The Republic F-105 Thunderchief is an American fighter-bomber that served with the United States Air Force from 1958 to 1984. Capable of Mach 2, it conducted the majority of strike bombing missions during the early years of the Vietnam War; the only American aircraft to have been removed from combat due to high loss rates. It was originally designed as a single-seat, nuclear-attack aircraft; a two-seat Wild Weasel version was later developed for the specialized Suppression of Enemy Air Defenses (SEAD) role against surface-to-air missile sites. The F-105 was commonly known as the "Thud" by its crews.

Suppression of Enemy Air Defenses (SEAD, pronounced ), also known in the United States as "Wild Weasel" and (initially) "Iron Hand" operations, are military actions to suppress enemy surface-based air defenses, including not only surface-to-air missiles (SAMs) and anti-aircraft artillery (AAA) but also interrelated systems such as early-warning radar and command, control and communication (C3) functions, while also marking other targets to be destroyed by an air strike. Suppression can be accomplished both by physically destroying the systems or by disrupting and deceiving them through electronic warfare. In modern warfare, SEAD missions can constitute as much as 30% of all sorties launched in the first week of combat and continue at a reduced rate through the rest of a campaign. One quarter of American combat sorties in recent conflicts have been SEAD missions. Despite generally being associated with aircraft, SEAD missions may be performed using any means, including through actions by ground forces.