DALLAS — Today, in 1978, the last variant of the Lockheed L-1011 TriStar, the -500, took to the skies for the first time.

The long-range variant was launched in August 1976 and could fly up to 6,100 nm (11,260 km). It had a 4.1 m (13 ft 6 in) shorter fuselage than its predecessors at 164 feet 2 inches (50.04 m), a larger wingspan at 164 feet 4 inches (50.09 m), a higher max take-off weight, and powerful new RB211–524 engines.

Lockheed made use of emerging technologies in the late 1970s. Other improvements included active-load-control ailerons and noise-reducing Frisbee fairing. This was named after Lloyd Frisbee, the Lockheed engineer who designed it.

Launch Customer

British Airways (BA) became the launch customer of the -500, receiving its first example on April 27, 1979. It entered service on May 7, 1979, between London Heathrow (LHR) and Abu Dhabi (AUH). The type remained in the fleet until October 1991.

In December 1982, the British Royal Air Force purchased six Tristar 500s from BA. These initially operated in a strategic transport role as Tristar C.MK's one-passenger aircraft. They were later converted to air-to-air refuellers.

Delta Air Lines (DL) was the first US airline to fly the -500. It was introduced to service on June 17, 1979, between Atlanta (ATL) and Frankfurt (FRA). The type would become the backbone of DL's growing international network.

Production of the -500 ended in 1983 after 50 of the type had been built.

Featured image: Lockheed used the prototype L-1011 (N1011) as the testbed for improvements and future derivatives of the Tristar.