In 1947, Fairey Aviation started development of what was to become Britain's first 'Air to Air' guided missile. This missile was primarily designed to counter the threat posed by enemy bomber aircraft although it was also hoped that it could be used against enemy fighter aircraft.
This missile program, which was 'top secret' (for obvious reasons) was given the code name 'Blue Sky' so as to not give any indication of the purpose of the project. Only later when the project moved to the trials squadron stage was the missile called 'Fireflash'.
At the time of development, Air-launched Anti Aircraft Missile technology was in its infancy and none of the 'homing' mechanisms used on modern missile systems had been designed, so, using radar 'lock-on' technology developed during the war, the missile was designed to be a 'beam riding' missile, whereby the host fighter would lock a very narrow radar beam onto the aircraft to be attacked and after launch, the missile would centre itself onto the beam and fly along the beam until it reached the target.
By 1952, the project had developed to the stage that all the design of missile was mostly done and the missile was first flown from a test platform at the Larkhill test area on Salisbury plain.
EKCO's role in the project was to design and develop the radar suite in the host aircraft and the radar developed was an X band system using a helical Scan dish, which had a small amount of 'nod'.
Fairey Aviation described the system as 'Radar Ranging Mark 2' but this description was not accepted by EKCO who did not consider this an accurate name.
The radar had a capability of up to 10 miles in range but was only intended for use at approximately 5 miles although would be fired at about 2 miles during tests but a bit further (or shorter) in anger as the pilot chose.
The following pages are the first hand account of Ken Sims who was closely involved with the project.
