10/23 Raptor Video

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TFF

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Apr 28, 2010
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Memphis, TN
I remember going to see the bridge at Lake Havasu, years ago, but I was more interested in a blown 460 Ford Jet boat docked near by.
 

Tom Nalevanko

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Oct 10, 2007
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Alpine, WY
The Wrights were true pioneers, nobody before them did what they did. Peter isn't pioneering much of anything here. Several homespun automotive diesels have been flying successfully in Europe for well over a decade, hundreds of belt redrives for more than 2 decades, canard aircraft for over 100 years, pressurized aircraft for 80 years, I could go on.

The thing with Peter is, he hasn't learned much from all these previous airplanes and designs, thinking he is smarter than all these other people before him, even though he had no previous experience. We call that hubris or DK. Watch his Oshkosh presentation way back on YT, it was all wishful thinking by someone with stars in his eyes at best or complete nonsense to those who've been there before him on similar projects.

I've admired his tenacity and yes, he is flying Raptor and that is quite an accomplishment but it falls FAR short of meeting his lofty projections or even being a practical airplane as it sits. It weighs TWICE as much as his original projection back in 2013. This isn't a one-off for personal use, it was designed to be a production kit for the masses- huge difference there.

It won't come anywhere close to the performance of a 20 year old Lancair IV-P in any area- speed, ROC, TO distance, useful load, ceiling, fuel burn or range. The IV-P was the existing target to beat.

He's spent over 2 million dollars, 8 years and at least 20,000 man hours getting to this point. Most of us here don't find that too impressive given the demonstrated performance to date- hardly the world beating performance he was promising many years ago.

Yes, he and a big team of people got it built and that may be enough to claim victory for some folks but the fact is it's a one person aircraft with 15 gallons of fuel aboard.

This design has a very long ways to go (and a second prototype) before it may prove itself to be worthy of production.
I never saw the big team... Are 3 or 4 people a big team? Thanks
Tom
I
 

Voidhawk9

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Mar 26, 2012
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Timaru, NZ
He's assuming the best possible reason for the turbo momentary spooldown. It's talking to him, he isn't listening.

Surely even if it was carbon deposits clearing out, then enough of it to jam the turbo warrants something more than just running it a bit more?!
 

PPLOnly

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Dec 12, 2020
Messages
123
So he didn’t even disassemble, inspect, clean this engine? Didn’t have the turbos rebuilt? And is using a low grade oil cooler? Maybe his California investors are secretly invested in an insurance policy...
 

wsimpso1

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Oct 18, 2003
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Saline Michigan
I see and hear some TV at 1:36, 3:19 and 4:48.

Would take a big piece of "crud" to jam the turbo. I think something else was up there...

Checking the turbo would be an excellent idea but that would be a lot of trouble...
There was a strong feedback between the engine and some spot on the left wing, both going up and down through a particular rpm band twice. When the engine was at full rpm, the other wingtip also vibrated big time.

Sounds to me like either two vibration modes or the same one at one rpm and at twice that rpm too. Definitely a resonance, but the camera on the other wingtip did not seem to go through the same resonance, but then we only saw it run through the range once on that side. A lot of possibles, certainly worth running again with the camera mounted differently so you can eliminate the mounting and perhaps identify a vibration mode and a couple resonances between powerplant and wings. Separate cameras on tripods looking down the trailing edges would show a lot. Might be a resonance in the rotating parts fed back to the airframe, might be resonance between engine block and airframe fed through a mount, might be a resonance between prop shaft case and airframe. Gotta look to find out...

Usually when some individual thing takes off at particular forcing function speeds, the vibrating elements are in resonance where the frequency coincides with the forcing function, but it can happen other ways too. Whatever it is, it has a strong possibility to break something, and ought to be chased down. It might be something easily fixed, like some part of the engine bearing on the airframe or a mount grounding instead of isolating. But someone has to investigate, find the issue, and then figure out if it is dangerous or not.

Then there is the issue of engine being run with something either stopping or severely slowing the turbo spool. I am suspicious that something interfered, but without taking a good look at both turbos and their wastegates, we do no know what happened, how long before we can expect it to repeat, or how long before the turbos come apart and trash another engine... Another topic for a more serious investigation before attempting to run it some more. It will usually take an awful big chunk of crud in the exhaust path to stop a turbine/compressor wheel set, and that will leave its mark on the turbine and housing. But some ash in the lube/cooling path to the shaft might do it and leave its mark on the shaft and bearings, and then end up blocking the drain tube or loosened the bearings to the point where it will all come apart later. Again, it has to be investigated, issue found, and then assessed.

Checking the turbo, the oil paths to and from the turbos, and perhaps the wastegates too might make all kinds of sense. Knowing what is making the wing tips shake makes all kinds of sense too. Whatever did those things and made all the noises that came with both events is really good practice. Skipping the investigations might well mean another in-flight emergency or two.

Billski
 

Geraldc

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Nov 12, 2011
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547
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nz
My possible solution would be to scrap both turbos and fit one compatible one.
I know Peter spends as much time on here as we do.
Peter?
 

Pilot Rick

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Jan 4, 2021
Messages
33
Skipping the investigations might well mean another in-flight emergency or two.
Hasn't just about every flight been an in-flight emergency? Instead of doing what you recommended his plan is to run the engine on the ground and listen for funny noises. The failure of the turbo probably did not make a funny noise so as he says "he's good with it".
 

Voidhawk9

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Mar 26, 2012
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517
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Timaru, NZ
Hasn't just about every flight been an in-flight emergency?
No. He has had a fair number of flights that went according to his plan, most of them even. Though many would disagree with what his plans are, he nonetheless has achieved many of those plans.
The failure of the turbo probably did not make a funny noise so as he says "he's good with it".
He indicated that it made a squealing sound briefly. More evidence it is likely a bearing issue?
 

5761RF

Member
Joined
Nov 26, 2020
Messages
19
The resonant wing vibration as the throttle was pushed up was significant, to say the least. Something about the new engine or its installation is causing it. One would think the operator might be curious about the source. His explanation for the turbocharger aberration is another in a long series of almost crackpot hypotheses.
 
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