A question for Corsair and Skyraider experts

[JohnB]

It's well known that Boeing held the patent for the backward folding main gear where the wheel/tire rotates 90 degrees to lay flat within the wing. It was a early Boeing design and licensed to Curtiss where it was used in the P-40 series.

The Corsair and Skyraider feature similar gear legs. Did they also license the Boeing design?

[Invader26]

Don't forget the Vultee Vengeance and CW-20/P-36 too.

Last edited by Invader26 on Tue Apr 29, 2014 7:52 am, edited 1 time in total.

[famvburg]

Seems to me the early Aero Commanders did that as well.

[davidwomacks]

It's well known that Boeing held the patent for the backward folding main gear where the wheel/tire rotates 90 degrees to lay flat within the wing. It was a early Boeing design and licensed to Curtiss where it was used in the P-40 series.

The Corsair and Skyraider feature similar gear legs. Did they also license the Boeing design?

If they went about it in a different way IE didn't copy Boeing plans then I don't see why they would have to license it,That particular design would belong to Vought

[JohnB]

If they went about it in a different way IE didn't copy Boeing plans then I don't see why they would have to license it,That particular design would belong to Vought

I didn't say they should have to license it...just asked whether they did...or if they have their own (but conceptually similar) design?

[John Dupre]

Don't forget the Vultee Vengeance and CW-20/P-35 too.

The Seversky P-35 main gear just rotated straight back with the wheels then partially covered in fairings. The wheels did not rotate to lay flat inside the wings.

[Invader26]

Typo, mean't P-36/Mohawk...posting corrected eagle eye...tks

[shrike]

Depending on how the patent was written, they would have paid a royalty to Boeing. Cheaper to do that than to fight it in the courts.

Even if there is a war on, governments and 'the market' have a habit of enforcing patent law. ex: nearly every artillery shell fired by the British in WWI had a Krupp patent fuse. After the war was over, a substantial cheque went it's way into Germany. The ACW had the same thing, with the CSA upholding northern patents until things broke down completely in 1865 - led to some very interesting small arms with everyone trying to innovate and avoid infringement.

[51fixer]

P-40 rotation was accomplished using gears. One bolted to the wing and the other on the upper end of the gear strut. Pivoting the gear aft caused the rotation. The gear leg sat against the wing and only the wheel and brake was in the wing. The P-36 was essentially the same design.

The Corsair had a mechanical link on the top of the upper strut instead of gears to create the rotation and was housed internally without any portion of the gear outside the wing. It also had to shrink down in length to fit in the wing and there was a cable that pulled against the gear to make to it shorten as it retracted along with a couple of pressure chambers internally in the strut.

The AD prototype used Corsair gear legs IIRC for testing or first flights. It's gear system is very similar to the corsair but sat partially outside the wing aka P-40. It was built a bit heavier duty than the Corsair's for the increased weight of the AD.

A-4 MLG rotated as well but retracted forward.

Even the nose gear of the A-26 rotated on retraction.

As for patenets many are searchable with google, ect. Might be interesting to see who originally had the patent.