B-29 with in-line engines

[seacue]

I've certainly heard of engine problems on the B-29, but this is the first I'd heard that in-lines were tried as a fix.

Spirit of Lincoln: 1944 | Shorpy Historical Photo Archive (http://www.shorpy.com/node/16436)

[Rory57]

That is a nice picture.:)

The XB39. See Boeing XB-39 Superfortress - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/XB-39_Superfortress)

for in flight pictures and a bit of wiki-info.

[Allan Lupton]

Seems to have been rather a waste of time - the Allison 3420-11 should have been good for around 2600 h.p. each at 25000 ft. but in the XB-39 it appears they had to run without the turbo-superchargers so would have delivered a lot less.