Steve's Airshow World - Aircraft Factfile and Recognition Guide

Aircraft Factfile and Recognition Guide - C-17 Globemaster III

Background

The C-17 is the newest airlift aircraft to enter the Air Force's inventory. 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 theater airlift missions when required.

The C-17's system specifications impose a demanding set of reliability and maintainability requirements. These requirements include an aircraft mission completion success probability of 93 percent, only 18.6 aircraft maintenance man hours per flying hour, and full and partial mission capable rates of 74.7 and 82.5 percent respectively for a mature fleet with 100,000 flying hours.

The C-17 measures approximately 174 feet long with a 170-foot wingspan. 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 40,900 pounds of thrust. The thrust reversers direct the flow of air upward and forward to avoid ingestion of dust and debris.

The aircraft is operated by a crew of three (pilot, copilot and loadmaster). 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, outsized combat equipment. The C-17 is also able to airdrop paratroopers and cargo.

Maximum payload capacity of the C-17 is 170,900 pounds, and its maximum gross takeoff weight is 585,000 pounds. With a payload of 130,000 pounds and an initial cruise altitude of 28,000 feet, the C-17 has an unrefueled range of approximately 5,200 nautical miles. Its cruise speed is approximately 450 knots (Mach .77).

The design of this aircraft lets it operate on small, austere airfields. The C-17 can take off and land on runways as short as 3,000 feet and as narrow as 90 feet wide. Even on such narrow runways, the C-17 can turn around by using its backing capability while performing a three-point star turn. Maximum use has been made of off-the-shelf and commercial equipment, including Air Force standardized avionics.

The C-17 made its maiden flight on Sept. 15, 1991. The aircraft is operated by the Air Mobility Command with initial operations at Charleston AFB, SC, with the 437th Airlift Wing and the 315th Airlift Wing (Air Force Reserve). The C-17 program is managed by the Aeronautical Systems Center, Wright-Patterson AFB, Ohio. C-17s are also based at McChord AFB, WA with the 62nd Airlift Wing and the 446th Airlift Wing (Air Force Reserve). C-17 training is conducted at Altus AFB, OK. Based on the initial batch of 120 aircraft, ninety-six aircraft will be based at Charleston AFB and McChord AFB, with the number split evenly between the two bases. The other twenty-four aircraft are and will be based at Altus AFB, OK and go with an Air National Guard unit in Jackson, MS. Another batch of 14 aircraft are slated to be based in McGuire AFB, NJ, with the 305th Air Mobility Wing and the 514th Air Mobility Wing (Air Force Reserve) starting in the summer of 2004. Other C-17s can be found at Dover AFB, DE; Travis AFB, CA; March ARB, CA; Elmendorf AFB, AK; and Hickam AFB, HI.

Foreign operators of the C-17 include NATO (3), Canada (4), Australia (4), the United Kingdom (6, with a seventh on order), Qatar (2), and orders have been received from the United Arab Emirates (6) and a possible order from India (up to 10).

Specifications

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) (51.75 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; 36 litter and 54 ambulatory patients and attendants; 170,900 pounds (77,519 kilograms) of cargo (18 pallet positions)
Unit Cost: $236.7 million (FY98 constant dollars)
Date Deployed: June 1993

Sources: USAF C-17 Globemaster III Factfile, The Aviation Zone, Federation of American Sciences