15 August 1962: American Airlines’ Captain Eugene M. (“Gene”) Kruse set a National Aeronautic Association Class C-1 record for Speed Over a Commercial Air Route, East to West Transcontinental, when he flew a Boeing 720B Astrojet from New York to Los Angeles, 2,474 miles (3,981.5 kilometers), in 4 hours, 19 minutes, 15 seconds, at an average speed of 572.57 miles per hour (921.46 kilometers per hour). 55 years later, this record still stands.
The National Aeronautic Association has placed Captain Kruse’ record on its “Most Wanted” list: long-standing flight records that it would like to see challenged. Rules require that a new record exceed the old by at least a 1% margin. The performance needed to establish a new record would be 578.30 miles per hour (930.68 kilometers per hour).
The Boeing 720B was a variant of the Model 707, intended for short to medium range flights. It had 100 inches (2.54 meters) removed from the fuselage length and improvements to the wing which decreased aerodynamic drag. The 720B was the first commercial jet airliner to use more efficient turbofan engines, substituting four Pratt & Whitney JT3D for the 707’s JT3C-6 turbojets. Boeing built 154 Model 720 and 720B airliners from 1959 to 1967.
The Boeing 720 was operated by a flight crew of four and could carry up to 149 passengers. It was 136 feet, 2 inches (41.504 meters) long with a wingspan of 130 feet, 10 inches (39.878 meters) and overall height of 41 feet, 7 inches (12.675 meters). The airplane had an empty weight of 103,145 pounds (46,786 kilograms) and Maximum Takeoff Weight of 220,000 pounds (99,790 kilograms).
The JT3C turbojet engines produced 12,000 pounds of thrust, each, while the more efficient JT3D turbofans used for the 720B produced 17,000 pounds of thrust, each.
The Boeing 720B had a maximum cruise speed was 611 miles per hour (983 kilometers per hour) and its maximum speed was 620 miles per hour (998 kilometers per hour). Range at at maximum payload was 4,370 miles (7,033 kilometers).
The last flight of a Boeing 720B took place on 9 May 2012, when an airliner used by Pratt & Whitney Canada as a test aircraft was placed in the National Air Force Museum of Canada at Trenton, Ontario.
© 2016, Bryan R. Swopesby