Interesting T34 automotive facts..

[Yoozername]

http://www.dupuyinstitute.org/ubb/Forum ... 00044.html


A recent article by Boris Kavalerchik about the assessment appeared in the Russian-language magazine Voenno-Istoricheskiy Arkhiv, issue No. 1, 2006. I found a couple of things striking. First of all, and this is not the striking part, Kavalerchik says that contrary to popular opinion in Russia which holds that the T-34s which were sent to the US and England were intentionally not of the highest quality, in the spring of 1942 five T-34s were specially prepared using the highest quality parts at the Ural Tank Factory (UTZ), which at that time produced the best T-34s in Russia. These five tanks were better than regular T-34s. One was sent to the U.S., one to England, two to the front, and one to the Peoples Commissariat for Tank Production and can now be found mounted on a pedestal in the yard of the Central Museum of the Armed Forces in Moscow.

The striking part of the article, to me at least, is this part, which comments on Aberdeen’s finding that the T-34 broke down beyond repair after 343 kilometers due to dirt getting into the engine’s cylinders. Apparently this was very good!

“There was nothing unusual about a tank breaking down after such a short period. At that time T-34 tanks were guaranteed not to break down for 1,000 kilometers, but in practice this number was unattainable. According to a report by the Scientific Institute for Armored Equipment (NIBT) to Ya. N. Fedorenko, the chief of the Red Army’s Auto-Armored Directorate, the average distance a T-34 traveled before requiring overhaul (capital repairs) did not exceed 200 kilometers. The Aberdeen T-34 exceeded this.

In 1942 the quality of Soviet tanks had significantly fallen for many understandable reasons. These included the difficulty of reestablishing production by the evacuated factories at new locations, factories switching over to new production, the loss of many supply lines and sources of raw materials, a sharp drop in the average qualification of workers due to losses among experienced workers and the hiring of many new, inexperienced workers including women and teenagers. These new workers worked tirelessly and did everything they could for the front, but they were not qualified. Producing the most tanks possible was the priority, which was understandable since the heavy losses of the initial part of the year had to be made up. Therefore the requirement for quality was reduced, and the military accepted any tank that was built. As a result, in 1942 some 34’s could only go 30-35 kilometers before needing an overhaul.

To a certain degree this was justified because tanks, as a rule, did not survive until the expiration of its overhaul life, short as that was. The life of a tank on the front line was not long – on average 4-10 days (not counting time spent in transit on rail road and being repaired), or from 1-3 attacks. In 1942 the average mileage before being put out of service due to combat was 66.7 kilometers, which was less than half the average mileage before needing an overhaul. The majority of tanks simply didn’t live long enough to break down.

The V-2 diesel engine which equipped T-34s and KV-1s was still suffering growing pains. At that time its designers were struggling to extend the diesel’s service life to 100 hours, but in reality it seldom lasted more than 60. The engine of the T-34 which was tested at Aberdeen broke down at 72.5 hours, of which 58.45 were under load and 14.05 were while idling. The KV’s diesel lasted 66.4 hours. One of the deficiencies of the B-2, besides a short guaranteed life, was an increased fuel consumption (12% above norm), and, especially, a completely unacceptable over-consumption of oil, which exceeded existing norms by 3-8 times! Therefore the range of a T-34 in 1942 was limited not by fuel, but by oil: according to the averages at that time from the technical department of the People’s Commissariat for Tank Production, a T-34 carried enough fuel for 200-220 kilometers, but oil for only 145. At the same time German and American tanks didn’t require any additional oil; it was simply changed every 2,000 kilometers.”

[Yoozername]

From: EVALUATION OF THE T-34 AND KV TANKS BY ENGINEERS OF THE ABERDEEN PROVING GROUNDS, SUBMITTED BY FIRMS, OFFICERS AND MEMBERS OF MILITARY COMMISSIONS RESPONSIBLE FOR TESTING TANKS
The tanks were given to the U.S. by the Soviets at the end of 1942 for familiarization.

Regarding the T34/76 Turret

The main weakness is that it is very tight. The Americans couldn't understand how our tankers could fit inside during a winter, when they wear sheepskin jackets (Americans tested the T-34 with a two-men turret - Valera). The electrical mechanism for rotating the turret is very bad. The motor is weak, very overloaded and sparks horribly, as a result of which the device regulating the speed of the rotation burns out, and the teeth of the cogwheels break into pieces. They recommend replace it with a hydraulic or simply manual system.

[Neilster]

That's interesting. I always thought of the T-34 as a bit crude but reliable and long ranged. The sort of steed one would want while rumbling across the steppe in the depths of a Russian winter, exploiting a breakthrough.

Did their reliability improve markedly later on though? The Ruskies did do lots of deep penetrations (no sniggering in the back row!).

Cheers, Neilster

[Yoozername]

ORIGINAL: Neilster

That's interesting. I always thought of the T-34 as a bit crude but reliable and long ranged. The sort of steed one would want while rumbling across the steppe in the depths of a Russian winter, exploiting a breakthrough.

Did their reliability improve markedly later on though? The Ruskies did do lots of deep penetrations (no sniggering in the back row!).

Cheers, Neilster

1942 was probably the low point since the Soviets had moved the plants and been disrupted. They were also pressed to make as many tanks as fast as they could. Anytime you want numbers, quality is going to go down.

The war in the east was also a war of railroads. Panzer Divisions and Soviet Armies would move about as much as they could on rail. Armor is also tied to support units. They need a lifeline of fuel, ammo, parts, etc. All heavy and slow moving.

The Soviets liked the Sherman just because it was such an excellent automotive vehicle. It was a natural exploitation tank. They actually ran them till the rubber came off the roadwheels. The sherman had narrow tracks and its ride was smoother than a T34. The T34 with its tracks was actually better on softer terrain. It wasn't a road warrior.

As the war ground on, the Soviets MUST have improved the T34 in all aspects. Diesal engines, if made right, last a long time. The early V2 diesal sounds to have been made so sloppily that oil was being consumed at great rates. Since they used an aluminum block (or some other non-ferrous block?), they probably did not get the expansion rates of the metals right.

By the time they could mass produce T34/85, they had a modern tank that could outlast most German armor. I believe the Soviet decision to focus on T34 tanks, including the decision to stick with the 76mm 2 man turret as long as they did, was much better than the German multi-tank fiasco. The t34/85 needed very little retraining (unlike the Panther where whole battalions had to be withdrawn and retrained).

[Yoozername]

I suspect these 'lawn-mower' engines gave off some clouds of smoke.

[Neilster]

I've read that the vast clouds of (from memory) white smoke they gave off in winter weather was a major tactical disadvantage.

Cheers, Neilster

[Yoozername]

Most diesels give off clouds of black smoke under load. If there is substantial oil blow-by the piston rings or water is getting from the cooling system to the combustion chamber, then you see those white clouds.

Some tanks even have oil injection nozzles for squirting fuel into the exhaust intentionally to make smoke.

But I suspect that T34s were so smoky that the first wave of tanks in an attack would blind the next wave.

German recon would certainly pick them up at range for sure.

[Yoozername]

I suspect the T34 deseign may have been the most repairable tank of WWII. If nothing else, the Soviet focus on T34 production allowed commonality of parts.

The rear engine and transmission/drive combination removed these automotive elements from the front of the vehcile. It also had the brakes in the rear also. This gave a roomier/cooler space for the driver/bow-gunner.

An interesting phenomena of the sloped frontal armor on the T34 is that rounds that DO penetrate will actually come through the plate at a near 90 degree angle. What this does is directs the round away from the internals of the tank. German reports state as much. they say that it is difficult to burn a T34 from the front. Its bad news for the driver and bow gunner but I do not think that made Soviet leaders lose much sleep.

To service and repair the transmission and other rear items, the whole rear armor plate could be removed. This is the plate that the mufflers ran through. The radiators and engine are under armor/baffles but the cooling fan area is only under a armored flap (that a crewman could open and close).

Some people claim that the Soviets did not bother retrieving and repairing/salvaging AFV. That is pure BS. The Germans reported that the Soviets made as much an efforrt as they themselves did to repair/retrieve AFV.

The Soviet use of Diesal fuel was a very smart decision. The Soviets had oil but refinement was a problem. Refining diesal and low octane gasoline was within their capabilities. The US mostly supplied the USSR with high octane aviation fuel by the way.

Diesel is harder to ignite (but burns just as well if you do ignite it). It is much safer than gasoline which accounted for many explosions and burns of tank crewmen (many non-battle casualties by the way).

The T34 ammunition storage (on the floor) was an achilles heel. The lower side armor of the T34 was probably the target of AT gunners. A hit on the ammo was a near sure thing then. Once the ammo started to burn, it was just a matter of time before the T34 popped its top. The explosive used in the HE shells was volatile it seems. Catastrophic detonation where vehicles are blown apart is almost always a function of multiple HE shells detonating sympathetically.

The Soviets lost (total write-offs) 10's of thousands of afv a year in the war. Most people should realize that there were many knock-outs that were repaired (and these should not be counted in the stat of TWO). The Germans had their work cut out for them on the eastern front. My contention is that TWO and KO of Soviet AFV may actually have been in the 30K a year range.

[Neilster]

Ever seen photos of T34s with spare transmissions strapped to their backs?

Cheers, Neilster

[Neilster]

These historical photographs of the T-34 should clear a few things up.

Cheers, Neilster

[Neilster]

Reloading...

[Neilster]

Undergoing field repair...

[Marc von Martial]

The above models were quickly removed from the battlefield, it was way to easy to attach sticky bombs to them [;)]

[Yoozername]

This images shows the flaps that allowed an internal crewman to allow the blower to evacuate air (which was drawn in over the engine/radiators). These are not baffles. In another thread, a misinformed poster was claiming as much (excess alcohol and sugar in theat person's diet).

A person also added..




Since I have been in and around a few T34 (85) I can lend some insight.

The louvres are actuated from inside the fighting compartment. The picture shows them fully opened. They have an angle when opened such that a person standing directly on the back of the tank, looking forward, can see the back of the engine. The rear of the engine has a flywheel and a blower type fan. You can also see things like the air filters, starter, etc. The fuel tanks are on either side.

The transmission, in relation to the louvre drawing, is actually much further back. It sits lower and is inline with the two rear 'wheels' (actually drive sprockets). It would be outside the drawing and lower.

The louvres are not access hatches but an air inlet port. The linkage is quite flimsy and I believe that there are springs involved.

To get to the transmission, you must remove the whole rear armor plate that the exhaust goes through. It is actually in a dead air space and suffers from heat. The air flow from the blower intakes behind the turret and expells through the louvres. The bulkhead between the engine and transmission has a very large circular opening as well as other openings for fuel, etc. It is hardly compartmented.

Someone flying a plane towards the rear of the tank would have a clear path for projectiles into the engine block (and other internal components)save the screening element which is flimsy indeed.

A note on fuel cells:
Even diesal fuel cells can detonate when mostly empty. They form a stoichiometric mixture that explodes. A full diesal fuel cell is safer than an ampty one.

[Yoozername]

This picture shows the flaps up and the top access plate open.

[Yoozername]

The picture shows the access a mechanic would have if the rear plate and top access covers are removed.

[Yoozername]

From another thread...I would say its anectdotal but interesting. He claims something about plugs (spark plugs?). I thought diesels didn't need them. More than likely he is just rambling..

I can contribute something to the discussion on the T-34 engine.

Basically, it is very robust IMO incredibly so. The thing will run on about half cylinders, it will run for quite a while in extra-hot and extra cold weather without the appropriate support system (cooling fan, sufficient engine warmth) functioning. It will run when half the mounts are loose. It will run with a 5 cm. layer of mud on much of the underside, and all over the drive shaft. I have seen it run without a hitch at 35 centigrade above and 40 degrees below, although of course in the latter case the lubricants and fuel started out frozen, and the drivers had to melt the liquids by building a fire under the engine. But it worked fine, none of the tubes or cables caught fire, and the sucker cranked right up.

I have seen a ten ton steel girder dropped on that engine from about a five meter height, with nothing more than 20 gauge steel protecting the engine, and the only thing that happened was that some fuel, electric, and glow plug lines got torn off. They got reattached before the mechanics started it, but they told me it probably would have started even without that repair. No way of telling if that's true, but that's what the guys supposedly knowing all about the engine said.

In my opinion, a 20mm or 37mm round would certainly have the potential of hurting that engine if it hit it, but to my mind there would be a greater chance the thing would keep running, maybe less efficiently, but on the other hand it might well even shrug off the hit. We are talking about the engine the Soviets considered the best tank motor they every built.

(All of which could lead me to one of my pet peeves about CM which argues the Soviets are screwed because AP pentrations to a T-34 engine absolutely were less catastrophic than AP penetrations to typical panzer engine - but I will spare you.)

Anyway, these impressions are all from my personal experience - once upon a time I worked with an oil company in west Siberia, and some of the heavy trucks used by the firm were military surplus MAZ-437s originally designed for hauling SCUD missiles. The engine in that vehicle is the same as the T-34, unchanged after a half century.

The big problems with the engine from what I could see was that it required a lot of maintenance and fiddling, plug distance settings, filter cleaning, lubricant checks and top-offs, that kind of thing. A hands-off driver will kill that engine in no time flat.

Also I remember the engine had a tendency to rip itself free from the truck transmissions, but that wasn't the engine's fault, it was just developing a lot more torque than the MAZ engineers had designed their trucks to resist - the trucks were heavy, but naturally weighed nothing like a combat-loaded T-34 (That, and our drivers thought they were Mario Andretti and were running the trucks a good deal faster than MAZ thought they ever would go!)

I would add that diesel fuel isn't nearly as explosive as petrol. I have no idea to what degree, but to me, intiutively at least, an explosive round puncturing one of the exterior fuel tanks on a T-34 would be far from guaranteeing a detonation, and even if there had been I am far from convinced an explosion like that would have hurt the tank - after all, it was designed to resist explosions.

But that's just me speculating, I am sure there is some one reading this that can tell us in detail exactly how explosive Soviet wartime diesel fuel was and was not.

Looking at the T-34 drawings, it seems to me the Soviets had that engine protected quite well. This is not to say the tank was invulnerable to air cannon attack, but rather that the tank - in itself not a huge target - really doesn't offer a whole lot of super vulnerable bits to an engine deck pentration. Those grates aren't that big, after all, and if the AP round gets through the deck armor, bully for it but it's lost a lot of its energy.

If a round actually managed to strike full square on the "cylinder" heads, then sure that would mess up the engine - I guess it would just freeze 2-3 cylinders, leaving the rest of the engine either to clunk on, or maybe grind itself to bits. But there's no way to aim for that specifically, and those things are relatively tiny: maybe half a meter by 15 cm. Also, obviously, a pilot can't see them.

If an AP round made it through the engine deck armor my guess is that it would lose a good deal of pentrating power, and if it hit that big aluminum block it might well do nothing. It might also get a kill, of course, but "frail" is absolutely the very last word I would use to describe a T-34 engine.

I'm not trying to say the T-34 engine was as tough against air-fired AP as say a TigerII front was to ground-fired AP. But assuming all you need to do to hurt that engine, is to get a German round somehow to just touch it, is very wrong. You're going to have to hit that engine with some serious violence in a vulnerable spot. Hit it with less force, not particularly squarely, or just in the block, and I bet the thing would do an Everyready bunny.

[Panzer76]

While I commend your interest in this game and your posting on the finer details of AFV modeling, I think you will find it misplaced for such a relative simple game as PC. Seems more like you want a more detailed of CM, which I am sure we can all agree on, won't be this game.

[Yoozername]

I am only posting this as a means for entertainment. My own and others.

The assumption that I am posting this because I want it modeled is incorrect. If it IS applicable in some way, it might be abstracted in PC in a later game. A Super-Campaign type game for example.

I think CM was anally detailed in some aspects and simplistically detailed in other aspects. The net effect was a flawed product that was wrung out without any substantial improvement (besides the CMBO-CMBB iteration that attempted to fix the broken CMBO).

I see no reason why a well abstracted game can not be better than the flawed CM. I do not need details, I need the overall effect.

[Ursa MAior]

The block of the t34 engine was made of aluminium. One of the reasons the germans decided against a 1:1 copy.