Basa began as an American bomber field. Pacific Wrecks says the US Army built Floridablanca airfield before the war for bombers; Wikipedia dates its construction to mid-November 1941 and identifies it with Del Carmen Field. That identification is not certain: Pacific Wrecks notes that a September 1944 Japanese-era map shows a “New Del Carmen Field” and that Floridablanca may have been “Del Carmen No. 2”. What the US Army’s official history makes clear is that Del Carmen was home to the 34th Pursuit Squadron on 8 December 1941, and that it was bombed on 10 December and again on 12 and 13 December, by which time the fields were strewn with wrecked aircraft.

Japanese forces took the area in late December 1941. Wikipedia says the field was an auxiliary to Clark, where kamikaze operations were conceived in 1944; Pacific Wrecks finds little evidence of heavy Japanese use and records a Ki-44 found on the field when the Americans returned in January 1945.

The Americans then enlarged it for heavy bombers. Between 16 April and 13 August 1945 the 312th Bomb Group flew A-20s and B-32 Dominators from Floridablanca — the only combat unit to fly the B-32 — and the 348th Fighter Group was here with P-47s and P-51s from 15 May to 12 July 1945, according to Pacific Wrecks. An A-20G was destroyed on the ground in a bomb-loading accident on 3 June 1945.

The young Philippine air arm took the field over in 1947: GlobalSecurity dates the transfer to 2 May, and Wikipedia says operations began on 22 August. The 6th and 7th Fighter Squadrons were activated on 24 October 1947 with US-supplied P-51D Mustangs, which flew against the Hukbalahap insurgency into the early 1950s; the 8th Fighter Squadron followed on 1 August 1951, and the units became the 5th Fighter Wing in 1952. On 20 April 1948 the base was renamed after César Basa.

The F-86F Sabre and the T-33 arrived in 1957, and the 9th Tactical Fighter Squadron, formed on 14 December 1962, took its Sabres to the Congo for the United Nations in February 1963. The F-5A followed in the mid-1960s; GlobalSecurity gives 1965, Wikipedia 1964.

Basa was also the home of the Blue Diamonds. Second Lieutenant Jose FL Gonzales formed a four-man Mustang team in 1952–1953, named the Blue Diamond in 1954 and the Blue Diamonds in 1960. They flew five P-51Ds until 1959, eight F-86Fs until 1968 and twelve F-5s until 2005, according to Wikipedia, which also records four pilots killed between 1957 and 1962. The team was largely inactive from 1975 to 1985 during the energy crisis and has not flown since the F-5 retired.

The Marcos government’s biggest fighter purchase came to Basa from 1977–1978: 25 refurbished ex-US Navy F-8H Crusaders, the most potent fighters the PAF had yet flown. GlobalSecurity says they were permanently grounded in 1988 because of maintenance costs.

Basa’s F-5As were still flying in December 1989. GlobalSecurity reports that on 1 December a squadron of them took off from Basa and strafed the rebel-held Sangley Point air base, and attacked Camp Aguinaldo on 2 December. Wikipedia names Major Danilo Atienza as the loyalist pilot killed in the operation; GlobalSecurity says his aircraft crashed.

Eighteen months later Mount Pinatubo, less than 25 km away, erupted. The USGS study of the eruption’s effects on aviation records that 15 to 20 cm of water-saturated ash collapsed buildings at Clark and Basa, and that “a squadron of 11 obsolete F-5 jets of the Philippine Air Force parked at Basa Air Base was covered by ash from the June 15 eruption.” GlobalSecurity says the grounded F-8s were damaged too and moved to Clark for storage and scrapping. Clark and Basa reopened for limited operations in 1992. The F-5 soldiered on until September 2005, when it was retired without a replacement.

For a decade after 2005 Basa had no fighters. That changed with the FA-50PH, the light combat version of the Korean T-50: the first two reached the Philippines on 28 November 2015, and Wikipedia dates the type’s arrival at Basa to 2017, when the last of the twelve were delivered. They went to war almost at once. On 26 January 2017 FA-50s of the 7th Tactical Fighter Squadron bombed militant positions at Butig, Lanao del Sur, the type’s first combat mission, and they flew throughout the siege of Marawi from May to October.

Basa also became a US base again, in all but name. It was one of five locations agreed under EDCA in March 2016, and the first EDCA facility in the country, a humanitarian assistance and disaster relief warehouse, opened here on 30 January 2019. In March 2023 work started on a PHP 1.3 billion runway rehabilitation, which Wikipedia calls the largest EDCA project to date; it was completed in November 2023 and lets the base take larger and heavier aircraft.

China has opposed the agreement. The PAF has since used Basa to host foreign fighters in the Cope Thunder series: in April 2024, during Cope Thunder 24-1, PAF and US aviators briefed civilian air traffic controllers at Basa on the FA-50PH and F-16, according to the PAF website. In June 2025 the Philippines ordered 12 more FA-50s, the Block 70, for delivery by about 2030.