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Hi Neil! Hi Folks!

- Neil_Baumgardner

- Roy_A_Lingle

When the developers started drawing up the Sherman tank, they were limited in how much it could weight. That limit came for the Combat Bridging Engineers M2 Treadway Pontoon bridge system.

<snip>That bridge could not have support the M-6 or T-23 heavy tanks. Notice the clearance between the treadway edges and the VVSS track block. Just a few inchs to spare on both sides. No room for a wider tank. No room for M4 with HVSS!

I'm sorry, but this sounds to me like putting the cart before the horse, or in this case the bridge before the tank... The bridge is designed to support the tank, the tank is designed to destroy infantry, fight tanks, etc, not to support the bridge. I understand this argument a little better when you're talking shipping, airlift or even rail-transport - for the first two at least you may have pretty big design constraints.

Designing the tank to fit the bridge seems a little backwards to me. Seems like if you decide you're going to have heavier tanks, you design bridges to handle said tanks - not decide you cant have heavier tanks because your current bridges cant handle them... Afterall, I would think its easier to design & build new heavier bridges than a heavier tank...

Sounds like putting the cart before the horse?
Designing the tank to fit the bridge seems a little backwards?

Yes!
If one JUMPS to the CONCLUSION that both were developed at the same time. There in lays the Catch-22. The M2 treadway bridge was developed and fielded years before anyone starting thinking about building something like the M3 Lees, little lone the Sherman. Don't forget, we where looking at the M3 Stuart with it's 37mm cannon as a main battle tank long before anyone started working on the M3 Lees. The original pontoon bridge system was more than enough for the M1,M2, and M3 family of light tanks.

The larger pontoons and sadles for the M2 treadways were designed about the same time as the Sherman because it exceed the safe rated level for that system. The larger elements were delayed do to the need for steel and rubber during the early start up period when everyone needed everything for their systems. That is why the weight had to fit the bridge system that was in service at that time. Fielding of HVSS vehicles and heavier Shermans was only possible because larger pontoon equipment was also in the works. At that point both systems were in sync.

More, I am sure later
Sgt, Scouts Out!

Hi Neil! Hi Folks!

- Neil_Baumgardner

- Roy_A_Lingle

I seam to remember of picture of T-23 crossing a Bailey Bridge. As so as I can find it, I will add it to this post.

That would be interesting...
Neil

Here you go Neil! Thanks again to Mr. Hunnicutt's Pershing book, page109.


The Bailey bridge was designed and field long before anyone though about building the Pershing. Caption with the photo: "This is one method of crossing a 60 ton Bailey bridge. The heavy timbers were used to protect the bridge curbs." This tight fit problem wasn't corrected until after the end of WW II. I sure most expericened tracked vehicle operators will look at that photo and cringe with the though of 'throwing a track' right in the middle of that. Then try doing a crossing like that under fire.

Note: Width of a T-23, T-23E1, T-23E2 and T-23E3 was 138 inches over the sandshields.
My guess is the sandshields only added an inch or so to the width.

Note: M-6A1 Heavy tank: Width over track armor 123 inches.
Combat loaded weight: 126,300 pounds (or 63 tons).
Looks like a M-6A1 would fit on a Bailey Bridge, but it would need more panels added to rise the load limit.

My 2 cents on the bridge problem.
Sgt, Scouts Out!

- Roy_A_Lingle

The Bailey bridge was designed and field long before anyone though about building the Pershing. Caption with the photo: "This is one method of crossing a 60 ton Bailey bridge. The heavy timbers were used to protect the bridge curbs." This tight fit problem wasn't corrected until after the end of WW II. I sure most expericened tracked vehicle operators will look at that photo and cringe with the though of 'throwing a track' right in the middle of that. Then try doing a crossing like that under fire.

Note: Width of a T-23, T-23E1, T-23E2 and T-23E3 was 138 inches over the sandshields.
My guess is the sandshields only added an inch or so to the width.

Note: M-6A1 Heavy tank: Width over track armor 123 inches.
Combat loaded weight: 126,300 pounds (or 63 tons).
Looks like a M-6A1 would fit on a Bailey Bridge, but it would need more panels added to rise the load limit.

My 2 cents on the bridge problem.
Sgt, Scouts Out!

Hi all,

As any engineer will tell you, the challenge isn't normally the dimensions of the vehicles crossing, it's the Load Class of the vehicle(s).

Bailey Bridges can easily handle up to MLC (Military Load Class) 100 crossings *if* they are constructed to handle that. MLC 30+ requires significant additional resources (panels, linkage sets, anchors, installation equipment/cranes, and much more time). It's not impossible, but to install such a bridge at every water crossing across Europe would rapidly strain the available bridging assets of the Allied armies.

Existing bridges in Europe at that time, even undamaged, were generally not designed to handle loads over MLC 20. This means that even capturing existing bridging intact was no guarantee that a heavy tank will be able to use it safely. (Some here may recall a large-scale effort to upgrade the German road bridge system in the 70's, to better support the growing weight of NATO AFVs.)

Just a little gas for the fire...

C

MLC = Military Load Class: For tracked vehicles, roughly the same as the overall weight in tons. For wheeled vehicles, the computation is more complex, and depends on the number of axles and tire size, among other factors. The MLC capacity of a bridge is based on the construction materials and structure of the the bridge, as well as the approaches and roadbed. Most not-modern bridges top out in the MLC 20-25 range, with higher MLCs usually requiring modern steel or concrete construction.

yes, i realize we are all civil here. i think remembering back to the old forum (no registering to post/reply) you had more folks commenting, many along the lines of what doug had mentioned (i just saw this or that on the boob tube). i think we are all pretty familar with everyone who is conversing on the forum now... so no blood, but you make a good point bob.
roy, glad you feel that way about the sherman now.
i agree with the 20/20 hindsight part...

there is a big difference between doctrine and reality... war distinquishes the two very quickly, "sorts" things out, defines them if you will.

there were various doctrines and armor philosophies, etc that were being formulated between the wars, many doctrines that unfortunately would dictate the way armies would fight the war. once the fighting starts, things evolve very rapidly, then you are stuck with doctrines that turn out to be a crock. the wargames the u.s. conducted in 39, 40 lead to the development of the TD force. (the u.s. didnt run into any enemy heavies until 1943-- tigers in tunisia, panthers at anzio). how do you change your doctrine, etc. etc. that quickly... one cant. the many facets that formulated and built the u.s. armored force up until that point of say 1944, how do you change it, improve it (whatever you want to call it), how do you do that and yet, still have it perform/function and continue to fight...
drive, drive, drive, go, go, go ...
i think that the americans and the brits had a fairly good combined arms philosophy going-- the sherman fit into that operation...
the tank is a piece of artillery (can be heatedly contested but i think that still holds true even today).
the ground work was laid, the game plan drawn up, within reason, before "first contact" was even made, before many debated thoughts and philosophies could be proven or disproven...
things never turn out how you would often hope.

- C_Sherman

Existing bridges in Europe at that time, even undamaged, were generally not designed to handle loads over MLC 20. This means that even capturing existing bridging intact was no guarantee that a heavy tank will be able to use it safely. (Some here may recall a large-scale effort to upgrade the German road bridge system in the 70's, to better support the growing weight of NATO AFVs.)

Just a little gas for the fire...

C

One reason why railroad bridges were so valuable. I know load limits are the critical factor in bridgeing but the problem I read about was a dimensional problem. Weight issues could be somewhat miticated by spacing out the heavy vehicles but if it's too wide, it's too wide the picture Roy found demonstrates that very well

Hi Folks!

This has been touched on some by others, but I would like to lay this out for the record.

The Sherman had two problems.

1. The Doctrine that was developed as the U.S. started ramping up for a globe war and sadly didn't change until after the war ended. The details of this problem will make a good size book.

2. Size and weight restictions that limited the early designs and as the war progressed delayed the fielding of better protected tanks with larger weapons. The technical problems cause their own sets of delays, but in many cases, I feel they were used to support the "Doctrine".

Neil and Bob have been looking at the problems with shipping. The limits of shipping was A problem that did delayed things, that is true. Could what was shipped been changed? Yes it could have had the need to support a different 'Doctrine'. But then again, look what happiened to the Pershings that were shipped to the PTO.

Sgt, Scouts Out!

The Sherman had two problems.

1. The Doctrine that was developed as the U.S. started ramping up for a globe war and sadly didn't change until after the war ended. The details of this problem will make a good size book.




the armored doctrines that the americans developed were very similar to the doctrines that the germans had pioneered and had been debated amongst the brits and french prior to the war. tanks werent meant to engage other tanks. thus they werent designed with anti-tank roles as there primary function. engaging and destroying armor was the role of the artillery, air support, and anti-tank guns. anti-tank guns (aka the tank destroyer) were developed to engage enemy armor, in the defensive posture, brought from the “reserve� or higher command elements, to the point(s) of enemy armor breakthrough. major general mcnair bore much of the responsibility for this way of thinking for the americans. only time would tell, if this american use of armor was effective. unfortunately, the americans entered the war late, had a retarded tank program, one which lagged way behind the germans, russians and brits. time and combat experience were against the americans.
all nations included, it was just a matter of time before folks had to realize that the more armor units start running across the battlefield, sooner or later they eventually would have to face each other. the germans and the russians learned this very quickly. americans didnt learn this until 1943/44 (too late, u.s. industry already producing according to the parameters set down in 1941/42).

one of us had brought up the idea of why the americans hadnt been a little quicker to design a heavy (or heavier) tank early than it had. it wasnt part of the armored doctrine at the time. tanks were to be fast and exploit, heavy doesnt fit this parameter. besides the french and british and the russians, no one had heavy tanks prior to 1942.
heavy tanks werent an element found in the blitzkrieg principles. the blitzkrieg had defeated the french and british heavy armor in 1940, and was well on it way to defeating the russian heavy armor in 1941. the americans had no real urgency to design and field a heavy tank. ** how can you change what you dont know to be broken yet. **

2. Size and weight restictions that limited the early designs and as the war progressed delayed the fielding of better protected tanks with larger weapons. The technical problems cause their own sets of delays, but in many cases, I feel they were used to support the "Doctrine".

yes, i agree roy, but i wouldnt use the phrase “support the doctrine�, more like fit the parameters laid out by the doctrine. size and weight restrictions meet the requirement of tanks that are mobile and can breakthrough and exploit the enemy. those restrictions were acquiring to the armored doctrine that the americans had adopted for its armored force. restrictions that werent necessarily determined by shipping, logistical support and the like. the pershing was well armored, well armed, and had adequate speed (could exploit and support�the role of the tank). armored warfare had evolved and had dictated that tanks will eventually have to engage AND defeat other tanks while still falling under the qualifications of being a tank and not a tank destroyer. the pershing met these qualifications, and for 1942 the sherman had met these qualifications.

anyway, never thought i would show favor for the russians but they were the only ones to really design heavy armor and with reasonable adequacy be able to support and sustain that heavy armor in the field effectively. they had many logistical problems but they didnt suffer such as the germans as to have that heavy armor be more of a detriment.

Hi Folks!

A Techical Point - The Pershing was needed because it had better protection.

Look at the following three photos and asked yourselfs if that is correct.

From an article in the old Journal of Military Ordnance titled "What's Wrong With the T26E3?" dated July 2002. Vehicle is Nu 25, Reg. Nu. 30119835, March 6, 1945. Vehicle was hit by a 75 or 88 mm round which went through the front under slope, started a secondary ammo fire which burned out the turret area. "Amazingly, the crew surivived unharmend."



This photo comes from Hunnicutt's Pershing book, page 18. Vehicle nu. 38, Reg. Nu. 30119848, vehicle name "Fireball", Feb 26, 1945. Hit three times by a Tiger I, first round hit near the coaxial machine gun port, entering the turret and killing the loader and gunner. The second and third rounds hit, but didn't penetrate. One destoryed the 90mm gun barrel which had to be replaced. Vehicle was repaired and returned to service by March 7th 1945.



This photo also comes from Hunnicutt's Pershing, page 192. The vehicle IS a M46 that was destoryed by a 85mm round from a T-34 during the Korean War. This photo still support my point because the T-23E3 and the M-46 both had the same front hulls and the Soviet 85mm round is between the German 75s and 88mm rounds.



If the front of a T-23E3 had better protection than the Shermans tanks, why did the 3rd Armored Division, cut up a Panther hull and weld parts of it onto a Pershing tank? Could it be, they had learned that the front of a Pershing wasn't any better than the Sherman is was replacing?

Was the T-23E3 with it's heavier armored really needed? Did shipping schedules need to be changed just so wider and heavier tanks could be sent?

Technical Point - more armor.
Sgt, Scouts Out!

I think the 3 AD attempt at a Super Pershing was an ordnance maintenance shop gone wild. Get any group of GI's who have the tools and the time and they love to modify equipment to make it 'better'.

So they get a new test Pershing with the new 'super' 90mm (It was even more powerful than the 90mm used in the regular Pershing) and they decide to modify the tank so it can go out 'Tiger Hunting' Extra armor, extra hydraulic cylinders to help move the heavier gun barrel with the extra armor, etc. It all probably defeated the purpose of getting a test tank out to the field in the first place. (Of course the fact that the supply system misplaced the ammunition for the new gun so they couldn't actually use it for several weeks didn't help.)

Roy brings up a good point about the first Pershings sent to Europe. It's been a while since I looked at the summary of what happened to them that is in the Hunnicutt book but I remember being surprised at how badly they got shot up in ashort period of time

The problem with the 90mm armed Sherman was breaking the 90s loose from Air Defence from what I understand. We might have had a better tank than the Pershing ealrier but they apparently tried to get too advanced and the army didn't like the support requirements. My impression is that we could have had 90mm armed Shermans by the summer of 44 if the army (and its various components) thought it was necessary. But you are dealing here with at least 4 major beurocratic organizations and probably more. If the user had stated clearly and loudly it was needed then it could have been accomplished and fairly quickly but there was no loud united voice to that regard until after D-Day.

I thought the occurance of Tigers in Africa was so rare that few conidered it a serious problem (short sighted I know but ....)

oh i agree whole heartedly roy. armored protection was the key, more armor indeed! it hurts to say, cause i are one, but we americans fell way behind in tank design and production, and we paid the price. we came out on top but it cost us. i think that the american automotive industry and all involved, given more time, addressing the issues sooner (hindsight again), could have designed or initiated a tank program much earlier than we had. the russians and the germans beat us, they got started in the arms race much sooner, but still they had us beat when it came to dealing with the armor protection dilema.
not all they did was successful, but they were addressing the problem. doesnt mean i feel they designed and built better tanks, they were just working on solutions.

i am going to quote an author here, makes a very good point, would apply to the Pershings as well as the Shermans:
"Perhaps the wonder is not that the M4 succeeded in spite of its early problems, but that, given the restrictions imposed by circumstances, it was as good as it was. At the time of its first service evaluations in early 1942, the M4 Sherman was easily one of the best all-around tanks in the world."

the arms race escalated very quickly and america fell even further behind.
at least i give the americans credit for at least showing the insight to be albe to design, initiate and implement "weapon systems", if you will, that they knew and understood that they had to support, that they could field. americans, didnt go ape and try to make all of these crazy super weapons and behemoths that werent practical for the circumstances at hand. no comments on that tortoise thingy. to reverse that logic, many of what the germans fielded, way to early, could they have saved more of their lives by not being so hasty? if time was of the essance, they couldnt afford it, that is a good pro for the sherman and american industry. america could continue to produce, make efforts for improvement, without distrupting the flow of production. we didnt stop, as the enemy, and start over from the ground up everytime with all of the new design, r&d, etc. to make a new tank. for the idea of designing a tank that could be produced at roughly 2000 a month, the americans were on their way to doing so. considering all of the changes and modifications that evolved during that production, the u.s. did very well. anyway...

Another thought is that designing a tank to be the best one on one is not necessarily the best way to design the tank that is best for the army. More armor means a lot more weight at that time and more resouces. While haveing a vehicle with the armor and weapons of a Sherman may have cost the US tankers more casualties (even that is not necessarily true) it probably saved US lives overall. The numbers of tanks that could be manufactured, transported, crewed, and supported meant that when the US needed a tank not only could one usually be found but there was a good chance that several could. This meant a lot of support for the infantry and it mde it easier to mass for breakouts and sustain said breakouts. I maintain that from the US Armies point of view there probably was no better tank that fought in WWII. Now a Sherman with a 90mm gun in 44 would have been better but that's a definite what if. Another thing about armor as I recall someone posted on the old board (or perhaps it was tank net) that the main complaint of US tankers wasn't the armor it was not having a big enough gun.

Bob Smart wrote:

"They used...American AP that had the explosive filler removed (I assume they were delivered with the cavity empty and that they did notactually remove the explosive charge that the Americans designed the rounds for). "

Many years ago a WWII/Sherman vet told me they were really happy when their 75 mm Shermans were replaced with 3" navy gunned Shermans (his choice of words). I presume what he called 3" navy guns were the 76 mm gun.

He said they liked them because you could add "gunpowder" to the shell. I never fully understood what he meant by that, but his words stayed with me. After reading Bob Smart's comment, I'd guess they were talking about the same thing.

Comments?

- Skeet

Bob Smart wrote:

"They used...American AP that had the explosive filler removed (I assume they were delivered with the cavity empty and that they did notactually remove the explosive charge that the Americans designed the rounds for). "

Many years ago a WWII/Sherman vet told me they were really happy when their 75 mm Shermans were replaced with 3" navy gunned Shermans (his choice of words). I presume what he called 3" navy guns were the 76 mm gun.

He said they liked them because you could add "gunpowder" to the shell. I never fully understood what he meant by that, but his words stayed with me. After reading Bob Smart's comment, I'd guess they were talking about the same thing.

Comments?

Was this an American, British, or other Vet?

The Americans had an explosive filler in some of their AP rounds, other ones were solid. As I understand it once the APHE became standard the British did not want the filler in the round.

I don't know of any 76mm gun Shermans being issued to British units (Like the GAA engined M4A3 the U.S. tended to keep the 76mm Shermans for themselves, but 76mm gunned M4A2s were sent to the Soviets)

We had a discussion on the old board about the 'navy 3" gun'. I think this is one of those cases where word of mouth got it wrong but it became perpetuated and won't die. The M10 was equiped with an Army 3" (started life as an AA gun). I beleive the 76mm in the Sherman and the 3" used the same round. There were differences in the gun itself though.

This was a U.S. Army vet. I suspect that the grunts on the ground use words that weren't exactly true, but served their purposes.

This same vet used to talk about the German 88's. A lot of what he spoke about seemed to indicate they could have been 88's. But a lot of what he said made me wonder how (why?) the German's could be using 88's like that, i.e. indirect fire into camps/parks on reverse slopes. I posted that question a while back, and the consenus was that lot's of WWII vets from the ETO referred to all German artillery as 88's.