From: Chad Irby

snip

The big problem for the German program was Heisenberg. Before the war,
he'd calculated some fission cross-sections incorractly, and apparently
never recalculated them. He thought the mass for a chain reaction was
something on the order of forty *tons*.

snip



OK, we know the bombs didn't need 40 tons of either uranium or plutonium.

Given the size and weight of Fatman or Littleboy type bombs just what would the
Germans, let alone the Japanese, have used to deliver them? Other than by
submarine or surface vessel I can't imagine how they would have been able to.

Dan, U. S. Air Force, retired