T42

T42 may refer to:

Vehicles

 * Beechcraft T-42 Cochise, an American trainer aircraft
 * T42 medium tank, a 1950s American tank design
 * T-42 super-heavy tank, a Soviet tank project from the inter-war period
 * SJ T42, a Swedish diesel-electric locomotive
 * Slingsby T.42 Eagle, a British glider
 * Cooper T 42 a series of racing cars participating in the Eläintarhan ajot competitions
 * Mecklenburg T 42, a former class name for a Class 99 steam locomotive

Other uses

 * T42 (classification), a disability sport classification for above knee amputees
 * IBM ThinkPad T42, a laptop model
 * Ruth Airport, in Trinity County, California, United States