Reliability and maintainability are two outstanding benefits of the C-17 system.
Current operational requirements impose demanding reliability and maintainability. These requirements include an
aircraft mission completion success probability rate of 92 percent, only 20 aircraft maintenance man-hours per
flying hour, and full and partial mission availability rates of 74.7 and 82.5 percent, respectively. The Boeing
warranty assures these figures will be met.
The C-17 measures 174 feet long (53 meters) with a wingspan of 169 feet, 10 inches (51.75 meters).
The aircraft is powered by four, fully reversible, Federal Aviation Administration-certified F117-PW-100 engines
(the military designation for the commercial Pratt & Whitney PW2040), currently used on the Boeing 757. Each
engine is rated at 40,440 pounds of thrust. The thrust reversers direct the flow of air upward and forward to
avoid ingestion of dust and debris. Maximum use has been made of off-the-shelf and commercial equipment,
including Air Force-standardized avionics.
The aircraft is operated by a crew of three (pilot, copilot and loadmaster), reducing
manpower requirements, risk exposure and long-term operating costs. Cargo is loaded onto the C-17 through
a large aft door that accommodates military vehicles and palletized cargo. The C-17 can carry virtually
all of the Army's air-transportable equipment.
Maximum payload capacity of the C-17 is 170,900 pounds (77,519 kilograms), and its
maximum gross takeoff weight is 585,000 pounds (265,352 kilograms). With a payload of 160,000 pounds
(72,575 kilograms) and an initial cruise altitude of 28,000 feet (8,534 meters), the C-17 has an
unrefueled range of approximately 2,400 nautical miles. Its cruise speed is approximately 450 knots
(.74 Mach). The C-17 is designed to airdrop 102 paratroopers and equipment.
The design of the aircraft allows it to operate through small, austere airfields.
The C-17 can take off and land on runways as short as 3,000 feet (914 meters) and only 90 feet wide
(27.4 meters). Even on such narrow runways, the C-17 can turn around using a three-point star turn and its backing capability.