In 1951, Republic Aviation began a
project (AP-63) to develop a supersonic tactical fighter-bomber
to replace the F-84F.
The result was the F-105 Thunderchief, which later gained the
affectionate nickname "Thud." The prototype YF-105A
made its first flight on October 22, 1955. The first production
aircraft, an F-105B, was delivered to the United States Air
Force in May 27, 1958.
A supersonic aircraft capable
of carrying conventional and nuclear weapons internally as well
as externally, the F-105B was the heaviest, most complex fighter
in the USAF inventory when it became operational. F-105s were
produced only in the "B," "D" and
"F" series (later, some "F"s were modified
to become F-105Gs).
The first ten F-105Bs were delivered as pre-production test
aircraft. Some were briefly used by the Thunderbirds,
but when an aircraft broke up in flight, the team
reverted back to the F-100D. The F-105D could carry over 12,000 pounds of ordnance, a
heavier bomb load than a World War II B-17.
Up to 8,000 pounds could be carried internally in the bomb bay.
The F-105D was used extensively in the Vietnam
War. It flew 75 percent of the air strikes against North
Vietnam during its first four years. The last F-105D was
withdrawn from USAF service on July 12, 1980. 833 Thunderchiefs