The Lockheed C-141 Starlifter is a military strategic airlifter in service with the United States Air Force. Introduced to replace slower piston-engined cargo planes such as the C-124 Globemaster II, the C-141 was designed to a 1960 requirement and first flew in 1963; production deliveries of an eventual 248 began in 1965, and the aircraft is still in service almost 40 years later, although the USAF plans to withdraw the C-141 from service in 2006 when sufficient C-17 Globemaster III aircraft are available.

The original Starlifter model, the C-141A, could carry 138 passengers, 80 litters for wounded, or ten standard 463L pallets with a total of 62,700 pounds (28,900 kg) of cargo. The C-141 could also carry a Minuteman missile. It was soon discovered that the aircraft's volume capacity was relatively low in comparison to its lifting capacity; it generally ran out of physical space long before it hit its weight limit.

To correct this and use the C-141 to the fullest, the whole fleet of aircraft were stretched, producing the C-141B. Additional 'plug' sections were added before and after the wings, lengthening the fuselage by 23 ft 4 in (7.11 m) and allowing the carriage of 103 litters for wounded, 13 standard pallets, 205 troops, 168 paratroopers, or an equivalent increase in other loads. Also added at this time was a boom receptacle for inflight refueling. The conversion program took place between 1977 and 1982. It was estimated that this stretching program was the equivalent of buying 90 new aircraft, in terms of increased capacity.

More recently, 63 aircraft have been upgraded to C-141C status, with improved avionics and navigation systems, to keep them up-to-date until C-17s are available to replace them.

In 1994, thirteen C-141Bs were given SOLL II (Special Operations Low-Level II) modifications, which gave the aircraft a low-level night flying capability, enhanced navigation equipment, and improved defensive countermeasures. The USAF operates these aircraft for the Air Force Special Operations Command. These aircraft are slated to be replaced by special-purpose new-build C-17s.

On 16 September 2004 the C-141 left service with active duty USAF units, being confined to reserve units for the remainder of its service life. As of September 25th, 2005, there are only 8 C-141 aircraft still flying (All from Wright-Patterson AFB) near Dayton, Ohio. One of them is the same aircraft that was used at the end of the Vietnam War to repatriate American POWs from North Vietnam, and will soon be moved to the National Museum of the United States Air Force, also at WPAFB.