[2] In response to the attack on Bien Hoa Air Base on 1 November 1964 the Joint Chiefs of Staff (JCS) proposed a B-52 strike on Phúc Yên, but this was opposed by senior Johnson Administration officials.

[3]: 59 At the start of Operation Rolling Thunder in March 1965, U.S. aircraft were forbidden to go within a radius of 40 nautical miles of Hanoi, which included Phúc Yên, although these restrictions were gradually reduced as the campaign continued.

[3]: 96 In May 1965 Il-28 bombers were identified at Phúc Yên, as these aircraft were capable of conducting airstrikes on South Vietnam the JCS again proposed a B-52 strike on Phúc Yên and nearby SA-2 sites, but once again approval was denied for fear that such an attack might provoke increased Soviet and PRC support for North Vietnam or even PRC intervention in the war.

[5] On 24/5 October 1967 in response to increased VPAF fighter interceptions USAF, Navy and Marine aircraft attacked Phúc Yên for the first time.

[9] Phúc Yên, Kép and Hoa Lac were targeted on the first night of Operation Linebacker II on 18 December 1972 to suppress fighters that might otherwise intercept US attack aircraft.