Nash & Thompson was a British engineering firm that developed and produced hydraulically operated gun turrets for aircraft. As part of Parnall Aircraft it was also an important manufacturer of hydraulic-powered radar scanners used on radar systems such as H2S and AI Mark VIII.
Nash & Thompson was established in 1929 at Kingston upon Thames by business partners Archibald Goodman Frazer Nash and Esmonde Grattan Thompson
Nash & Thompson developed the hydraulic gun turrets that Frazer-Nash invented and his designs were consequently numbered in a series prefixed with "FN".
In May 1935 they formed Parnall Aircraft taking over George Parnall & Company and Hendy Aircraft Company. Thompson was appointed managing director and Frazer Nash technical director.
The company's major competition in the UK was from Boulton & Paul, which had licensed the designs of the French company S.A.M.M. (Societe d'Application des Machines Motrices). The FN turrets used hydraulic power produced by the aircraft's engine: the BP designs used individual hydraulic pumps for each turret supplied from the aircraft's 24 volt electrical system.
Nash & Thompson built a wide range of turrets for aircraft. All were powered hydraulically and carried 0.303 inch (7.7 mm) Vickers K or Browning machine guns, except where noted. Many were built by Parnall Aircraft with which they merged in 1935.
FN-1 – "lobster back" partially enclosed turret for Hawker DemonFN-4A – four gun rear turretFN-5 – two gun nose turret on Avro Manchester, Short Stirling and Vickers WellingtonFN-5A – two gun nose turret on Avro LancasterFN-7 – two gun dorsal turret on Blackburn Botha, Manchester, Short Sunderland, StirlingFN-9 – two gun retractable "dustbin" ventral turret on Wellington, rarely fitted.FN-10 – two gun tail turret on early-model Wellington and Armstrong Whitworth WhitleyFN-11 – two gun retractable nose turret in SunderlandFN-13 – four gun tail turret in SunderlandFN-16 – single Vickers 'K' gun front turret in WhitleyFN-17 – two gun retractable "dustbin" ventral turret on Whitley, rarely usedFN-20 – four gun tail turret on Lancaster, Wellington, Stirling and WhitleyFN-21A – two gun retractable "dustbin" ventral turret on Manchester, rarely usedFN-25 – two-gun retractable "dustbin" ventral turret for the Wellington I based on the FN-17FN-50 – two gun dorsal turret ("Centre Gun Turret") on Lancaster, late-model StirlingFN-51 – two gun dorsal turret on early-model Handley Page HalifaxFN-54 – two gun rearward firing chin turret on Bristol Blenheim Mk.IV and Bristol BeaufortFN-64 – two gun ventral turret ("Under Gun Turret") on Lancaster with periscopic sight, rarely fittedFN-77 – retractable ventral turret fitted with Leigh Light for the Wellington and Warwick based on the FN-25FN-82 – two gun (0.5 inch (12.7 mm) Browning) tail turret on late-model LancasterFN-120 – four gun tail turret; refinement of the FN-20 weighing 40 lb (18 kg) less; used on late-model Lancaster and WellingtonFN-121 – four gun tail turret on late-model Lancaster fitted with Village Inn gun-laying radar; also used without AGLR on Wellington and WarwickFN-150 – an improved two gun dorsal turret, based on the FN-50, and fitted to many Lancasters
