Airframe Profile: C-17 Globemaster III

ByTSgt Greg C. Biondo, Airman Magazine

The C-17 Globemaster III has proven to be a workhorse in the U.S. Air Force’s airlift arsenal. Utilizing strategic airlift capabilities the aircraft is able to deliver troops and cargo to bases in contingency environments and forward operating bases in austere locations. The airframe’s versatile platform can perform tactical airlift and airdrop missions and be configured to conduct aeromedical evacuations when required.

Operated by eight countries and NATO, the C-17 has delivered cargo in every worldwide operation since the 1990s.

DEVELOPMENT

In 1979, the Defense Department started the Cargo-Experimental program, as the Air Force was looking for a large air mobility platform with in-flight refueling capabilities for global reach missions. McDonnell Douglas won the contract in 1981 with its proposal to build the C-17.

NASA played a huge role in the development of the C-17 contributing research and technology that had been made available to the industry over four decades. The powered-lift, developed by researchers at the NASA Langley Research Center in the mid-1950s, gave the aircraft close to double the lift coefficient of a conventional transport airframe by positioning the engines and flaps in a way that directed the exhaust downward. The development of this technology gave the C-17 short take off and landing capabilities allowing it to takeoff and land on runways as short as 3,500 feet and 90 feet wide. The aircraft is also able to turn around on these narrow runways using a three point star turn and its reverse capability.

U.S. Air Force C-17 Globemaster III cargo aircraft, assigned to the 437th Airlift Wing and the 315th AW, fly over the Blue Ridge Mountains in Virginia, as part of the largest formation of aircraft deployed from a single base to demonstrate the US Air ForceÕs strategic airlift and airdrop capabilities. (Photo // Staff Sgt. Jacob N. Bailey)

The supercritical wing, winglets, fly-by-wire system, engine performance enhancements and composite materials used throughout the aircraft were all developed in partnership with NASA.

The C-17 made its maiden flight Sept. 15, 1991. The first production model was delivered to Charleston Air Force Base, now known as Joint Base Charleston, South Carolina, June 14, 1993, and the first C-17 squadron was declared operational Jan. 17, 1995.