The successful inservice operation of the Hawk aircraft in both flying training and weapons training roles as well as the Red Arrows aerobatics team led, in 1987, to the RAF requesting BAe to undertake a study to assess the possibility of extending the life of the airframe. A number of life extension targets were discussed, finally settling at 10200 Operational Hours, which equated to 15000 hours when viewed in terms of the normal acceleration design spectrum and 25000 Landings. The main components of the life extension programme were:- a). the installation of a new wing standard to the Full Scale Fatigue Test, (FSFT), and its continuation as the Life Extension Fatigue Test, (LEFT). b). the assessment of items/components not fitted to the FSFT, such as the aileron which was tested separately and the flaps which had been cleared analytically. c). the assessment of build concessions (～5000), inservice modifications and repairs which were cleared against the original design requirements and again were not fitted to the FSFT. d). the development of modification, inspection and replacement strategies as required. The volume of work generated from b) and c) in particular demanded that an efficient and systematic approach was developed, including the widespread use of Operational Loads Measurement (OLM) data and coupon testing where necessary. This paper outlines the procedures and philosophies developed during the Hawk life extension programme, highlighting any particular difficulties or innovative solutions.
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