During the Cold War years, Convair’s delta-wing F-106A was the fastest and most lethal all-weather interceptor in the U.S. Air Force inventory. The F-106A, when lightly loaded, approached the magic 1-to-1 thrust-to-weight ratio—a characteristic coveted by fighter pilots everywhere. With a 24,500-pound-thrust afterburning Pratt & Whitney J75-P-17 engine pushing an airframe only slightly heavier than the engine thrust output, this 1950s-era airplane had an impressive initial climb rate of 30,000 feet per minute and a zoom-climb altitude above 70,000 feet. As a result of the “thermal barrier” created by friction heat on the ship’s skin and Plexiglas canopy, its airspeed was limited to Mach 2.31 (1,525 mph).