That the tanker fleet is old goes without saying. The production line for KC-135s closed in 1965, and the airframes have gone through several upgrades since assembly. In one reported case, a grandfather and grandson have both piloted the same aircraft. The current R model can offload 50 percent more fuel and are 25 percent more fuel efficient than the original A model. They also cost about 25% less to operate. Past upgrades have consisted of re-paneling the lower wing surfaces, engine upgrades and avionics improvements. The aircraft are showing their age, however, and are under constant surveillance for corrosion problems. These are inevitable with the age of the aircraft. The Air Force would like to upgrade the D and E models to the R standard, and make other improvements to keep these aircraft in the air as long as possible.
The KC-10s were standard DC-10-30CF aircraft bought after the 1973 October War. These were designed to serve as dual role tanker/cargo aircraft. These aircraft are normally used when fighter or attack aircraft units deploy overseas. The KC-10s are fitted with both the standard refueling boom (used by USAF units) and a hose reel for the hose and drogue (used by the US Navy and many allies). During and after Desert Storm, these aircraft also received hose units in their wingtips.
The replacement aircraft will be a version of the Boeing 767. The USAF expects to use these as tanker/cargo aircraft, and to have both boom and hose-type refueling equipment installed. The price tag may range in the $150m to $225m range, depending on configuration, quantity and delivery schedules.
USAF Tanker Fleet- As previously reported, the USAF may soon get a new fleet of tankers to replace the aged (some say ancient) tanker fleet. The current fleet consists of 546 KC-135s and 59 KC-10 tankers. Of the KC-135s, 254 are in the active force, 70 in the Air force Reserve and 222 in the Air National Guard. About one quarter of the aircraft are the older KC-135D and E models, and these serve with the Air National Guard. The remaining fleet consists of KC-135R and T models, the R model being the standard. The 54 T models were optimized to refuel SR-71s and special aircraft used by the CIA.