And KC-X Begat E-X:

The KC-X program may be even more valuable than the $40 billion tanker modernization competition would suggest. The chosen airframe could also replace USAF’s fleet of large intelligence-surveillance-reconnaissance aircraft, much as the KC-135 platform has been adapted for today’s ISR fleet. Gen. Michael Moseley, Chief of Staff, said as much in March 20 testimony before the Senate Armed Services Committee about the 2008 defense budget. The Air Force is looking for other ways to approach the requirement left unfilled by the canceled E-10 sensor airplane program, Moseley said in response to a question from Sen. Bill Nelson (D-Fla.). “Until we get through with the KC-X opportunity and see which airframe we get and see what opportunities we have down the road to look at a follow-on to AWACS, JSTARS, and the Rivet joint … I think we’ll be okay,” Moseley said. The Air Force had previously zeroed in on using the Boeing 767 as the E-10 platform. That airplane is competing with the Northrop Grumman-EADS KC-30 in the refueling contest. The heavy ISR aircraft fleet numbers about 84 aircraft, including reserve component systems. Replacing all of them—sans their equipment—would cost about $24 billion at today’s list prices.