A Gap to be Bridged
In the mid 1960s, with the conflict in Vietnam raging, the U.S. Air Force had an acute need to replace The Cessna O-1 Bird Dog aircraft which were being used to perform the critical but highly dangerous Forward Air Control (FAC) mission.
The FAC mission involved low flying into enemy territory to perform light reconnaissance and target marking for incoming strike aircraft. The slow, lightly built, single engine O-1 was proving extremely vulnerable and being lost in unacceptably high numbers.
The North American OV-10 Bronco, an aircraft designed with the FAC mission in mind, had been selected by the U.S. Air Force as a replacement for the O-1. However, the Bronco was still under development when the need to replace the O-1 became critical. An interim solution was required.
Not Perfect, but Much Better
In 1965, the U.S. Air Force looked to another Cessna product to replace the O-1 and carry out FAC duties until the OV-10 was ready for service; the Cessna model 337 Skymaster, like the O-1, was a civil aviation design never envisioned to see military service. After some experimenting and testing, an order was placed for Cessna to produce a militarized variant of the 337 which would become known as the O-2.
The O-2, being a civil design first and foremost, was an exercise in improvisation when it came to military service. However, through it’s higher speed, more robust construction, ease of operation and maintenance combined with the more survivable nature of a twin engine design, the O-2 quickly gained popularity with those who flew and maintained it.
A particular stroke of luck was in how Cessna had gone about making the 337 a twin engine design. While most of their contemporaries were designing twin engine aircraft with the engines placed on wings mounted low on the fuselage, Cessna placed both engines in the fuselage in a distinctive “push-pull” arrangement which allowed the wing to be mounted above the aircraft’s cabin. This designed provided excellent all around visibility for the observer in the aircraft, a quality essential to any aircraft carrying out the sort of missions that the O-2 was.
Between 1967 and 1970, Cessna produced roughly 530 O-2 Skymasters in two versions:
The O-2A was the armed version used in FAC and light reconnaissance work.
The O-2B was an unarmed variant equipped with loudspeakers for psychological warfare.
The O-2 did remain active in Vietnam even after the OV-10 Bronco entered the conflict. Several O-2s were given to the South Vietnamese Air Force to operate.
The O-2 carried on in U.S. military service well into the 1980s and served the air forces of around a dozen other countries, many of them developing nations, over the years.
Many former U.S. military Skymasters found post military use in forest service work, such as controlling fire fighting aircraft.
The O-2 Today
Several former military O-2s have found a second life as preserved flyable examples in the “Warbird” class of aircraft. The mix of relatively low operating cost, available spare parts and ease of operation and maintenance has made them popular in this category.
It was a bit of a challenge to find good reliable information online about the O-2 and model 337 in general, but these two sites have some decent information about the history and development of both: