7. Aircraft used for aerial refueling: KC-135 Stratotanker

Joined the Service in 1957
Producing company: Boeing
Price: $39.6 million
KC-135 Stratotanker, which made its debut in 1957, has been the mainstay of the U.S. The aerial refueling activities of the Air Force. This reliable workhorse, made by Boeing, has been essential in increasing the endurance and range of American military aircraft.

Aerial refueling aircraft KC-135 Stratotanker ©TSgt Angelique Perez / Wikipedia.org
The KC-135’s recognizable flying boom has made it possible to carry out innumerable long-haul missions, from Cold War patrols to contemporary operations all over the world. It has been modified for use in transport and special mission duties in addition to refueling. The Stratotanker is still a vital tool in the skies decades later, which is a testament to its versatility and ingenuity.