Qualified Flying Instructor (abbr. QFI) is a term mainly used in the UK and commonwealth Military, Army, Navy and Air Force for a person who has passed the appropriate course before being allowed to instruct in an aircraft. In the USA and elsewhere, the equivalent term is "IP" (Instructor Pilot). For helicopters, the UK term is QHI (Qualified Helicopter Instructor).
QFI and QHI instructional categories are normally awarded by the Central Flying School (CFS) of the UK Royal Air Force, a unit that can trace its history back to 1916 when it was formed under Commander (RN) Smith-Barry. The CFS awards a number of levels of instructional categories including B2 (newly graduated flying instructor), B1, A2 and the highest category, A1. Graduates of the CFS with an A2 category are allowed to put the initials "cfs" after their name and those with an A1 category, "cfs*".
The UK CFS was formed at the grass airfield of Upavon on Salisbury plain, moving to Wittering near Stamford and then an airfield with runways, Little Rissington, west of Oxford. Other moves have included to Cranwell and Leeming.