A very cool experimental aircraft

[flyvulcan]

This aircraft is for sale in the US.

 

I was fortunate enough to view it during construction and watch it take shape.  I never saw it finished until it was listed for sale recently.

 

Its nickname by its designer/builder (Bill Husa of Orion Technologies) was Gumbo.  It was to be a custom unlimited Reno racer.  Anyway, I thought some may find it interesting.  If you have US$350k, you can buy it outright.  It has not yet flown and the owner is already selling the engines off so is parting it out.  Very sad....

 

 

 

 

 

 

[pmccarthy]

Why?

 

 

[flyvulcan]

Why?

We haven’t been able to find out.  Run out of money to be able to race it at Reno, afraid to fly it, we don’t know.

 

Having watched it grow from concept to reality, I’d be disappointed if it didn’t get to fly.  I was working on a project with Bill Husa who designed and built it.  Bill was designing an aircraft for me.  I spoke with him on a phone call one day to discuss our project and he told me that he hadn’t been well the last few weeks, but that he would be sorted within the next couple of weeks.  I read on another forum a week later that he had died.  He had cancer and not told anyone.  He was probably only around 50 years old.  Bill was a terrific guy and a real asset for the homebuilt community with his unselfish sharing of information and advice.  He is sorely missed.

 

 

[Marty_d]

You'd need stones like coconuts to test fly that plane.  Hell of a lot of engine and not much wing, I reckon stall speed would be high.

 

 

[spacesailor]

And the Driver is far,far back of "CG"

 

Or is it an illusion.

 

spacesailor

 

'

 

 

[Jaba-who]

And the Driver is far,far back of "CG"

Or is it an illusion.

 

spacesailor

 

'

I’d guess he’s that far back to help balance the weight of the two engines so far forward. 

 

 

[pylon500]

Yeah, the old adage, 'If it looks right, it should fly right...'

 

This thing looks like a flying death trap!

 

Two big engines and barely enough of anything else to aim them in the right direction.

 

I didn't follow the build, so I can assume those that did, possibly saw a lot of high tech effort go into the construction and therefore think the same effort went into the aerodynamic design...?

 

I'm not saying this is incapable of flight, far from it, but as Marty said, I think the cockpit needs to be bigger fit the required 'stones' need to fly this.

 

Basic upfront design problems at first sight....

 

Totally useless rudder, will barely keep plane straight with both engines perfectly matched.

 

Will also have very limited effectiveness where needed (at low speed) because of the sweep angle, it'll basically be an elevator by then.

 

Short span, short couple, and both engines turn the same way!?

 

And why are they spaced so far out along the wing?

 

This was supposed to be for racing, racing engines fail, single engine opps in this thing will be;

 

Critical engine and fatal engine.

 

Sorry if sounds down on someone who appears to have been well involved, but this just looks like one of those, 'Nope!' type aircraft.

 

You want two engine, one pilot, go fast?, look at the Pond Racer, It ticked all the boxes, then read what Dick Rutan said about flying it.

 

Admittedly, he said it was better than the Voyager.

 

Gee, not here for ages, then come here and rants!

 

Sorry folks.

 

 

[spacesailor]

In this day & age. Why do we have to have All engines rotating the same way from the same maker

 

Surly making a crankshaft & camshaft isn't that hard on the new CN machinery.

 

Iv'e watched a billet of alloy Turn into a V8 block in hours, Not days.

 

The contortions of the "Lathe" (if it's called that now) making a Cam, makes good entertainment, same with a crank having Journal work done.

 

But the crank is inside a "safety housing, so no viewing.

 

Always thought that having the prop-wash thrown "under the centre section",  by both engines running contra rotation make better aerodynamics.

 

spacesailor

 

 

[Deskpilot]

It'd be easier to just make a special reverse drive gearbox, Wouldn't it?

 

 

[facthunter]

 No to the reverse gearbox is it needs an extra idler and is weaker  and big changes to the engine case. I think you will find the normal makers make contra rotation options and the props, on suitable engines.

 

  With high speed aircraft you have a difficulty keeping the nose from rising in S & L and so it's probably on the limits of nose heavy to start with and has a large full flying horizontal stab. for the same reason.. The engines might be more efficient a bit further out on the wing with cleaner air and the fuselage not creating interference. Out there not being contra rotating has less effect. It just gives a higher VMc (a) when one particular engines out. I doubt the designer is too worried about that nicety and the Tail? Why so much sweep back? if it's not supersonic. Suspect it's a "wow", design for looks, factor.  Nev

 

 

[spacesailor]

F C

 

That it certainly is "WOW".

 

spacesailor

 

 

[flyvulcan]

The designer, Bill Husa was a very experienced design engineer.  He had many successful designs under his belt and both aerodynamics and structures were his areas of expertise.  Some extremely novel and innovative design features are incorporated into the construction of this aircraft.  For example, it does not have a standard spar structure.  Instead of a main and rear spar, I believe there is a series of corrugation like structures within the wing to replace the typical spar/rib structure.

 

Bill was extremely aware of Vmca issues (minimum control airspeed on a single engine for those not familiar with the term) and  indeed, we discussed this when I viewed the aircraft.  He had designed the aircraft such that this should not be an issue.  The vertical stabiliser is actually quite large and has a long moment.

 

I sincerely hope that this aircraft is flown successfully, and that it can continue to do so as a testament to Bill’s contribution to the recreational aviation fraternity.

 

 

[pmccarthy]

Looking at the photos I think the engines are about as far inboard as they could go. The front-on photo is misleading because of the perspective.

 

 

[SSCBD]

Look like a mini piper aerostar at the front.

 

 

[skippydiesel]

 No to the reverse gearbox is it needs an extra idler and is weaker  and big changes to the engine case. I think you will find the normal makers make contra rotation options and the props, on suitable engines.............................................................................................................

   Nev

 Please explain  (more detail) Seems to me that Rotax (& in the past others) have shown that geared engines are a viable design option and if you go this rout then a left & right rotation gear box would be the way to go.

 

It must be very expensive to manufacture the few concentrating engines demanded by the industry, I suspect a gear box much less so..

 

 

[facthunter]

 Gears are always a problem engineering wise the best are sun and planetary or use multiple layshafts. Too many torsional harmonics. in most drives even from turbines spline drives will wear rapidly at certain torque figures. Piston engines drives are full of shudders. That's why the Rotax goes to a lot of trouble to have a shock absorbing slipping clutch (damper) and  cam thing in the dear drive. Also fairly heavy and costly and needs inspection and. servicing. Its easy to reverse an engine's rotational direction especially if you do lots of them. and up to about 350 hp CAN be direct drive. BIG Piston  engines need a reduction gear usually about 2:1 to keep prop tip speeds down below supersonic. Turbines especially small ones need from 100,ooo RPM to about 3,000 so about 33:1. again sun ad planetary is the go there.. IF you flame out you have a great air brake unless you feather the prop quickly with most turbines.  Nev