Ju-87 Stuka vulnerability to fighter attack

[Nikademus]

Originally Posted by HoHun

Hi Nikademus,

>The thicknesses appeared enough to provide the same "ping" effect described by Wildcat pilots who recounted their experiences being riddled by gunfire.

Hm, do you know the actual thickness for the SBD? I didn't find anything on that, I'm afraid.

Regards,

Henning (HoHun)

Hello.

No, Lundstrom did not mention specific thicknesses. Some of the battle accounts describing Zero attacks on SBD's matched descriptions on attacks of the F4F's. From these it would appear the SBD displayed similar ruggedness in the face of being sprayed by 7.7's and the occasional. The 7.7's had a hard time even when many hits were scored. Cannon hits did better but didn't always lead to the plane's demise. (not immediately at least) During Coral Sea, a VS-5 element endured a Zero attack which was pressed home. Despite numerous hits none were lost. Specific mention was made that the self sealing tanks in particular had handled 7.7mm hits very well. (hence my curiosity about how well Stuka tanks fare under similar hits)

[B-17engineer]

How'd we get from Stuka to SBD's and Zero's fighting in a completly different thearte

[Nikademus]

Originally Posted by JoeB

1. Several 2 plane scouting sections VB and VS-10 at Santa Cruz that separately made contact with the Japanese CAP claimed 7 Zeroes without loss, at least one to fwd guns in a 7 v 2 encounter by the VS-10 CO, though none of those claims check out apparently. The team of Strong and Irvine did however score at least one 500# hit on Zuiho, following by a several on 2 where their rear gunners claimed a Zero each, and both returned safely.

Lundstrom confirms the latter. Nakagami Koichi's 17th Shotai Zero being downed by an SBD. The 2nd A6M appears to have indeed used it's forward guns. This due however to an unusual diving head on attack made by 13th Shotai leader Omori. The defender was Ltcr William Widhelm who simply fired his forward guns and set Omori's engine on fire.

I read Lundstrom as verifying fewer victories for SBD's than you mention and the only clear Zeroes IMO were two of the CAP over Shokaku and Zuikaku v formation of VS and VB 8 at Santa Cruz.

I'm rechecking Lundstrom. The 3rd Zero may be an error or a ditching due to damage from an SBD. (PO3c Tochi.....if the latter i count it as a kill)

2. I'd comment on R Leonard's tally of F4F-4 air combat losses at Casablanca(on the thread linked by Plan D above) as follows based on the detailed blow by blow in Cressman "Ranger":
"In aerial combat:
...
F4F (VF-41) Ens CE Mikronis to H75A, WIA, POW (said his engine was ko'd by AA in the strafing/air combat encounter over Cazes 11/8 )
F4F (VF-41) Lieut.(jg) CA Shields to H75A, POW (yes)
F4F (VF-41) Lieut GH Carter, ditched due to damage from H75A (yes)
F4F (VF-41) Lieut. MT Wordell to H75A, POW (downed by warship AA later the morning of 11/8 )

to AA fire
...
F4F (VF-41) Lieut.(jg) CV August, POW (like Mikronis could have been AA or fighter bullets over Cazes, but August didn't claim to know which)
..."

and I'd add
probable air combat loss:
F4F (VF-9) Ens CW Gerhardt of VF-9 ditched after an oil leak that appeared following the 11/9 combat with GC I/5 H75's.
possible air combat loss:
F4F (VF-41) Ens AD Conner, was in the 11/8 VF-41/GC II/5 combat, claiming an H75, ditched after the mission but cause not given in any source I know.
non air combat loss:
F4F (VF-9) Ens LA Menard: implied combat loss in the 11/9 combat in Lambert, but seems purely operational in Cressman.

This would match what Shores wrote. a total of 7 F4F's. One of the seven includes Gerhardt and a pilot of VGF-29 who reported that his oil line had been cut and then was never heard from again. Shores suspects he fell afoul of a French fighter.

I was able to confirm 5 F4F's to AA. Total losses listed for F4F's stated as 25.

The French plane losses in the two well known combats aren't certain AFAIK, from French sources in Lambert GC II/5's losses 11/8 were 5 pilot KIA, 1 WIA parachuted, 1 WIA 'landed roughly', 1 WIA plane fate not given, several other planes inoperative. The losses of GC 1/5 11/9 are given in Cressman as 2 pilot KIA, 1 pilot 'seriously burned', 2 'force landed'. French sources say the Armee de l'Air didn't use its Dw.520's though VF-41 claimed some in the first combat.

According to Shores, Flotilla IF's CO Vaisseau Folliot was shot down in his D.520 by Wildcats. The other 10 were Hawks though.

[HoHun]

Hi Nikademus,

>Also, the "Parties" began even in the days of rifle only armed fighters.

But we don't know the armour status for the early Stukas, so we can't draw any conclusions on this for lack of data.

>It also only deals with the Ki-43-I. When mentioning the Oscars in the examples i've cited here and in prior threads I am referring to the Ki-43-II.

That might indicate that the Ki-43-II could have two 12.7 mm machine guns indeed, but unless they changed their synchronization technology too, it would still be a 12.7 mm not much more effective than the 7.7 mm of the Ki-43-I. (But that's really going off topic here

>My point was that they cannot simply be dismissed and the early (orig) crop of Japanese fighter pilots were able to put them on target very well, including hard deflection shots.

Hm, how could we know? Those targets who were hit really well would not return so you'd not know what brought them down, and those who did return were by definition not hit well. Not to say that cannon were not effective, just that I don't think there's much reason to assume that their effectiveness is not accurately portrayed by the technical firepower figures (based on total muzzle energy):

Hurricane/Spitfire I   0.70 MW
F4F-3                  1.14 MW
A6M2                   1.22 MW (ca.)
F4F-4, P-40E           1.70 MW
Spitfire VC            2.40 MW
Hurricane II           4.25 MW

>I would also factor in that a Spit or Hurr has an increased vulnerability to the engine/radiator being liquid cooled vs. a radial.

You couldn't stop an attack by a cannon-armed fighter by piercing its radiator, though. It might be minutes before the fighter pilot even notices. Besides, I have never seen data that actually proves the assumed greater vulnerability of liquid-cooled engines. It might be a case like the supposed greater survivability of the B-17 over the B-24 that many people take for granted, while 8th Air Force statistics show that the B-24 actually did better.

>This would be a factor in support of posters like Kurfurst who feel the Stuka simply suffers from bad PR in terms of it's vuln.

As I don't Shores can prove his point, I tend to agree with his statement being bad PR, though I'm sure he merely reflected the contemporary RAF thinking. One would really have to look at each "Stuka Party" independendly and in detail to see if any conclusions regarding the success of different tactics are possible.

>For the SBD, it's primary opposition was naval, and there were only four carrier clashes where enemy fighter opposition was occured in all of 1942. Lunga saw SBD's basing there but they operated primarily at night vs naval targets, no or little fighter opposition.

How many engagement between SBD formations and Japanese fighters were there in all? If we're talking about SBDs in pennypacket numbers as for the A-24 variants, I'm not sure that this enough of a data basis for serious statistics ...

Regards,

Henning (HoHun)

[HoHun]

Hi Nikademus,

>Specific mention was made that the self sealing tanks in particular had handled 7.7mm hits very well. (hence my curiosity about how well Stuka tanks fare under similar hits)

The Me 110 analysis indicates that the tank in that aircraft, supposed to be of 1939 construction, sealed 4 out of 5 shots from 7.62 mm ammunition fired in single shot mode. A burst of five shots fired into another tank resulted in three hits, only one of which sealed though the leaks were slow.

I'd expect the Stuka tanks to be similar in construction to these Me 110 tanks at least for the Battle-of-Britain era Stukas.

Regards,

Henning (HoHun)

[Glider]

I don't think that there is any doubt that having an in line engine does make you more vulnerable to damage and loss. If only because there are two ways of stopping the engine, hit the engine or hit the cooling system and if you don't have a cooling system you are clearly less vulnerable.

This argument will of course apply to any in line engine (with the exception of the 190 due to its radiator being in front of the engine) not just Hurricanes and Spitfires.

Taking this a step forward, this must apply to any comparison between the Dauntless and the Ju87 as one is a radial and the other an inline.

Personally I do not believe that the Ju87 was more vulnerable than any other dive bomber, they all tended to be slow and lack defensive fire power. To compare these two, the additional armour on the Ju87 probably balanced out the vulnerability of the radiator. Any difference would be marginal and probably depend on the tactical situation.

Any light bomber is vulnerable to heavily armed fighters of any nation.
The Japanese Ki43 would have had a problem due to its design and being particually vulnerable to any return fire due to its light structure. 2 x LMG wouldn't worry most fighters once armour and sealing tanks were the norm, but the Japanese were vulnerable.

[Kurfürst]

I would like to know more about these so called 'Stuka parties'. Did they only exist in the RAF folklore perhaps, ie. cases when fighters were claiming ridiculus amounts of Ju 87s shot down compared to the actual losses? I`d certainly like to see examples.

This might of interest, since this is the official British PoV about the Stuka, issued for RAF pilots as a tactical recommendation :

HINTS IN ATTACKING VARIOUS TYPES OF GERMAN AIRCRAFT, FROM EXPERIENCE GAINED OVER ENGLAND AND NORTHERN FRANCE

JU.87.

5. It has not proved possible for monoplane fighters to attack the Ju.87 when it is dive bombing, as owing to the steep angle of dive and the slow speed attainable with the diving brakes, our fighters over-shoot. It is therefore recommended that fighters should try to attack the Ju.87 before it commences to dive, or, failing this, when it has pulled out of its dive.
The Ju.87 has been found to be well armored behind and below the rear gunner so that attacks from directly astern and below are less effective. Formations of Ju.87's are usually preceded, or accompanied, by large fighter escorts which endeavour to distract the attention of our fighters.

- Deputy Directorate of Air Tactics (Air Ministry), March, 1941.

This would be an early Stuka, Bertha model.

[Crumpp]

(with the exception of the 190 due to its radiator being in front of the engine)

Liquid exchange oil coolers are a "feature" on all aircraft. Just to keep some perspective.

[HoHun]

Hi Glider,

>I don't think that there is any doubt that having an in line engine does make you more vulnerable to damage and loss.

I do not know of any combat statistics that would quanitfy the point, so even if it migth be true qualitatively, there is no way to tell if the effect was significant quantitatively. I don't think that there is any doubt that aircraft like the Typhoon or the P-40 were very rugged despite their inline engine, so maybe the advantage of having a radial engine was not that great. Who could tell without data?

>To compare these two, the additional armour on the Ju87 probably balanced out the vulnerability of the radiator. Any difference would be marginal and probably depend on the tactical situation.

Oh, well. Personally, I'd not dare to make statements about two factors balancing each other unless I could quantify the individual factors.

According to "Wings of the Luftwaffe" by Eric Brown, the radiator of the Ju 87D-3 was armoured, by the way.

Regards,

Henning (HoHun)

[Hop]

Myth. And it was shattered far too many times.

The Stukas were neither withdrawn, neither there were 'steady losses'. The loss rate was quite acceptable, and they had major successes during the Battle.

Where has this "myth" been "shattered"?

The truth of the matter is that the Luftwaffe suffered very high stuka losses during the BoB, and withdrew the type from combat over Britain, later on using them for attacks on shipping under favourable conditions only.

From ER Hooton, Eagle in Flames:

The same day ended Stuka daylight operations over England when four fighter squadrons slaughtered Major Clemens, Graf von Schonborn's StG 77 during an attack upon Poling radar station, with 16 Stukas last and two damaged beyond repair (21% of the force) in what Seidemann justly described as "a black day"

Wood and Dempster, Narrow Margin:

August 18th was the virtual death knell of the Ju 87s over Britain. Losses had been mounting at an alarming rate and, apart from a few isolated sorties, they were pulled out of the battle

Stephen Bungay, Most Dangerous Enemy:

Most unusually, Luftflotte 3's post-action report the next day (always called an Erfolgsmeldung - literally a "Success Report") commented on the losses of the Stukas. It attributed them to "British fighters gaining a local superiority due to particularly favourable weather conditions" and carrying out a pursuit up to 30km over the the Channel. StG 77's air corps commander, von Richthofen, confided to his diary that a "Stuka Gruppe has had it's feathers well and truly plucked".

What really struck von Richthofen were not the overall losses of the Stukas, which at 15% were high but bearable in the short term if they were achieving results, but the near destruction of one Gruppe, whose losses ran at 50%. This was on top of the losses of nearly 30% to another single unit, I/StG2, in the Tangmere raid on the 16th, and the loss of 70% of one Staffel of II/StG2 on the 13th. Earlier losses, such as those over convoy Peewit, had been heavy but acceptable. It was becoming clear, however, that any unlucky Stuka unit caught without its escort would be almost wiped out. It was also becoming clear there was at least one such unlucky unit on every major sortie. Some rethinking was called for.

Rich from the Dupy Institute quotes Ju 87 numbers from the Luftwaffe records:
10 May 360 on hand, 326 operational
13 August 347 on hand, 276 operational
7 September 161 on hand, 123 operational

Wood and Dempster give "dive bomber" losses as:
Month - On Operations - Not on Operations
July - 16 - 5
Aug - 51 - 7
Sept - 2 - 7
Oct - 0 - 6

We can see two things from that. Firstly, moderate losses in July, very high losses in August. Secondly, either the Stuka became almost invulnerable, or the Luftwaffe did not use them much after August.

In fact, the latter is true. From Bungay again, quoting Goering:

"Until the enemy fighter force has been broken, Stuka units are only to be used when circumstances are particularly favourable." With this withdrawal of the Stukas from general operations, the only precision bombing instrument the Luftwaffe had left was Erpro 210

Now, there are plenty of authors who say Stuka losses were very high, leading to their withdrawal from combat. I've only ever seen that view rejected by a few forum posters. What is the evidence, or even opinion, to the contrary?

[Njaco]

Kurfurst, I believe one of those "Stuka parties" was on Aug 18, 1940 where numerous Ju 87s were shot down and in following the RAF protocol that you posted. Most caught just coming out of their dives. As I posted "On August 18, 1940, 109 Ju87s from StG 3 and StG 77 attacked airfields and radar stations on the east coast of England, supported by Bf 109s. 30 Stukas, nearly 21% of the total force committed, were shot down."

I am in no way claiming the Stuka was withdrawn because of this but I would say that was one party.

But looking at this thread would the Ju 87 have a slight advantage based on this ;

Graeme - “US Navy legend has it that pilots (of SBDs) were prone to ‘target fascination’ which could lull them into failing to pull out of the dive in time.”

The Ju 87 had an automatic pull-out whereas I am assuming the US SBDs did not? Would that be an advantage?

[Negative Creep]

Were the Stukas really getting results against mainland targets? If I remember correctly only one radar station was taken out of action and even then it was only for a short period. Luftwaffe strategy of attacking RAF airfields and factories would seem to be better suited to medium bombers than the Ju 87

[Glider]

Originally Posted by HoHun

Hi Glider,

>I don't think that there is any doubt that having an in line engine does make you more vulnerable to damage and loss.

I do not know of any combat statistics that would quanitfy the point, so even if it migth be true qualitatively, there is no way to tell if the effect was significant quantitatively. I don't think that there is any doubt that aircraft like the Typhoon or the P-40 were very rugged despite their inline engine, so maybe the advantage of having a radial engine was not that great. Who could tell without data?

The RAF considered the Radiator to be a weak spot, on the Mossie the Radiator was a weak spot, on the Typhoon the Radiator was seen as a weak spot, Rugged yes but hit the Radiator and you were going down. This applied to all aircraft with a Radiator.

>To compare these two, the additional armour on the Ju87 probably balanced out the vulnerability of the radiator. Any difference would be marginal and probably depend on the tactical situation.

Oh, well. Personally, I'd not dare to make statements about two factors balancing each other unless I could quantify the individual factors.

Its impossible to quantify such differing factors, but the fact remains that the Radiator is a weak spot that the Dauntlass didn't have, but the Ju87 had armour the Dauntlass didn't have in such quantity.
It can only be an opinion that one would tend to balance the other out and its one that I hold. You can disagree certainly, but it is a valid point.

According to "Wings of the Luftwaffe" by Eric Brown, the radiator of the Ju 87D-3 was armoured, by the way.

I know, but it wouldn't stop a 20mm or almost certainly a 12.7 fired at the sort of ranges common in air combat. It would give you a fair degree of protection against LMG bullets.

The Radiator increases the size of the target area that will bring down the plane. My comment about the 190 was that by putting the radiator in front of the engine, the increase in the size of the target area is minimised.

[HoHun]

Hi Glider,

>Rugged yes but hit the Radiator and you were going down. This applied to all aircraft with a Radiator.

Rugged just means having small or few weak spots. Having a weak spot of one particular type does not automatically make an aircraft "non-rugged". And radial engines have a radiator as well, though it's usually called "oil cooler" there.

>Its impossible to quantify such differing factors

It's impossible to quantify without sufficient data ... any attempt to do so is pure speculation.

>I know, but it wouldn't stop a 20mm or almost certainly a 12.7 fired at the sort of ranges common in air combat.

How do you know? The thickness is not even given in Brown's book.

And considering that rear attacks are typical for air combat against slower aircraft, and the Stukas would usually try to manoeuvre to bring its rear guns to bear on the attacker, oblique impact engines on the armour seem more likely than perpendicular hits. A relatively small armour thickness is sufficient to protect against glancing hits, and the exact amount of protection would depend on the exact armour thickness.

>the fact remains that the Radiator is a weak spot that the Dauntlass didn't have

As Crumpp pointed out, the Dauntless certainly did have an oil cooler. The radiator of the Stuka was armoured, the oil cooler of the Dauntless was not.

>The Radiator increases the size of the target area that will bring down the plane.

Having a radial engine increases the size of the target area that will bring down the plane, too. (Of course it depends on aspect, but as you're talking about areas, that's implied already.)

Regards,

Henning (HoHun)

[Glider]

Originally Posted by HoHun

Hi Glider,

>Rugged yes but hit the Radiator and you were going down. This applied to all aircraft with a Radiator.

Rugged just means having small or few weak spots. Having a weak spot of one particular type does not automatically make an aircraft "non-rugged". And radial engines have a radiator as well, though it's usually called "oil cooler" there.

>Its impossible to quantify such differing factors

It's impossible to quantify without sufficient data ... any attempt to do so is pure speculation.

>I know, but it wouldn't stop a 20mm or almost certainly a 12.7 fired at the sort of ranges common in air combat.

How do you know? The thickness is not even given in Brown's book.

And considering that rear attacks are typical for air combat against slower aircraft, and the Stukas would usually try to manoeuvre to bring its rear guns to bear on the attacker, oblique impact engines on the armour seem more likely than perpendicular hits. A relatively small armour thickness is sufficient to protect against glancing hits, and the exact amount of protection would depend on the exact armour thickness.

>the fact remains that the Radiator is a weak spot that the Dauntlass didn't have

As Crumpp pointed out, the Dauntless certainly did have an oil cooler. The radiator of the Stuka was armoured, the oil cooler of the Dauntless was not.

>The Radiator increases the size of the target area that will bring down the plane.

Having a radial engine increases the size of the target area that will bring down the plane, too. (Of course it depends on aspect, but as you're talking about areas, that's implied already.)

Regards,

Henning (HoHun)

I am aware that there are such things as oil coolers, I am also aware that on the vast majority of aircraft these are a heck of a lot smaller than a radiator. Also they don't often stick out into the airflow to anything like the degree of the Typhoon, P51, Spitfire, 109 or most other in line types

However I do have to admit to allowing myself a smile at your comments about armoured radiators.
To have the level of protection your hinting at, the Armour on a Ju87 Radiator would dwarf that on an Il2, loads of which were shot down my 20mm. Not likely.