09/30/2013. Remarks by Johan Visschedijk: "Developed to meet a specific Marine Corps requirement, the Cessna Model 321 was similar to the OE-1/L-19 series, but used Model 180 wings, a new fuselage, armored panels, two wing hardpoints, and a supercharged 260 hp Continental O-470-2 engine. The prototype, registered N41767 (c/n 611), first flew in September 1954.
A batch of 25 (BuNo. 140078 to 140102) went to the USMC as OE-2s in 1955 and two in 1956 (BuNo. 148250 to 148251), but the higher cost of this model prevented its adoption on a wider scale. Factory fresh BuNo. 140081 was assigned to Marine Observation Squadron One (VMO-1) as indicated by the tail code 'LR'. The designation changed to O-1C in 1962."