In article ,
"W. D. Allen Sr." wrote:

The British needed special design spinning finless 7000 lb bombs to break
through the Ruhr Dam during WW II. Half the bombers on the mission were
lost, most before they got to the dam.

....because they had to contend with AA guns at the dams, torpedo nets,
low-level flying at night, and some tough maneuvers over a couple of the
reservoirs.

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.