The Boeing-Sikorsky RAH-66 Comanche is basically an advanced 5-blade armed reconnaissance and attack helicopter designed for the United States Army. During the early 1980s, the U.S. Army began formulating a requirement for the replacement of its helicopters then in service, resulting in the Light Helicopter Experimental program. In 1991, the Boeing-Sikorsky team was chosen to produce prototypes. The Comanche would incorporate stealth technologies, featuring a number of designs previously untried. Continue reading for more.
In 1982 the U.S. Army started the Light Helicopter Experimental (LHX) program to replace UH-1, AH-1, OH-6, and OH-58 helicopters. It took six years, until 1988, before the request for proposal (RFP) was issued, in which the requirement was changed to a reconnaissance helicopter. The program’s name was changed to Light Helicopter (LH) in 1990, and the next year, the Boeing-Sikorsky team was selected as the contest winner and received a contract to build four prototypes for a demonstration and evaluation phase.
4. Maiden Voyage
The first Comanche prototype was rolled out of the Sikorsky Aircraft’s helicopter production facility on May 25, 1995, before being transferred to West Palm Beach, Florida, for flight testing. The prototype, piloted by Bob Gradle and Rus Stiles, made its 39-minute maiden flight on January 4, 1996. The flight was originally planned for August 1995, but was delayed by structural and software problems.
The RAH-66 was powered by two LHTEC T800 turboshaft engines. Its fuselage was 43 feet (13 m) long and made of composite material. It was designed to fit more easily onto transport ships, enabling it to be deployed to hot spots quickly.
The RAH-66 was intended to be a stealth helicopter; it incorporated multiple techniques to reduce its radar cross-section (RCS) and other areas of visibility. Its outer surfaces were faceted and had radar-absorbent material (RAM) coatings and infrared-suppressant paint applied; with these measures, the Comanche’s RCS was 360 times smaller than the AH-64 Apache attack helicopter. The Comanche’s acoustic signature was noticeably lower than comparative helicopters; this was partly achieved through the all-composite 5-blade main rotor and pioneering canted tail rotor assembly
On February 23, 2004, the U.S. Army announced their decision to cancel the RAH-66 Comanche program after determining the upgrades would be required for the RAH-66 to survive current anti-aircraft threats. They also planned to use the program’s funds to speed up development of unmanned aerial vehicles (UAVs). The Comanche program cost approximately $6.9-billion USD at the time of its termination.