Did the 8th Air Force precision bomb or area bomb? (1 Viewer)

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The official US doctrine was 'daylight precision bombing' and the USAAF generally attempted to precision bomb, for a given value of 'precision'. That is, they used mass style attacks from high altitude aimed at single large 'point' targets (marshalling/rail yards, factory complexes, oil refineries, transport hubs ect), with wildly varying degrees of accuracy.

However, the VIII Air Force was willing to blind bomb as well. In fact given N/W European climactic conditions, it would have periodically been rendered ineffective if it had not adopted blind bombing techniques. To their credit, crews often abandoned missions if blind bombing equipment was not working (for example, on 20 March 1944, nearly 70% of bombers failed to bomb after the blind bombing equipment was found to be unservicable).

Precision in WWII was vastly different from modern precision bombing.

An 8th AF combat box ranged from 1200 ft to over 3000 ft wide and could be even longer than this.

The 8th AF improved its CEP from over 3000 ft in 1943 to just under 1000 ft by mid-1944. Medium altitude missions (15,000 ft) had an average CEP of 825 to 1175 ft.

Still, that meant that on average more than 50% of bombs were falling 1000 ft away from their targets.
 
I believe they bombed with radar. There is dispute as to whether the 'target' was the city centre, or industrial sites near the city centre. The commanding officer's report after the bombing states that they were targeting the built up area in the centre of the city. As was so often the case, the language is largely irrelevant; bombs fell everywhere. No-one involved in the planning of the operation could seriously have believed that the end result was going to be anything other than the destruction of Dresden as a city.
 
There was nothing precise about the majority of U.S. level bombing during WWII but that makes a great war slogan.
In 1944 it was precise as the technology of the day. If you're comparing it by todays standards, just turn the page.
 
In 1944 it was precise as the technology of the day. If you're comparing it by todays standards, just turn the page.

It was precise as the technology of the day in that the technology didn't exist. Armaud Amalric had already summed up the nature of this sort of campaign in the Thirteenth century; "Caedite eos. Novit enim Dominus qui sunt eius."
 
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For me, the key question is: given the techniques and technology available at the time, could the USAAF have bombed more precisely? As I see it, the answer is yes, but only at significant cost in operational losses and tempo and only with significant learning from experience.

To increase accuracy, the Eighth could have done the following:

Use larger bombs,
Bombed from lower altitudes,
Bombed in smaller formations,
Increased intervals between bomb groups,
Reduced the width of combat boxes,
Switched to an all B-17 force,
Increased the level of training for crews,
Improved its meteorological forecasting,
Never visually bomb through anything more than four tenths cloud,
Never bomb using blind bombing techniques
Introduce pathfinder aircraft
Reduced/eliminated use of fragmentation bombs

Most of these were figured out during the war by various operational study units, but not all were implemented. Some were ignored completely, or the opposite happened.

Formations got bigger instead of smaller and bomb groups were more tightly bunched for mutual defence, instead of spaced out at intervals to reduce target occlusion. The Eighth increasingly used blind/through cloud bombing through late 1944, which was almost never as accurate as visual bombing. Average bombing heights declined from about 23,000 to about 20,000, but never to the 11,000 to 15,000 ft necessary to produce sub 750 ft CEPs.

The four most significant factors in terms of accuracy were determined to be:
The cloud/visibility conditions above the target. This could affect accuracy by a factor of 10.
The number of bomb groups involved in the raid. A raid of three bomb groups was up to 40% more accurate than a raid of 10 or more groups
The bombing altitude.
The amount of flak over a target. Particularly heavy flak could halve accuracy.


If accuracy is the primary concern, then the best option may be to partially replace/supplement the heavy bomber force with a couple of other types. This could take the form of either long range dive-bombers (single or twin engine) or unescorted fast bombers (two or even four engines).

A dedicated long-range dive bomber in the form of a Ju-88/Tu-2/Pe-2 style aircraft could be used on targets requiring a higher degree of precision or ones that had a reduced level of flak defences. Bombing from lower levels, dive bombers were significantly more vulnerable than heavy bombers, but also significantly more accurate. 30-40 dive bombers with a CEP of 750 ft might put more bombs actually on the target than 200-300 heavy bombers with a CEP of 1200 or 1500 ft

A fast bomber similar to a Mosquito, or even an enlarged, four-engine Mosquito. In daylight Mosquitoes were consistently capable of CEPs of 390-450 ft when bombing from under 6000 ft in gentle dives. Average CEP for low level bombing was about 660 ft. This might be the solution needed for relatively high-precision targets with higher levels of defence.

So, I think the USAAF could have pursued a hi-medium-low approach: Use escorted heavy bombers during clear conditions over Europe for the largest of target, use dive bombers for 'precision' smaller targets with lighter defences, use fast/low level bombers for 'precision' heavily defended targets.
 
How precise can a formation that is almost 1600ft wide be? (Jan 1944) In Feb 1945, the width was reduced to ~1200ft wide.
 
If it were possible, accurate bombing would no doubt be preferable. Why put ordinance on marginal targets?

However, it appears rather evident that the strategy changed as the poor accuracy was recognized as yielding unacceptable results. Incendiary bombing isn't just a harrassment tactic. It's a marked and very effective change in the theory of bombing. Rather than relying on the energy of the bomb, incendiary bombing utilized the energy in structures and material on the ground at the target. This allowed orders of magnitude more destructive energy to be visited on the general area of the target. By the time Japan became the target, large cities were routinely destroyed by firestorm. A few cities had to be reserved from such attack so there would be appropriate targets for the nuclear bombs.
 
We have all heard the claim to be able to put a bomb in a pickle barrel, but what was the real CEP of the Norden sight, and surely the type of ordinance dropped would have a considerable effect on accuracy?
 
However, the VIII Air Force was willing to blind bomb as well.

Blind bombing and area bombing are NOT the same thing.

All Air Forces did both. The US 9th Air Force rummaged through its photo files to illustrate the difference in its own official history.


pre_area_9th.jpg




Cheers

Steve
 
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I never read about precision bombing by the 8thAF,
just like Jabberwocky i can't see how it could be doable by rather large formations and using mass produced bombs (notperfect aerodynamicaly).

But it was achieved in WW2, but not by the USAAF, but by the RAF with the 617sq. That sqn was the only (to my knowledge) to be able to hit targets with very great precision (using technical capabilities of WW2), but they also used specially handcrafted bombs for this use (the 6 and 10tons earthquake bombs).
 
I suppose Hiroshima and Nagasaki were technically precision bombings as both bombs hit the targets!
 
But it was achieved in WW2, but not by the USAAF, but by the RAF with the 617sq. That sqn was the only (to my knowledge) to be able to hit targets with very great precision (using technical capabilities of WW2), but they also used specially handcrafted bombs for this use (the 6 and 10tons earthquake bombs).

617 and 9 Squadrons were the RAF's premier "precision bombing" units. They did not use the standard Mk XIV bombsight but the superior SABS MkIIa sight. In early 1945 617 Squadron was achieving an average radial error of a mere 125 yards from 20,000 ft which is as precise as anybody ever got. Two other precision squadrons (can't remember the numbers) were formed, but using the Mk XIV sight the best they achieved was an average radial error of 195 yards.

Cheers

Steve
 
Blind bombing and area bombing are NOT the same thing.

Correct, and I did not say that they were.

However, blind bombing was an order of magnitude less accurate than visual bombing and this was never corrected, even with heavy training in the US of Oboe, Gee and H2X. USAAF studies at the beginning of 1944 showed that only 5% of bombs dropped in 10/10ths cloud using blind bombing techniques fell within a mile (5280 feet) of the target. By December 1944, this figure was 5.6%.

To quote Lt Col Raymond H. Willcocks' essay, 'The Ethics of Bombing Dresden'

"As the war in Europe ended, the American method of bombing had moved away from its established strategy of precision daylight bombardment. It began to merge with the RAF strategy. This merger enabled the USAAF to assist in the land battle with Germany by directly supporting the field commander in striking targets anytime, day or night. The USAAF had begun using "blind bombing" guided by the H2X radar, the American version of the British H2S system. By the war's end, 80 percent of all of the 8th AF missions utilized this technique."
 
617 and 9 Squadrons were the RAF's premier "precision bombing" units. They did not use the standard Mk XIV bombsight but the superior SABS MkIIa sight. In early 1945 617 Squadron was achieving an average radial error of a mere 125 yards from 20,000 ft which is as precise as anybody ever got. Two other precision squadrons (can't remember the numbers) were formed, but using the Mk XIV sight the best they achieved was an average radial error of 195 yards.

Cheers

Steve

I thought 617 squadron was the only user of the SABS during wartime and 9 sqn used the standard Mk XIV
 
I think that the 8th Air Force had specially trained, selected units, analogous to the RAF's 617 Squadron, that could precision bomb, but there was no attempt to do so in the massed raids.
 
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Dive bomb and drop the whole payload, sure, you'll lose a wing mid-dive, but it'll look bad*** up until that point.
 
Let's get real. How could you "precision bomb" in a B-17?

Short answer is...you can't. I suspect part of the problem is a mis-match of aircraft capability to actual need which had its origins in the 1930s perception that "the bomber will always get through" coupled with Billy Mitchell's claims about precision attack of naval vessels. As late as 1941, the US Government believed in the "strategic deterrent" of the B-17 as demonstrated by the reinforcement of the Philippines that year in a failed attempt to cow Japan into limiting Tokyo's imperial aspirations. Japan had been using "heavy" bombers in China for years and was not intimidated.

When war came to America in December 1941, it was found that the B-17 was not the impregnable airborne battleship that pre-war planners seemed to perceive it as, indeed its early war operations were rather unsuccessful. Some of this revisionist understanding came from the RAF's usage of the B-17 which clearly showed that the bomber didn't always get through. The B-24 had some better features than the B-17, not least of which was a better bomb load, but it was harder to fly and there is anecdotal evidence that it was less resistant to combat damage than its Boeing stablemate. There was undoubtedly continued belief in the Norden bombsight as the ultimate extension of Billy Mitchell's belief in precision bombing but sufficient bombs had to be delivered on the target in a hostile environment, something that Mitchell's demonstrations never replicated.

It should also be observed that interwar expectations of the efficacy of "heavy" bombing were woefully over-optimistic. By early 1942, it was pretty clear that the B-17 didn't deliver sufficient explosive force at long ranges. Pre-war beliefs that small numbers of bombers (small by comparison with the 1000-bomber raids of 1944) carrying 2000lb of bombs each would paralyse a city proved to be totally inaccurate.

Fortunately for the USAAC, the solution to both the lack of delivered explosive force and the bomber not getting through to the target was the same - send over a large number of bombers flying together in formation to provide weight of bombs and mutually-supportive defensive firepower (although it took time to get that right, with different formations and considerable up-arming of defensive firepower in individual bombers). Of course the problem is that precision/accuracy pretty much disappears with the the large-formation approach.

Early 1940s technology could have implemented precision bombing more effectively, either using long-range dive bombers or by adopting the early Mosquito tactic of going in fast at low level. Neither approach was a silver bullet, though, and losses - particularly for the dive bombers - would have been high. There remain questions about whether the high-speed, unarmed "Mosquito approach" could have worked on the scale required for a sustained strategic bombing campaign - it would be great for taking out key components within a target system (eg hit the switching controls rather than plastering the entire railyard) but such targets are relatively easy to repair.

What is clear, though, is that the USAAF was saddled with the B-17/B-24 and Norden bombsight which, frankly, were not up to the expectations set for precision bombing even at that timeframe, and particularly not in the European theatre. It could be argued that the bomb load of the B-17 wasn't really sufficient for a strategic air campaign in 1942...although that's a drift from the main thrust of this thread. The B-17/B-24 + Norden combination did the job because they had to - it would take too long to overhaul doctrine, equipment and training to start a strategic bombing campaign commencing in early 1942.
 
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Let's get real. How could you "precision bomb" in a B-17?

The same way 617 Squadron did it from a Lancaster. It could be done, but it was far from routine practice and, I suspect, very few heavy bomber units had the capability.

As an aside, I've read (I cannot remember where) that, until the adoption of electronic aids to navigation (especially, iirc, radar), navigational errors made any claim of precision bombing total pretense: when you navigate to the wrong city, it doesn't matter if your bombsight can give you a CEP of 10 m. (as a second aside, I've read that the CEP for the 8th AF's heavy bombers was about a quarter mile, or 400 m).
 

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