HelicoptersC/NPhotos The AS.350BB Squirrel HT.1 is used for basic, single-engine rotary wing training by a RN shadow unit at the Defence Helicopter Flying School (DHFS). @ (optional) Send Units YearsUnitsBase 1997/18RN 705 NAS RAF Shawbury RNAS Culdrose1997/18Ministry of Defence (MoD) DHFS RAF Shawbury AAC Middle Wallop RAF Valley