Boeing B-17F radar bombing through clouds over Bremen, Germany, on Nov. 13, 1943.

Each task force had one flail tank. As the flail tanks crested the hill, they passed through our infantry line directly into the minefields. Although the tanks had to contend not only with mines but with an extremely soggy field, they made an initial good showing. The flying chains detonated several mines, and the explosions created additional craters. But finally, due to the combination of the muddy fields and the fact that the horsepower needed to turn the flail took too much power away from the tracks, both flail tanks became mired in the mud.