"How did U.S. precision bombing work?" Topic

So imagine fifty or a hundred B17 bombers, their mission to destroy a ball bearing factory. Assuming the lead bomber is right over the factory (allowing for speed, wind etc) and drops its bombs. It may be followed by some of the others in a line behind it over the target but they couldn't all be in a long queue above the factory or they'd be too vulnerable to flak. I presume most planes will be spread out to its left or right, so how did all those other planes hit the target?

They didn't! By bombing a pattern centred around the aim point the spread of bombs was intended to offset any inaccuracy in the bombing.

Too much has been made of the vaunted Norden bombsight, even the atomic bombs drifted off target!
'Iron bombs' are, by their very nature, inaccurate, area effect weapons.

Much was propaganda, though in a plane with very good conditions and no one shooting at you the Norden sight was better than anything else. Once you had hundreds of aircraft on 1 target it probably could be compaired to a 1812 musketeer battalion shooting.

It didnt.

I wonder what Romanian, Italian, German, and Japanese sources have to say about the efficacy of U.S. precision bombing?

There are bomb damage assessment reports that were made for every mission. They fill books and have very nice diagrams of where every bomb hit on the intended target. They had a set in the library at the Combine Arms Development Center at Ft. Leavenworth. I looked thru some of them while I was attending a course there.

Yea, frequently the whole formation would drop on the lead bombardier's cue, and hope for the best as far as target saturation and accuracy.

Now, if you want to really discuss "precision bombing" in WWII, look no further than US skip-bombing against the Japanese in the Pacific theater.

Lots of great low level attack on vessels at wave-top height, with superb success against them.

Dive bombing was also very accurate, probably more accurate than level bombing or artillery fire. It just put huge stresses on the airplane (thinking Stukas) and the crew. Dive bombers were also vulnerable on the pull-out after releasing.

It should also be noted that all nations suffered from 'creep back' in mass bombing, especially when Flak was being fired at them.

The way it worked was this. The lead or master bomber (by day) or the marker flares (by night) would go down and the first bombs MIGHT be near this target. As the bomber stream flies in there is a natural tendency among crews to want to 'let go' early as this means they can increase speed or turn/evade the Flak firing at them – which they cannot do while on the bombing run itself, it would spoil their aim.

This tendency will mean that the bombs now dropping will strike earlier and earlier, further and further short of the target, as each aircraft drops a little earlier at where they can see the previous bombs are currently landing. The RAF, at night, had a system of re-marking with other flare colours and a master bomber might orbit the area with new flares on board and re-mark the target to try to prevent creep back. He might also broadcast on the radio to 'bomb on the red' or 'bomb on the yellow' as the new flares ignited. The subsequent use of radio navigation aids and centimetric radar made this somewhat less of a problem, especially if the radar gave a clear picture of the target area through the smoke and dust. Aircraft could eventually bomb blind at the end of WW2, through cloud, using such aids and thus largely eliminate creep back.

Creep back led to the disaster on the first day of Operation Cobra, the US army's attempt to blow a hole through the German lines in Normandy. The advisable way that it should have been done was to bomb ALONG the German lines so that any creep back (then already a known phenomenon) would simply kill other Germans to the right of the US attack. However the USAAF argued that this flight path would put them over a Flak zone and thus the decision was made to bomb from the US side of the lines towards the Germans. The result was an inevitable creep back and heavy losses among US ground troops including the only four-star general to be killed in combat. Cobra was effectively stalled as the head was blown off of the attack.

US casualties were 111 killed and 490 wounded.
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RAF blind bombing aids:
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Barry

The USAAF changed the bombardier's title to 'toggaleer' [who was typically a sergeant] later in their bombing campaign.

They just gave up on any pretense of accuracy and resorted to area bombing. It still figured in the propaganda.