NTSB report Jet powered Quickie


Sam Hoskins
 

Here is the beginning of the story.

https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20160513X30806&key=1
Sam

Sent via wireless Gizmo.


David J. Gall
 

All respect and kudos to Mr. Seguin, however, trying to expand the envelope to crosswind landings (15 to 18 kts direct x-wind) on flight number three with 0.8 hours on the airplane is ... well ... dumb. Even if the "airframe" (Q1) is a "known quantity," the new power plants made it a whole new airplane. The downwind (lee side) engine flamed out? Look at the configuration and tell us you couldn't have foreseen that.

Then again, I seem to recall more than one report of a Q1 being unable to recover from a low altitude roll/yaw resulting in ground contact in an undesirable aircraft state ("crash"). Eh, Jimmeh?

ALL envelope expansion, including yaw conditions, should be extensively investigated AT ALTITUDE before being employed as an operational requirement (i.e. crosswind landing *requires* some amount of yaw/slip). Translation: try some slips at altitude before deliberately *needing* them for a crosswind landing. "Discover" that the lee side engine will flame out in a slip while you have sufficient altitude to recover, not on deliberate crosswind landing attempt number one. At least know the engine-out characteristics before *planning* to do touch-and-goes! Sheesh.

Remember, this is Experimental Aviation and it is incumbent on each of us, however many Quickies have flown before, to test fly OUR new Quickie/Q2/Q200/Q-baru/Q-whatever as though it was the first one ever built. When you bought the kit you signed up to be a test pilot - act like one or hire one. (Try SETP.org)

I hope we all learned from this....


Tommy Castleman
 

Wow.... 

This is interesting to me because last semester I had a discussion with a fellow NASA intern about putting jet engines on a quickie. When we were having that discussion, I did not know about this airplane. I thought it was a bad idea, and that it would be easier/better to redesign the aircraft. I even laughed at him, because he kept going on about how "easy" it is to put R/C jet engines on a quickie (he didn't know much about the airplane).

I was very surprised to see that someone had actually done it. When we had that discussion, the plane had not yet flown. Although, I would still consider the addition of the extra fuel tanks a redesign.

I have to give a lot of credit to Elliot Seguin, though. He had an idea, and did more than talk about how cool it would be. He actually built and flew it. It's unfortunate that it did not go past a third flight, but thankfully he survived. I'm sure he will sit down and do a thorough "lessons learned," before attempting anything new. I would be interested to see what his next idea is!

I must say.... Sometimes I can be a tiny bit superstitious. Maybe perhaps he "cursed" the project by calling the airplane a "twerp." No offense.

twerp



nounSlang.
1.
an insignificant or despicable fellow:
Her father thinks her boyfriend is just a twerp.



Bob Wilson
 

First kudos for the excellent airmanship. The pilot had the good sense to not apply full power and lose control of the plane. He moderated the power so the remaining engine would not force it into something worse. However, I have a couple of questions because it relates to my project.

My plan is to replace the heavy VW engine (long since gone) with a modern, light-weight, liquid cooled, two stroke. This means the engine has to move forward to maintain the CG and that increases the area ahead of the CG. So my plan is to fit a dorsal to the rudder to maintain rudder control. But when I look at the photo of N68TQ, the nose has been substantially lengthened. Was more rudder area added?

Engineering is a delicate balance of tradeoffs so I'm curious why the engines were mounted mid-fuselage instead of possibly pylons at the front (aka., Cri Cri ?)

Thanks,
Bob Wilson


Andrew Power
 

The motors started on the nose and then moved mid-fuselage.  There is a video out there (Vhttps://www.youtube.com/watch?v=x_keYAFcsXU) with the owner during taxi trials.  Search Elliot Seguin, Wasabi Air Racing Twerp.  He explains the reasoning.

Andrew Power


ryan goodman
 

It's interesting to read. Lots of questions in my mind though. It seems like some things just were not thought out.


On Sun, Feb 26, 2017 at 7:29 AM, andrewpower.pbs@... [Q-LIST]
wrote:
 

The motors started on the nose and then moved mid-fuselage.  There is a video out there (Vhttps://www.youtube.com/watch?v=x_keYAFcsXU) with the owner during taxi trials.  Search Elliot Seguin, Wasabi Air Racing Twerp.  He explains the reasoning.


Andrew Power


Allan Farr
 

I have heard that two strokes don't really suit fast slippery aircraft as they have to be continually under load so as not to seize

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Robert Bounds
 

Uuuhhh, kinda.  They tend to dry out in a long, fast, windmilling descent because the engine is lubricated internally by the oil mixed into the fuel and if they aren’t getting much fuel , they aren’t getting much oil.  This can be dealt with by slowing the plane before the descent and giving it a shot of throttle every few seconds.  The bigger problem that I found is the steep torque curve that they have.  A prop with enough pitch to get a decent cruise is too much for the motor to spin up at slow speeds and low rpm.  The engine has to be somewhat detuned by using a single carb and lengthening the exhaust in order to get a little more torque on the bottom end.  You lose some horsepower on the top doing this but that was the only way I could get mine to work well.  It finally got to where it worked fine.
Bounds
250 hours in a Rotax 503 Q1

From: Allan afarr@... [Q-LIST]
Sent: Monday, February 27, 2017 5:23 PM
To: Q-LIST@...
Subject: [Q-LIST] Re: NTSB report Jet powered Quickie
 
 

I have heard that two strokes don't really suit fast slippery aircraft as they have to be continually under load so as not to seize

Sent from my Xperia™ smartphone