Fully tracked APCs for ww2: not worth it; or, why they didn't think of those?

[tomo pauk]

...I'm thinking about the vehicles that should provide a protection, for the mounted infantry, from artillery shrapnels and LMG fire. Sporting also roof armor to protect from light mortar fire, hand grenades, fire from the windows of the high buildings etc. The APC would be something along the lines of M-113, other technicalities shared with the AFVs/tanks from the era.

What's your take?

 

[pbfoot]

the Kangaroo although lacking in the overhead armour certainly must count as an APC
http://en.wikipedia.org/wiki/Kangaroo_(armoured_personnel_carrier)

 

[davebender]

Full track has nothing to do with overhead armor. It's about how much of the vehicle weight is carried by tracks vs how much weight is carried by the front tires on a half track. Carrying all or most of the weight on tracks increases cross country mobility.

 

[Shortround6]

Bren carriers?

No overhead protection though.

Most nations had enough trouble trying to make enough tanks.

making full track APCs is not that easy. While the armor is thinner you still need the tracks, suspension, transmission/steering gear.

Even M-113s were never intended to be used IN the battle but to get the infantry TO the battle.

 

[davebender]

I disagree. Making full track APCs is no more difficult then making full track tanks or SP artillery. The issue is resource allocation.

A single German mechanized infantry company requires a minimum of 12 APCs.
3 companies per battalion.
9 battalions per division.
.....Add APCs for support elements (SP flak, SP signal, SP mortars, armored ambulance etc.) and you need 400 to fully mechanize an infantry divsion.

100 mechanized infantry divsions require 40,000 APCs @ 22,000 RM each (for Sd.Kfz.251) and a whole lot of fuel (plus fuel trucks). Full track might bump the price up to 30,000 RM per APC but that makes little difference. Nobody can afford to mechanize this many infantry divisions and keep them supplied with fuel.

 

[Glider]

This brings a question re the M3 halftrack. Did it bring the benefits of both types of traction or did it bring the worst parts of both? Having gone to the cost of building it why didn't they extend the tracks and get rid of the wheels.

Any ideas?

 

[Shortround6]

Mr Bender is correct, the "Making full track APCs is no more difficult then making full track tanks or SP artillery. The issue is resource allocation. "

The point was that full tracked APCs are not going to be much cheaper or easier to make than a tank or SP gun of similar weight and if you can't make enough of them then APCs are going to be hard to come by.

Mr. Bender also as a point about fuel. Full tracked vehicles, as a general rule of thumb, have twice the rolling resistance of a wheeled vehicle which means for a given weight the tracked vehicle will need twice the fuel to go the same distance at the same speed. Given WW II technology, track life is also fairly short. 3000 miles on a set of tracks was considered almost miraculous. Some tanks went through tracks in as little as 600 miles. Full tracked APCs offered tactical mobility but came up short in strategic or grand tactical mobility.

The American Half track used a rubber band track, no links, just a big rubber band with steel cables inside. It did offer lower ground pressure than a wheeled vehicle but trying to extend the size of the tracks/bands may have been a problem. As would trying to steer with them.

I have no experience with them but I used to drive a 68,000lb fire truck with three axles, the rear two powered, it chewed the rear-most axle tires up some fierce, under 8,000 miles. Lots of city driving and sharp corners. I would imagine trying to use rubber band tracks to generate the turning motion driving them at different speeds and scrubbing as they turned would chew up the tracks. Granted this is not an issue for off road use but how much of the APCs life would be spent on roads?

 

[Juha]

This brings a question re the M3 halftrack. Did it bring the benefits of both types of traction or did it bring the worst parts of both? Having gone to the cost of building it why didn't they extend the tracks and get rid of the wheels.

Any ideas?

M3 was more like 4x4 armoured truck with rear wheels substituted by a track system, fairly cheap system, German armoured h/ts were in essence fully tracked vehicles with longer forward body under which there were unpowered steerable front wheels with the complications and expenses of fully tracked vehicle but better ground loading than M3. IIRC SdKfz 250s/251s used system where gentle curves were handled with the steerable front wheels but any steeper curves needed normal fully tracked vehicle steering which meant complicated and costly steering mechanism.

Juha

 

[Glider]

Thank you both, I have often wondered about that

 

[Denniss]

If my memory serves right the german halftracks used truck chassis as well. but they may have modified them more than other countries.
Halftracks were not only built because they were comparable cheap, they could also use truck chassis manufacturers to produce tracked vehicles, no need to bother tank manufacturers with another task.

 

[tomo pauk]

Thanks for the inputs

Some questions:
How good were the half-tracks in following the tanks, off road?
Would it been better to have infantry traveling inside an APC, or as a tank-riders?
How frugal was building using the M3/M5 lights in 1943/44, 2 pdr tanks in 1942-43, 6pdr tanks in 1944, Pz-38(t) in 1942?
Ditto for Centaur, Valiant, Covenanter?
What was the cost of the Universal Carrier?
What happened with the tooling for the Vickers light tanks?
Weren't the light tanks mostly built away from dedicated tank factories?

 

[GrauGeist]

The Germans used a light Soviet tank chassis to modify the Opel truck and as a result, the Maultier half-track proved to be for more reliable over open/rugged terrain than the original all-wheeled configuration...

 

[pbfoot]

I m3ntioned the Kangaroo earlier was it the 1st tracked APC as we know it today it is fully tracked and found to be very useful although of a relatively short career from Falaise to VE day
here is the Wiki blurb on the Regiment which was the only regiment formed overseas in WW2
1st Canadian Armoured Carrier Regiment - Wikipedia, the free encyclopedia

 

[GrauGeist]

That Kangaroo was the M7 Priest, wasn't it?

 

[pbfoot]

That Kangaroo was the M7 Priest, wasn't it?

one version

 

[tomo pauk]

pbfoot, I'm fully aware of the Kangaroos. An army being awash with Carriers, decided to use an redundant tank/SPG hull (= more horizontal protection) - that might point that a heavy APC had it's place at the battlefield. Sure enough, a LMG- and splinter-proof (light) APC would be fine for an army trying to adopt a really combined arms layout?

GG, there were Ram- and Priest kangaroos, depending upon the AFV that was converted. There was also a Churchill Kangaroo (prototype?).
What I'd like to see is the Grant Kangaroo (unless making a dedicated APC), converted from the early versions sporting the side doors, LMG turret, steel sheet covering the roof (37mm turret deleted, along with 75mm, it's former position receiving an armor sheet).

 

[Shortround6]

Thanks for the inputs

Some questions:
How good were the half-tracks in following the tanks, off road?
Would it been better to have infantry traveling inside an APC, or as a tank-riders?
How frugal was building using the M3/M5 lights in 1943/44, 2 pdr tanks in 1942-43, 6pdr tanks in 1944, Pz-38(t) in 1942?
Ditto for Centaur, Valiant, Covenanter?
What was the cost of the Universal Carrier?
What happened with the tooling for the Vickers light tanks?
Weren't the light tanks mostly built away from dedicated tank factories?

The medium tanks were too heavy to make really good APCs but they were available. Light tanks (of the WW II variety) make lousy APCs because they are too small. An APC needs to hold a normal squad or close to it. Using two or even three vehicles to move 10-12 infantry men is not only wasteful but gets really confusing at dismount time.

Extending the hull on some tanks can be done but only works so much. If the length of track on the ground exceeds the distance between the tracks by more than about a 1.8:1 ratio the vehicle becomes hard to steer.

Converted tanks are less than ideal because the rear engines mean the infantry have to dismount and mount over the sides. It was done but it is certainly less than ideal and causes injuries.

The Half tracks could keep up pretty well and tank riders are a really bad idea. Better than no infantry but carrying your infantry on surfaces that bullets and shell fragments can ricochet from may actually increase casualties. The Russians may have accepted such casualties but the western nations would not. Please note there is a big difference between giving infantry a ride up to the front or in rear areas and carrying them into gunfire on the tanks.

The continued production of some light tanks (in fact a lot of them) was a waste of resources. But an armored division only had about 100-300 tanks depending on army and time. You need at least 45-50 APCs for even a small Battalion of 3 companies each with 3 platoons allowing for headquarters units and such.

It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.

 

[GrauGeist]

...It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.

And air support!

 

[tomo pauk]

Good call, GG. One still need artillery as a ground pounder, every bit.

The medium tanks were too heavy to make really good APCs but they were available. Light tanks (of the WW II variety) make lousy APCs because they are too small. An APC needs to hold a normal squad or close to it. Using two or even three vehicles to move 10-12 infantry men is not only wasteful but gets really confusing at dismount time.

Maybe you're misuderstood my mentioning of all the tanks in the above post - I'm not saying that those were to be converted into APCs (not my 1st call anyway), but to point into the fact that some armies were awash in tanks, yet had (almost) none of well protected APCs that might carry infantry to within hundreds of meters close to the front line. Under 'well protected', I assume that a gun equal to 50mm or better was needed to tackle those.
Regarding to the number of vehicles to carry a squad, the U. Carrier carried 5 crew, driver included. Falls well within the 'lousy APCs' group?

Extending the hull on some tanks can be done but only works so much. If the length of track on the ground exceeds the distance between the tracks by more than about a 1.8:1 ratio the vehicle becomes hard to steer.

Guess you're right about the ratio. The Cromwell -> Challenger conversion was noted as not as maneuverable as the Cromwell itself.

Converted tanks are less than ideal because the rear engines mean the infantry have to dismount and mount over the sides. It was done but it is certainly less than ideal and causes injuries.

Agreed 100%. That's why I'm talking about a 'classic' APC as a better solution.

The Half tracks could keep up pretty well and tank riders are a really bad idea. Better than no infantry but carrying your infantry on surfaces that bullets and shell fragments can ricochet from may actually increase casualties. The Russians may have accepted such casualties but the western nations would not. Please note there is a big difference between giving infantry a ride up to the front or in rear areas and carrying them into gunfire on the tanks.

When mentioning the tank riders, I'm trying to point out that an APC would be also good for Soviets in ww2. Despite all the saying about the USSR as having plenty of manpower, saving thousands of infantryman (that can grow some experience, instead being mowed down by the mortar, artillery MG fire) seems like a good thing.

The continued production of some light tanks (in fact a lot of them) was a waste of resources. But an armored division only had about 100-300 tanks depending on army and time. You need at least 45-50 APCs for even a small Battalion of 3 companies each with 3 platoons allowing for headquarters units and such.

All fine, we better start producing the APCs ASAP - if the infantry in the units mentioned are to be riding at the Carrier, the number of vehicles required skyrockets

It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.

SP tracked artillery was present in major armies. Plus, many of them towed their guns by half tracks or fully tracked vehicles; such arty did not needed to close within hundred of meters to the enemy. The APC needed to closely follow the tanks or assault artillery were not that present, though.

 

[davebender]

M3 was more like 4x4 armoured truck with rear wheels substituted by a track system, fairly cheap system, German armoured h/ts were in essence fully tracked vehicles with longer forward body under which there were unpowered steerable front

I agree. The difference is obvious if you look at vehicle pictures.

Sd.Kfz.251 3/4 Track.

Track suspension carries most of vehicle weight and it's the same state of the art schachtellaufwerk suspension employed on Panther and Tiger tanks. Consequently troops and equipment in back have a relatively soft ride when moving cross country. Protective armor is nicely angled too. Vehicle may be steered using tracks. That's important for a combat vehicle as one or more front tires are likely to be shot out when bullets start flying. Amazingly enough this superior WWII era APC was also slightly less expensive then the U.S. made M3 Half track.





M3 Half Track.

Small track area in contact with ground made it essential to power the front wheels to obtain cross country mobility. However you were screwed if the front tires got shot out. Ride and armor protection were inferior to German made counterparts.