531 Squadron was formed at RAF West Malling, Kent on 8[1] September 1942, from No.

Instead of operating only Turbinlite and -rudimentary- Airborne Intercept (AI) radar equipped aircraft (Havocs and Bostons) and working together with a normal nightfighter unit, such as in their case with the Boulton Paul Defiants of No.

32 Squadron RAF in the Flight,[3] the unit now also flew with their own Hawker Hurricanes.

The squadron moved to RAF Debden, Essex on 2 October 1942, but returned to West Malling a week later.

[2] It was disbanded at West Malling on 25 January 1943,[1] when Turbinlite squadrons were, due to lack of success on their part and the rapid development of AI radar, thought to be superfluous.