Crazy optimism: daylight bombing in WWII

Miscellaneous and Personal Stuff I Must Share
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As everyone knows, the US entered WWII figuring its bombers could drop bombs civilizedly, just destroying military targets, as long as they flew in daylight. So that became the plan.

It seems Norden’s president had said in 1940 “We do not regard a 15-foot square … as being a very difficult target [for the Norden bombsight] to hit from an altitude of 30,000 feet.” Obvious question: why didn’t air force planners require a demonstration of such a wacko claim? A bunch of demonstrations would seem worthwhile, and no doubt would have made it clear that Norden’s president had gone round the bend. Instead, planners apparently decided to hope there was a shred of truth in the story. Guess the problem was the Norden sight was thought to be such a war-winning secret – maybe they worried that word of a real test would leak out.

(Next question: 1940-era US bombers were supposed to be able hit ships at sea. Did they imagine the Norden sight could hit moving targets?)

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For context, and with at least some answers to the o.p.'s question:

Stranger

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Former aerial bomb dropper here.

From the POV of an airplane, the ground is a moving target. A ship is no different. The distinction comes in that a ship may be a maneuvering target.

A ship that’s steaming along at steady course and speed is no harder to hit than the same ship tied to a pier. If the ship is turning or changing speed, now that’s a whole different and much more difficult matter. One that really can’t be overcome by unguided bombs of the sort a Norden was useful for.

There was a lot of unwarranted optimism about the Norden.

But a lot of the crappy results were due to crappy bombs which had poor manufacturing tolerances and QC. Fins on crooked, bent, heavier or lighter, etc. With the result that even aimed perfectly and falling in benign conditions, what should have been a nice neat “stick” of a dozen bombs landing in a straight line at 50m intervals turned into a raggedy salvo spread randomly around a 400m square. Which given the low explosive and shrapnel power of those bombs made them real ineffective against anything that wasn’t a) huge and b) flimsy.

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I’m unsure, if even you arranged to have a bomber drop several bombs from external hardpoints at the precise same moment, whether random turbulence would spread them out far beyond a five-meter square. IOW, if even a perfect bombsight could never produce high accuracy.

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The Army Air Force really wanted high level bombing of ships to be viable (get more money in their budget instead of the Navy getting it) and made some claims about its effectiveness but it was woefully ineffectual. Hitting whole factories that were MUCH bigger than a ship and not maneuvering was a challenge. Part of the reason for massive aerial formations carpet bombing something. A few bombs were likely to hit the target just by sheer numbers and some luck (compared to today where a handful of jets can put the bombs mostly wherever they want and achieve what took a hundred bombers in WWII).

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It should be pointed out that the US military - like other militaries of the time - wasn’t as accuracy-prioritized focused on hitting military targets as it is today. Sure, they wanted the military targets struck, but they were bombing civilians too just for the sake of it (civilians were considered totally fair game) and if a bomb missed its intended target and hit a residential area, that was still “good,” just not as good as hitting the intended target itself. In other words, a bit of error in the Norden bombsight was more acceptable back then than today.

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It wasn’t “just for the sake of it.” Total War suggests the whole population (mostly) is involved in the war effort in one way or another. The entire populace is lending its efforts to support the war.

So, killing a farmer means less food for the army. Killing a factory worker means one less person to build a weapon. Killing a clerk means one less person to keep track of all the goings-on (which doesn’t sound very important but is). Not to mention children who may soon be conscripted to fight. (and so on)

It’s awful but was it ever done because they just figured why not? May as well kill all of them.

Contrast that with Desert Storm. The whole US was not involved in the war. Nor was all of Iraq. So, there was no wholesale bombing of civilians (but of course, there was a lot of collateral damage to them…probably unavoidable).

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I would argue that hitting military targets was entirely the original point of strategic bombing in the larger doctrinal sense espoused by Douhet, Mitchell, et al. They conceived of aerial bombing as practically being able to teleport ordnance to its target via a higher dimension– which in a sense it was given that war had been two-dimensional since time immemorial until World War One. Given the apparent futility and the paralyzing fear of trying to fight a ground war against the modern power of “fire” in the military sense of the word, strategic bombing was thought to be the only viable method of war left. Recall also that this doctrine was formulated before the advent of radar, when it was presumed that lack of warning would make opposing an aerial attack virtually impossible. Strategic bombing pre-WW2 would have had no backers if it couldn’t claim to produce war-winning results.

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Radio controlled anti-ship weapons were developed in WW-II. Combined with the advent of airborne radar it was a major shift in the war. It forced the Nazis to withdraw their submarines because of limited ability to defend themselves.

As for the Norden bomb sight it was a sophisticated instrument. It depended on accurate wind information which varies greatly between altitudes. Something that the bombardier has no way of knowing so the accuracy is degraded on gusty/windy days

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Years ago I read David Brinkley’s memoirs. Because he could type, he was pulled out of the front lines where his fellow North Carolinians were sent. That was right before Operation Cobra, where precision aerial bombing would replace artillery in preparation for a ground assault. The North Carolinians were wiped out by the imprecision.

Compared to Paul Fussell’s memoirs, where he came upon a circle of Germans, mostly boys, dead as rocks but not a mark on them. They’d received a “time on target” barrage where several American batteries coordinated simultaneous air-blasts directly above them.

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Possibly the most accurate high-altitude bomb strike in WWII: the 10-foot wide Yellow River Bridge hit from 14,000 ft by a bomber from the 308th Bomber Group

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Out of how many bombs dropped?

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All I know is what it says in the article (it was also documented in Martin Caidin’s book Air Force:A Pictorial History of American Airpower)

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I certainly do not know but occasionally someone will get lucky.

Ask them to repeat that 10 more times and I’d bet all ten would miss.

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Hitler feared the successful bombing of war production factories so much that he went on a massive attempt to build underground factories. Too big a job too late in the war. The facility to launch V2 rockets (on a scheduled basis) was built in an impenetrable facility. The biggest bombs in the war bounced off it. So the British bombed around the facility and collapsed the structure.

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Yeah, they discovered that “earthquake” bombs did as much or more damage simply by shocking the foundations of facilities as hitting them directly. Fun fact: the USA even worked on its own 40,000 lb (!) version before they were made obsolete by atomic bombs.

Although: I’ve wondered if something like that would have been an effective weapon in Vietnam against underground insurgent bases; especially given how well penetration bombs would have worked in the soft ground there. Add the at-the-time newly developed laser guidance package and someone on the ground to paint the target with a laser, and such a bomb would have collapsed every underground tunnel and bunker within 100 yards of the impact point.

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From what I’ve read, the Norden bombsights were indeed extremely accurate for their day, IF conditions were just right. That includes weather, wind, speed, bombardier skill, everything adjusted just-so from the sight itself, to the bomb racks, altitude indicators, airspeed indicators, bomb manufacturing accuracy, and everything else involved (the Norden actually took over piloting the plane and releasing the bombs).

But all of that was rarely the case in wartime conditions. More importantly, the tactics of the era weren’t really conducive to each bomber sighting the factory and releasing their bombs when their particular bombsight and bombardier did their job. Instead, the realities of anti-fighter defense and issues with accuracy meant that they eventually just ended up with the lead bomber for each group (four squadrons, 48 aircraft) having a bombsight, and the rest kept formation and dropped their bombs when the lead bomber dropped theirs.

Of course, this doesn’t do much for pinpoint accuracy, but it worked well enough for destroying factories and industrial targets like railroad yards. Often the problem was that those targets were in the middle of built up areas, and collateral damage was inevitable.

Combat accuracy was possible- read about the Marienburg raid of 9 October 1943 where 96 B-17s dropped about 218 tons of bombs on the Focke-Wulf plant, putting something like 83% within a 2000 foot radius of the aiming point, which was phenomenal accuracy for the time.

9 October 1943 | This Day in Aviation

But that was accomplished in nearly ideal conditions with little to no opposition. Other raids weren’t nearly so accurate, due to weather like clouds, wind, etc…, enemy opposition/evasive maneuvers, extremely high altitudes, and general slop in the process.

However, even at their most inaccurate, the US bombers were at least trying to hit specific targets, unlike the British who just basically indiscriminately carpet bombed entire cities at night.

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There are few things that can better illustrate that the phrase, “military intelligence”, is an oxymoron. The war had been going on for years before we entered it, so it seems inconceivable that our military leaders didn’t understand the strength of the German defenses in general and the Luftwaffe in particular. But, there you have it.

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B-25s at low level could skip bomb Japanese ships. Like skipping stones on a lake. B-25s also did massive damage with a dozen .50 caliber machine guns facing forward.

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Implicit in this whole discussion, but so far unmentioned, is that all unguided bombing accuracies get better the closer the bomber is to the target. Much better.

Skip bombing from 100 feet above the water at a range of ~1/4 mile while aiming at the broad side of a ship with significant height is almost a can’t miss situation. Ditto strafing such a ship.

OTOH, B-17 or B-24 drops onto factories, bridges. or [whatever] from 5 or 6 miles straight up are utterly different problems. Especially on partly cloudy days.

The computing bombsights on modern fighters make it pretty straightforward for a single aircraft to reliably drop unguided bombs (singles, pairs, or groups up to about 6) within 5 or 10 meters of the desired aimpoint. From a slant range of anywhere from roughly 0.5 to 3 miles. Once again, getting up close and personal with the work really helps. Which gets a lot harder the more the enemy near that target are able to shoot back.

The nature of the massed bomber raids was that e.g. 96 B-17s would have a roughly triangular footprint in the sky about a 2500 across. Even if the bombs fell perfectly uniformly, the impact pattern would be the same size and shape, but smeared in the direction of flight by anything from 500 to 1000 feet depending on how quickly the train of bombs from each aircraft was programmed to drop.

At ~8 500# bombs per airplane you’re looking at about 750 bombs dropped across an area of about 1/2 x 3/4 mile. It’s a shotgun with a barrel 1/2 mile in diameter. And it’s “aimed” at a spot on the ground 1/2 mile in diameter too. It isn’t a rifle.

That’s an area of about 11 million square feet. Divided by 750 bombs is one bomb per 14,000 square feet. If spread evenly around the area, each impact would each be about 120 feet from their neighbors. It’d be scary as hell to be sitting in the middle of that, and many exposed people or soft vehicles and buildings would be heavily damaged or destroyed. But it would not be death to all and destruction to everything.