Optimum bombing height
 

What was the approximate optimum bombing height for a 4 engined heavy bomber bombing say a factory to get the bombs on target? And for a 2 engined bomber?

What was the main determinant of actual bombing altitude in WW2? eg the 26,000' of B17s, the 18,000' of Lancasters at night, the 7000' of Marauders etc: was it the weather, winds, engine performance, fuel range, flak, fighters, bomb site performance?

How was it calculated?

The optimum altitude wold be as low as possible (moderated only by concern about self-harm from the exploding bombs). The higher up you go, the more the chance that cross-winds would blow the bombs off-target.

The main reason that bombers usually flew as high as they could was to avoid Flak, and also I expect to make the defending fighters work harder to climb up to their altitude (the higher a bomber flies, the greater the performance advantage needed by the fighters to make an interception - and the sooner they would run out of fuel).

Tony Williams: Military gun and ammunition website and discussion
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