The 1926 Thomas-Morse O-6 is a metal-frame versions of Douglas O-2 built by Thomas-Morse under government contract. One went to McCook Field for testing as P-439 (25-435), and with a 435hp Liberty V-1650-1 was re-designated as O-6 (25-436).
Three production O-6 were built (25-437/439) with Liberty 12 engines.
The XO-6B of 1925 was a re-design of the O-6 with a 450hp P&W R-1340, revised wing covering and bracing, corrugated metal fuselage skin. One (25-440) was built as the prototype for O-19, McCook tested it as P-503.
All Aero 