For discussion

[Simon Daymond]

I took the militant to Keighley yesterday as part of a display organised by the town council for a veterans display.

 

As it was hot, we retired to the local pub, where I had the real privelage of talking to a couple of veterans, both well into their 80's.

 

one used to serve on Dukws amongst other things, the other was a gunner and wireless operator in Chuchill tanks.

 

As usual, they were slow to speak about what they'd done, no doubt not aware that everything they said was fascinating.

 

To the point,

 

they raised a couple of interesting ideas, which I know we all could pass a bit of time chewing the fat over

 

First item : jerry cans, the British used to use 2 gallon tins, but after being used a couple of times they used to leak badly, so after the desert campaign, they started to use discarded German cans, and the British then had replicas made in Egypt?

 

Second item: the reason our tanks were so small compared to those of the Germans, was due to the railways? The fact that our tracks were so near ( up and down lines) meant that there was a smaller width available when transporting the tanks by rail, something that the Germans didn't suffer with as there lines were further apart?

 

Final point: Tank crews, I didn't realise that the crew on a British tank had to operate it and carry out repairs & servicing, whereas our American counterparts had a crew to 'fight' in with tank, and completely seperate crew to repair and maintain it. The guy gave an example where once he was in a Sherman with an American driver, he asked the driver about certain parts and controls of the tank, and the reply was ' I don't know - I only drive' !

 

Anyway just a bit of something to give you something to post about, not saying any of the above is true, or not, but interesting to know a little more about it.

[steveo578]

N.O.S.

I guess nobody could develop a side - loading breech due to the forces generated within the barrel, but it would have made the gun so much more compact.

 

 

During WW2 several designs were developed to prototype stage by having a none-recoiling mount which in a tank requires a very strong turret ring to absorb the shock, There is an example in Sherman by Hunnicut using the prototype for the T72 (M10 development) with a fixed (none recoiling) 75mm M3 gun the study was not fault free but as a test the ordnance were quite satisfied.

 

The Germans trialed StuGs-PzJg with none recoil guns -which had the advantage that without a turret ring absorbing the shock was easier- it did not lead to service vehicles but was tested in Hetzer 38(t)* and a PzJg 4 was also tested.

 

Post war soft recoil systems have been used in light vehicles and numerous other trials took place to improve turret ergonomics -one trial was for a liquid propelant which made the combination cartridge and shell obsolete -but lead to other problems. Of course the Chieftain reverted to shell and bag charge system with some success.

 

Steve

Edited October 29, 2010 by steveo578
error number T70 changed to T72 -T70 is a M18 hellcat

[Sean N]

Second item: the reason our tanks were so small compared to those of the Germans, was due to the railways? The fact that our tracks were so near ... meant that there was a smaller width available...

 

Is this really true though? Up to Pz IV the German tanks were pretty small as well - Pz IV is only 9' or so wide. Tiger 1 and Panther are wider than, say, Churchill or Comet, but not by all that much; I suppose there's a big difference between Cromwell and Tiger 1, but a Churchill is only a few inches narrower than a Panther. Centurion - OK, not WW2, but designed at the time and presumably under the same constraints - is near enough the same width as Pz V.

 

I always had the impression that the differences, and particularly Tiger II and the real German monsters of the later war years - had more to do with design philosophy and perceived use (and possibly megalomania!).

 

And what about Tortoise...?

[steveo578]

Sean N

Is this really true though? Up to Pz IV the German tanks were pretty small as well

reasonable point, as you say upto and including Panzer 4 german tanks were quite small and narrow- oddly enough the more advanced and marginally wider Pz3 because of its box structure was incapable of upgunning to 7.5cm L48 and Hitler, the technical expert that he was, declared it a failed design. The Panther at 11ft 3in was pushing the beyond the loading gauge but until the Cent. arrived none of the British tanks came anywhere near the width of the Panther, Cromwell 9ft 6in Comet 10ft Churchill in travelling mode -without the air intakes 9ft. (10ft 8in with intakes) so both nationalities were effectively using the same rail width constraints.

 

The real problem with the Tiger was the rather clumsy re-tracking of the tank for rail transport Had the constrainst of VK3601 been maintained the Tiger would have been 40ton and 10ft 4in wide a far more practical proposition -probably there would have been more produced and earlier too. As you said megalomania had alot to do with it, it's debatable whether design philosophy and perceived use is really relevant as all the Cats were designed to attack but were in actuality used as defensive weapons- they lacked the elan capability.

 

Tortoise -an aberation -a case of they have super tanks SPGs we've got to have one.

 

Steve

[Pzkpfw-e]

German rail guage and ours are identical, hence the Tiger having transport tracks as shown in the one preserved in Saumur.

Compared to the similar late-production model at Vimoutiers.

The tracks were changed and the outer set of road wheels and the track guards removed prior to loading on the special rail cars. The road wheels can be seen stacked behind the tanks in this photo.

The combat tracks being stored doubled-up, under the tanks.

The tank was nearly 2ft wider with its combat tracks fitted.

Width with combat tracks3.72m (12.2 ft)Width with transport tracks 3.14m (10.3 ft)

[Shamouti Ben Yafo]

All very true; but a boxy hull to fit the Broad Gauge would, of course, still have had a wider turret ring...

 

The T shaped hull would have indeed been the correct solution, though, since there was no hope of widening the loading gauge. Which were (plural!) narrower than German (continental) gauge, except on the ex-Great Central.

 

Side-loading breeches - didn't the Hetzer have one?

[steveo578]

Shamouti Ben Yafo

..... but a boxy hull to fit the Broad Gauge would, of course, still have had a wider turret ring...

 

The T shaped hull would have indeed been the correct solution, though, since there was no hope of widening the loading gauge. Which were (plural!) narrower than German (continental) gauge, except on the ex-Great Central.

 

Continental loading guage (which became the Bearn Loading guage) still ran on 4ft 8.25in only the Russian/Soviet rail guage was larger at 5ft 2in, the problem for the British rail system is avoiding making a tank shaped hole:nut: in every track side accessory and tunnel in the path of a Rectank carrier and its locomotive- the point is this old chesnut has rolled around long enough British tank designers were ***** ***** (add your own favourite expletive) and should not be allowed to hide behind excuses- the only response to why did british tank designers fail to come up with a decent tank in WW2 is that old Army response "No excuse sir"

 

Side-loading breeches - didn't the Hetzer have one?

I think you mis interpreted the point N.O.S. made -if the pressure chamber was at 90° to the barrel -it could be done but it would be too complex and reduce the loading rate. an example of a weapon that had multiple pressure chambers at an angle to the main tube was the 15cm Hochdruckpumpe which was a German "super gun" of WW2.

 

The Hetzer's gun was a standard 7.5cm Pak 39 which had a sliding breach block.

 

Steve

Edited October 31, 2010 by steveo578
spelling

[Shamouti Ben Yafo]

Gun - Ah; I see!

 

Loading gauge - the figure you quote is the rail gauge; loading gauge takes into account all the infrastructure - bridge dimensions, platforms, distance between roads/tracks. This is why each company had its own, even though the rail gauge was standard throughout by the late 19th Century.

 

But yes, no excuse - lack of imagination, apathy, laziness; who knows?

 

Impressive as the German heavies were, though, could they get them to perform with the necessary reliability?

 

The answer to that is one reason why we don't have to say "Vorsprung durch Technik"!

[steveo578]

Shamouti Ben Yafo

Loading gauge - the figure you quote is the rail gauge; loading gauge takes into account all the infrastructure - bridge dimensions, platforms, distance between roads/tracks.

 

Yep that's why they have that quadrant shaped bar thingy at every marshaling yard:D and why earlier in the thread there is a photo of a Cent. being presented to a plywood gauge.

 

Impressive as the German heavies were, though, could they get them to perform with the necessary reliability?

 

As many members will attest I don't go much on - Vorsprung durch Technik but to be fair from the very limited reports of their use in the Ardennes battle , both the kurze 15cm Hochdruckpumpe performed effectively -the rail mounted one bombarding Antwerp (at quite some distance) and the fixed unit on a hillside at Hermeskeil was used to bombard targets in luxemburg -but even a "mobile" rail mounted unit was fairly immobile in the winter of '44-45 so both were destroyed by their crews. information on both these weapons is very limited -at the moment I can't even find the number of supplementary chambers used.

 

It would seem the two mentioned as firing during B of B were 2 fixed instalations firing on the city of Luxemburg which had been in American hands since september they fired over 180 shells at a range of 43km -dispersion was fairly large only 40 could be said to be "on target" and very few colateral losses were evident- however like the Paris gun of an earlier era the fact that a gun could bombard a city at 40km was sufficient to cause consternation- it's like being under a sniper, it's not the number of people killed but the disruption caused by the loss of free movement. These guns were about 50metres long and had 12 pairs of supplementary chambers.

 

The Rail mounted HDPs don't seem to have been used -although some sources said they were used against Antwerp- it would seem that the "15cm shells" that landed in Antwerp were probably RheinBote which had been bombarding the city off and on since November -a Rheinbote was a multi-stage rocket range 78km but only had a 40kg warhead. The rail mounted weapons were handed in to the main artillery depot and the crews moved out with more practical weapons.

 

Generally under-rated by authors -it has to be remembered that a major casualty of the HDP was Joseph Kennedy Jnr the older brother of the later President John Kennedy. Joe jnr was killed when his plane prematurely exploded during an attempt to radio control aim a munition loaded PBY1 -B24 onto the main HDP site in the Pas de Callais.

 

Steve

Edited November 2, 2010 by steveo578
additional research in italics