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When Northrop's first company was purchased by Douglas, it became their El Segundo division. Along with the facilities, Douglas also inherited a few projects and ongoing programs from Northrop. The most famous one was the Model 8A (Army A-17 and A-33) but there was also a small bomber design, the Model 7, now the Douglas Model 7, the prototype of which was completed and submitted in a USAAC attack competition (Circular Proposal CP38-385, March 1938) against the North American NA-40 (forerunner of the Mitchell), Stearman X100, Bell Model 9 (an Airacuda derivative with V-1710 engines) and the Martin 167 (which would become the Maryland).
CP38-385 did not require prototypes, only proposals, yet Douglas, North American and Stearman produced one each. However, none of them proved satisfactory to the Air Corps, and soon a modified version of the Circular Proposal (CP39-460) was issued, and this time prototypes were mandatory. A prototype of the Martin 167 (Model 167W) was completed. It was a much more streamlined and advanced design, produced by James S. McDonnell, Jr. during his stint at Martin and incorporating most of the Air Corps specifications from the start, so that the prototype didn't have to undergo any major redesign after evaluation by the Air Corps. Only Bell declined to join the second phase of the competition. They did produce a more advanced attack design, the Model 17, but it remained unbuilt.
The three prototypes initially submitted had to be reworked to CP39-460, the most obvious change being a complete redesign of the nose section. The NA-40 and Douglas Model 7, which both had full noses, were redesigned to feature a glazed gunner position, becoming the NA-40B (or NA-40-2) and Model 7B respectively. The Stearman X100 (now known internally as the Boeing Model 329), which alone featured an all-round glazed cockpit for both gunner and pilot was also reworked: cockpit and nose were stepped to reduce the glazing and make the nose more sturdy, but also to improve pilot visibility.
The Boeing/Stearman prototype became the XA-21 and the Martin prototype became the XA-22. The North American NA-40B was not found satisfactory for the attack role and didn't even get a designation. The Douglas 7B didn't have time to get the "XA-20" designation that was presumably reserved for it because it crashed during tests. In all logic, considering Martin's lead in bombers and the quality of their design, and now the loss of the Douglas prototype, the odds seemed to be in favor of the Model 167. And yet it was the Douglas 7B that obtained the best evaluation of all four aircraft (905 points out of 1000) and was declared the winner, being produced as the A-20 Havoc (Model DB-7 series).
The losing Martin 167W got only 718 points in the evaluation — it didn't have the tricycle gear favored by the USAAC Committee for increased visibility. However, it didn't fare too badly, being produced in quantity for France and then Britain as the Model 167F/167B Maryland. As for the unfortunate NA-40B, it enjoyed an even greater career, becoming the prototype of the B-25 Mitchell medium bomber...
CP38-385 did not require prototypes, only proposals, yet Douglas, North American and Stearman produced one each. However, none of them proved satisfactory to the Air Corps, and soon a modified version of the Circular Proposal (CP39-460) was issued, and this time prototypes were mandatory. A prototype of the Martin 167 (Model 167W) was completed. It was a much more streamlined and advanced design, produced by James S. McDonnell, Jr. during his stint at Martin and incorporating most of the Air Corps specifications from the start, so that the prototype didn't have to undergo any major redesign after evaluation by the Air Corps. Only Bell declined to join the second phase of the competition. They did produce a more advanced attack design, the Model 17, but it remained unbuilt.
The three prototypes initially submitted had to be reworked to CP39-460, the most obvious change being a complete redesign of the nose section. The NA-40 and Douglas Model 7, which both had full noses, were redesigned to feature a glazed gunner position, becoming the NA-40B (or NA-40-2) and Model 7B respectively. The Stearman X100 (now known internally as the Boeing Model 329), which alone featured an all-round glazed cockpit for both gunner and pilot was also reworked: cockpit and nose were stepped to reduce the glazing and make the nose more sturdy, but also to improve pilot visibility.
The Boeing/Stearman prototype became the XA-21 and the Martin prototype became the XA-22. The North American NA-40B was not found satisfactory for the attack role and didn't even get a designation. The Douglas 7B didn't have time to get the "XA-20" designation that was presumably reserved for it because it crashed during tests. In all logic, considering Martin's lead in bombers and the quality of their design, and now the loss of the Douglas prototype, the odds seemed to be in favor of the Model 167. And yet it was the Douglas 7B that obtained the best evaluation of all four aircraft (905 points out of 1000) and was declared the winner, being produced as the A-20 Havoc (Model DB-7 series).
The losing Martin 167W got only 718 points in the evaluation — it didn't have the tricycle gear favored by the USAAC Committee for increased visibility. However, it didn't fare too badly, being produced in quantity for France and then Britain as the Model 167F/167B Maryland. As for the unfortunate NA-40B, it enjoyed an even greater career, becoming the prototype of the B-25 Mitchell medium bomber...