Nomenclature is assigned to:. The flight test program went well, though the second prototype was lost on 3 June when its hydraulic and electrical systems failed. United States Armed Forces.

Some subsystems will have the designation for the system they belong to. Carrier air group commanders were not entirely pleased with the Vigilante.

While the pilot had a good forward view, the "bombardier-navigator" in the back seat had only a small window to each side. Heath simply neutralized the controls; once the Vigilante reached thicker air halfway through its fall, it naturally adopted a nose-down attitude, and Heath was able to relight the engines. F-4 pilots often had to call to the Vigilante pilots to slow down so the fighter could keep up.