WW 2 Bombing Accuracy (or not)

[Wander00]

Just watching an episode of Blitz Cities and fell to wondering about the comparative accuracy of British and German bombing raids. The Butt report demonstrated the inaccuracy of Bomber Command in the early part of the War. Were the Germans any more accurate?

[Phoenix1969]

Hahahaha - think you should have a look at the 'accracy' (or not) of your speling :D

[Stanwell]

Wander00,
I tend to think that, in the early stages, the 'shock and awe' aspect of it was more important.
Yes, we did waste quite a bit of 'cast iron and gunpowder' and I'll be interested to hear if there are any figures for comparison.

[Wander00]

Well, good word to type wrongly. Cannot change it, but maybe Mods can, please.
Now , back to the topic..................



Done
Senior Pilot

[Chairborne 09.00hrs]

Many of the towns involved were not too far from the sea or major water features, which meant they were easier to find. The Luftwaffe also used pathfinder units (KG100) and had some electronic aids. They did an effective job, but only had a modest bombload.

[CNH]

They were accurate enough at Coventry.

[brokenlink]

Wander, I'll check with the PFF museum at Wyton and get back to you. From memory the error was at times in the high tens of miles.

[jensdad]

They even got the wrong country on at least one occasion: The town of Schaffhausen in Switzerland was mistakenly bombed by either the USAAF or RAF.

[FlightlessParrot]

Just watching and episode of Blitz Cities and fell to wondering about the comparative accuracy of British and German bombing raids. The Butt report demonstrated the inaccuracy of Bomber Command in the early part of the War. Were the Germans any more accurate?
German accuracy was much higher, due to the use of beam guidance systems and pathfinder units. Google "Battle of the Beams" for an intro to a plethora of information (other search engines are available).

[PPRuNeUser0139]

This programme (https://www.youtube.com/watch?v=Uf5caj9ZhpQ) explains the story of the early German successes with radio navaids such as Knickebein, X Gerat and Y Gerat:
"Gee" - the RAF's first radio navaid - entered service in 1942. More here (http://www.raf.mod.uk/rafcms/mediafiles/EEA1B9D1_5056_A318_A88B16BD35A68C31.pdf) on the history of navigation in the RAF.

[India Four Two]

For anyone interested in this subject, "Most Secret War", RV Jones' autobiography, is a must read.

[philbky]

Depends on what is meant by accuracy. If talking about hitting a particular area then the accuracy was greater than hitting a given specific building or group of buildings etc. The German guidance systems were initially in advance of anything Britain had. By 1942 British methods were in the ascendency due mainly to the decision to take the bombing campaign to the German industrial heartland and the determination of "Bomber" Harris at a time when German raids on Britain had passed their peak.

Both sides had times where targets were missed, sometimes with a large margin of error. The Luftwaffe bombing of Dublin when Liverpool was the target springs to mind and both sides had methods of misleading raiders into dropping bombs on empty countryside.

To effectively hit a small, defined, target took a great deal of training and not a small amount of luck. That is why area bombing was carried out by both sides. The British raids on the dams, Amiens prison, the Tirpitz and the u-boat pens at St Nazaire, where tightly defined targets and aim points were specified, took far more specialised training than that given to crews on the regular bombing sorties over towns and cities.

Later in the war the Allies found that smaller aircraft in small numbers, such as fighter bombers, were effective in destroying specific items such as trains, bridges and less well defended buildings without the need to area bomb with large numbers of heavy bombers and this use became an important tool in the run up to and after D-day.

[PAXboy]

There are many reports of both sides 'ditching' their bombs. Only last month I read a first hand report of an 'attack' on a Fleet Air Arm base in Scotland where the the bomber ditched the bombs in the sea. Since it was a clear night and the observers could see the aircraft and the target was very close to the coast - the crew decided not to attack, for whatever reason.

Later in the war, the RAF crews had to take a photograph to show that they were over the target in order to qualify for the trip against their Tour. Whilst many failed to find the target, for many understandabale reasons, some crews deliberately chose not to bomb the target.

[emeritus]

I unfortunately can't remember where I read it,but many many years ago I read that the RAF had done research into bombing accuracy during WW2 and concluded that only 1 bomb in 16 had fallen within 1 mile of its target.

Am interested to see if anyone can elaborate on the subject.

Emeritus.

[Rossian]

.....were not all that great. John Cruickshank VC once told me that he had been tasked into a "box" SE of Iceland for a very long surveillance mission in his Catalina. The cloud base was was low and very thick. No sun, no stars when it got dark, all done on DR when the forecasts were a tad "variable". At off task time they set heading for Sullom Voe in Shetland and after a long transit made landfall on the island of Benbecula. Buggah!! It was now another 4 hrs coast crawling to back to SV. And errors of that magnitude were not uncommon.

This tale was triggered after his first trip in a Nimrod where, back in dispersal the baby nav was claiming that the nav system was a tad out - the error being inside the wingspan of the aircraft after 6 hours.

The Ancient Mariner

[Innominate]

Emeritus

You're thinking of the Butt Report https://en.wikipedia.org/wiki/Butt_Report mentioned in the original post. There's a transcript at https://etherwave.files.wordpress.com/2015/02/butt-report-transcription-tna-pro-air-14-1218.pdf

[Wander00]

Emeritus - as I understand it, that was the Butt Report that started the attempts to improve bombing accuracy

[binbrook]

Are we talking about accuracy or effectiveness? Accuracy is irrelevant if you can't find the aiming point and the woeful results early in WW2 are surely down to the inability to find the target town, never mind the aiming point. Someone out there should be able to quote the sort of CEPs being achieved on the range at the time, but in 1946 IX(B) with its new Lincolns was proud to record an average error (not CEP) of 32 yards for 8 bombs from 20000 feet - step forward F/O Myatt and crew! I suspect 300 yards was nearer the mark in real life.

Navigation without radio aids is/was not easy and AFAIR in the 50s a requirement for classification as a Select Canberra crew was to keep within 50nm of track on astro.

[leesaranda]

The Butt Report, 1941, found that on average only one in three RAF bombers claimed to have reached the target and, of these, only one in five bombed within 5 miles of it, a figure that fell to one in 15 on a moonless night.
So only 1 bomb in 45 got within 5 miles of its target under those conditions.

The Operations Research Group were given the task of identifying the problems, and providing solutions.

ORG calculated, from ‘real world’ photographic data, that the Dead Reckoning 50% Band of Error would have been 24 miles radius after the 3 hour flight to Berlin.

DR Errors on a UK to Berlin flight:

A 1o error in heading gives an across track error of 10 nautical miles.
A 10 knot error in the across-track component of wind gives an across track error of 10 nautical miles.
A 10 knot error in the along-track component of wind gives an along- track error of 30 nautical miles.
A 1 minute error in bomb release gives a 3 nautical mile along- track error.
A pencil line is ¼ mile wide on a 1:500,000 plotting chart.

[Load Toad]

There was also problems with bomb aiming and even the bomb bar doors of early war aircraft were held shut with bungee cords - so there was a delay whilst the falling bombs actually opened the doors.

[Stanwell]

I hadn't been aware of the Butt Report.
Was Lance-Corporal Jones privy to that?
I mean, he'd observed that "They don't like it up 'em".

[emeritus]

Innovate and WanderOO....

Thanks for the heads up on that. I'm sure the info I read was in regard to the whole war.
The Butt Report was dated 08/1941 hence the figures were even worse as one would expect as Bomber Command were still getting their act together.

Shall nevertheless digest it more fully as time permits.

Emeritus

[Danny42C]

Think I once referred to this on "Pilot's Brevet" as a city being: "the smallest thing a navigator could find that was too big for the bomb-aimer to miss".

Really, it was a miracle that the heroes of Bomber Command (and I use the word advisedly, having never been one) could even find a city, after 3-4 hours over a blacked-out continent with little but DR to help them, while dodging flak and being hunted by night fighters.

Remember Johnson: "Sir, the wonder is not that the bear dances well, but that he dances at all".

Before the advent of modern, laser-guided weapons, "Precision Bombing" was a myth; the nearest thing to it was a dive-bomber (advt). Look up "Midway", where three big Japanese fleet carriers (out of a battle group of four) were left blazing - in a matter of minutes!

Danny42C.

[Stanwell]

In other news...
Flour-bombing from a Tiger Moth at small Club Days is now not permitted - because 'somebody might get hurt'.

[megan]

Accuracy after the Pathfinders entered the scene.By the start of 1944 the bulk of Bomber Command was now bombing within 3 miles of the PFF indicatorsRAF Wyton - The Pathfinder Force (http://www.raf.mod.uk/rafbramptonwyton/history/thepathfinderforce.cfm)

[FlightlessParrot]

Accuracy was possible early in WW II, but mostly at too high a cost.

It seems that in the 1930s, everyone overestimated the effectiveness of bombing, and underestimated the vulnerability of bombers in daylight. The two factors compounded, so that a loss-rate that would be acceptable for a "knock-out blow" was disastrous for a long campaign. Baldwin is always scorned for saying that "the bomber will always get through," but two things need to be said. First, he was relying on the advice of his professional advisers in the RAF, which is what a politician is supposed to do; second, he (and they) were right, some bombers always did get through, but the losses were unacceptable. I think Bomber Command regarded 3% losses as tolerable, but 10% was a defeat.

It is notable that the Germans, who discarded the notion of strategic bombing (that is, counter-city actions), were the only force that early in the war had the means to undertake it, with a doctrine of fighter defence of bomber forces (though the practice was flawed, under the stress of losses), and adequate guidance systems for accurate bombing at night.

Precision bombing always involved heavy losses. Once the Ju 87 met serious fighter opposition, it became very expensive to operate, and dive-bombers always seem to have been vulnerable: it is claimed that even at Midway, the greatest success of precision dive bombing, the sacrificial diversion of the torpedo bombers was crucial in getting the dive bombers through in sufficient numbers to score the very small number of hits that decided the battle.

As for the original question, the Germans clearly had better accuracy early in the war, with dive bombing for tactical warfare, and guidance systems for night bombing which enabled strategic attacks to be effective. The USA had dive bombers also in its Navy, and a strategic bombing force that could be accurate in clear skies in daylight, but which could not defend itself as expected, and which had problems with clouds. Even late in the war, when British accuracy had improved greatly, it took a lot of sorties to disable Tirpitz.


The vision or nightmare of the 1930s only really came to reality with the development of nuclear weapons, which made accuracy less important (though even then, apparently, Nagasaki was spared some destruction because of an error in aiming).

[wiggy]

Nagasaki was spared some destruction because of an error in aiming

TBH I'm not sure if the crew were ever able to see the planned AP at Nagasaki, so didn't "bomb" on it. I'll have to check my sources (later) but I know there were problems with significant cloud cover ("undercast") and I think there was even discussion of making the drop by radar.

Edit to add: From Rhodes, "Making of the Atomic Bomb", I paraphrase: Original AP covered in cloud, radar bombing considered. On run in for a radar drop hole on undercast allowed sighting/drop on a known feature (a stadium) "several miles upriver from the original aiming point".

FWIW Rhodes does indeed comment that destruction was reduced due to terrain surrounding the eventual ground zero, but in the context of this thread I'm not sure that can be claimed as down to an "aiming error".

(Apologies if I'm being overly picky).

[RedhillPhil]

Accuracy after the Pathfinders entered the scene.RAF Wyton - The Pathfinder Force (http://www.raf.mod.uk/rafbramptonwyton/history/thepathfinderforce.cfm)



Didn't the introduction of the SABS bombsight make things more accurate?

[FlightlessParrot]

Wiggy
I don't think you're being over-picky, and I'm not wanting to quibble for the sake of quibbling. Evidently they hit more or less what they were aiming at; but in the overall picture of accuracy in strategic bombing, it also counts that they did not hit the intended aiming point. Even with the advantage of complete command of the day-time air, still the same kind of problem, though to a much lesser extent, of earlier bombing in Europe, namely of getting over the right location in the first place.

It is interesting that they did not rely on radar; do you have any information on why not? I've read somewhere the judgement that USAAF bombing on radar through cloud in Europe amounted, pretty much, to adopting area bombing, and so was a step towards the wholesale counter-city bombing of the Japanese campaign.

I'm at a loss whether modern accuracy makes things better or worse for the poor souls beneath it.

[ian16th]

It is interesting that they did not rely on radar; do you have any information on why not? Using the H2S radar gave out transmissions that the enemy fighters could home onto.

This has always been a shortcoming with any airborne primary radar system.

The secondary radars such as Oboe and Gee did not suffer from this problem, but they did have the shortcoming of needing ground transmitters within range of the intended target.

[Pontius Navigator]

Are we talking about accuracy or effectiveness? Accuracy is irrelevant if you can't find the aiming point and the woeful results early in WW2 are surely down to the inability to find the target town, never mind the aiming point. Someone out there should be able to quote the sort of CEPs being achieved on the range at the time, but in 1946 IX(B) with its new Lincolns was proud to record an average error (not CEP) of 32 yards for 8 bombs from 20000 feet - step forward F/O Myatt and crew! I suspect 300 yards was nearer the mark in real life.

Navigation without radio aids is/was not easy and AFAIR in the 50s a requirement for classification as a Select Canberra crew was to keep within 50nm of track on astro.
The accuracy you talk of here is academic bombing with the aircraft having conducted a wind finding over the target followed by cloverleaf attacks.

For live bombing Research Branch observed that there was a tendency for crews to drop bombs early on the markers with subsequent aircraft dropping early on prior bomb bursts.

With the PFF the 35 Sqn 540 stated accuracy of marking as 400 yards.

Later ResBat calculated that combat degradation was in the order of 75% over training attacks.

[DC10RealMan]

In one of the raids in the Summer of 1943 RAF Bomber Command was tasked with destroying the Krupp armaments factory in Essen.

RAF Pathfinding Mosquitoes utilizing the Oboe blind bombing device laying flares to indicate the factory which was totally destroyed, so accurate was the attack that the Nazis looked for the traitors (Communists, of course) who had lit up the factory target for the RAF as they couldn't comprehend such accuracy.

The high flying Mosquitoes which would routinely fly at 30,000ft could use the blind bombing aid codenamed Oboe based on two transmitter sites in Kent and Suffolk and which was limited due to the curvature of the earth hence the use of Mosquitoes which would increase the target range.

The Peenemunde Raid of 1943 used a visual timed run-in from the island of Rugen with the deliberate task of killing the German scientists who were developing the V1 and V2 rockets, the most famous casualty was Ing Dr Thiel who was a propulsion specialist.

By 1943 RAF Pathfinder Force employed a range of tactics to use subject to the weather with code names such a Newhaven, Parramatta (The birthplace of AVM Don Bennett) and Wanganui which is worth another chapter in itself!

[Pontius Navigator]

A word about high level bombing accuracy - wind.

There is an assumption that the bomb spends more time at height and stronger winds than at lower levels. Based on that the wind used on a computer is factored at about 2/3 that of the wind at height. This holds good where the air mass is homogeneous. If dropping through a frontal zone with wind sheer the bombs can fly practically anywhere.

[FlightlessParrot]

A word about high level bombing accuracy - wind.

There is an assumption that the bomb spends more time at height and stronger winds than at lower levels. Based on that the wind used on a computer is factored at about 2/3 that of the wind at height. This holds good where the air mass is homogeneous. If dropping through a frontal zone with wind sheer the bombs can fly practically anywhere.
Thank you. Which means that, however good the navigation aids, however complete the command of the air, however accurate the bomb sights, there's an irreducible potential for inaccuracy in high-level bombing without in-flight guidance.

I've not seen that pointed out so clearly before, and I have read a fair bit.

[ICT_SLB]

Flightless Parrot,
It was not an estimate from the 30s but the actual civilian losses from the German bombing campaign in WWI that gave cause for alarm. The Gothas and R Planes actually inflicted higher casualty rates than in the later Blitz.

[Pontius Navigator]

Thank you. Which means that, however good the navigation aids, however complete the command of the air, however accurate the bomb sights, there's an irreducible potential for inaccuracy in high-level bombing without in-flight guidance.

I've not seen that pointed out so clearly before, and I have read a fair bit.
Exactly. Given a time of bomb fall from 20,000 feet of 40 seconds and a difference in wind speed assumption of only 18 kts we have an error on the ground of 400 yards.

The error can be minimised by dropping parallel to the wind direction and dropping a stick of bombs. Ideally you would fly downwind to minimise tome over target. In training we would fly in to wind to maximise time for target identification and aiming.

As you can see, dumb bombing is a function of compromise and luck.

PS, even at 500 feet and TBF of 6 seconds there is plenty of scope for getting it wrong. That is level bombing of course, the TBF for dive bombing will be less.

[FlightlessParrot]

Flightless Parrot,
It was not an estimate from the 30s but the actual civilian losses from the German bombing campaign in WWI that gave cause for alarm. The Gothas and R Planes actually inflicted higher casualty rates than in the later Blitz.
Yes indeed, but these were on a relatively small scale, and the element of estimation came in scaling them up for the future war. It would be interested to find out how much estimates of bombing casualties were influenced by intra-service competition (consciously or unconsciously).

[VX275]

By the time of Overlord the accuracy of Bomber Command was such that the Main Force bombers were used in a tactical role (much to Harris's disgust). My father was in the infantry and witnessed first hand both daylight and night time attacks by the main force on German positions at distances as short as 1000 yards. During Operation Totalize the PFF were even assisted in marking the target by the Divisional artillery firing flares and coloured tracer.
Father had no complaints about Bomber Command's accuracy, on the other hand he was on the receiving end of the USAAF in broad daylight on a couple of occasions when well behind the front line.

[Warmtoast]

In connection with this discussion and well worth reading if you haven’t already done so is "The United States Strategic Bombing Survey" - available here:
United States Strategic Bombing Survey: Summary Report (European War) (http://www.anesi.com/ussbs02.htm#taotraw)

[ICT_SLB]

Yes indeed, but these were on a relatively small scale, and the element of estimation came in scaling them up for the future war. It would be interested to find out how much estimates of bombing casualties were influenced by intra-service competition (consciously or unconsciously).
FP
I can't find my copy but a fairly extensive exposition of the projected casualties especially as they affected Civil Defence preparations is given in "The Blitz" by Constantine FitzGibbon. Funnily enough, this book is much earlier (1957) than those on the Blitz cited by Wiki. Incidentally Wiki states that the WW1 estimates were corroborated by the bombing casualties in the Spanish Civil War.

[rolling20]

Getting back to the original thread, it must be remembered that the Luftwaffe had the advantage of plenty of practice by the time the blitz began. Condor Legion in Spain and then Warsaw, Low Countries, France etc. At the start of the war some Bomber Command navigators were enrolled at Southampton University on navigation courses! As already mentioned the Luftwaffe didn't have that far to travel and the UK being an island, navigation was fairly easy, apart from the odd FW 190 and Ju88 that landed in England having mistaken the bristol channel for the English channel. The Lorenz system was in civilian use long before the war and was used at civilian airports as a night landing aid, along also with Luftwaffe use. Which brings me nicely to the fact that there were scheduled night mail flights across Europe before WW2 and one wonders why the RAF did not utilise these for training crews? Also one must remember that out the outset of war only 4Group flying Whitley's were the only designated night bombing group. It was only after the horrendous Wellington losses in December 39 that bomber command realised that night bombing was going to be the way forward for future operations. I think I am right in saying that bomber command lost more crews killed in the first 2 years of the war, than they killed Germans. It was a steep learning curve

[Pontius Navigator]

FlightlessParrot, I missed your comment about radar bombing accuracy. A generally accepted accuracy radar attack by a V-Bomber flying straight and level above 40k and about 480kts given a discrete aiming point was about 400 yards. It was said that the operational degradation would increase that to 750yds. If it was an evasive bomb run the error might be in the region of 1000yds [l] in training[/I]

The discrimination of H2S 2, a 10cm radar, was much less than H2S 4 or H2X. The Germans also camouflaged targets such as Hamburg to cause a shift in both radar and visual aiming points.

[FlightlessParrot]

Thank you, Pontius. So what I have read, that bombing on radar through clouds was effectively area bombing, has at least an amicable relationship with the truth.

[Pontius Navigator]

FP, indeed, and of course the only operational radar bombing proved that on the Falklands. I am not sure what stick soacingvwas used but say 50 yards then the centre bomb on the stiuck that hit the runway was 500 yards off. The other stick missed the runway with a similar line error.

I was told one Valiant sqn used radar bombing and may have been close. The others made visual attacks.

[ricardian]

British Pathe 1944 report on the accurate bombing of Amiens prison (https://www.youtube.com/watch?v=_GI2AxVJbLg)

[ericferret]

Many years ago in flight magazine there was a letter which I think followed on from how small the RAF had become.
Someone pointed out that for the WW2 RAF to have the same bombing effectiveness as the current Tornado force they would have required more bombers than were available at the WW2 high point of bomber command.

I wish I had keep that as I also wish I had keep an advert from Flight published at about the same time.

Wanted... white paint for Enterprise type starship must be capable of withstanding warp factor nine.

I think someone had too much time on their hands!!!!

[Kewbick]

Most of the WW.II Allied film footage I have viewed involves the extensive day-time bombing of olive groves, fruit orchards and wheat fields. Not a single pickle barrel.

[Heathrow Harry]

Pontius - I think you'll remember that the Valiant was long gone before the Falklands - they were all Vulcans ...

and they did staddle the runway (just!) but then they were using BA INS systems they'd "acquired" IIRC that drifted something cruel......................

[reynoldsno1]

DR to help them, while dodging flak and being hunted by night fighters.
...aaaaah, the wonder of air plot ...

[Shaggy Sheep Driver]

On a tour of the Midland Hotel in Manchester recently our tour guide claimed that the hotel and the nearby town hall were deliberately not bombed in WW2 as Hitler wanted to use them after the war (which of course he expected to win).

Since the city of Manchester was bombed in WW2, I did wonder about the truth of our guide's remark, given the lack of accuracy of WW2 bombing.

[wonderboysteve]

Pontius - I think you'll remember that the Valiant was long gone before the Falklands - they were all Vulcans ...

and they did staddle the runway (just!) but then they were using BA INS systems they'd "acquired" IIRC that drifted something cruel......................

I'm far from the expert that PN is on this matter, but...

1) I suspect PN is referring to the operational use of Valiants in the Suez crisis (but I could be wrong)

2) The BA INS system (Carousel) was good enough to find the islands, but was not relevant to the bombing, which used the NBS system. Given that one of the offset points was based on the coastline (presumably uncertain), I think it is pretty amazing that the stick found the runway at all! Remarkable.

[Herod]

Wasn't the idea to bomb at an angle to the runway? That way, it was pretty certain that one bomb would hit,which was enough. If they had bombed parallel, and been only slightly off, there would have been a neat row of holes in the middle of nowhere.

[Innominate]

SSD - I've heard the same said of the Brighton Dome, Senate House in London (although a friend of ours was a firewatcher on the latter and they did get some incendiaries) and (IIRC) Cologne cathedral. To my mind, to be sure of missing a target you have to be sure that your bombs will fall somewhere else - in other words you have to hit a different target. The Luftwaffe (and most of the RAF and USAAF) were not capable of such accuracy.

I also remember reading that on one of the American daylight raids (possibly Schweinfurt/Regensburg) the aiming point was the cathedral steps...

[Plastic Bonsai]

I'm sure I read somewhere it took 30 B-17s or 17 Lancasters or 1 Mosquito to take out a No Ball site (V1 launch ramp). The Mosquito technique was a 4000lb cookie delivered from a vertical dive.