Pitcairn XO-61 explained

The Pitcairn XO-61 was an American autogyro designed by Pitcairn Aircraft. One of the last autogyros produced, in competition with the Kellett YO-60 and the Sikorsky R-4, it fell victim to cooling problems with its rear-mounted engine and the coming of the helicopter with its ability to hover.^{[1] [2]}

Also known by the company model number PA-44 and the contract designation MX-157,^[3] the contract for the XO-61 was taken over by G&A Aircraft upon G&A's acquisition of Pitcairn Aircraft.^[4]

References

Bibliography

• Cully, George & Andreas Parsch: MX-1 to MX-499
• Gregg, E. Stuart, "Above & Beyond: Jump Ship". Air & Space Smithsonian, March 2001 Listing, designation-systems.net
• Harris, Franklin D. An Overview of Autogyros and The McDonnell XV-1 Convertiplane, NASA/CR—2003–212799. NASA Ames Research Center, October 2003
• Wings of Freedom Winter 2007/2008, Volume 22 Number 4, Delaware Valley Historical Aircraft Association.

Notes and References

1. Gregg, E. Stuart, "Above & Beyond: Jump Ship" . Air & Space Smithsonian, March 2001
2. Harris, Franklin D. An Overview of Autogyros and The McDonnell XV-1 Convertiplane, NASA/CR—2003–212799. NASA Ames Research Center, October 2003
3. Cully, George & Andreas Parsch: MX-1 to MX-499 Listing, designation-systems.net
4. http://dvhaa.org/newsletters/dvhaa-newsletter-07-08-winter.pdf Wings of Freedom Winter 2007/2008