3in and 3.7in "CS tank" howitzers

I've always said that when it came to the British Army's armour doctrine pre- and immediately pre-war...they put YEARS of experimenting 1927-1931/32 into it - but when the war eventually began it turned out that the pesky Hun didn't use the same rulebook!

REALLY unsporting of them!

That's something that would be VERY interesting to find out - exactly what field expedients or theatre changes were made to the doctrine

 

Yes....but in the case of the RAC (and later the tank brigades) they started the war with the primary CS role....by a long chalk...being throwing smoke. Later it was leavened to an extent with H.E. in SOME tanks...but seems to have remained primarily smoke in "CS" tanks...

Was this the American experience of "Close Support", or were they mostly used to fire H.E.?

 

Didn't? Or by this period couldn't? I note the paragraph dealing with how 7th Armd Div's Italian experiences governed their behaviour that day...I wonder how their CS capability looked by 1944 compared with 1943 and earlier?

In the last paragraph it certainly looks as if it's couldn't...

Phyllo,

You have seem to have a knack of plucking at the twigs that support your line of interest and ignoring the remainder of the forest!

This is a post war interview with General Hobart. There is a mountain of data about Op Goodwood and Hobart's recollections of his meetings with O Connor is just one element.

Yes Tanks could produce smoke, which might help the leading troop extricate itself if in difficulties or even support a squadron attack on an isolated enemy. However, armoured units lacked the logistics to make smoke screens that could make a difference in a Corps or army level battle. The attack by VIII Corps on I SS Corps took place over a 100+ sq Km plain dotted with villages which formed the basis of anti tank positions. The depth of the German position meant that the battle for the villages south of the EW railway line were beyond the range of allied artillery - hence the use of heavy bombers. By the time the armour reached villages such as CVagny the defenders had recovered from the effects of the bombing. The British armour tried to penetrate between the villages but lacked enough integral APC mounted infantry to clear the villages quickly and a day long battle took place.

The idea of a smoke screen is to put a screen between an area to be blinded and an area to be screened. If the area to be blinded and the areas to be screened are both small, then it is quite easy to work out where a few smoke rounds could be effective - once an allowance has been made for wind speed and direction.

If however either of these is big then a screen would need to be built up on carefully calculated points on a line between the areas to be screened and blinded. Each firign gun will need to be given a different r=target. This is not a drill practiced by RAC units. Even calculating the points of origin for a linear smoke screen needs three assets not found in an armoured Regiment in a mobile battle. 1) Technical staff adept at calculating smoke screens. 2) A table somewhere quiet to work. . .

In the case of Op Good wood the areas tpo be blinded might be "the village of Cagny and surrounding fields a 250 x 250m area" and the area to be screened might be "All parts of a 3 km route from the North and round to the West of Cagny". This might be a linear screen at least a 1 km long.

Armpured Regiments lacked the level of logistic support to maintain a tactically useful smoke screen. The hypothetical; 1 km smoke screen blinding the village of Cagny would require between 6 and 12 guns firing for the duration of the screen. The WP smoke round available to CS tanks is roughly comparable to that of the 81mm Mortar and the standard rate of fire for this kind of smoke screen is five rounds to .build upo the screen followed by four rounds a minute. This would require 54-108 rounds for the first minute and a further 24-48 rounds per minute subsequently. So an hour's smoke screen would need C. 1500 -3000 smoke rounds - consuming the entire ammunition for 15-30 tanks. This is a non starter and why the significant smopke screens were left to the artillery, whose guns, served by the RASC fired huge amounts of ammunitioon.

 

Yes??? Because I'm not actually interested in GOODWOOD - I'm interested in tanks throwing smoke and its tactical use by them. Why wouldn't I be picking up on the bits that interest me? Such as Hobart's "and after that the tanks themselves were often too easily held up by a few odd German tanks which they might well have blinded" remark...which reads like a failure on their part, not the RA.

 

The point being made is that there is a huge difference between a troop of tks firing smoke to blind a bothersome position for a few minutes to enable a few other tanks to extricate or whatever themselves and the large scale use of smoke to screen a large attacking force over a large area for an extended period. Smoke is merely a form of suppression in that it prevents/reduces the effectiveness of the enemy doing what they want/should be doing. HE also does this, but smoke is a bit more suitable if you are not entirely sure where the enemy are.

Other things being equal it may have been quicker for CS tks than arty to fire smk in the first case, but it would depend on the detail of the situation, notably the exposure of the CS to en direct fire and the ability of the CS tanks to see exactly where to aim their fire. If either of these were problematic and the local arty troop comd could see the area then a troop target smk would probably have been a better solution to the tactical problem.

 

That's close to what I was thinking: HE also does this, but smoke is a bit more suitable if you are not entirely sure you can hit the target.

Was the RTC's original intent to use HE for close support but, given the poor accuracy of their CS systems, they switched to smoke where a reasonable chance of inconveniencing the enemy was better than a negligible chance of hitting him?

 

Hobarts comments are extremely uninformed and unsupported by other evidence. If you visit the ground and study the dispositions as whole generations of British Officers have done post war,(1) or even read a book por two on the subject you would realise what utter rot Hobart was talking. There were not " a few isolated tanks that could be screen. The Village of Cagny contained SP guns and famously an 88mm AA gun battery this dominated a killing area to its NW. The same area was engaged by the Tiger II tanks of 503 Heavy tank battalion form a position 2.5 km to the .NE of Cagny. British armour in the killing area was engaged on a 135 degree arc from its right front to left quarter. See post #13 for why screening either of these positions was beyond the logistic capabilities of an armoured Regiment.

The best example of a tank generated smoke screen in NW Europe was the smoke screen fired by the Sherman tanks of JOE Vandeleur's Irish Guards to support the assault river crossing by the US Paratroops over the river Waal in September 1944. The assault crossing took longer to launch than expected and the tanks expended their smoke ammunition long before the paratroops started crossing the river (The Hail Mary mother of God sequence in a bridge to far). As a result not only was the smoke screne ineffective but the Irish Guards had no ammunition and were not available to exploit the successful river crossings at Nijmegan.

Its a matter of scale, and logitiscs. If you want a smoke screen of any significance to a Corps battle the key technology is the RASC 3 tonner and not the 3.7" howitzer!


Note 1 - this battle was heavily studied in the 1980s as the template for halting an amour heavy force on the North German plain. .

 

Mapshooter,

by 1944 a commander of a 75mm tank had a better response - load their own smoke.rounds or plaster the suspected target with HE - but locating the enemy was easier in theory than practice. E.g it took 30 years for von Rosen who commanded a platoon of Tigers in 503 hytk bn hit by AP shot to realise that the fire was from (friendly) 88mm guns firing from Cagny, and only then after walking the battlefield with the British Army Staff College in company with von Luck who had sited the AA guns. .

Going back to the point Phylo made, Hobart's remarks do provide a clue about the thinking behind the CS Howitzers. If he genuinely thought that all it might have taken for Goodwood to succeed was for tanks to make better use of smoke then it calls into question his tactical judgement and his attitude to all arms co-operation. .

Currently, Percy Hobart was one of the great British Armour pioneers, a pre war expert on mechanization, and the charismatic trainer who formed three of the British armoured divisions 7th, 11th and 79th. He was also seen as abrasive, intolerant of other peoples views and opinions - and denied an opportunity to command any forces in battle. If the leading expert in mechanization was described in his confidential report as "quick tempered, hot headed, intolerant and inclined to see things as he wished them to be rather than as they were." then this does not bode well for developing an all arms doctrine drawing on the best thinking in each arm. it might well explain how the British armour went to war with an exaggerated view of what could be done by tanks alone. The 3" and 3.7" CS howitzers are some byproducts from this episode of dysfunctional thinking.

Perhaps it is time to re appraise Hobart's reputation; as a menace and part of the problem rather than a misunderstood prophet..

 

An aside but it might be better to say 'it took Rosen 30 years to find an excuse to explain his retreat after 2 of his Tigers were knocked out'.
The Tigers of 503 were rendered inneffective by the bombing and they took very little(if any) part in the subsequent actions. They did not seem to have had any impact at all.
That leaves aside the complete lack of any evidence for the claimed flak guns in Cagny.
Lets give credit where it is due-Becker!


A CS Cromwell captured by the Germans and used by 12th SS had German ammunition when it was knocked out in late July.

All Cromwell's could make their own smoke...........

 

Idler...Or not entirely sure you can SEE the target - such as dug-in and camoflaged a/t guns. The CS tanks provide a rapid ability to screen potential positions on the battlefield.

No, they seem to have gone straight to smoke during the late 1920s exercises - then changed to more and more H.E. in the loadouts through the war years. But very slowly, and Gerry Chester's accounts show that they could and would switch back to 100% smoke when necessary.

Then again - compare that opinion of Hobart with TIm Harrison Place's opinions on Monty in his "Military Training in the British Army, 1940-1944: From Dunkirk to D-Day"....the similarity is suprising!

Of course it was dysfunctional - the British thought they were "setting the rules" in that period - developing the best doctrines. Experience proved that not to be the case.

Mapshooter - it also requires you to get a lot closer with H.E. to be guaranteed effective with short-range, low velocity weapons like the 3/3.7in tank howitzer than with smoke Smoke can do the job of blinding a position anywhere in front of said position allowing for drift etc...but H.E. has to either hit or drop within fragmentation range.

...which is a problem in North Africa - where it doesn't matter what the British tank was firing, a gun tank firing 2pdr shot or a CS tank firing H.E....if it's facing a tank or antitank gun that can reach out further than the British tank's own maximum range.

 

Of course it was dysfunctional - the British thought they were "setting the rules" in that period - developing the best doctrines. Experience proved that not to be the case.


Whatever the similarities others have drawn between the brothers in law Hobart and Montgomery, the phrase "horses for courses" comes to mind . Montgomery was a commander whose judgement was vindicated by results. Hobart was the head of a corps and needed to co-operate with his peers in other arms. Hobart's confidential report is a primary source of his failure in his role. Tim Harrison Place's opinions about Montgomery are just a historians comment.

You are mistaken. The dysfunctional element of British pre war thinking about armour was that it focused on the tanks at the exclusion of other arms - an approach which has a certain parallel in this thread

 

Actually - no; what was dysfunctional about it was that it was the product of extensive testing and exercising to prove the superiority of the tank and associated mechanized forces - the traditional error of deciding what results you want to achieve/show, and measuring all tests, intelligence etc. for proof of that result.

The whole idea of the Experimental Mechanized Force was flawed as an experiment; it was established and exercised by proponents of mechanized warfare, and they learned their own lessons out of it I.E.the scope/shape of the exercises, the favourable umpiring etc. told them they were right because they were always going to show them they were right. That's how the experiment was conducted.

As with any learning exercise - the proponents of mechanized/armoured warfare should have tested BOTH sides of the equation, and tested their ideas for failure....not just how right they could be

It's an amazingly common failure. FORTITUDE depended on it, Hitler did it to himself in the six weeks after Dunkirk, "Beppo" Schmidt screwed the Luftwaffe in the Battle of Britain doing it....and we did it to ourselves during the Englandspiel.

And we've been debating how he achieved those results for nearly 70 years. That's not exactly "vindicated"...

 

Unless the target to be blinded is very small smoke still has to be placed in the right place, taking account of the wind speed and direction. Even when it is small you may well drop the smoke fairly close but it still needs to be in the right place. Sudden wind changes are the enemy of effective smoke. Furthermore you can never be sure of what the wind is doing until you've dropped some smoke there.

The problem is not dramatically different with HE neutralisation (ie suppression), you are not trying to hit a target element you are trying to put rounds in the area to keep the enemy's heads down. Dispersion is actually a good thing, it adds to the target's uncertainty (knowing that the enemy is shooting at the wrong place is good for morale) and ensures you cover a reasonable area and neutralise it effectively, identifying the extent of enemy position is too often easier said than done.

There's an added point that nobody has spotted, was the smoke BE (ie ejecting cannisters) or WP (ie bursting). In WW2 UK arty used BE, with two exceptions - 3.7-in How (being designed for mountains, BE wasn't a great idea because the cannisters tended to bounce down hill) and 105mm M7. The problem with WP is that it blinds a smaller area so more rounds are needed, and its hot smoke tends to go upwards in hot dry weather.

The word 'accuracy' keeps popping up and its clear that one or two posters aren't entirely up to speed on its meaning (the notion of an inherently inaccurate gun is utter tosh, I do wonder which under-informed twat originates this sort of nonsense). Accuracy is the measure of the mpi from the aimpoint, direct fire guns, being short range, are accurate providing they undertake regular sight tests and their MVs are close to the MV that the sights are designed for; artillery is a bit more complicated due to the effects of non-standard conditions at longer ranges and the need for accurate data about these conditions and the way the data is used. Consistency is the dispersion of the fall of shot around the mpi, with direct fire it's generally small because ranges are small (and times of flight are short). Dispersion increases as range & time of flight increases (for a given range the longer ToF, ie lower velocity, will give greater dispersion).

 

Mapshooter, the nature of the round(s) for the 3.7in tank howitzer isn't clear...NOR for the 3in howitzer! There's very little information available on either. That's one of theings I;m trying to find out.

There WERE two different TWO-inch rounds for the tank "bomb thrower", HCE and WP....but that is better recorded because they're the same rounds as the ML 2in infantry mortar.

And that's the rub. In the Churchill MkI hull-mounted howitzer the same type of telescope was used for the low muzzle velocity howitzer as the high muzzle velocity 2-pdr in the turret.

 

mapshooter,

I suspect non gunners confuse "accuracy" with Probable Error of Range (or Azimuth ) - the zone.

it is not true to state that direct weapons are inherently accurate, because the Probable Errror of Range varies between types of ordnance and with the charge. The same gun layer with well calibrated sights correctly layed on the target will hit it more often using a charge whcih minimises the PE R . Look at the FH 70 range table extract uploaded in post #11 The deviation in trajectory using charge 1 might not matter at 100m range but will at 1000m. Using charge 8 the FH70 is a useful anti tank gun, with a good chance of a hit: using charge 1 a gunner would have to be lucky to achieve a direct hit on a tank sized target.

Any more like this and you can walk back to the gun posiiton. ...

 

Not forgetting the obvious: some TNA hits for "tank howitzer", the least unreliable search term.

 

Straight away the most interesting thing that leaps to the eye is that ordnance for the 3in howitzer was being tested in 1937. Which at least gives a starting date of "on or before" April 1937 for the project.

I know that doesn't sound much - but beyond the entry on Wiki and in Chamberlain&Ellis, this weapon is remarkably transparent in paper terms!

 

And I wonder if the 'Gun Design Committee' report has any historical information? 1945 seems a bit late to be testing it.

 

Yeah, I wondered about that too. Were the Australians still using their 3in howitzer-armed Matildas in the South Pacific that late?

 

Phylo:

As far as I know from working on the 9th Australian Div, the Australians were still using the 3" how on the Matilda in '45. I believe the usual practice was to have one tank per troop with the 3", while the others had 2 pounders. The drill was for the 3" tank to strip cover away from Jap bunkers with HE, after which the 2-pounder tanks would snipe the embrasures.