Mystery Aircraft Quiz #6

[Pilawt]

This mystery airplane was the first to be FAA certified with a particular design feature, one that is now becoming fairly common. The first prototype flew in 1969. Six were built, powered by a Continental IO-520. One was sold to the USAF.

What was the name of the airplane, and what was its revolutionary design feature?

-- Pilawt

Grumman G44-A?

Nope. This was not a large aircraft manufacturer, though this airplane was developed in association with a major non-aviation industrial company.

-- Pilawt

 

[SCCutler]

I was waiting for this one to come up.

The Windecker eagle, product of a west Texas Dentist (Dr. Leo Windecker) and his research into plastic airframe (hence, first composite airframe).

I thought- think- it is a beautiful form, but (like so many aviation business efforts) it failed.

Wish...

Edit- Plastic construction developed with DuPont, IIRC.

 

[Dean]

Windecker A/C7 Eagle.

 

[Pilawt]

I was waiting for this one to come up.

Am I that transparent?

The Windecker eagle, product of a west Texas Dentist (Dr. Leo Windecker) and his research into plastic airframe (hence, first composite airframe).

Right on target.

Edit- Plastic construction developed with DuPont, IIRC.

It was Dow Chemical.

In one sense the lightweight composite construction was too good. The wings were so light that the relatively heavy engine and tail acted like a bolo in early spin tests, making an aft CG spin unrecoverable. The test pilot survived only because he was able to get his foot out of his shoe which was caught in the door. As a result the certified airplane had a larger ventral fin and the record for being the most spin-tested airplane in history.

Good job.

-- Pilawt

 

[Henning]

I was waiting for this one to come up.

The Windecker eagle, product of a west Texas Dentist (Dr. Leo Windecker) and his research into plastic airframe (hence, first composite airframe).

I thought- think- it is a beautiful form, but (like so many aviation business efforts) it failed.

Wish...

Edit- Plastic construction developed with DuPont, IIRC.

Well, I wouldn't think to call it "composite" in those days. If they were going pith plastics at that time, I would imagine it being GRP, (which if I remember my polymer history correctly would have been Dow with their Polyester and Vinylester compounds). In those days "Composite" construction would have designated metal and wood.... Now a days "composite" typically designates a mix of carbon fiber, kevlar, and S or E glass used in varying proportions rigidized by epoxy, poly or vinyl-ester compounds. On that note, I'm gonna try to talk my buddies mom into letting me make a set of molds off her C-18.

 

[Pilawt]

Well, I wouldn't think to call it "composite" in those days. If they were going pith plastics at that time, I would imagine it being GRP, (which if I remember my polymer history correctly would have been Dow with their Polyester and Vinylester compounds).

According to the National Air & Space Museum website, it was

"a patented flexible, non-woven glass fiber material called 'Fibaloy.' The material had excellent properties that permitted it to be molded into complex shapes and it was easily glued and machined, making it ideal for many aircraft manufacturing and other applications."
​

The USAF designated its Eagle as YE-5A, and used it to test its "stealth" characteristics.

-- Pilawt

 

[Henning]

According to the National Air & Space Museum website, it was

"a patented flexible, non-woven glass fiber material called 'Fibaloy.' The material had excellent properties that permitted it to be molded into complex shapes and it was easily glued and machined, making it ideal for many aircraft manufacturing and other applications."

​

The USAF designated its Eagle as YE-5A, and used it to test its "stealth" characteristics.

-- Pilawt

Yeah, Fibaloy was a patent name for a glass mat and was typically employed with polyester back then, although vinylester was already popping its nose onto the scene with its reduced hygroscopic properties (this problem has still not been totally eliminated). There would though have to be some woven/roven involved in some structural areas for rigidity. Matt forms beautifully, especially in compound curves, it lacks some structural properies though, which is why they make both. You can even buy rolls that already combine mat and weave in layers. I've got a roll of Carbon/Kevlar biaxial just waiting for a project to use it on.

 

[SCCutler]

OK, Dow, and I was going to post the trade name "Fibraloy," in which instance I would not have been too far off, but I was avoiding posting instant research, which in my mind misses the fun of this most excellent exercise...


...for which you have my sincere thanks.

Hey: Idea! make flash cards, come to Gaston's on June, fun game for all.