In May of 1944 the USAF cancelled its B-35 programme, foreseeing the inadequacy of this bomber in the future. At the same time, however, it authorised the completion of two of these to be modified and fit with jet propulsion engines. The first YB-49 took flight on October 21, 1947 powered by eight Allison J35 turbojets, which, in the end, were not very reliable. The many problems notwithstanding, the YB-49 did show promise, with the exception of its autonomy factor, reduced due to the high fuel consumption of that generation’s engines. One of its great advantages was something that in those days was not considered very important: the fact that the YB-49 often disappeared from the radar screens because of its weak marking. The problem which eventually signed the fate of this promising aircraft was the excessively thick airfoil section which limited its cruising speed, just when this factor seemed to be the most important quality needed for a combat airplane.

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