Outlines of a plan to develop a new vertical heavylift aircraft that can haul 18,100-22,700kg (40,000-50,000lb) up to 800km (430nm) are due to be submitted this week by the US Army to top aides to undersecretary of defence for acquisition Michael Wynne.
"The goal is to do work that identifies the technological art of the possible for heavy vertical lift," says a Wynne memorandum dated 4 October, directing the army to provide the report within 30 days.
The report is to recommend whether the project should be led by one service arm or the joint community, and must consider whether to include NASA and the US Defense Advanced Research Projects Agency. Wynne's memo also tasks the report team to "identify funding requirements for [fiscal year 2005] through FY07 and potential funding sources".
Although not a new-programme start, the document is a breakthrough for backers of new heavylift rotorcraft technology. The current standard in the USA is the Sikorsky CH-53E Super Stallion, which can haul, at most, 14,500kg for 80km. The US Marine Corps plans to develop a follow-on, the Heavy-Lift Rotorcraft, that carries a 13,600kg external load at least 205km.
A new heavylift standard is being driven by the rise of several warfighting doctrines - including the navy's seabasing and the army's mounted vertical manoeuvre - now taking hold in the Pentagon. In broad terms, these strategies call for stationing entire army divisions afloat, plus transporting troops and equipment hundreds of kilometres inland without needing to defend roads and airstrips.
"Emerging joint concepts imply the need for a joint, vertical, heavy-lift capability," Wynne's memo says. "It is important that we know soon what system solutions are feasible and how we might employ those systems to meet capability needs."
Industry has been working on a diverse mix of candidate technologies for many years, usually in the 70,000kg take-off weight class, including the Bell Quad Tilt Rotor (QTR), a Sikorsky coaxial rotor and a fan-and-wing design by Lockheed Martin. Boeing has not disclosed the approach it is pursuing.
Propulsion approaches also vary greatly. Sikorsky believes its design can work with Rolls-Royce AE1107C engines, now installed on the Bell Boeing V-22 Osprey. But Bell's QTR will require a major leap in engine development - four 12,000shp (8,940kW) -class engines.
STEPHEN TRIMBLE / WASHINGTON DC
Source: Flight International
