Ka-1 autogyro

[tom!]

Hi.

The japanese Ka-1 autogyros were used for recon duties in anti-submarine warfare e.g. from the IJA landing craft mothership/aircraft carrier Akitsu Maru:









Yours

tom!

[Adrian Roberts]

They look like copies or licence-built versions of the American Kellett types - do you know if this was the case?

[Antipodean Andy]

Excellent post of an obscure subject, Tom! Just what we like!

[tom!]

Hi.

In 1939 the IJA bought a Kellet KD-1A autogyro and tested it for the use as artillery spotter. During the early stages of the tests it crashed during low-speed flight.

The remains were sent to Kayaba Seisakusho K. K. (Kayaba Industruial Co. Ltd) at Sendai which were already developing an own autogyro. On May 26th,1941 the Ka-1 made its maiden flight. It was designed as two-seat obervation autogyro powered by an Argus As 10c 8-cylinder air-cooled engine with 240 HP.

Until 1943 only some were produced and used with independent heavy artillery regiments. It was quite manouverable and maintainance in the field was no problem.

In 1943 the shipping losses caused by allied submarines became a certain threat to japanese military shipments. So IJA decided to refit several merchant ships and army ships as escort carriers.
As the landing craft mothership Akitsu Maru was originally built with a flight deck and hangar only few modifications had to be made and so the ship became combat-ready as escort carrier in late 1943.



The short flying deck didn´t allow the use of avaliable army airforce planes and the navy refused to give planes (which also would had problems landing on the deck). So the KA-1 with the ability to take-off fully loaded after 30 m became first choice. For anti-submarine warfare the KA-1 was modified so that instead of the spotter in the back two 60 kg depth charges could be loaded. Other modified KA-1 were used for coastal patrols.

In 1944 trials with additional powder rockets on the rotor tips and a Jacobs L-4MA-7 240 HP 7-cylinder air cooled engine were made to increase the possible take-off weight for additional or larger depth charges were made but without success.

Some 240 KA-1 were built

Yours

tom!

[Kyt]

Are there any reports of operational successes, whether in spotting or damaging US subs?

US losses to enemy actiion were minimal, basically because of the poor state of Japanese AS services and equipment. They even failed to institute a dcent convoy system until it was too late.

[tom!]

Hi.

No further infos, sorry.


Yours

tom!

[Adrian Roberts]

The Japanese must have used more autogyros than any other nation in WW2, and probably the only nation to use them in combat, (or reconnaissance at least).

AFAIK the RAF only used theirs for radar calibration and similar duties.

The Germans used Flettner Fl282 helicopters (not autogiros) for shipboard reconnaisance, but in much smaller numbers than this.

[Antipodean Andy]

Interesting ship.

[Nostalgair]

Hi All,

Here's a US KD-1A Autogyro.

Web AGyro.jpg

Cheers

Owen

[tom!]

Hi.

I found this nice japanese video on the KA-1. It also includes a carrier take-off and landing (last part of the video) on Akitsu Maru (at least the speaker mentioned the ship´s name...)

YouTube

Yours

tom!