High Quality Content by WIKIPEDIA articles! The Cessna T-37 Tweet (designated Model 318 by Cessna) is a small, economical twin-engine jet trainer-attack type aircraft which flew for decades as a primary trainer for the United States Air Force (USAF) and in the air forces of several other nations. The A-37 Dragonfly variant served in the light attack role during the Vietnam War and continues to serve in the air forces of several South American nations.