Seletar Airport (IATA: XSP, ICAO: WSSL) is a civilian international airport serving the north-east region of Singapore. It is located approximately 16 km (9.9 mi) northwest from Changi Airport, the country's main airport, and about 16 km (9.9 mi) north from the main commercial city-centre. The airfield was originally opened in 1928 as RAF Seletar, a military airbase of the British Royal Air Force (RAF). The base was transferred to Singapore in 1971. The Government of Singapore intended for Seletar Airport and the surrounding areas to function as the operating aerodrome for their plan to expand Singapore's status as an industrial aviation hub, today known as the Seletar Aerospace Park. Today, Seletar Airport mostly serves turbo-prop and smaller private and business jet airlines and aircraft. It helps to serve as a secondary destination to Singapore for turbo-prop aircraft to decrease the load on Changi Airport, which has heavy air traffic (primarily passenger airlines).