Boeing XB-15 - Operational History

Operational History

The single prototype was assigned to the 2nd Bombardment Group at Langley Field, Virginia. Following the 24 January 1939 Chillán earthquake in Chile, the prototype flew a relief mission, carrying medical supplies. Commanded by Major Caleb V. Haynes, the aircraft carried 3,250 lb (1,470 kg) of American Red Cross emergency supplies to Santiago, making only two stops along the way, at France Field in the Panama Canal Zone, and at Lima, Peru. Haynes was awarded the Distinguished Flying Cross and the Order of the Merit of Chile, and the whole crew earned the MacKay Trophy.

Haynes piloted the XB-15 again on 10 June 1939 to return home the body of Mexican flier Francisco Sarabia who had died in a crash in the Potomac River. After flying back from Mexico City, Haynes and his copilot William D. Old undertook flight tests at Fairfield, Ohio, lifting very heavy loads. They used the XB-15 to lift 22,046 pounds (10,000 kg) to a height of 8,228 feet (2,508 m), and 31,164 pounds (14,136 kg) to 6,561.6 feet (2,000.0 m), setting two world records. Haynes was awarded certificates issued by the National Aeronautics Association (NAA) for an international record for "the greatest payload carried to an altitude of 2,000 metres". The XB-15 was not very fast for a bomber but it was the fastest aircraft capable of carrying so much weight, and traveling such long distances. In July 1939, Haynes received certificates from the NAA for the establishment of an international 5,000 km (3,100 mi) speed record with a 2,000 kg (4,400 lb) payload. The latter performance also established a national closed circuit distance record of 3,129.241 miles (5,036.025 km).

Flying from Langley, the XB-15 arrived at Albrook Field in Panama on 10 April 1940 and immediately began classified bombing tests of canal lock protections, commanded by Haynes and including Captain Curtis LeMay as navigator and Lieutenant John B. Montgomery as bombardier. Of 150 bombs dropped, only 3 hit the target: a specially made bunker simulating a reinforced machine room. The few hits nevertheless led to improvements in bunker design. In early May, Haynes and LeMay made a survey flight from Panama over the Galapagos islands, the inspection including Baltra Island. Haynes piloted the XB-15 back to the US, leaving Panama on 11 May 1940.

In late 1940, the XB-15's defensive guns were removed at Duncan Field in Florida. Seats were attached so that Lend Lease aircraft ferry crews could be returned after delivery.