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Raptor - 300kts, 130k usd, 7gph jet-a1

I think it’s the engine that will get him into trouble eventually. I don’t have the technological background to understand it all but there seems to be a concensus on several fora that his redrive is a big no-no. The lack of a backup ECU is another one…

EBST, Belgium

Belt redrives have been around for a long time on auto conversions – the issue here being that it is of his own design and not a proven model with history, the dual ecu is a bit of a red herring.
Back in the dark ages (1950s) mechanical ignition systems (magnetos) were prone to failure so I can understand why there was a requirement for dual ignition systems on aircraft engines (never mind the single point of failure injections systems of course) which has led to all aircraft engines must have dual ecu’s mindset –
This is not a certified plane, I would say that for a prototype airframe the chances of a ECU failure given how much he has run the engine and its current install are miniscule – if he is going to develop this further then a dual ECU architecture and a more solid redrive implementation needs to be part of the development plan – lets see if the airframe flies first.
BTW for those asking about weights, I have watched all the videos and the engine install including all radiators fluids, redrive etc was 750lbs.- that will also need some work akin to what lycoming did with the the repruposed diesljet engine (which started life as a 2 litre alfa romeo diesel – they bought the concept put it on a diet and made it into the del-120 engine for drones
https://dieseljet.com/
https://www.lycoming.com/engines/del-120

I wonder what his next step will be. Feels like he’s had enough of test pilots and he’d like to become one himself.

EBST, Belgium

Probably, and given that he is not of the listening kind, not sure how good an idea that is.

Biggin Hill

an older comment, reposted today on homebuildairplanes…

Yesterday at 5:11 PM
#5,540
Here is the comment from Pipistrel test pilot Sašo Knez:

Hi! I know that it will probably not have any effect, but I have to say this for my own piece of mind.

When I was a younger and inexperienced test pilot at a dive to VD test I lost one aileron to flutter and the control rod to the other broke. I was very lucky to walk away. That was a structurally strong and sound aircraft.

You have an aircraft that is terribly weak in the most of the bonded and fitted assemblies. Having tested just composite aircraft I had never seen assemblies and load-carrying structures as you have in your aircraft. Add to that a lot of freeplay both in structures and in controls and you also have a definite flutter problem.

I urge you not fly it. It will kill you in an heartbeat. In the first seconds of the flight you will struggle with unconventional control responses, which will set up a PIO and those large deflections will develop into a flutter even at low airspeeds. With such a heavy engine behind you and the kinetic energy of a 70 kt+ impact the chances for survival are surely zero.

On the other hand I fully understand your investment and the financial stakes on this project. The only way forward is to find a way that you can personally make an exit from this project. The other two courses of actions are either murder/suicide or basically restarting the design from zero.

*Sašo Knez, Slovenia, EU Full member of Society of Experimental Test Pilots (SETP)

The other two courses of actions are either murder/suicide or basically restarting the design from zero.

Good old eastern-european diplomacy

EBST, Belgium

@hammer – thank you very much for posting this!

@airways – I was thinking exactly the same thing… If only he knew that exactly this comment would close the ears of (nearly) any American entrepreneur out there

Last Edited by AF at 23 Aug 19:08

Well, he flew it…

EBST, Belgium

This whole thing seems more like a slightly bizarre youtube/facebook “event” exclusively – gradually unfolding in odd directions, fueled by “clicks” alone

The elephant is the circulation
ENVA ENOP ENMO, Norway



EDQH, Germany
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