The LHX (Light Helicopter X) programme, to provide the US Army with a light
scout/attack helicopter to replace the AH-1 Cobra, OH-6 Cayuse, and OH-56
Kiowa, was initiated in 1982.  The original plan was to acquire 5000
helicopters, in a mixture of LHX SCAT (scout/attack) and LHX Utility
versions; the latter was intended as a UH-1 replacement.  The utility role
was dropped, and the requirement reduced to 2096 aircraft, in 1987.  Two
consortia were awarded demonstration and validation contracts in October
1988, one consisting of Bell and McDonnell Douglas, the other Boeing and
Sikorsky.  On 5 April 1991, the Boeing/Sikorsky team was awarded a contract
for development of the LHX, now designated RAH-66A Comanche.

The programme has survived recent budget cuts; the first flight is
scheduled for September 1994, service delivery 1997.  The production total
is now expected to be 1292 aircraft, of which about one third will be the
RAH-66B version, carrying a slightly smaller version of the Longbow radar
fitted to the AH-64D Apache.

Vital statistics (RAH-66A):  fuselage length 13.22 m, rotor diameter 11.90
m, empty weight 3402 kg, max weight 7790 kg, max speed 328 km/h, range 2335
km; power plant:  two 690 kW LHTEC T800-LHT-800 turboshafts; armament:
20mm cannon, internal and external carriage for up to 14 Hellfire or 18
Stinger missiles.