correct a rolling tendency he noticed on a 4 second flight? Dude needs to step back and think through the problem instead of jumping in immediately with a poorly conceived fix. Airplanes fly just fine every day with minor L/R weight imbalances. In this case, I'd look at mis-rigging, torque effects, control friction, or poor wrist/stick ergonomics rather than the minor moment induced by L/R weight imbalances.
Maybe he just needed to make a video about what he had been doing since his successful flight? His fans are not going to impressed with more taxi tests.
 
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Marc Zeitlin

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Could the canard incidence be adjusted with shims?
On a composite aircraft, almost EVERYTHING can be changed/adjusted if necessary. On LE's and COZY's, I've increased the canard incidence angle (my plane included) when the elevator TE was not "in trail" at mid-CG cruise speeds. On these planes, it's a long weekend job - not really difficult. On a Velocity, it might even be easier although there are four bolted tabs instead of just two - generally on these planes, the rear tabs are removed, the incidence angle is adjusted, and the tabs are re-attached.

Now, the reason to do this was two-fold - firstly, to reduce trim drag from the elevator deflection (although that's minimal - for the GU and Roncz canards, the drag bucket is wide enough that a few degrees of elevator deflection really doesn't add substantial drag), and secondly, to increase the deep stall margin - a canard incidence angle that's too low can allow the canard to raise the nose too far with large elevator deflections, theoretically.

Now, with the Raptor, I don't remember off the top of my head how the canard is attached both fore and aft to the fuselage structure, but it's hard to imagine that it's IMPOSSIBLE to modify the incidence angle, if there was some reason to do so.

Unless the plane runs out of TE down elevator at low speeds, I'd wait to gather more information before modifying incidence angles.

I think raising the canard incidence for testing would improve the canard lift efficiency and reduce need for trim.
See above. It MIGHT reduce drag a bit, and may very well reduce trim forces, but until there's more information about elevator deflections in steady state flight at speeds from Vs to V<something a lot higher than Vs>, I think it's probably premature to change incidence angles. Just too many variables here, not the least of which are pilot techniques.
 

cblink.007

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Watched it. The winglet weight is to balance the weight over the centreline, not 'fix' dutch roll. Looks like Peter's widebody created unexpected (to Peter) lateral cg issues.

Scary sight of the video: 50lb of loose ballast under the left seat! Why is loose ballast scary? Well, if a picture is worth 1000 words, this video must be worth 100,000.

That 747 mishap was due to a jammed stabilator actuator... caused by the MRAP rolling back, out of its straps, busting through the aft pressure bulkhead and jamming the stabilator near full up. According to the investigation report, the aircraft was actually within CG limits at the time of impact, albeit barely. This accident was discussed ad nauseum while I was at American.
 

rbarnes

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Thanks. I noticed on his YouTube comments Peter is being repeatedly asked about his canard flight experience and this question remains unanswered, as far as I know.
There was a great artcl in July Kitplanes by Paul B on Velocity canard flight training

 

WonderousMountain

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It occured to me while viewing the skip video.

Raptor could install verticle shock absorbers,
And still retract from the down position. Maybe,
someone could suggest it to him?
 

cheapracer

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It would definitely break up in many crash scenarios.
I was sarcastically referring to how it's built like a tank.


Dude needs to step back and think through the problem instead of jumping in immediately with a poorly conceived fix.
Why would he start now after 5+ years of habitually jumping in?


That 747 mishap was due to a jammed stabilator actuator...
One of my race cars once stopped as it had no spark at the plugs.

A conrod went through the block, and tore off the distributor drive on it's way out.


I hope those loose ballast bags aren't the last thing on his mind.
I seen watt ya dunn there.


I just watched the latest video, 3500 lbs .... holy smoke.

He's going a bit overboard with the imbalance thing, there may have been a bit of a crosswind, the wings might not be exactly the same mirror left to right of incidence or twist ect.

The aileron control still looks soft to me.
 
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bmcj

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I don't try to surmise what someone is thinking or what someone's real motive is.

Plenty of that on TV.


BJC
Can’t we get a psychic mind reader to join HBA? It would be a great source for “What is Peter thinking?”
 
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cheapracer

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Hey, black comedies matter!
In the latest Youtube comments section, which is surprisingly critical for a change:

Concerned poster:
Secure those weights in the cabin! The last thing you want is some G's to shift those around and hit a control pedal or stick. No one likes getting hit by a 50 pound lead-shot bag while trying to pilot a prototype....

Raptor guy:
Thanks Captain Obvious!

Next Poster:
Raptor Aircraft , you are not in sales, are you?

😆
 
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