On the 17th of March 1947, a prototype of the United States’ first jet-powered bomber, the North American Aviation XB-45 Tornado, 45-59479, made a one-hour maiden flight at Muroc Army Airfield (later, Edwards Air Force Base) with company test pilot George W. Krebs at the controls. 

The XB-45 was 74 feet (22.555 meters) long with a wingspan of 89 feet, 6 inches (27.279 meters) and overall height of 25 feet, 2 inches (7.671 meters). It had an empty weight of 41,876 pounds (18,994.6 kilograms) and maximum takeoff weight of 82,600 pounds (37,466.7 kilograms).

The three prototypes were each powered by four Allison J35-A-7 turbojet engines rated at 4,000 pounds of thrust each. The maximum speed was 494 miles per hour (795 kilometers per hour) at Sea Level, 516 miles per hour (830 kilometers per hour) at 14,000 feet (4,267.2 meters) and 483 miles per hour (777 kilometers per hour) at 30,000 feet (9,144 meters). The service ceiling was 37,600 feet (11,460.5 meters).

The production B-45A Tornado was heavier and had better performance. It was operated by two pilots and carried a bombardier/navigator and a tail gunner. It was 75 feet, 4 inches (22.962 meters) long with a wingspan of 89 feet (27.127 meters) and overall height of 25 feet, 2 inches (7.671 meters).

The bomber’s empty weight was 45,694 pounds (20,726.5 kilograms) and maximum takeoff weight was 110,000 pounds (49,895.2 kilograms).

Four General Electric J47-GE-13 turbojet engines, rated at 5,200 pounds of thrust at Sea Level, were installed in nacelles which were flush with the bottom of the wings.


 
 

North American Aviation XB-45 45-59479 makes a low pass over the runway. (Photo by US Air Force)


The Tornado had a maximum speed of 570 miles per hour (917 kilometers per hour). Its service ceiling was 46,400 feet (14,142.7 meters) and it had a range of 1,000 miles (1,600 kilometers).

The bomb load was 22,000 pounds (9,979 kilograms). Two M3 50-caliber Browning  machine guns were mounted in the tail for defense.

The B-45 served with both the United States Air Force (USAF) and the UK Royal Air Force (RAF). 143 were built, including three XB-45 prototypes.

On 20 September 1948, the first production B-45A-1-NA Tornado, 47-001, was put into a dive at Muroc in California (USA) to test the design load factor. An engine exploded, which tore off several cowling panels. These hit the horizontal stabilizer, damaging it. The B-45 pitched up, and both wings separated due to the G load. The prototype had no ejection seats and George Krebs, who had made the first flight in the XB-45, and Nicholas G. Picard were both killed.


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Text Author: Bryan R. Swopes