When dropped from (IIRC) 40,000' it was supposed to become supersonic
(original design spec). As it was dropped from a much lower altitude
(20,000'??) it didn't(?).

The Tallboys and Grandslams had a well designed ballistic shape and
could accelerate to these velocities

BackToNormal wrote:

Was half paying attention to a TV doco on the Dambusters a few mins ago
and thought I heard the narrator say the Earthquake bomb designed by
Barnes Wallis broke the sound barrie on its way down.
Comments anyone?

ronh