Pitcairn XO-61
      
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]
See also
- Aircraft of comparable role, configuration and era
- Related lists
References
Citations
- ↑  Gregg, E. Stuart, "Above & Beyond: Jump Ship". Air & Space Smithsonian, March 2001
- ↑  Harris, Franklin D. An Overview of Autogyros and The McDonnell XV-1 Convertiplane, NASA/CR—2003–212799. NASA Ames Research Center, October 2003
- ↑  Cully, George & Andreas Parsch: MX-1 to MX-499 Listing, designation-systems.net
- ↑  Wings of Freedom Winter 2007/2008, Volume 22 Number 4, Delaware Valley Historical Aircraft Association.
 
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.
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