hesham said:
The Burnelli X-BAB-3 attack bomber project which was involved in a competition led to develop Douglas A-20.
On the chapter of excellent bomber designs that never were, a report dated 19 September 1939 about the Burnelli X-BAB-3 design concludes to the following:
The high speed possibilities of a 0.16 scale model of the Burnelli Aircraft Corporation XB-AB-3 design were investigated in the N. A. C. A. 8-foot high speed wind tunnel at Mach numbers from 0.18 to 0.65 (...) From studies of the research made by the Burnelli Co., the NACA and the Air Corps, the Military adaptability of the basic design has the following advantages over the orthodox streamlined dead-weight fuselage.
1. The coefficient of
drag is the lowest known for any useful airplane today.
2. The coefficient of
lift is greater.
3. The lifting fuselage has
distinct advantages for the installation of power plants, bombs, armament and all other accessories over the streamlined fuselage.
4. From wind tunnel tests already conducted by the NACA and NYU
the performance is exceptionally good in every phase.
5. The design embodied
extremely good factors of safety -- considerably higher than the streamlined fuselage type.
6. The design is
simple of construction and in the opinion of the Air Corps lends itself to high speed production
better than any design and therefore the valuable time element involved in all production contracts can be taken advantage of to its fullest extent.
7. It is apparently
a cheaper airplane to build because of the time element referred to in 6 above.
(emphasis added)
A more detailed summary of the report can be read here:
http://www.aircrash.org/burnelli/xbab3.htm
It is sad that the history of aircraft procurement is ripe with similar stories of superior designs that were turned down for the wrong reasons and/or by the wrong people. In this particular case, one wonders if the USAF didn't simply want to give their regular contractors a bone to chew. And if the question was Burnelli's incapacity to have the aircraft mass-produced, it would have been easy to sub-contract it to anyone else, like the USAF soon did with every mass-produced aircraft, anyway. Or maybe that's because Burnelli was a Canadian-based, not US-based, interest?
An excellent reference online for Burnelli's designs:
http://www.burnelli.com/