The Convair F-106 Delta Dart was the primary all-weather interceptor aircraft

Interceptor aircraft

An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...

 for the United States Air Force

United States Air Force

The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

 from the 1960s through the 1980s. Designed as the so-called "Ultimate Interceptor", it has proven to be the last dedicated interceptor in USAF service to date. It was gradually retired during the 1980s, with the QF-106 drone conversions of the aircraft being used until 1998.
The F-106 emerged from the USAF's 1954 interceptor

1954 interceptor

The 1954 interceptor, formally WS-201A, was a US Air Force project to develop a dedicated interceptor aircraft that would enter service in 1954. Several aircraft were developed as part of the project, leading to the F-102 Delta Dagger, F-106 Delta Dart, XF-103 Thunderwarrior and, indirectly, the...

 program of the early 1950s as an advanced derivative of the F-102 known as the "F-102B", for which the United States Air Force placed an order for in November 1955.