General Technician Workshops General Technician Workshops ( GTW ) is the title of a ground trade within the Royal Air Force . The primary role of GTW tradesmen is the manufacture and repair of aircraft components and associated equipment . GTWs are usually employed within Station workshops at front line flying stations . The trade currently has a strength of 130 personnel . History . The evolution of the workshops trade has been the result of the amalgamation of more specialist trades such as blacksmith and welder , coppersmith and metal worker , metal worker , and machine tool setter and operator . Each amalgamation occurred when the demand for a particular type of work diminished sufficiently to justify joining similar trades . One such absorption occurred in 1935 , when the trades blacksmith and welder , and coppersmith and metalworker were abolished and replaced by the trade of metal worker . Training . Phase 2 and 3 training for GTW is currently carried out at Defence College of Electro - Mechanical Engineering ( DCEME ) No 4 School of Technical Training at MOD St Athan , in the Electro Mechanical Training Flight ( EWTF ) . After the completion of phase 1 training at RAF Halton , recruits begin a 58 week training course at St Athan entailing basic engineering , sheet metal work , welding processes including oxyacetylene welding , MIG , MMA and TIG welding , Turning and Milling . During the course trainees also study key skills , technical drawing , mathematics , electrical and mechanical principals , as well as undergoing a vigorous physical training routine . On the successful completion of phase 2 training , trainees are awarded the rank of LAC and posted to an RAF station . They are also awarded City & Guilds Level 3 Progression Award in engineering fabrication , and can eventually gain an NVQ Level 3 in engineering fabrication as part of an Advanced Apprenticeship . Tradesmen may eventually be required to return to St Athan to undergo phase 3 courses including advanced welding , Sheet metal work , turning , milling , and grinding , to fulfil the qualification requirements of a permanent post or a temporary deployment . Role . The primary role of GTWs is the manufacture and repair of aircraft components , in support of the squadrons at any particular RAF Station . They also provide support for ground support equipment and military transport , as well as general station support . The processes carried out in this role include sheet metal work fabrication using manual forming techniques and brake press forming , TIG , MIG , MMA and oxyacetylene welding , turning and milling using conventional and CNC machines , and surface and cylindrical grinding . GTWs are employed in most RAF Flying stations in the Station workshops , but in recent years have also been deployed to support overseas operations including Op TELIC and Op HERRICK . RAF Stations with GTW posts are : • RAF Halton • RAF Wittering • RAF St . Mawgan • RAF Odiham • RAF Coningsby • RAF Waddington • RAF Marham • RAF Benson • RAF Brize Norton • RAF Cottesmore • DMRC Headley Court • RAF Leeming • RAF Kinloss • RAF Leuchars • RAF Lossiemouth • RAF Saint Athan • RAF Aldergrove • RAF Akrotiri • RAF Mount Pleasant • RAF Gibraltar