OA - Observation Amphibian Aircraft

Model	Designation	Manufacturer	Engine(s)	Crew	Other
XOA-1		Loening	1 Liberty V-1650	2	XCOA-1
OA-1		Loening	1 Liberty V-1650	2	COA-1
XOA-1A		Loening	1 Wright V-1460-1	2	XO-10
OA-1A		Loening	1 Liberty V-1650	2
OA-1B		Loening	1 Liberty V-1650	2
OA-1C		Loening	1 Liberty V-1650	2
OA-2		Loening	1 Wright V-1460	2
OA-3	Dolphin	Douglas	2 Wright R-975-3 Whirlwind		Y1C-21
OA-4	Dolphin	Douglas	2 Pratt & Whitney R-985-1 Wasp Junior		Y1C-26
OA-4A	Dolphin	Douglas	2 Pratt & Whitney R-985-5 Wasp Junior		Y1C-26A
OA-4B	Dolphin	Douglas	2 Pratt & Whitney R-985-9 Wasp Junior		C-26B
OA-4C	Dolphin	Douglas	2 Pratt & Whitney R-985-9 Wasp Junior
YOA-5		Douglas	2 Wright R-1820-45 Cyclone	5	B-11, O-44
OA-6		Consolidated	2 Wright R-1820-45 Cyclone		cancelled
OA-7		Douglas	2 Pratt & Whitney R-1340-33 Wasp		cancelled
Y1OA-8		Sikorsky	2 Pratt & Whitney R-1690 Hornet	2	JRS-1
OA-9	Goose	Grumman	2 Pratt & Whitney R-985-AN-6 Wasp Junior	2	JRF-6B, A-9
OA-10	Catalina	Consolidated	2 Pratt & Whitney R-1830 Twin Wasp		PBY-5A, A-10
OA-10A	Catalina	Consolidated	2 Pratt & Whitney R-1830-92 Twin Wasp		PBV-1A, A-10A
OA-10B	Catalina	Consolidated	2 Pratt & Whitney R-1830 Twin Wasp		PBY-6A, A-10B
OA-11		Sikorsky	2 Pratt & Whitney R-1690 Hornet	2	JRS-1
OA-12	Duck	Grumman	1 Wright R-1820-54 Cyclone	2	J2F-5, A-12
OA-12A	Duck	Grumman	1 Wright R-1820 Cyclone	2	J2F-6, A-12A
OA-12B	Duck	Grumman	1 Wright R-1820 Cyclone	2	J2F-6
OA-13	Goose	Grumman	2 Pratt & Whitney R-985-AN-1 Wasp Junior	2
OA-13A	Goose	Grumman	2 Pratt & Whitney R-985-AN-1 Wasp Junior
OA-13B	Goose	Grumman	2 Pratt & Whitney R-985-AN-6 Wasp Junior		JRF-5
OA-14	Widgeon	Grumman	2 Ranger L-440-5	2	J4F-1
YOA-15		Republic	1 Franklin O-425		cancelled