Although the Lockheed TriStar airliner did not fare particularly well in the civilian market, the RAF was quick to note the potential of this aircraft for transport and tanker duties in the aftermath of the Falklands War and thus aquired a number of surplus British Airways and Pan-Am units which were then converted for military use by Marshall of Cambridge. These differ little from their civilian counterparts other than by the installation of twin hose-and-drogue inflight-refuelling units in the rear fuselage (only one can be used at the same time though). The dual-role units also have a large cargo door on the port side of the fuselage for freight, in addition all RAF TriStars have a permanent refuelling probe above the cockpit. The TriStar has been used in recent conflicts such as Kosovo, Afghanistan and Iraq, serving both RAF and US units, but will likely be eventually replaced in the next decade by the A330 MRTT.

The first civilian L-1011 TriStar was flown on 16 November 1970 and production lasted until 1983. After the Falklands War, the RAF aquired surplus L-1011-500 airliners from BA and converted them to TriStar K.1 tankers and KC.1 tanker/transports (it should be noted that the tankers retain passenger capability), the main difference being a prominent cargo door on the latter. A second acquisition of Pan Am units resulted in the TriStar C.2 and C.2A with are pure passenger transports used for ferrying troops and for medical evacuation.