The decision by the US Department of Defense to cut procurement of the Boeing Sikorsky RAH-66 Comanche by almost half has shaved $10 billion off the programme cost, but increased the helicopter's projected unit cost to $32.2 million. The US Army is also making it clear that the newly approved plan for a 650-strong fleetfalls short of the requirement for equipping its future Objective Force and leaves it reliant on the Boeing AH-64D Apache Longbow and a yet to be identified companion unmanned air vehicle (UAV).
Maj Gen John Curran, commander of the US Army Aviation Centre, says the service has three options. The army can continue to push for more RAH-66s with the goal of a "pure Comanche" fleet, revert to the original plan of a mixed RAH-66 and AH-64D fleet, or operate Comanches alongside an all-new Apache replacement. "Within the Objective Force, 650 does not address all of our requirements. Analysis tells us we need 819 helicopters," he says.
The next opportunity to consider RAH-66 numbers will come in May when the decision on full-scale development of the Future Combat System (FCS)is due to be taken. FCS includes a family of armoured vehicles and multi-tier UAVs, and will form the backbone of the Objective Force.
The army had planned to buy 1,213 Comanches at the rate of 72, or perhaps 96, a year to support the fielding from 2008 of the first Objective Force units. The planned annual purchase will slow to 60 and if FCS slides two years, as seems likely, this will weaken rather than strengthen the case for more RAH-66s, concedes the army.
As part of the restructuring plan, the army has been told to accelerate development of a companion UAV with the initial Block 1 version of Comanche having control of the UAV's sensors. Block 2 machines will have full control of the vehicle in the air. For every unit of 12RAH-66s, there will be up to eight UAVs depending onsize and capability. "We've not yet decided on the companion UAV, but it does buy us a wedge of funding, starting in 2006 to address this. It might be the [AAI] Shadow 200 or even Unmanned Combat Air Rotorcraft," says Col Robert Birmingham, US Army RAH-66 programme manager.
Meanwhile, the army wants more performance margin from the Comanche's LHTEC T800-802 turboshafts and 1,900kW (2,400shp) rated transmission. While the powerplant will exceed all of the requirements, including a 500ft/min (2.5m/s)vertical rate of climb, the army is looking at increasing the transmission rating to 1,940kW to improve payload-range performance. The army says the T800-802 exceeds the 2,200h meantime between replacement goal, and some of this extra life could be traded to allow the engine to operate at a higher temperature.
Source: Flight International
