C-17 Globemaster III

Mission

The C-17 Globemaster III is the newest, most flexible cargo aircraft to enter the airlift force. The C-17 is capable of rapid strategic delivery of troops and all types of cargo to main operating bases or directly to forward bases in the deployment area. The aircraft is also able to perform tactical airlift and airdrop missions when required. The inherent flexibility and performance characteristics of the C-17 force improve the ability of the total airlift system to fulfill the worldwide air mobility requirements of the United States.

The ultimate measure of airlift effectiveness is the ability to rapidly project and sustain an effective combat force close to a potential battle area. Threats to U.S. interests have changed in recent years, and the size and weight of U.S.-mechanized firepower and equipment have grown in response to improved capabilities of potential adversaries. This trend has significantly increased air mobility requirements, particularly in the area of large or heavy outsize cargo. As a result, newer and more flexible airlift aircraft are needed to meet potential armed contingencies, peacekeeping or humanitarian missions worldwide. The C-17 was designed and built with this new world order in mind.

Features

The operational requirements impose demanding reliability and maintainability of the C-17 system. These requirements include an aircraft mission completion success probability of 92 percent, only 20 aircraft maintenance manhours per flying hour, and full and partial mission capable rates of 74.7 and 82.5 percent respectively. The Boeing warranty assures these figures will be met.

The C-17 measures approximately 174 feet (53 meters) long with a wingspan of 169 feet, 10 inches (51.76 meters). The aircraft is powered by four fully reversible Pratt & Whitney F117-PW-100 engines (the commercial version is 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 requirement 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 both equipment and 102 paratroopers.

The design of the aircraft lets it operate through small, austere airfields. The C-17 can take off and land on runways as short as 3,000 feet (914 meters) and as narrow as 90 feet (27.4 meters) wide. Even on such narrow runways, the C-17 can turn around using a three-point star turn and its backing capability.

Background

The C-17 made its maiden flight on Sept. 15, 1991, and the first production model was delivered to Charleston Air Force Base, S.C., on June 14, 1993. The 17th Airlift Squadron, the first squadron of C-17s, was declared operationally ready Jan. 17, 1995. The Air Force is programmed to receive a total of 120 C-17s by the year 2005. The bulk of the inventory will be at Charleston AFB and McChord AFB, Wash. C-17s will also be at Altus AFB, Okla. and an Air National Guard unit at Jackson, Miss.

The aircraft is operated by the Air Mobility Command with current operations at the 437th Airlift Wing and the 315th Airlift Wing (Air Force Reserve).

General Characteristics

Primary Function: Cargo and troop transport
Prime Contractor: Boeing Company
Power Plant: Four Pratt & Whitney F117-PW-100 turbofan engines
Thrust: 40,440 pounds, each engine
Wingspan: 169 feet 10 inches (to winglet tips) (51.76 meters)
Length: 174 feet (53 meters)
Height: 55 feet 1 inch (16.79 meters)
Cargo Compartment: length, 88 feet (26.82 meters); width, 18 feet (5.48 meters); height, 12 feet 4 inches (3.76 meters)
Speed: 450 knots at 28,000 feet (8,534 meters) (Mach .74)
Service Ceiling: 45,000 feet at cruising speed (13,716 meters)
Range: Global with in-flight refueling
Crew: Three (two pilots and one loadmaster)
Maximum Peacetime Takeoff Weight: 585,000 pounds (265,352 kilograms)
Load: 102 troops/paratroops; 48 litter and 54 ambulatory patients and attendants; 170,900 pounds (77,519 kilograms) of cargo (18 pallet positions)
Unit Cost: $180 million (FY96 constant dollars)
Date Deployed: June 1993
Inventory: unavailable