olicana | 03 Nov 2014 11:33 a.m. PST |
Given the widespread use of hollow charge AT weapons, such as the Panzerfaust, why didn't the allies adopt the simple expedient of spaced skirts like that on the PzIV H? I know about the argument of mass production over development given in 1942 about Sherman production, but the addition of 'side skirts' was such a 'cheap' addition to protection it leaves me cold to believe that the western allies thought so little of human life that such a life saver wasn't adopted. Other than cost, was there a reason? |
olicana | 03 Nov 2014 11:36 a.m. PST |
Excuse the spelling mistake in the title, obviously 'space armour' wasn't developed until the advent of Warhammer. |
Lee Brilleaux | 03 Nov 2014 11:37 a.m. PST |
I have no idea, but I love the title. Thumbs up! I expect this issue to appear on one of those cable channels where the word "History" is used, incorrectly. |
wminsing | 03 Nov 2014 11:48 a.m. PST |
Was there a lot of supporting research to show that spaced armor was actually the solution? -Will |
Mobius | 03 Nov 2014 11:57 a.m. PST |
It was Space Alien technology transfer to the Nazis. |
tberry7403 | 03 Nov 2014 12:11 p.m. PST |
The "side skirt armor" was originally developed by the Germans to defeat Russian ATRs. |
Brian Smaller | 03 Nov 2014 12:12 p.m. PST |
Maybe they figured they would just build another 50,000 tanks to replace ones knocked out. |
Black Bull | 03 Nov 2014 12:13 p.m. PST |
Because the Western Allies didn't lose tanks to the large numbers of Soviet 14.5mm Anti-Tank Rifles |
Jemima Fawr | 03 Nov 2014 12:20 p.m. PST |
As has been said, the German spaced armour was a reaction to anti-tank rifles, rather than HEAT rounds. The effect on HEAT rounds was a happy coincidence and doesn't seem to have been noticed until very late in the war, when there was a sudden appearance of mesh armour on German tanks. Had the Allies even noticed the effect of spaced armour on the relatively new-fangled HEAT rounds? I don't know. |
Mserafin | 03 Nov 2014 12:20 p.m. PST |
But you see all sorts of expedients made up by the tank crews. There are plenty of pictures of Shermans with sandbags on the front and sides. The Soviets in Germany in 1945 attached bed springs to the outside of their tanks. If you're seen "Fury" you may have noted the logs carried on the side of the vehicle, which would keep out a hollow charge round and could also be used to un-bog the tank. |
Landorl | 03 Nov 2014 1:14 p.m. PST |
If you're seen "Fury" you may have noted the logs carried on the side of the vehicle, which would keep out a hollow charge round and could also be used to un-bog the tank. They could also have a campfire and roast marshmallows. |
haywire | 03 Nov 2014 1:35 p.m. PST |
It came too late in the war for spaced armour kits to reach the front? |
boy wundyr x | 03 Nov 2014 1:52 p.m. PST |
But were the sandbags, treads, bed springs, logs, etc. specifically to stop HEAT rounds or just the tankers deciding they wanted as much stuff between them and whatever was being shot at them? |
wminsing | 03 Nov 2014 2:12 p.m. PST |
I think boy wundyr x is correct, crews wanted as much stuff between them and incoming rounds as possible, end of story! -Will |
Weasel | 03 Nov 2014 2:32 p.m. PST |
The bed springs I assume must be for HEAT purposes, since they don't seem like they'd deter a 75mm shell much, if at all. |
tberry7403 | 03 Nov 2014 3:36 p.m. PST |
Unless they watched too many cartoons and figured the springs would cause the shells to "bounce" off the tank. |
doug redshirt | 03 Nov 2014 4:00 p.m. PST |
Mines were the leading cause of tank losses by the Western Allies. Not much you can do about that. |
spontoon | 03 Nov 2014 4:07 p.m. PST |
There's spaced armour on the turrets of British Cruiser Mk. IV's. |
Lion in the Stars | 03 Nov 2014 4:11 p.m. PST |
As fast as the Americans could repair most Shermans (and replace those that couldn't be fixed), I suspect that spaced armor for either anti-ATR or anti-HEAT was a non-issue. |
PiersBrand | 03 Nov 2014 4:30 p.m. PST |
Waffen Revue Nr. 40, S.6457ff03.12.1944 the WaPrüf had the HASAG in Leipzig conduct trials with Bazooka, Panzerfaust, Panzerbüchse 39 (With rifle cup using Hohlladung) and PRTD . In that test armour plates are used, protected by plate and mesh Schürzen. Verdict: No effect. 21.12.44 another test was done at Kummersdorf. This time using real tanks, a Pz. IV and a Sherman with Schürzen. Same result. Late war German tests seem to have found the side skirts did literally nothing to infantry AT warheads, and they knew that from earlier tests with the AT grenades and could in some tests increase effectiveness as evidenced in one of the German trials.
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dragon6 | 03 Nov 2014 4:45 p.m. PST |
and could in some tests increase effectiveness as evidenced in one of the German trials. Yes, standoff distance. Hollow charge wasn't well understood in WW2. But that's why modern HEAT rounds have those long spikes to detonate the round at the proper distance from the armour. |
Mark 1 | 03 Nov 2014 4:53 p.m. PST |
As others have mentioned, German schurzen armor was not developed as a defense against HEAT rounds. Rather, it was a defense against Anti-tank rifles and medium-caliber HE rounds. The Russian 14.5mm ATRs penetrated up to about 40mm of armor. So Pz III and IV were vulnerable from the side and turret rear, as was the Panther for the lower side hull (above the track, below the sloped plate). HE rounds up to 75mm could penetrate up to about 30-40mm of armor just by their explosive effect, and if they didn't penetrate they could cause significant damage from spalling. But ATR rounds had a tendency to rotate after passing through the 5mm schurzen, striking the actual armor plate from a side-on angle. This greatly reduced the effectiveness of the ATR round. And HE rounds would destroy a schurzen plate, but leave the armor behind it un-touched. Notice that the Germans almost never put schurzen armor over any plate that was thicker than 40mm …. because anything more than 40mm could resist a Russian 14.5mm ATR or a 75mm HE round all by itself. When a HEAT round detonates, the shape of the charge forms an explosive jet that blasts it's way through armor. That jet focuses to it's maximum effectiveness some distance in front of the charge. In WW2 HEAT rounds did not have stand-off fuzes. So the net effect of spaced armor was to make most HEAT rounds MORE effective, not less. Schurzen plates offered little resistance, but detonated the round at a reasonable stand-off distance from the main plate, so that the jet could be fully formed and focused when striking the actual armor. What spaced armor did do effectively was pre-detonate APHE rounds. US testing at Shoeburyness prior to D-Day indicated that spaced armor could initiate the fuze, causing US rounds to detonate in the space between the spaced armor and the actual armor plate, rather than penetrating and detonating inside the enemy tank. It was therefore recommended that the explosive filling and fuzes be removed and and inert filler used, turning the rounds from "shell" to "shot". However the testing was done using 20mm plates spaced off of 50mm plates … evidently in an effort to test effectiveness against German Vorpanzer spaced armor, not Schurzen spaced armor. Vorpanzer was actually quite rare, being mainly used on early Pz IVd and e models, and little seen later in the war. In any case the problem did not seem to arise in combat, as US tanks and guns never really showed much of a problem penetrating and destroying Pz IVs. So US APHE rounds were very seldom converted to inert shot. The later war screen armor, bedsprings, etc. were effective against HEAT rounds for a different reason altogether. They had a tendency to defeat the fuzing of HEAT rounds. So also logs and sandbags could do this occasionally. It was as much the textures of these ad hoc appliques as it was their "stand-off" nature. It was not that they provided spaced armor, but that they were not flat plates. In some cases projectiles might strike first with their sides, rather than their noses. In other cases the material might give as the round struck, allowing the round to turn so that it is not pointing straight into the plate before sufficient resistance caused the fuze to ignite the round. This is also similar to how slat armor works on modern armored vehicles. The goal is to have the HEAT round strike first with some part of the projectile OTHER THAN the nose. This can defeat the fuze or turn the round before the fuze operates. Or so I have read. -Mark (aka: Mk 1) |
Mobius | 03 Nov 2014 5:36 p.m. PST |
PTRD/PTRS anti-tank guns firing BS-32 solid steel core bullets could yaw when passing through skirts. The later BS-41 tungsten cored bullets penetrated more but were often damaged when passing through skirts thus failing when they continued to the tank side armor. |
lapatrie88 | 03 Nov 2014 7:13 p.m. PST |
Did I not read of the U.S. M10 having bolts to fit an outer skin of armor sheet? This was in a 1943 picture book of American armored vehicles. |
Zagloba | 03 Nov 2014 7:43 p.m. PST |
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Mark 1 | 03 Nov 2014 8:54 p.m. PST |
Did I not read of the U.S. M10 having bolts to fit an outer skin of armor sheet? Yes, the early production M10s had bolts for add-on armor. I don't know if this was expected to be spaced or just thicker armor. The add-on armor was not mass produced nor put onto any M10s in combat zones. Later production M10s no longer had the bolts. My guess is that the bolts were put on the M10 out of bureaucratic indecisiveness. It's not like the turret-side armor was thick enough to resist any AT projectile in 1943. What they might have considered bolting on would have been unlikely to make it particularly resistant to German AT weapons. But somewhere in the requirements / development / production / approval process someone said "just in case … couldn't hurt!", and so there they were. -Mark 1 |
Mobius | 07 Nov 2014 6:11 a.m. PST |
Tango, the Pz III added spaced front armor plates are more in the nature of applique armor. It was added to defeat the British 2 pdr and Russian 45mm. |
Yourbitterpill | 07 Nov 2014 7:29 a.m. PST |
@Mark 1: Thank you, fascinating stuff. |
Lion in the Stars | 07 Nov 2014 11:04 a.m. PST |
If anyone has heard of p90 armour it was spaced armour full of holes in an attempt to increase the chances of an AP round tumbling and slapping the main armour sideways. P90 was a concept I heard about during my research time with light armour research – not sure if it was ever implemented. I think they're calling it "Super Bainite" these days… |
miniMo | 09 Nov 2014 12:23 p.m. PST |
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Archeopteryx | 19 Nov 2014 6:13 a.m. PST |
I agree with Tango 2-3 ditto. Spaced armour is not the same as side skirts, or slats. Applique, just refers to any post-manufacture extra bolt on armour – it does not refer to how it works. Spaced armour is a means (like angled plates) of making the most of a given thickness of steel, as Mark1 has described. The space is important, as is the angle in sloped armour, in trying to get a deflected detonation or maximising the thickness of steel exposed to the impact. Skirts were very thin – not really armour at all – and about protecting vulnerable areas from ATRs as everyone has said. They were of course spaced, but I think when most references speak about German spaced armour they are taking about the extra plates on the glacis and mantle of Pz. IIIs and IVs, not side skirts. Of course I could be wrong |
Murvihill | 19 Nov 2014 11:00 a.m. PST |
Armor made of multiple sheets of thinner material aren't as strong as a single sheet of thicker armor. While both sides did it (IIRC some US workshops welded on pieces of armor from destroyed tanks to their Shermans?) it was usually an ad-hoc reaction rather than something to be emulated. |