They built 9,984 B-25 Mitchells that flew 63,177 sorties and dropped 84,980 tons of bombs. That's 1.3 tons per sortie. The loss rate per sortie was 0.0060, or 166 sorties per loss.
They built 5,288 B-26 Marauders that flew 129,943 sorties and dropped 169,382 tons of bombs. That's 1.3 tons per sortie. The loss rate per sortie was 0.0070, or 143 sorties per loss. Some say the B-26 was a handful to fly. From hearing guys that flew it, it wasn't. What was unusual was that it came over the fence some 25 - 35 mph faster than other, comparable aircraft of the time. So it SEEMED harded, but all that was happening was that the airstrip was disappearing a bit quicker on rollout.
Those numbers are for the ETO and the tons are 2,000 pound tons (short tons). Offhand I'd say they were about even with the B-25 being much more versatile. It was used for recon, maritime patrol, had a ton of guns fitted for attack, and was safer around a short airstrip. But you would have to work some to prove one was significantly better than the other.
Both were good planes to be in during WWII with significantly lower loss rates per sorties than any heavy that I am aware of.
Interestingly enough, the Douglas A-26 Invader compares favorably, though with significantly less use. It only flew 11,567 sorties and dropped 18.054 tons of bombs for an average of 1.4 tons per sorties. The loss rate was 0.0058, or 173 sorties per loss. It got to the war fairly late but did well with respect to other US medium bombers ... though it was an Attack Plane by designation.
The Douglas A-20 dropped 0.5 tons per sorties and had a loss rate roght between the B-25 and B-26.
Again, these are ETO numbers.
Found the numbers here:
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