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From what I've read and from photos I've seen, the pilot or G/O could drop bombs individually or all at once. On the Fee, if memory serves, there was a lever you pulled that released the bombs, and the farther you moved the lever the more bombs you dropped. Pull it to the first detent and the first bomb dropped, pull it to the second detent and the next one dropped, and so on. Pull it all the way back and they all fell. Of course, in the early part of the war the bombs were simply dropped by hand over the side of the cockpit.
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