It is located 5 nautical miles (9.3 km; 5.8 mi) northeast of the city of London, Ontario and is classified as an airport of entry by Nav Canada.

Site surveys and consultations took place and on 9 September 1939, at the start of World War II, work began on a new airport located near Crumlin.

Runways 14-32 and 05-23 were paved and ready for use by July 1940 and the Royal Canadian Air Force established RCAF Station Crumlin on part of the airport.

Improvements made during this time include: British Commonwealth Air Training Plan operations ended on 31 December 1944 with the closure of No.

This detachment had twenty three members and test flew De Havilland Mosquitos built in Toronto before they were flown overseas.

Two runways were listed as follows: [10] After World War II RCAF reserve or auxiliary squadrons were given the task of defending Canada's major cities.

Air Defence Command reformed 2420 Aircraft Control and Warning (Auxiliary) Squadron at London on 1 July 1956.

RCAF Station London opened in 1950 to support a NATO Induction and Training Centre, later moved to Centralia.

As a tribute to this period, a Canadair CT-133 aircraft in former Royal Canadian Air Force livery is mounted in front of the main terminal building.