The first training course, held by the Commandant, Wing Commander Samuel "Sammy" Wroath with G. Maclaren Humphreys, a civilian, as Technical Instructor, was initially attended by 18 pilots, drawn largely from the Royal Air Force (RAF) and the Fleet Air Arm of the Royal Navy but included three civilian attendees (all from the Bristol Aeroplane Company). Five students found the standard of maths required on the course to be too high and left within the first week; the 13 students who completed the first course comprised 11 from the RAF (including one American, Sqn Ldr JC Nelson, who was serving with one of the Eagle Squadrons) and two from the FAA. Of those who attended No. 1 Course, five eventually died testing aircraft.