The United Kingdom flight inspection unit was set up at Croydon as a branch of the Air Ministry just after the war. It was designed to:
- Provide communication flying for the government (flying VIP's)
- Carry out flying test for issue of a pilot's "B" licence
- Monitor and calibrate the radio aids to navigation for a civil aircraft
At that time, the unit's aircraft were:
- 8 Avro 19s (Ansons)
- 2 Tiger Moths
- 1 Percival Proctor
- 1 Miles Gemini
The staff (all ex RAF) consisted of:
- 10 Pilots
- 5 Navigators
- 6 Radio Operators
In the early 1950's more aircraft were purchased for pilot testing but navigation aid inspection was still made using the Ansons. A new crewmember, the NAVAID inspector was introduced giving more technological approach to calibration. The unit was renamed the "Civil Aviation Flying Unit" (CAFU).
2 DH Doves were bought and fitted for navigation aid calibration.
4 more Doves were purchased and fitted out as Instrument Rating Aircraft.
In 1952, 3 Percival Princes were purchased for navigation aid inspection but these were found to have no advantages over the Doves.
The Ansons were phased out in the mid 1950s.
In 1959, a Percival President was purchased and mainly used for developing a tracking system for ILS inspection.
In 1969, 2 HS 748 aircraft were purchased and fitted with calibration equipment designed by CAFU and a HS 125 was purchased for pilot training and VIP flying.
In the early 1970's all flight inspection work was taken over by the HS 748s.
In the mid 1970's another HS 748 was purchased to be used for pilot training and VIP flying.
A committee was set up to examine the structure of CAFU and its administration. In 1977 it was decided that commercial activities and VIP flights would cease. The administration of CAFU was divided up, with flight inspection going to National Air Traffic Services (NATS).
During the 1980s the old CAFU organisation slowly changed and in 1988 NATS took responsibility for all flight inspection duties and re-named the unit the Flight Calibration Unite (FCU), with only the 2 HS 748s being retained.
In November 1991, a private company was approved to make flight inspections in the UK, operating in competition with NATS FCU.
In April 1992, NATS FCU was made into a CAA Strategic Business Unit (SBU) and was usually known as the CAA Flight Inspection Service (FIS).
In October 1996, the CAA FIS was sold to private industry.
This resulted in the present situation. All UK flight inspection (civil and military) is made by two private companies. Both companies are required to hold approvals from the CAA Safety Regulation Group (SRG) and are subject to regular audits to confirm compliance to CAA requirements.