The CASA C101 " Aviojet " is the training airplane of the Spanish Air Force. This airplane represents the second generation of basic jet trainers. The initial project of the C-101 goes back to the summer of 1974. Fulfilling the terms of the program of development in remarkably short time, the first prototype was presented the public on 27 May 1977. In less than a year, four prototypes were already in the air. During 1978 the newly created Ministry of Defense requested a total of sixty units of the C-101, a number later increased to eighty. The first C-101 of series production flew on 08 October 1979 , and the four first units were given officially to the Aviation school of San Javier on 17 January 1980.

The Aviojet is in service in Spain, Chile, Honduras and Jordan. About 145 were delivered. The Spanish Air Force uses the version EB, though the company has developed other versions. Version CC is an airplane of tactical support, able to use different types from pumps and rockets, and the last version the DD, is also of tactical support with a new system of mission and avionics.

The Aviojet is the exhibitor of the Spanish Air Force, being the airplane used in its exhibitions by the Team Aquila "Eagle" squadron that flies acrobatics at air shows.