10/23 Raptor Video

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PPLOnly

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...endless figure 8's with one eye on the hobbs and the other on the engine monitor waiting for the engine to explode...

Quite the flight test program there!
I’m still not entirely sure why he’s not getting 6-8 airborne hours in a day if the plane is running right and the weather is nice. I wonder if his nerves can’t take it.
 

Pilot Rick

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I’m still not entirely sure why he’s not getting 6-8 airborne hours in a day if the plane is running right and the weather is nice. I wonder if his nerves can’t take it.
Because after every single flight there has been some problem and something to "adjust". Maybe after he finds the right engine oil his problems will go away. That was where we were when he stopped doing the youtube videos.
 

231TC

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I’m still not entirely sure why he’s not getting 6-8 airborne hours in a day if the plane is running right and the weather is nice. I wonder if his nerves can’t take it.
It's not. He pulls back the power almost immediately after takeoff to manage heat, starting with a relatively cool mass. Can't put much fuel in the tanks so can't fly for much longer. Probably can't refuel and go right back up because after first flight the mass is good and heat soaked, and it's approaching midday so ambient is 20 degrees warmer, too. Can't takeoff at 70% power, so he parks it.

And then there are likely still frequent fixes and experiments with oil weight or whatever else he thinks of on any given day. Before this flight was a 20 minute one followed by a 3-day hiatus, so something wasn't right.
 

llemon

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Or if things keep failing he might choose to quit and install a traditional engine. Legally, he could declare victory at 15 hours and apply for a cross country flight permit. I think 40 hours engine testing program is a minimum. It should be capable of at least 20 trouble free hours before starting the airframe test program or ferry flights.
But if he does that then he can only sell people a kitplane instead of kit + engine conversion.
 

5761RF

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The above post by 231TC correctly frames the main reason why the Raptor is proving to be a total failure as a functioning aircraft. It is dependant on surface ambient temperatures below 60° F to stay airborne, and even then it cannot be operated at throttle settings above 60% for more than a few minutes.

With the advent of warmer Spring weather, the operating window for Raptor is shrinking rapidly. How Muller intends to respond remains to be seen. His fixation on flying it for 40 hours as an important goal is a self imposed target which proves absolutely nothing positive about its flight characteristics, especially considering the haphazard manner in which flight time is accomplished.

The inadequacy of the aircraft's heat rejection system is not the only issue being revealed by the flights. Inflight videos show pitch and roll instability, the severity of which is unknown because Muller has made no attempt to explore the problem during the 'test' flights. The aileron control system likely contributes to the quandary, as it has been repeatedly modified over many months of guesswork.

Actually, Muller's efforts to show progress and demonstrate Raptor's worth as a paradigm shift in personal aviation is proving to illustrate the opposite of his previously stated claims. The aircraft is.an abject failure in that regard, as @rv6ejguy revealed in a recent video.

His point by point examination of Muller's performance projections showed that the aircraft fails to meet any of the claimed specifications, and while a subsequent prototype might improve on a few of the shortcomings, others cannot be improved because the design is at fault. Muller's drag numbers, laughably enhanced by his fuselage and its Whitcomb rule influenced.waist, is a good example of this.

It's highly likely Muller's.decision to discontinue his video updates was not for the claimed reason of time constraints and his need to focus attention on completing his 40 hours of making figure eights above Valdosta's long runways. A more reasonable assumption is that he has recognized the videos show.that each hour of flight time requires days of work to correct mechanical failures and design deficiencies. This game of Whack-A-Mole is made more difficult by Muller's almost laughable interpretation of what causes the problems and how he addresses them. He has recognized that the videos have become a journal of public self flagellation, and no good can be accomplished by their continuance.

One hopes this further retraction into his protective shell does not increase his demonstrated ability to ignore warning signs and accept a normalization of deviance. His most recent videos show a man that has become noticably thinner and haggard, and the pressures he faces are weighing heavily upon him. I hope there is someone in his life to take him aside and voice these concerns about his health and well being.
 

rv6ejguy

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Tough choices here for Mueller- deliver the goods, fold or sell with a bunch of investors watching and waiting. Tremendous pressure on him now that's he's been so public with the project for so long and made so many boasts about "disrupting the market" with Raptor.

There is a good lesson here for future new designers- market AFTER your test flight program is complete and don't attempt a project like this with no previous experience in the field unless you plan to get professional help along the way- and take it of course. The Celera guys did it right. That one was all secret until the airplane was flying but of course even that route doesn't guarantee market success. Only the merits of the design, the actual market for it, combined with a real business plan gives you a fighting chance.

A Lyc, Conti or Adept turbo engine would shed at least 300 pounds on Raptor and allow a proper flight test program to continue to at least see what's possible performance wise and learn about flight characteristics to apply to a 2nd prototype if that's even in the cards. Very little useful is being learned right now which might apply to production kit aircraft.
 
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Rataplan

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Feb 14, 2021
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The variations in speed are due to flying circles with wind present. Slow upwind, fast downwind. For an hour.
Indeed forgot the shown speeds are ground speeds . with an estimated average of 130 kts and a radius of 5500 ft means turns with a bank of 15 deg. Must be boring filling the 40 hours like that LOL
 
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canardlover

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Well I talk about the Holding not a Branch , There are a lot of LLC's on her his and or Rud Taras (of the RUD AERO RA 2 carbon aerobatic plane) Lot of inactive LLC's Whatever, the RUD RA 2 looks cool on a picture but somehow that project stopped and dont know how many kits were sold or build. Perhaps only a prototype of the RA 2 and RA 3. Both were registered but deregistered Like all those LLC's . All look good designs and the RUD planes seems to be manufactured by christean eagle Somehow all nice designs what they show looks professional and they project big numbers in sales but for unknown reason after 1 prototype its quite silent

The RA 2 Acro ship is my design as well, the RA 3 was a derivative exercise taken from the RA 2 utilizing the flying surfaces with new fuselage geometry created by Mark Bettosini who does most all of the structural engineering work on my designs. The prototype ended up being built by a couple boatbuilders and fell far short of what it could have and was meant to be. If I had not been forced out by Rud it would have been on par with the likes of the Gamebird, Extra NG, and Xtreme Air/Sbach platforms. Lacking experienced and knowledgeable oversight all efforts by Rud slowly drifted off into the sunset and disappeared. He thought he could take production abroad and was purely the money side of the equation, no technical knowledge or prowess

RA 2 CAD image and early conceptual sketch of single seat variant of The RA 2 ( thus the use of whiteout on sketch and overlayed cockpit/canopy hatch area LOL.) It was to be convertible for competition to single seat canopy hatch and removable front cockpit articles (seat,etc) for weight savings. Christen had no part in the program. I generated the plugs and tooling for the 2 in house in Sebastian. The design ended up being stolen from me by Rud and subsequently sold to a Chinese concern. A friend sent me photos taken at some airport abroad with the two aircraft , RA 2 and RA 3, parked behind the tables setup for the signing ceremony
 

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canardlover

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Canton, Ga USA
Tough choices here for Mueller- deliver the goods, fold or sell with a bunch of investors watching and waiting. Tremendous pressure on him now that's he's been so public with the project for so long and made so many boasts about "disrupting the market" with Raptor.

There is a good lesson here for future new designers- market AFTER your test flight program is complete and don't attempt a project like this with no previous experience in the field unless you plan to get professional help along the way- and take it of course. The Celera guys did it right. That one was all secret until the airplane was flying but of course even that route doesn't guarantee market success. Only the merits of the design, the actual market for it, combined with a real business plan gives you a fighting chance.

A Lyc, Conti or Adept turbo engine would shed at least 300 pounds on Raptor and allow a proper flight test program to continue to at least see what's possible performance wise and learn about flight characteristics to apply to a 2nd prototype if that's even in the cards. Very little useful is being learned right now which might apply to production kit aircraft.

Ross, likely 400+ on the engine pkg alone, and enable 150 to 200 lbs of lead removed from the nose and all the associated water to air HXs and resultant heavy rubber hose plumbing. There are likely more items that could/should be removed as well ( AC, etc) which would result in a prototype weight more in line with its contemporaries and would enable valuable comparative performance analysis to the Velo XL or my Orion enabling an assessment as to its commercial viability.

Myself, and others, tried to convince him early on of the sensibility and benefits of testing with a known powerplant producing a long proven and verified amount of horsepower to then enable performance validation and comparison, but he couldn't be swayed. I'll bet he wishes he listened now.

I feel bad for him in some ways, because we all were interested in giving the project it's best chance for success at some level. Horsepower for horsepower it could never have competed with the XL ,that was clear to those of us with experience. But it did offer some positives the XL didn't possess. Unfortunately the Raptor suffers from excess borne of inexperienced initial design criteria.

Really wishing now I had the financial wherewithal to resurrect the Orion program with minor changes to make it more user friendly than either the Raptor or Velocity line. I still have one of the fuselages from which to start.
 

Rataplan

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Feb 14, 2021
Messages
131
The RA 2 Acro ship is my design as well, the RA 3 was a derivative exercise taken from the RA 2 utilizing the flying surfaces with new fuselage geometry created by Mark Bettosini who does most all of the structural engineering work on my designs. The prototype ended up being built by a couple boatbuilders and fell far short of what it could have and was meant to be. If I had not been forced out by Rud it would have been on par with the likes of the Gamebird, Extra NG, and Xtreme Air/Sbach platforms. Lacking experienced and knowledgeable oversight all efforts by Rud slowly drifted off into the sunset and disappeared. He thought he could take production abroad and was purely the money side of the equation, no technical knowledge or prowess

RA 2 CAD image and early conceptual sketch of single seat variant of The RA 2 ( thus the use of whiteout on sketch and overlayed cockpit/canopy hatch area LOL.) It was to be convertible for competition to single seat canopy hatch and removable front cockpit articles (seat,etc) for weight savings. Christen had no part in the program. I generated the plugs and tooling for the 2 in house in Sebastian. The design ended up being stolen from me by Rud and subsequently sold to a Chinese concern. A friend sent me photos taken at some airport abroad with the two aircraft , RA 2 and RA 3, parked behind the tables setup for the signing ceremony
What I suspected , the planes really look splendid . Chritian Eagle was at the FAA registered as the builder what surprised me when you talked about bootbuilders LOL I thought that can't be Christean Eagle. Sad it ended this way .
 

rv6ejguy

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Jeff, always appreciate your practical insights here. Certainly there is some market for a larger, pressurized Velocity XL type of aircraft. Guys with bucks would sign up for a pressurized XL or Orion in a heartbeat if available, to get rid of the O2 requirement.

I think many of us feel a bit bad for the whole project with so much work invested by so many, even if they were paid for that work. Anyone who did work on it wanted for it to succeed- the fruit of your labors and all. Raptor could have been so much better than it is now had PM listened to experience and reason here.
 

canardlover

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What I suspected , the planes really look splendid . Chritian Eagle was at the FAA registered as the builder what surprised me when you talked about bootbuilders LOL I thought that can't be Christean Eagle. Sad it ended this way .
Completely slipped my mind. I was tasked to find and purchase a Christen Eagle, by Rud, for us to play with. That is what you must have seen in the registry.
 

TXFlyGuy

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Apr 25, 2012
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Location
Republic of Texas
I feel better knowing Raptor is on the ground. Occasionally I'll see in real time when it's flying and I get a little tense until I know it landed safely.
Looks like some here would feel better if the plane never got off the ground again, for "safety" reasons. Maybe this would be a good thing, for all concerned.
Well, everyone except the investors.
 
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