The use of commercial technologies for upgrades to Pratt & Whitney's [RTX] F117 engine for the U.S. Air Force C-17 airlifter by Boeing [BA] obviates the need for a re-engining of the 222 C-17s in the service's fleet, according to the U.S. Air Force. Boeing delivered the aircraft between 1993 and 2013. In an email response to questions on Thursday, Air Force Life Cycle Management Center (AFLCMC) at Wright-Patterson AFB, Ohio, said that the center "has affirmed the continued viability…