Production deliveries of an eventual 285 planes began in 1965: 284 for the USAF, and a company demonstrator later delivered to National Aeronautics and Space Administration (NASA) for use as an airborne observatory.

[3] During the spring of 1960, the USAF released Specific Operational Requirement 182, calling for a new aircraft that would be capable of performing both strategic and tactical airlift missions.

[4] The strategic role demanded that the aircraft be capable of missions with a radius of at least 3,500 nautical miles (6,500 km) with a 60,000 pounds (27,000 kg) load.

In comparison to the firm's previous utility transport, the turboprop-powered Lockheed C-130 Hercules, it was considerably bigger, as well as possessing greater speed and more power.

[7] In terms of its basic configuration, the Model 300 was a large airlifter, furnished with a T-tail and a high-mounted swept wing, under which a total of four pod-mounted TF33 turbofan engines were fitted.

[4] President John F. Kennedy's first official act after his inauguration was to order the development of the Lockheed 300 on 13 March 1961, placing an initial contract for five aircraft for test and evaluation, to be designated the C-141.

The prototype C-141A serial number 61-2775 was manufactured and assembled in record time, having been rolled out of Lockheed's factory at Marietta, Georgia on 22 August 1963.

[12] Detailed presentations on the SC.5/41 and SC.5/45 proposals were reportedly made to both British Overseas Airways Corporation (BOAC) and to the Royal Air Force (RAF) respectively, but no orders were placed.

It is powered by an arrangement of four TF33 turbofan engines, each capable of generating up to 21,000 pounds-force (93 kN) of thrust; these were installed in pods beneath the high-mounted swept wing.

[18] Even following the arrival of large numbers of C-141s in the Vietnam theatre, the type was never able to replace the C-124 Globemaster II fully due to its inability to transport outsize equipment in-theatre; this situation was later addressed by the introduction of the even larger C-5 Galaxy.

[2][19] The final duties performed by the C-141 in the conflict were repatriation flights, bringing home thousands of American prisoners of war (POWs).

[22] During October 1973, both the C-141 and the larger C-5 Galaxy airlifted supplies from the United States to Israel during the 1973 Yom Kippur War as part of Operation Nickel Grass.

[21] Despite an early belief that the advantages of the turbojet over preceding propeller-driven cargo aircraft would render the latter obsolete, service experiences with the C-141 found that there was still a useful role for turboprop-driven utility transports such as the Lockheed C-130 Hercules.

[24] Specifically, the C-141 fleet was troubled by seemingly random cracking through the wing area, which was, according to a report compiled by the Government Accountability Office (GAO), sometimes attributable to stresses imposed under certain types of missions undertaken.

[25] During the late 1970s, the USAF opted to commence a series of major upgrades to the C-141 fleet; not only was work started on a life extension program but, in 1977, the service also accepted a proposal from Lockheed to stretch several aircraft.

[27] In order to provide sufficient C-141s to meet intense demands, all scheduled maintenance activities were postponed, while the planned peacetime flight hours of the fleet were doubled.

[22] By 1992, shortly following the end of Desert Storm, according to a GAO report, the C-141 fleet had, on average, nearly reached its 30,000 flight hour rated service life.

The GAO warned that, should another event on the scale of Desert Storm break out, the USAF would probably experience a significant shortage in airlift capabilities due to the high fatigue state of the fleet, and noted that the C-17 Globemaster III intended to eventually replace the C-141 was experiencing delays.

Between 2004 and 2006, multiple C-141s assigned to the Air Force Reserve's 445th Airlift Wing (445 AW) at Wright-Patterson AFB were deployed to Iraq and Afghanistan, where they were typically engaged in the medical evacuation (MEDEVAC) mission to repatriate wounded service members.

[34] There are 15 C-141s, including the "Hanoi Taxi", now on static display at various air museums around the United States, all other airframes were retired to the "boneyard" at Davis-Monthan AFB, Arizona, where they were scrapped.

To correct the perceived deficiencies of the original model and utilize the C-141 to the fullest of its capabilities, 270 in-service C-141As (vast majority of the fleet) were stretched, adding needed payload volume.

[4] This variant introduced some of the first glass cockpit technology to the aircraft, as well as improving reliability by replacing some mechanical and electromechanical components with more modern electronic equivalents.