These wild prototypes were killed before they got the chance to really spread their wings, as it were.

10.) Vought XF5U


The “Flying Flapjack” was a brilliant idea, but it came at the exact wrong time. Reader DennyCraneDennyCraneDennyCrane can explain:

“During World War II, some bright cookie figured out that, if you put the propellers at the very edge of the wing tips, and had them rotate top->outside->bottom->inside, it would cancel out the wingtip vortex.

And it flew! It flew WELL!

Now, cancelling the wingtip vortices may not sound like a big deal, but look at the plane: It’s a flying saucer. It allowed for such a shortened wingspan, and the plane could basically take off and land vertically! It could land on lousy air-fields at low speeds,

So they make the full size version, and eventually cancel the plane in 1947 because jet engines are the new hotness, who wants a prop driven fighter?

Of course, if you think about its potential for close air support, with how rugged, how long it could loiter, how slow it could go... it suddenly makes sense, right? But I guess the Air Force brass just never thought about that. The Air Force is known for never prioritizing fast-movers over close air support missions...”

Suggested By: DennyCraneDennyCraneDennyCrane, Photo Credit: SDASM Archives

9.) Boeing X-32


The X-32 was Boeing’s entry into the Joint Strike Fighter contest, which lost out to the Lockheed Martin X-35. The X-35 evolved into the F-35, yes, that F-35.

It’s fun to imagine how different things could have been if the X-32 had won.

Suggested By: mikewballou, Photo Credit: USAF

8.) Fairey Rotodyne


A compound gyroplane, like the Fairey Rotodyne, combines the best of a helicopter and a helicopter plane. You could take off vertically with the rotor, and switch to the props for cruising.

There was so many possibilities with the Rotodyne but politics, a lack of commercial orders, and noise complaints killed it.


Suggested By: 2 Wheels awesome!, Photo Credit: J Thinesen, SFF photo archive

7.) Goodyear Inflatoplane


This aircraft does exactly what its name suggests. The idea was for it to be a rescue plane to be inflated behind enemy lines, and it worked! Yes, Goodyear actually got this thing to inflate and fly.

The killjoys at the U.S. Army cancelled the project because they didn’t want a plane that would be so easy to shoot down.


Suggested By: GarageWoolery, Photo Credit: Public Domain via Wikimedia Commons

6.) Boeing 2707


The 2707 was America’s first attempt at supersonic passenger transport. It was killed for the typical reasons supersonic transport has proven to be unviable: cost, commercial potential, and noise concerns.

Still though, supersonic transport truly captures the imagination. It’s impossible not think of what life would be like if it existed on a wide scale.


Suggested By: TheHondaBro, keeper of C&H, Photo Credit: via Jalopnik

5.) Convair NB-36H


What’s more Cold War than a bomber powered by a nuclear reactor? Not much, honestly.

Theoretically it could fly for weeks on end, but the project was killed due to the rise of the ICBM, and you know, cost and safety.


Suggested By: macanamera, Photo Credit: USAF

4.) Avro Arrow


The Avro Arrow was the plane that should have made the Canadian air industry a force to be reckoned with. It could travel at three times the speed of sound and at an altitude of 60,000 feet.

It’s cancellation remains a bit of a mystery to this day. The Canadian government officially said it was too expensive, and the fact that Sputnik was launched on the same day the first Arrow was produced didn’t help either.


Suggested By: sheogorath, Photo Credit: Dennis Jarvis

3.) RAH-66 Comanche


Like many of the others on this list, the Comanche was killed due to escalating costs ($7 Billion dollars), which is a bit of a shame because it could have been one of the most incredible helicopters ever produced.

Suggested By: Jeb_Hodge, Photo Credit: Public Domain

2.) NASA AD-1 Oblique Wing


How do you reduce drag? Get the plane’s wing to rotate a full 60 degrees.

That’s what the AD-1 did. Supposedly it would use half the usual amount of fuel at supersonic speeds. It was killed because it didn’t handle well when the wing was rotated more than 45 degrees.


Suggested By: Jayhawk ‘Super Sanic’ Jake, Photo Credit: via Jalopnik

1.) XB-70


The Valkyrie could have been one of the most incredible bombers ever created, and easily one of the most beautiful aircrafts ever made, but the ICBM sort of rendered it useless.

Like the legendary SR-71, its tactic for evading interceptors was just to fly much higher and much faster.


Suggested By: reverberocket is nipping the apex..and gently blowing in it’s ear., Photo Credit: NASA

Welcome back to Answers of the Day - our daily Jalopnik feature where we take the best ten responses from the previous day’s Question of the Day and shine it up to show off. It’s by you and for you, the Jalopnik readers. Enjoy!


Top Photo Credit: NASA

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