The green fire training thingy was built in the late 1990s, my civil engineering colleagues were involved in the project and a similar objet d'art at Stansted. If I recall correctly it was subsequently moved to make room for the Virgin hangar. The Trident was "owned" by a schoolfriend's BA management dad and was originally used for tug training I think. As was the Comet - or am I thinking of the ex-Dan-Air example at Gatwick?