Key point: The Avro 730 had much in common with the American Lockheed SR-71 Blackbird and predated it by a year or two.
Had history turned out differently, the first Mach 3 spy plane of the Cold War might have been British rather than American.
The U.S. Air Force first deployed the legendary SR-71 Blackbird in January 1966. Yet Britain had plans for a high-altitude, supersonic reconnaissance aircraft that could have flown as early as 1965.
The Avro 730 was born during the early 1950s, in the golden twilight of manned strategic bombers before ICBMs made their fiery debut. To support its force of nuclear-armed V- bombers—the Valiant, Victor and Vulcan—the Royal Air Force called for a high-altitude, long-range reconnaissance jet that could fly at a speed of at least Mach 2.5 (1,918 miles per hour).
Just how ambitious these goals were can be seen by the fact that Britain would not field its first supersonic fighter, the Mach 2–capable Lightning, until 1959. And to make development of the spy plane even more complicated, the RAF eventually added a requirement that the aircraft become a reconnaissance bomber capable of dropping nuclear weapons.
In 1955, the RAF awarded a development contract to Avro, the aircraft manufacturer behind the Vulcan as well as the legendary Lancaster bomber of World War II. The four-turbojet Avro 730 actually looked somewhat like the SR-71, with a long, slender fuselage, except that the 730 had canards—mini-wings—near the nose.
Maximum altitude would have been sixty-six thousand feet, and maximum range 4,280 nautical miles at a top speed of Mach 2.5, according to author Tony Butler in his book British Secret Projects: Jet Bombers Since 1949. The fully fueled aircraft would have weighed 146 tons, with half the aircraft’s weight taken up by fuel. The two-man crew would have sat in a cockpit that only had two small side-facing windows. For visibility during takeoff and landing, the pilot would have relied on a retractable periscope.