#a-45

"The second (left) and first (right) XB-51 aircraft at the Martin plant in Middle River. Both aircraft have the bullet tail fairings, and the second prototype (left) has RATO bottles attached. The Martin plant in the background still has the camouflage paint scheme applied during World War II. Compare the different flap and wing positions between the two aircraft."

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Concept art of the original Martin XA-45 design, which evolved into the XB-51 trijet ground attack aircraft.

"In February 1946, the United States Army Air Force (AAF) sought design proposals for an attack aircraft to replace the Douglas A-26 Invader. The Glenn L. Martin Company (Martin) responded with its Model 234, a straight-wing aircraft of a rather conventional layout, except that the engine nacelle on each wing housed a turboprop and a turbojet engine. The Model 234 had a crew of six and was forecasted to carry 8,000 lb (3,629 kg) of ordinance over 800 miles (1,287 km).

Martin was awarded a contract to develop the Model 234 on 23 May 1946, and the aircraft was designated XA-45. A few weeks later, the AAF decided to discard the “Attack” category, and the XA-45 was subsequently redesignated XB-51. The AAF then requested new requirements for the XB-51 with an emphasis on speed. The AAF’s new desired specifications for the A-26 replacement was a top speed of 640 mph (1,030 km/h) and the ability to carry 4,000 lb (1,814 kg) of ordinance over 600 miles (966 km). The new requirements necessitated a complete redesign of the XB-51, which Martin completed and submitted to the AAF in February 1947. After slight modifications, the design was somewhat finalized by July 1947. The AAF ordered two prototypes, which were assigned serial numbers 46-685 and 46-686."

Martin XB-51 formation during a low-level pass.

Date: July 11, 1951

Martin XB-51 (sn 46-686) under construction at Martin's factory in Baltimore, Maryland.

Date: 1948-49

Martin XB-51 on the cover of Model Airplane News magazine. Artwork by Jo Kotula.

Date: April 1950

A Martin XB-51 in flight.

Date: 1950s

"The Martin Aircraft Company was a bit more outlandish when they proposed using their new XB-51 medium bomber to carry two of their latest MX-771 Matador winged missiles, one on each wingtip, selling two products at one time."