Cover bears 30p United Nations stamp cancelled with BFPS 2480 for the 21st Anniversary of the BAe Hawk.
Cover has been flown from DTEO Llanbedr in Hawk XX154 on the 21st Anniversary of its First Flight. The sortie took in Boscombe Down where the aircraft had been tested prior to its introduction into RAF service, overflew BAe Dunsfold where the aircraft was designed and developed and the first flight took place and finally BAe Brough current home of Hawk production.

During the 1960s fast-jet training was carried out in the Jet Provost and Gnat followed by operational conversion training in two seat hunters and Lightnings. The Gnat imposed limitations on yhe size of pilot that could fly in it and it could not carry weapons. The Hunter T7 trainer represented very old technology and hunter airframes suitable for conversion to trainers had become very scarce. In preparation of this replacement Hawker Siddeley  Aviaton had already prepared a design study and realised that a jet trainer that could also be modified for an operational role could open up an enormous overseas market. The Hawker Siddeley HS1182 was chosen under Air Staff Requirement 397 and an order placed for  176 for the RAF. There were no prototypes but the first six aircraft would be used for initial testing and the aircraft would be refurbished and put into service.
The HS1182 had true trans-sonic dive performance, each of the seats was equipped with a Martin Baker MK10 rocket assited ejection seat. The rear being raised above the front seat. The name Hawk was chosen in August 1973 and a year later XX154 the first pre-production frame was ready for flight.
With Duncan Simpson at the controls it took to the air on the 21st August 1974. Fifty-three minutes later it landed.  The first two Hawk T1s were delievered to 4 Flying Training School at RAF Valley on 4 November 1976. The next units tp be re-equipped were 1 Tactical Weapons Unit at Brawdy and then 2 at Chivenor. At the end of five years of flying the MoD decided to take advantage of the initial design concept and over 80 Hawks were modified to carry a pair of AIM-9 Sidewinder air-to-air missiles. This programme was completed in 1987 and caused the designation of the modified aircraft to Hawk T1A.
In 1980 the Red Arrows convered from Gnats to the Hawk, a specially designed centre line pack being used to produce the coloured smoke used in their display.
Three hawks joined the fleet of the Empire Test Pilots' school in 1981, one of which xx341 being modified as a variable stability aircraft.
Hawker Siddeley had become part of British Aerospace and the company built a demonstrator aircraft to aid its overseas sales. This was the first of the new Hawk 50 Series.
In 1981 Hawker Siddeley won the fiercely fought contest for the United States Navy VTX-TS trainer gaining the contract for 302 T45a Goshawks as the navalised variant is known.
In 1993 the withdrawal of the Canberras of 100 Squadron commenced and their role taken over by a mixture of Hawk T1s and T1As. The Canberra TT18s of the Fleet Requirements and Direction Unit were also withdrawn from service and by mid 1995 seven Hawk T1s had been transferred from RAF flying training schools to take over the task. Cover has been signed by

Duncan Menzies Soutar Simpson OBE CEng FIMechE FRAeS
Chief Test Pilot HSA Dunsfold 1970-1977

He joined the De Havilland Aeronautical Technical School in 1945 and was there until 1948. The 3 year design course was extended by 6 months at the company's request.His practical experience was in Experimental Department at Hatfield 1946-1947 where he worked on DH106 DH108, Ghost-Vampire, Hornet, Mosquito and Dove aircraft. He joined the Aerodynamics department in 1947. He joined the RAF at 6 Flying Training School in 1949. He was awarded the Flying Trophy and Eustace Broke Loraine Trophy. He was with 222 Naval Squadron between 1950 and 1953 being Adjutant in 1951 and Deputy Flight Commander 1952-1953. He worked with the Day Fighter Development Unit at Central Fighter Establishment in 1953/4 and underwent trials on Meteor, Vampire, Venom, Sabre, Swift and Hunter. He joined Hawker Aircraft Limited in 1954 as a Test Pilot.
Between 1954 and 1962 he worked on the production and development flying of Hunter aircraft and production testing of the Sea Fury.

Gordon Thomas Hudson CEng FRAeS
Chief Designer Hawk 1971-1976

He was an engineering apprentice with Folland aircraft between 1939 and 1944. He later became junior draughtsman and technician being involved in detail design, aerodynamics. Under WEW Petter he was the Stressman Gnat prototype and Midge 1950-1952 and was the Chief Stressman Gnat Fighter 1952-1957.
He was Chief Structural Engineer and subsequently Deputy Chief Designer (Hamble) covering the Gnat trainer and in latter capacity responsible for detail design P1154 between 1957-1965. After the cancellation of the major British military aircraft projects in 1965 he transferred to HSA Kingston upon Thames.
He was the Assistant Chief Designer (airfram) for co-ordination design and structurs on P1127 Harrier 1965-1966.
he later became head of Technical Services responsible for Stress Office, Structural and Systems testing, systems engineering, Dynamics and aeroelasicity on P1127 1966-1969.
He was the Chief Designer on the Hawk 1971-1976 and the Chief Project Engineer Harrier 1976-1981.

Professor Keith Gordon Hodson MBE CEng FRAeS
Assistant Chief Designer Hawk 1971-1978

He was the Development Engineer on Vampire, Venom, Sea Venom and Sea Vixen at De Hailland 1953-56.
1956-1962 He was with Folland Aircraft Company Chilbolton and was Senior Flight Test Engineer on Gnat fighter and trainer. Between 1962 and 1962 he was with Folland Aircraft Company at Hamble and he was the Senior Design Engineer on Gnat Trainer and Folland Escape System and was involved with the introduction of Gnat Trainer to the RAF Jet Pilot Training System.
Between 1965 and 1969 he was Design Engineer in charge of Gnat and Folland Esacpe System. Between 1969 and 1971 he was Head of Preliminary Design P1182 which was later renamed Hawk. Between 1971 and 1978 he was Assistant Chief Designer Hawk and was involved with Design, Development, Service Release and introduction to the RAF Jet Pilot training system.
Between 1978 and 1982 he was with British Aerospace Military Aircraft as Assistant Chief Project Engineer Hawk and was involved in the development on the Hawk and hawk variant proposal for the US Navy. In 1982 he was the Divisional Project Manager T45A Gosahawk in association with McDonnell Douglas.