Industry believes the US Air Force’s planned unmanned combat air vehicle and proposed medium-range bomber (MRB) could merge, and both companies involved in the Joint Unmanned Combat Air System (J-UCAS) programme are designing bigger versions of their demonstrators to meet the interim long-range strike requirement.
“There is some convergence of the J-UCAS and MRB requirements,” says George Muellner, Boeing Air Force Systems president. “From a scenario perspective they are very similar.” The USAF is to perform an MRB analysis of alternatives next year. This will look at an FB-22 variant of the Lockheed Martin/Boeing F/A-22 as well as unmanned systems and other options such as upgrades to the Rockwell B-1.
Boeing is building the X-45C and Northrop Grumman the X-47B for the US Air Force/Navy J-UCAS capability demonstration, but both companies confirm they are studying larger versions for the MRB requirement. In response to a long-range strike (LRS) request for information from the USAF in May last year, Boeing proposed a scaled-up 13,600kg (30,000lb) empty-weight, 3,300km (1,800nm)-range X-45D powered by a General Electric F110-class fighter engine. It was also more expensive.
“We stopped, took a look at regional jet engines and decided a refanned [GE] CF34-10 would be much more affordable,” says Darryl Davis, vice-president, global strike solutions. The resulting UCAV has “80% of the capability of the D, at 30-40% of the cost,” he says. With air-to-air refuelling, range would be 2,800km-plus. The X-45C J-UCAS demonstrator, due to fly in 2007, is an 8,200kg empty-weight vehicle with 2,000kg payload and 2,200-2,400km range.
Source: Flight International
