C 17

The Boeing (formerlyMcDonnell Douglas) C-17 Globemaster III is a large military transport aircraft. The C-17 was developed for the United States Air Forcefrom the 1980s to the early 1990s by McDonnell Douglas. The aircraft carries on the name of two previous United States military cargo aircraft, the C-74 Globemasterand the C-124 Globemaster II. The C-17 is used for rapid strategic airliftof troops and cargo to main operating bases or forward operating basesthroughout the world. It has the ability to rapidly deploy a combat unit to a potential battle area and sustain it with on-going supplies. The C-17 is also capable of performing tactical airlift, medical evacuationand airdrop missions.

The C-17 is operated by the US Air Force, the United Kingdom,Australia, Canada, NATO, and Qatar, while the United Arab Emirateshas placed orders.

In the 1970s, the US Air Force began looking for a replacement for theC-130 Hercules tactical airlifter. The Advanced Medium STOL Transport(AMST) competition was held, with Boeing proposing the YC-14, andMcDonnell Douglas proposing the YC-15. Though both entrants exceeded specified requirements, the AMST competition was canceled before a winner had been selected. The Air Force subsequently started the C-X program to develop a larger AMST with longer range to augment its strategic airlift.

In recent years the size and weight of U.S. mechanized firepower and equipment have grown, which has significantly increased air mobility requirements, particularly in the area of large or heavy outsize cargo. The C-17 can airlift such cargo fairly close to a potential battle area.

The C-17 is powered by four fully reversible, F117-PW-100 turbofanengines (the Department of Defense designation for the commercial Pratt and Whitney PW2040, used on the Boeing 757). Each engine is rated at 40,400 lb_f (180 kN) of thrust. The thrust reversers direct the flow of air upward and forward. This reduces the probability of foreign object damage and provides reverse thrust capable of backing the aircraft. Additionally, the C-17's thrust reversers can be used in flight at idle-reverse for added drag in maximum-rate descents.

Specifications (C-17)

General characteristics

• Crew: 3: 2 pilots, 1 loadmaster
• Capacity:
  
  • 102 troops with standard centerline seats or
  • 134 troops with palletized seats or
  • 36 litter and 54 ambulatory patients or
  • Cargo, such as an M1 Abrams tank
• Payload: 170,900 lb (77,519 kg) of cargo distributed at max over 18463L master pallets or a mix of palletized cargo and vehicles
• Length: 174 ft (53 m)
• Wingspan: 169.8 ft (51.75 m)
• Height: 55.1 ft (16.8 m)
• Wing area: 3,800 ft² (353 m²)
• Empty weight: 282,500 lb (128,100 kg)
• Max takeoff weight: 585,000 lb (265,350 kg)
• Powerplant: 4× Pratt & Whitney F117-PW-100 turbofans, 40,440lbf (180 kN) each
• Fuel capacity: 35,546 US gal (134,556 L)

Performance

• Cruise speed: Mach 0.76 (450 knots, 515 mph, 830 km/h)
• Range: 2,420 nmi (2,785 mi, 4,482 km)
• Service ceiling: 45,000 ft (13,716 m)
• Max wing loading: 150 lb/ft² (750 kg/m²)
• Minimum thrust/weight: 0.277
• Runway requirement: 3,500 ft (1,064 m) long by 90 ft (27.4 m) wide