Plans were made in 1941 to build 1489 A-20Bs modified for
photo-reconnaissance and observation duties under the designation
O-53, but this project was cancelled in June of 1942.
Serials of O-53:
41-3670/5158 Douglas O-53 - heavy observation version of A-20.
contract cancelled.
Sources:
-
American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday,
1982.
-
McDonnell Douglas Aircraft Since 1920, Vol 1, Rene J. Francillon,
Naval Institute Press, 1988
-
United States Military Aircraft Since 1909, Gordon Swanborough and
Peter M. Bowers, Smithsonian, 1989.
-
A-20 Havoc in Action, Aircraft Number 144, Squadron/Signal Publications,
Jim Mesko, 1994.
-
War Planes of the Second World War, Fighters, William Green, 1964.
-
Boston, Mitchell and Liberator In Australian Service, Stewart Wilson,
Aerospace Publications, 1992.
-
Jane's Fighting Aircraft of World War II, Military Press, 1989.