The squadron conducts global deployments on behalf of the British Armed Forces and the UK Government, notably delivering emergency aid during natural disasters and supporting military operations overseas.

In May 1924, it moved to RAF Bircham Newton in Norfolk, uniquely receiving the Avro Aldershot single-engined heavy bomber.

These were replaced at the end of 1925 by twin-engined Handley Page Hyderabads, the squadron moving to RAF Upper Heyford in December 1927.

However, 99 Squadron, which had moved to RAF Mildenhall in November 1934, was obliged to retain the Heyford until October 1938, when it converted to Vickers Wellington monoplanes.

[14] It flew its first operational mission of the war on the night of 8/9 September 1939, when three Wellingtons set off from Mildenhall to drop leaflets over Germany.

[16] On 14 December 1939, 12 Wellingtons of the squadron set off for an armed reconnaissance of the Schillig Roads, hoping to attack a force of German warships spotted by a British submarine the previous night.

The unit put the new long range turboprop aircraft to use to evacuate citizens from troublespots all over the world such as Congo 1960, Kuwait 1961, Belize 1961 and Aden 1967.

One of the first high-profile missions of the squadron was the deployment of Westland Lynx helicopters and support equipment to Macedonia as part of a NATO peacekeeping force.

[24] Previously the RAF had to lease commercial heavy lifters such as the Antonov An-124 to return the aircraft to the UK, or launch a major logistical effort to allow a ferry flight.

In any case the C-17 has proved invaluable to the RAF and in December 2009, the Ministry of Defence announced its intention to acquire a seventh aircraft.

On 24 August there were 354 persons on board, and by the close of the evacuation, 436 stood as the new record and the greatest number of people ever flown on a single RAF aircraft.

99 Squadron carried the coffin of Queen Elizabeth II from Edinburgh Airport to RAF Northolt in preparation for Her Majesty's state funeral.