In the late 1960s, the Spanish Air Force, or Ejército del Aire, was seeking a new transport aircraft type which was to replace outdated types such as the three-engined Ju-52, which had been used since the 1930s, so specifications for the new transport and multi-purpose aircraft were issued. In order to meet the air force's needs, Spanish company CASA (Construcciones Aeronáuticas SA) proposed a twin-engined, turboprop-powered, high-wing, non-retractable undercarriage cargo aircraft with STOL capabilities. The all-metal construction airframe had the empennage rather high behind the inclined rear fuselage section with hinged tailgate ramp enabling either light military vehicles to be embarked on the board, loading of large-sized cargo or paratroopers to jump out of the plane. The project known as the CASA C-212 Aviocar was eventually accepted and a pair of prototype machines took off for the first time in 1971. The Spanish Military assessed the suitability of the C-212 while using a small pre-production batch of eight aircraft. The type received military designation the T.12. Large scale production was commenced based on huge number of orders from almost all around the world and the type was also licence-built in Indonesia. Several consequent versions were also designed and built, differing by the type of engines used, elongated front fuselage section, larger tailplanes or added winglets.The original C-212-100 was equipped with TPE331-5-251C engines, the follow-up subversions were the C-212-200 with more powerful TPE331-10-501C power units, the C-212-300 with longer nose, winglets and fitted with even more powerful TPE331-10R-513C units and different style of propellers. Since 1984, the C-212-400 has been produced, having TPE331-12JR-701C powerplants, modernised avionic systems and increased payload.
The great number of customers and the wide variety of their requirements was the story behind why so many versions have been in production so far, which differ not only by the powerplants as described above, but more visibly by having many different styles of side fuselage sections and entrance doors. The Ejército del Aire alone, besides the pre-production batch T-12B airframes which would be later converted for photo-reconnaissance missions and known as the TR-12A, saw service of several other C-212 versions, ranging from the VIP transport type C-212 AV/T.12C through to maritime patrol airframes with large radomes and /or sensors in the front fuselage and on top of the tail fin (T.12D). It is obvious that the C-212 has been in service throughout the world and over all continents and the number of all civil sector users seems to be undefinite. In North America, the C-212 was used with the military of the United States (C-41 type), in Central and South America, air forces of Mexico, Panama, Chile, Ecuador, Colombia and Argentina. The Casa is also flying still in Europa, with air forces of Sweden, Spain, Portugal, France and Malta. In Africa, the Casa can be seen from the very north down to the southernmost territories, the users were or still are for instance Chad, South Africa, Botswana, Zimbabwe and others. Down under, the Australian Army use their C-212s in training of the Red Beret Parachute Display Team, and the Australian Department of the Enviroment use their C-212s as a part of the Australian Antarctic Division over Antarctica. In Asia, the type is operated of course by Indonesia, but among other users there might be mentioned also Thailand, Vietnam or the Philippines.