[Jim Oxley]

America didn't class it's bombers by weight carrying ability, but by size, armour protection and armament. Hence a four-engined bomber was classed as a Heavy Bomber.

As to load carrying ability below are listed some figures that may be of interest to you.

B-17E:
Empty Weight: 33,280lb
Loaded weight: 53,000lb
Max Bomb Load: 4,000lb
Range: 1100 miles with 4,000lb

B-17F:
Empty Weight: 34,000lb
Loaded weight: 65,500lb
Max Bomb Load: 8,000lb
Range: 1,250 miles with 6,000lb

B-17G:
Empty Weight: 38,000lb
Loaded weight: 65,500lb
Max Bomb Load: 9,600lb
Range: 1200 miles with 6,000lb

B-24D:
Empty Weight: 32,605lb
Loaded weight: 71,200lb
Max Bomb Load: 12,000lb
Range: 1400 miles with 8,000lb

B-24J:
Empty Weight: 38,000lb
Loaded weight: 71,200lb
Max Bomb Load: 12,800lb
Range: 1540 miles with 8,000lb

B-29:
Empty Weight: 71,360lb
Loaded weight: 138,,000lb
Max Bomb Load: 20,000lb
Range: 1950 miles with 20,000lb

Halifax Mk.I:
Empty Weight: 33,860lb
Loaded weight: 55,000lb
Max Bomb Load: 13,000lb
Range: 980 miles with 13,000lb

Halifax Mk.III
Empty Weight: 39,000lb
Loaded weight: 65,000lb
Max Bomb Load: 13,000lb
Range: 1260 miles with 13,000lb

Lancaster B.I:
Empty Weight: 41,000lb
Loaded weight: 72,000lb
Max Bomb Load: 14,000lb
Range: 1040 miles with 12,000lb

Lancaster B.III:
Empty Weight: 41,500lb
Loaded weight: 72,000lb
Max Bomb Load: 14,000lb
Range: 1040 miles with 14,000lb

Lancaster B.I (Special):
Empty Weight: 36,000lb
Loaded weight: 72,000lb
Max Bomb Load: 20,000lb - Grand Slam
Range: 660 miles with 20,000lb

Heinkel He 111H:
Empty Weight: 17,000lb
Loaded weight: 30,8650lb
Max Bomb Load: 7,165lb
Range: 910 miles with 6,000lb

Heinkel He 177A-5:
Empty Weight: 37,038lb
Loaded weight: 68,343lb
Max Bomb Load: 13,225lb
Range: 1200 miles with 11,000lb

As can be seen from the above the load carrying of the B-17 (any model) is really quite poor. But the built-in survivability, which accounts for miuch of it's loaded weight, was legendary.

The B-24 could carry more, and over a greater distance. One reason why it was the popular choice with Pacific air force generals. But it was a more difficult aircraft to fly than the B-17, especially in formation and did not have quite the same strength to combat damage.

The Halifax could carry a (slightly) larger load than the standard Lancaster, and over a greater distance. But it too was more difficult to fly than it's counterpart, and was more susceptible to damage.

Of all the bombers shown above, only the Lancaster could carry more than it's rated max bomb load. That was the Grand Slam. But that was only in the specially modified B.I's, which were stripped of much equipment to assist in lift. And to it's extremely long bomb bay.

Interestingly the German bombers also had very good lift capabilities, especially the He 111. But at the expense of protective armour and armament. But pound for pound the german bombers could out bomb any equivalent Allied bomber.

Now the B-29.....well that's in a class all by itself. A truly outstanding aircraft. If it had flown over Germany the Luftwaffe, in all probability, would have been as ineffective against it as the Japanese.