sentences:  Several U.S. companies were in the process of building hovertrain systems based on technology licensed from the French Aérotrain project, known under the U.S. term "Tracked Air-Cushion Vehicle", or "TACV", and these were in the process of being set up at the TTC.Several models of proposed developments were shown at Transpo.These included models of Garrett AiResearch's wheeled linear induction motor (LIM) testbed vehicle, drawings of Grumman Aircraft's and General Electric's TACV proposals, and a full-sized mock-up of a futuristic Rohr design.