Raptor Composite Aircraft

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Turd Ferguson

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So I ask again, where is PM going with this and what will his exit strategy be? Anyone have a guess?
It appears continuing with flight testing is the exit strategy.

His dozens of high speed runs accomplished nothing so he moved forward to ground effect testing. Ground effect testing yielded nothing productive so he tried to take it around the pattern. The pattern flight was a fail so now he's going forward with gear retraction testing (where BTW, it's going to accelerate to 200+ kts and climb like a rocket, just from retracting the gear) Anyway, a blown engine, prop strike or gear failure on the runway will be the end and he can then cleanly exit.
 
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...looks to be over a foot, easily...
Well, I disagree about that. The camera is very close to the axis of the trailing edge, and that makes it look greater than it is. I have flapped glider wings a foot each way from neutral, and with the camera similarly located the wing would go entirely out of frame.

As for the lack of damping, that's pretty normal. In the gliders, any damping other than that from the air resistance is cause for concern because it means that something is loose.

Here we are doing a resonance check on 24-03:

That's the same glider as in this later video:

Oh, and here's an earlier, slightly less stiff version of that wing loaded to 4.4g at Vans shop. Tip deflection was 42" from neutral, almost exactly as predicted by our bending spreadsheets. This is a bit more limber than typical, but much stiffer than an ASW19 or early ASW20.
100_6460a.JPG
 
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jet guy

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Well, I disagree about that. The camera is very close to the axis of the trailing edge, and that makes it look greater than it is. I have flapped glider wings a foot each way from neutral, and with the camera similarly located the wing would go entirely out of frame.

As for the lack of damping, that's pretty normal. In the gliders, any damping other than that from the air resistance is cause for concern because it means that something is loose.

You're comparing apples to oranges. In my opinion the amount of deflection and damping in a wing of that short a span and that depth of beam is dramatically excessive and insufficient, respectively...especially with that small amount of force applied.
 

cblink.007

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Peter says he would like ideas from people on how to address some of the many problems with Raptor but he seems to only listen to other inexperienced folks from the YT comments section
A General once said to me: "If you told the lunatic running the asylum that he was crazy, would he really understand?"

Even if intended only to casually engage his audience, the optics of asking an unvetted/uneducated crowd for ideas on how to fix what undoubtedly are hazardous flying qualities on an open forum (while selectively blocking many voices of logical reason) is irresponsible at best and outright dangerous at worst. Certainly the wrong answer in the face of eager investors!

But hey, its his project. You can lead a horse to water, but...
 

Hephaestus

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I just keep hoping he makes it to an altitude the brs functions before he needs it.

Personally that's what I think the end game will be. Engine emergency, pull the chute, destroy the airframe. Sue brs.
 

BJC

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Here's an interesting master's thesis that may be of interest to some here. It's a project to design, built and test a small sailplane in the ultralight category, but designed to meet FAR 23 standards. It describes the layup schedule for wing structure and load testing for bending strength, as well as vibration testing to find modal and damping characteristics.

Structural Testing of an Ultralight UAV Composite Wing and Fuselage [PDF]

They used something like 80 strain sensors in the wing load test and also made a nice little 'wiffle tree' apparatus for spreading the load on the wing. Nineteen accelerometers were used in each wing in the vibration testing.
The student should have credited Greg Cole.


BJC
 

Speedboat100

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As I stated before I am maintaining all the available existing stats from all the sources related to Canard Type Aircraft

Take off distance over 50':
1. Cobalt Co50 = "Short to Medium"
2. Raptor = 335 m
3. Phoenix = 488 m
4. Velocity XL = 396 m
5. Velocity SE = 427 m
6. Cozy MK IV = ?
7. Cozy III = ?
8. Long-EZ = 253 m
9. VariEze = 262 m
10. Jetcruzer = 530 m

Rate of Climb m/s

1. Cobalt Co 50 = 4.2
2. Raptor = 8.1
3. Phoenix = 6.6
4. Velocity XL = 7.62
5. Velocity SE = 6.1
6. Cozy MK IV = 6.1
7. Cozy III = 4.1
8. Long EZ = 6.9
9. VariEze = 7.6
10. Jetcruzer = ?

Standard Empty Weight kg:
1. Cobalt Co50 = 708
2. Raptor = 816
3. Phoenix = ?
4. Velocity XL = 771
5. Velocity SE = 590
6. Cozy MK IV = 476
7. Cozy III = 411
8. Long-EZ = 340
9. VariEze = 265
10 Jetcruzer = 1338

Truthfully I don't see too much of a variations... Or am I wrong with my calculations? More interesting: three out of 10 listed (Raptor, Phoenix/Orion, Velocity XL) are Jeff Kerlo's design. It takes a lot of pressure still chaising that dream. Again I am not any close to be an advocate for that "The Raptor" team - just simply paying respect to their hard work and dedication.


Long Ez just 340 kg empty ...2-seater ?

Jetcruzer was a 6-seater: AASI Jetcruzer - Wikipedia

Velocity SE is a 4-seater with 560 kg empty weight: Velocity SE - Wikipedia
 
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pictsidhe

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It appears continuing with flight testing is the exit strategy.

His dozens of high speed runs accomplished nothing so he moved forward to ground effect testing. Ground effect testing yielded nothing productive so he tried to take it around the pattern. The pattern flight was a fail so now he's going forward with gear retraction testing (where BTW, it's going to accelerate to 200+ kts and climb like a rocket, just from retracting the gear) Anyway, a blown engine, prop strike or gear failure on the runway will be the end and he can then cleanly exit.
I think he'd like to get his hands on the remaining deposit money. But he probably needs a flight that neither makes viewers airsick, or ends in an emergency.
 

wwkiefer

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Thank you very much for that explanation and the diagrams! The guy who does my aero engineering said in a text yesterday, "I think the ailerons are flexing up and down because of low control stiffness and overbalance. It is coupling with the short-period pitch mode." And I was too embarrassed to admit that I didn't know what "short-period pitch mode" was. Fixted!

One thing that Peter might consider is closing the aileron control cable loop between the two outboard pulleys, and tensioning that loop up to about twice what it is now, and connecting it to the forward control circuit as shown here. That would drastically increase the stiffness of the ailerons against symmetrical deflection without overstressing the more limber parts of the system that have caused so much system flex. It's a bandaid, of course, but one that might help move his program forward.

View attachment 102894

I'll comment to this effect on the YT vid, and see how long it lasts.

Edit add: This YT vid is the basis for my rough sketch of the aileron control circuit:



--Bob K.

Edit add add: I emailed this suggestion to Peter and he responded politely.

Has anyone concidered low-pressure hydraulics instead of cables attached to an airframe that twists and flex's?
 

wwkiefer

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So where is PM going with this? It is VERY clear, and has been for quite some time, that this airplane will never become a kit or any other form of final product. PM will not find major investors who will pony up for the huge costs of taking this project forward. So I ask again, where is PM going with this and what will his exit strategy be? Anyone have a guess?
Admiting defeat is more difficult for some, I've been there as I suspect most of us have been; it's time Peter admits to himself this bird is as done as it will ever be, time to start over and learn from this.
 

cheapracer

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Yes and Peter has achieved a lot..not many has been able to climb into 500 ft with his own design.

Fact is "something that is indisputable", and your statement is indeed fact.

But facts require context to make their position in a conversation or debate relative, and in context, no notable success has been achieved at this juncture.

HAHAHAHA......anything available!!!!!
Erik in Oz.

Did I tell you about the time I tried to drink 2 bottles of Brandavino in the Mornington footy grandstand ..... teenagers ... :beer:
 

Speedboat100

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It's essentially almost identical to a Velocity except the wider width, the diesel engine and pressurization. So what would be the point of building a regular Velocity first? He hired a Velocity expert who presumably built the wings almost exactly as a Velocity anyway. He could have saved time and money by starting with a used Velocity, like Vans did on the RV-1. I doubt the sensible gradual evolving approach would have attracted deposits and the project would have ended early.
The most major apparent mistake was the complete disregard for logical weight estimation. Since he estimated the same 1800 empty weight as a Velocity even with the pressurization, so clearly no sensible weight goal was posted on the website at the beginning. The engine is the second big variable and we don't yet know how badly estimated the engine weight and performance is.
It could be they knew the weight was vastly more but simply neglected to change the web numbers. Nobody knows.


How much wider ?
 

Speedboat100

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I was very skeptical from the beginning myself. However I know how the escrow.com works. It is virtually impossible to loose your money in it. In details: The Raptor team does not have my money. Until they would deliver my order. The money is stored on escrow account. The fast delivery is in their business' interest to deliver the product soon - to get their pay back - and that explains a lot. That is why we (users-clients community) have our updates twice a week - and monitoring team's progress from the beauty and comfort of our office. Those folks are working hard - weekends and late nights are recorded daily. So - I am not advocating them - simply saying it is not any close to what we do when "Vaporware" is being created.:tired:


Are you saying they haven't collected a nickel in 5 years yet ?
 

BJC

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I thought that it would be interesting to review the very start of this epic [Jake should consider submitting it to the Guinness World Records organization] thread.

Here is what started it all:
Anyone following the YouTube videos on the construction of the prototype, 5 seat, sleek new "Raptor", 300 knots composite canard design aircraft? Looks like a Velocity. I've been watching with interest... I may abandon my a Cozy Mark IV project.

Raptor Aircraft Home
Early aspirations for success, with a flying prototype in 2016:
That is correct - the new team is in operation lead by Peter Muller of Australia/Silicon Valley baked designer - the business is relocated to KCNI (Cherokee County Regional Airport) in GA and my scientific estimate: the real prototype would be up in the air by the end of 2016. Will see.
Reassertion of confidence in the principal:
Peter is an IT guy and knows how to manage the complexity of the creation.
Further assertion of the competence of the Raptor team - with my apologies to Jeff.
Not too long ago (I guess in 2012) one of our colleagues Mr.canardlover has been discussing his project with us And the last year Silicon Valley baked designer (originally from Australia) Mr Peter Muller joined the forces with Mr canardlover (or Jeff Kerlo to be exact) for that outstanding idea. Peter is an IT guy and knows how to manage the complexity of the creation.
Statement of reality:
Not that this has ever been done in aviation - Make ridiculous performance claims, create a web site filled with computer generated pictures and take deposits from the sheep at a low introductory price only if you act quick!
Automotive Diesel power will be great:
the Raptor Diesel GT - Audi 3.0L V6 TDI is just another field of an improvement.
The Big BS stamp applied:
Software guys know absolutely nothing about project management of physical stuff you have to engineer, build, test and fly. You know, 8 bugs to solve doesn't work well if you killed 8 test-pilots.
And reasserted:
Unless you've designed, engineered, built, tested and flown a new design, you really don't have the slightest idea how much you didn't think of and how much you don't know.
And the reality lamented:
This whole project, both the big lines and the details in the video are a setup for failure. A pity, because we could use something new
... Followed by 367 pages of discussion and an aborted first flight fraught with problems.

Stay tuned for the next recap, scheduled for page 734.


BJC
 
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