 On 1 June 1963, a crew of the 579th was conducting a propellant loading exercise when an explosion occurred, destroying the squadron's launch complex 1.A nearly identical accident on 13 February 1964 destroyed launch complex 5, followed less than a month later, on 9 March 1964, by the destruction of launch complex 2 in another explosion.On 19 November 1964, Secretary of Defense Robert MacNamara announced Project Added Effort which would phase out that all Atlas-F missiles by the end of June 1965.