Paul Lewis/WASHINGTON DC

Boeing and Sikorsky hope to launch full-scale engineering development of the delayed RAH-66 Comanche helicopter next year following the submission of a $3.1 billion proposal to the US Army. The proposal maps out a 2,000h development and qualification flight test programme to start in 2004.

The next engineering and manufacturing development (EMD) phase is to begin next April, four years after the initial prototype's first flight. The programme has progressively slipped due to funding cuts, but is being brought forward by 19 months as the result of cost and time savings.

The RAH-66 must still clear a number of exit criteria for EMD to start, including measurement of the helicopter's radar cross section, infrared signature, and a vertical rate of climb demonstration.

Boeing and Sikorsky have negotiated a basic EMD agreement with the US Department of Defense, but seek another $56 million funding for a "robust flight test programme" of the second prototype in 2000, says Bob Moore, RAH-66 deputy programme manager.

A third pre-production prototype is scheduled to fly in April 2004, with three more following in quick succession. "They will be production representative aircraft with production blades, environmental control systems, but with some equipment left out," says Moore.

The third RAH-66 will fly 495h, testing in-flight structural loads, the fourth will perform 520h of propulsion testing, 460h of armament testing will be conducted by the fifth and the sixth will be equipped with full systems and fly 439h. The second prototype will be updated with the mission equipment package.

Another nine helicopters are scheduled to be produced during the EMD phase, with four to go the army for limited user testing. One helicopter will then be used for live firing and tested to destruction. The final four RAH-66s will be used for army initial operational testing and evaluation.

The first low rate initial production (LRIP) of 14 RAH-66s is due for approval by October 2004 and will be followed by a second LRIP for 26 machines before full rate production starts in 2007.

Source: Flight International