<p>On 4 September 1957 the private venture prototype (N329J) of Lockheed's Model 1329 utility transport took to the air from Burbank, California. The design and development of the type had been initiated to meet a USAF requirement for a UCX (utility transport, experimental) which the service had intimated it would purchase 'off the shelf' as soon as budgeting allowed.
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<p>Originated by a team headed by the renowned Clarence L. ('Kelly') Johnson, the airplane soon to be named JetStar had a circular-section pressurized fuselage for a crew of two and 10 passengers, a low set wing with 30 degrees sweepback and swept tail surfaces with the tailplane mounted part way up the fin. The powerplant was to be the Curtiss-Wright TJ37 turbojet of 4,850 lb thrust, a licence-built version of the Bristol Siddeley Orpheus. The two prototypes each had one of these engines mounted in pods either side of the rear fuselage, and in this configuration the type was adopted by the USAF in October 1959 as the C-140.
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<p>A decision by Curtiss-Wright to abandon the TJ37 resulted in Lockheed having to adopt the Pratt & Whitney JT12A-6 engine. This offered less power, so four engines were adopted. The second prototype was refitted with the two pairs of JT12A-6s, and at the same time was fitted with large fuel tanks at the mid-span position. This fixed the basic configuration of the first production model, the JetStar 6, which also had a slightly lengthened fuselage and pneumatic deicing boots fitted on the leading edges.
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<p>In June 1960 five JetStar 6s were ordered as C-140As (59-5958/59-5962) for the MATS Airway and Air Communications Service (later Air Force Communications Command). These were fitted with onboard equipment to test and calibrate landing and navigation aids at USAF bases around the world. In this role they served into the 1980s, before the task was passed to the FAA. Five additional JetStar 6s were procured as C-140Bs (62-4197/62-4201) as missions support transports, followed by six VC-140Bs (61-2488/61-2493) with VIP interiors for staff transport. The C-140Bs were soon redesignated as VC-140Bs, and the fleet was active ferrying high-ranking officers and their staff until the 1980s when replacement by the C-20 was completed. Civilian sales of the JetStar continued with the uprated JetStar 8 and the Garrett-engined JetStar II.
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<hi style=hdr1>Specification</hi>
<hi style=hdr2>Lockheed—C-140A JetStar</hi>
<list style=aflst>
<item><hi format=bold>Type:</hi> utility transport and navaid calibration
<item><hi format=bold>Powerplant:</hi> four Pratt & Whitney JT12A-6 turbojet engines, each rated at 3,300 lb
<item><hi format=bold>Performance:</hi> maximum speed 566 mph; service ceiling 37,400 ft; range 2,120 miles
<item><hi format=bold>Weights:</hi> empty 22,074 lb; maximum take-off 42,000 lb
<item><hi format=bold>Dimensions:</hi> wing span 54 ft 5 in; length 60 ft 5 in; height 20 ft 5 in; wing area 542.5 sq ft
