Boeing KC-135R

177 aircraft

The KC-135R Stratotanker, the United States Air Force's primary aerial refueling aircraft for over six decades, fundamentally transformed strategic bomber operations and global air power projection. First flown in 1956, it is a swept-wing four-engine jet aircraft powered by Pratt & Whitney TF33 turbofan engines, capable of transferring fuel through its telescoping boom system. With a service life spanning from 1957 to at least 2050, the KC-135R represents one of only nine military aircraft to achieve over 60 years of continuous service with its original operator. Manufactured by Boeing at their Renton, Washington facility.