Why wasn't T-34 hull front upgraded?

[Sergei]

When T-34 was first conceived, it was just brilliant - good gun and armour, but also high speed and low ground pressure. Ergonomy may not have been as high, but still, had it been around during Barbarossa in the numbers of T-26's, Germans would have had a very difficult time. And when they did meet T-34's crewed by decently trained and led men, they were difficult to overcome.

But by 1942 the situation was already quite different as long 75's were being pushed to the front. Counter-measures are always met with new measures, and so the T-34 was over the years upgraded - turrets had better protection and room for an extra guy, radios were added, and finally the gun was upgraded. But while this was taking place, the hull remained the same. 45mm of steel at 60 degrees from vertical just wasn't sufficient any longer.

T-44 was designed to be a modernized T-34. It had 120mm armour at the front, at the same angle as in T-34. Almost a thousand were built during the war, but logistical reasons etc. discouraged from actually using them (which strikes me crazy considering that US, UK & Canadian made AFV's were happily used).

But if they couldn't replace the T-34 with a newer model, couldn't they at least have bolted some 50mm steel plates to the front and add the thickness to 95mm? I know nothing about how to calculate these things and maybe I'm wrong, but wouldn't that have made them a bit more survivable in the late war years? That's what the Germans did with PzKpfw IV's, another design with a service record lasting the whole war.

[Mattias]

They did, and the result was this:

T-43

As the text indicates though the situation had changed at the time it was ready for deployment (mid 1943), the top priority was now to mount a bigger gun. Reading about the resulting T-34/85 on the Russian battlefield site it would seem that the bigger turret and gun was already pushing the limits of the chassis, thus making an uparmoured glacis a bit much to handle.

I have seen pictures of T-34's with add on armour though, plates that have been welded directly on the hull and turret. One source (John Milsom: Russian tanks 1900-1970) shows a T-34/76B (M41 I think) with add on armour and states that these plates were 15mm thick.

M.

[flamingknives]

Something to do with overloading the suspension at the front, IIRC.

[Pzman]

It may well have been a production issue. It does seems a little strange to me as well, but they must have considered that by building them in greater numbers than the Germans could ever match it didn't matter. It could also be that the Russians just told their crews to fight from hulldown positions whenever possible so that they did not have to change the production of the hull. It also seems odd that if they had the T-44 avalible that they would hold back its use. That said even T-44's have some of the same problems and a well placed shot from a 75mm L/48 can punch its way through the front hull. (At least in CMBB)

[Bone_Vulture]

Probably the greatest problem was with the front armor of the turret: impenetrable hull armor means little if the enemy guns can still go through the turret with ease. A good example of this is the IS-2 series (in CMBB, at least).

[Denwad]

umm doesn't it go from 45mm to 70mm in 1943?

[flamingknives]

Not on the hull front. The turret armour is progressively upgraded.

It's worth noting that, according to some of rexford's posts, the thickness of the glacis could vary by as much as 10mm. I don't think that this is modelled.

[MikeyD]

There seems to be some confusion.

The T34-76 hull WAS uparmored on a pretty regular basis! Tanks rolling out of the Stalingrad factory had (12mm?) applique armor already in place. They did it specifically to match the new 75mm gun threat. See my early T34-76 mods for a couple common applique plate patterns. They didn't totally redesign the hull with thicker armor (75mm was about their factories' max rolled plate thickness in '42) because that would've involved some major retooling and in '42 they were operating in crisis mode.

By mid-war they even produced a T34-76 M43 "jumbo" with enough extra one-piece bow armor (30-35mm?) to stop an 88! Really did a number on the vehicle's mobility, though. All this happy upgrading came to an end when the heavier 85mm gun turret was introduced. The suspension couldn't take a big turret and added armor both.

[ July 27, 2004, 03:30 PM: Message edited by: MikeyD ]

[Pzman]

The thing is these extra plates aren't modeled in CM, most likely because there was no set standard in reguards to them. I guess that is why some would be led to be believe the Russians didn't attempted to do so.

[Bone_Vulture]

Perhaps in the next CM engine, we can go beyond homogenous "armor quality", and add random plating for certain tanks.

[Pzman]

It would be interesting to see. Then you could add things like a Sherman that has tons of extra tracks bolted on for extra protection and so on.

[Guest Mike]

IIRC there are accounts that the extra tracks, etc could actually degrade armour performance, by defelcting the incoming shot so that it struck the armour at closer to a right angle.

[Vossiewulf]

The Russians have a term for that Mike, they call it normalizing the round.

One of the reasons the SU-100 wasn't built in bigger numbers is that it was seriously overloaded on the front road wheel.

Mattias has it right. Thicken the glacis, need to redesign the suspension, while we're at it let's fix the turret, you end up with the T-43.

[Pzman]

Originally posted by Mike:

IIRC there are accounts that the extra tracks, etc could actually degrade armour performance, by defelcting the incoming shot so that it struck the armour at closer to a right angle.

True, it may be that many crews had it on more for moral or due to the fact that they needed to change the tracks often.

[MikeyD]

I recall lobbying for a mid-war added armor "T-34-76+" like we have late-war "Sherman +" in CMBO, but to no avail. A T34 that could just manage to defeat a 75mm gun round from the front would be mighty useful!

[Mr. Tittles]

Ive seen that BS about 'normalizing' (or the round going orthoganal BEFORE entering the armor) on the russian website. Its not physically possible. X Ray photos, like the ones in the Pantherfibel, show that a round changes direction while in the armor. The tracks would have nothing to do with that. The reason the penetrator changes direction while going through sloped armor is that it is actually finding the path of least resistance. Its actually 'bouncing' off the armor plate interior and shooting downwards (on a sloped armor like the T34 upper hull). It will bounce upwards and into the armor against a sloped armor like the lower hull.

What tracks CAN do is act as a guide so that sloped armor can be defeated. A AP round that strikes just below a track, or in a space within the track, would be guided into the armor.

My own opinion is that steel tracks are effective as long as they dont act as a guide. They will strip off caps at least. The fact that the Germans used them in such quantity must show that they did some testing and found it worthwhile.

[MikeyD]

You remind me of those soft steel 'bazooka plates' that weren't designed for bazookas at all, but were meant to cause an anti-tank rifle to tumble before striking the main armor. If spare track armor can start a round 'tumbling' (admittedly it won't tumble much in the distance it has to cover) it may keep the round from hitting the main armor pointy-side-on. And it may pre-detonate an incoming round containing a burster charge.

[flamingknives]

A track plate is what, about 1" thick? Why should that be so much different to a 2" armour plate?

More to the point, the tracks are not armour quality steel, so it can act as an AP cap for the incoming shell, as well as making it less likely to ricochet.

[MikeyD]

I'm trying to recall... What were Brit and Russian tracks made out of... manganese?

[flamingknives]

A manganese alloy steel seems likely for track links.

Manganese

[Redwolf]

The T-34 also had the drivers hatch in the sloped front, reachable by shots (as opposed to other tanks who have the hatch at the top).

You can upgrade the nose armor all you want, the hatch will always be a weak point. so it makes more sense to invest the weight elsewhere.

[MikeyD]

Another weak spot on the T34 was the ball mg mount.

One reason the T34 was never thoroughly upgraded, there were plans afoot in late '42 to replace all T34 and KV manufacture with a 'universal tank' design. The two competing designs had thicker bow armor and no vulnerable mg ball mount. The Russians were perfectly happy to keep their current 76.2mm general purpose gun... until the Tiger appeared in late '42! All their 'univeral tank' plans were instantly made obsolete because of the Tiger, and 45mm bow armor on the T-34 became the least of their problems!

[rexford]

Originally posted by Mike:

IIRC there are accounts that the extra tracks, etc could actually degrade armour performance, by defelcting the incoming shot so that it struck the armour at closer to a right angle.

A very good point.

We were sent some data a long time ago about German firing tests against armor with added track links for protection.

While I don't remember the specifics very well the track links added to the resistance at one set of angles, did nothing at the intermediate set of angles and actually degraded the armor resistance at the remaining angles.

From what the above post indicates it is a good bet that the track links decreased the resistance at high angles by rotating the round so it was closer to the armor perpendicular.

Addding stuff on top of armor is not always a good idea, as Mike points out.

We have never found any firing tests that apply to high hardness armor placed on top of other high hardness armor, which is what would occur with T34's. Firing tests against medium hardness homogeneous armor show that 15mm welded to 45mm would resist like less than a 60mm thick single plate (although two face-hardened plates in contact with resist like more than the combined thickness).

[rexford]

Originally posted by Mr. Tittles:

Ive seen that BS about 'normalizing' (or the round going orthoganal BEFORE entering the armor) on the russian website. Its not physically possible.

There is firing test proof that thin armor plates can radically change the direction of big rounds.

U.S. tests with thin plates showed that 90mm solid shot rounds were deflected enough to damage the ammo and greatly decrease their ability to penetrate spaced plates behind the thin armor.

The Panther Fibel photo's show that a horizontal round penetrating a sloped plate pierces the armor heading downward, which shows that hitting things at an angle can result in a major change to the projectile flight path.

If the Panther Fibel photo's showed a second plate sloped at the same angle as the front plate, the penetration of the first plate would actually result in the round being rotated closer to the perpendicular of the second plate.

While I don't know that much about the Russian Battlefield discussion, spaced armor can deflect and rotate penetrating rounds enough to do all sorts of things.

[rexford]

"The T-34 also had the drivers hatch in the sloped front, reachable by shots (as opposed to other tanks who have the hatch at the top).

You can upgrade the nose armor all you want, the hatch will always be a weak point. so it makes more sense to invest the weight elsewhere."

The driver hatch on the T34 was 75mm thick, which made it inpenetratable to Tiger hits at any range unless they landed near or on the edges.

German penetration drawings for Tiger 88mm ammo against the T34 front show that hits on the driver hatch were not expected to defeat the armor. Sounds like the Russians wanted to spare as many drivers as possible, and the bow machine gunner and turret crew were secondary in terms of armor protection to the driver.

My guess as to why the T34 front armor was not seriously ungraded: the tank was intended to quickly blow through infantry lines and do all sorts of damage and adding armor to protect against PzKpfw IV's and Tigers would get in the way of the main T34 mission.

We read some time back that Stalin was talking about quantity versus quality, and he stated that the life span of a tank was short and quality didn't matter much in the long run.

German tactics also stressed knocking out T34 from the side to reduce the number of return shots, and 76.2mm HE was very lethal against anti-tank guns. Putting all that plate on the front hull would save some T34 but endanger the rest by slowing them down and allowing more flank hots by the panzertruppen.