The aircraft was designated A, the twelfth in a series of internal design efforts for "Archangel", the aircraft's internal code name. The CIA's representatives initially favored Convair's design for its smaller radar cross-section , but the A's specifications were slightly better and its projected cost was much lower. The companies' respective track records proved decisive. Convair's work on the B had been plagued with delays and cost overruns, whereas Lockheed had produced the U-2 on time and under budget.
In addition, Lockheed had experience running a "black" project. The A was produced from to and flew from to It was the precursor to the twin-seat U. Air Force YF prototype interceptor , M launcher for the D drone , and the SR Blackbird , a slightly longer variant able to carry a heavier fuel and camera load. The A began flying missions in and its final mission was in May ; the program and aircraft were retired in June. The program was officially revealed in the mids.
The aircraft itself came to be called that as well. Bissell Jr. We agreed Under Project Gusto the designs were nicknamed "Archangel", after the U-2 program, which had been known as "Angel". As the aircraft designs evolved and configuration changes occurred, the internal Lockheed designation changed from Archangel-1 to Archangel-2, and so on. These names for the evolving designs soon simply became known as "A-1", "A-2", etc.
However, these concepts never met the required range. Design concept A featured two General Electric J turbojets with 2-D underwing inlets and had better mission radius than concepts A-4 thru A These designs had reached the A stage when the program was reviewed.
The A was competing against a Convair proposal called Kingfish , of roughly similar performance. However, the Kingfish included a number of features that greatly reduced its RCS, which was seen as favorable to the board.
