Wednesday, October 26, 2016
The M32 tank recovery vehicle was the only Sherman engineer tank variant to be produced in volume. Changes from the standard gun tank specification included the addition of a large, fixed superstructure in place of the turret, and an 81mm smoke-laying mortar fitted to the top of the hull. There was a 60,000lb winch in the fighting compartment, and a pivoting A-frame jib on the hull. The photograph shows the M32B1 variant using the cast M4A1 chassis.
The British-designed Sherman ARV Mk II incorporated a Croft 60-ton winch in the fighting compartment, a detachable 3.5-ton winch at the front and a fixed 9.5-ton winch at the rear. There was also a substantial earth anchor and a fixed ‘turret’ in which was installed a dummy gun.
The most effective Sherman-based anti-mine device was the chain flail, consisting of a large cylinder carried ahead of the tank to which were attached a series of chains. In this photograph the side covers of the flail have been removed to show the chain drive.
The flame-thrower is a very effective weapon against entrenched infantry. This Sherman M4A3E8, photographed in Korea, has been equipped with a flame projector – possibly the US Marine Corps POA-CWS 75 H1 device – operating through the barrel of the main gun.
The origins of what are generally called ‘engineers’ tanks’ date back to the earliest days of tank warfare, when in 1917 the British Army modified a number of their Mk IV heavy tanks to facilitate the crossing of deep ditches or trenches. The tanks were adapted to carry fascine bundles or hollow timber cylinders that could be dropped into the ditch in such a way that the tank could drive across it. Mk IV and Mk V tanks were also equipped as bridging tanks by being fitted with hinged ramps to provide a means of crossing other obstacles. Others had their armaments removed and were adapted for use as supply vehicles or gun carriers, while the armoured recovery vehicle was developed by the simple expedient of attaching a jib and pulley block, or a powered crane, to the front of an older or obsolete tank. After the Armistice was signed in 1918 development of the machines generally came to a halt, with few special tanks produced during the interwar years. The outbreak of the Second World War brought a resurgence of interest in using what were essentially modified tanks for specialised roles, particularly for recovering disabled armoured vehicles, a task that was often beyond the capabilities of existing wheeled heavy tractors.
Engineers’ tanks really came into their own during the D-Day landings. In the months preceding the invasion a range of so-called ‘funnies’ was developed, each tasked with overcoming a particular problem, and these vehicles made an enormous contribution to the success of the landings. The fact that the Sherman was plentiful, simple in construction and above all reliable made it the ideal choice for producing a whole range of these specialised vehicles, for example flail tanks, mine-clearing devices, rocket-launchers and flame-throwers. Most of the conversions were ‘official’, but others, including the mounting of a double-track assault bridge on the Sherman nose, were field modifications made in response to the changing situation on the ground … and the US authorities did not necessarily always agree with what the British were doing to ‘their’ tanks.
The US Army’s M32 tank recovery vehicle was the only Sherman engineer tank variant to be produced in significant volume, and the pilot model, built by Lima Locomotive in 1943, was constructed on the hull of a standard M4 from which the gun and turret had been removed. It was originally designated TRV (tank recovery vehicle) T5, and changes from the standard gun tank specification included the addition of a large, fixed superstructure mounted in place of the turret, and an 81mm smoke-laying mortar fitted to the top of the hull. A 60,000lb winch was installed in the fighting compartment, and there was a pivoting A-frame jib on the hull, mounted in such a way that it could be used in conjunction with the winch. Additional tow points and equipment stowage facilities were also provided. The design was standardised as the M32 in September 1943. Later variants included the M32B1, based on the hull of the M4A1; the M32B2, which used the M4A2 hull; the M32B3, using the hull of the M4A3, including some examples with HVSS suspension; and the M32B4, which used the M4A4 hull, but never made it into production. As well as Lima Locomotive, M32 recovery vehicles were constructed by the Baldwin Locomotive Works, Federal Machine & Welder, International Harvester and Pressed Steel Car.
Entering service in 1944, the M32B1 was also converted into a prime mover for heavy artillery by the removal of the A-frame; in this form it was designated ‘full track prime mover M34’.
The British Army also used the M32 recovery vehicle, describing it as the ‘armoured recovery vehicle (ARV) Mk III’, but the workshops of the Royal Electrical and Mechanical Engineers (REME) also constructed a ‘British’ Sherman-based recovery vehicle that they designated ‘ARV Mk II’. The vehicle incorporated three winches – a Croft 60-ton winch installed in the fighting compartment, a detachable 3.5-ton winch at the front, and a fixed 9.5-ton winch at the rear; there was also a substantial earth anchor designed to hold the vehicle in place during heavy ‘pulls’. In order to camouflage the significance of the vehicle, there was also a fixed ‘turret’ in which was installed a dummy gun.
REME also developed a more specialised vehicle for recovering drowned or disabled tanks, or other vehicles, from the D-Day landing beaches. Based on the hull of a Sherman from which the turret and gun had been removed, the so-called beach armoured recovery vehicle (BARV) had the hull sides extended in height by the addition of face-hardened armoured plate. Although the driver was reliant on instructions from the commander, the vehicle was able to wade in up to 8ft of water without being swamped. A wooden pusher pad on the nose minimised the possibility of damage when soft-skinned vehicles were being recovered.
Equally well known for their role on the D-Day beaches are the so-called ‘duplex-drive’ (DD) amphibious tanks. Surprisingly, the British Army had actually started to test amphibious tanks during the First World War, but development did not reach a stage where the vehicles were considered to be reliable. It wasn’t until June 1941 that the Hungarian inventor Nicholas Straussler finally solved the problem of making tanks float by the simple expedient of fitting a folding heavy canvas screen to a frame welded around the top of the hull. With the tank in the water, this increased the displacement of the hull to the point where the tank was able to float with the hull below the waterline. Compressed air was used to raise the screen, and it was held in place by mechanical stays. A second drive system transferred power from the track drive sprockets to rear-mounted propellers, and steering was achieved by means of a rudder, and by rotating the propeller mountings in a horizontal plane.
Much impressed by Straussler’s folding screen, Major General Percy Hobart of the British 79th Armoured Division carried out swimming trials in Portsmouth harbour, and the success of these trials led to the selection of the British Valentine for the development of the duplex-drive tank. At the same time plans were also put in hand to convert Shermans for the role. Although most of the American, British and Canadian DD tank crews did their preliminary training using Valentines, it quickly became apparent that the Sherman was more suitable for amphibious use and both M4A2 and M4A4 variants were modified. The drive to the propellers was taken from the rear sprockets using bevel gears, which meant that the tracks were running as soon as the tank touched the beach, and the propellers were designed to hinge upwards when not in use. The height of the canvas screen was also increased when compared to the Valentine. DD Shermans were used, with some patchy success, on D-Day, as well as during the Rhine crossing in 1945.
Shermans were also successfully adapted to carry the much-feared flamethrower weapon.
Back in 1940 the British company Lagonda Motors had constructed and demonstrated a portable flame-thrower device that could project burning petroleum-based fuel a distance of 100ft, and eventually managed to extend this range to around 350ft. It was initially imagined that the weapon could be used for the protection of shipping and airfields against low-level attack by aircraft, but neither the Royal Navy nor the Royal Air Force showed much interest and further development concentrated on mounting the flame-thrower on either a truck or a tracked vehicle. In this form the British Petroleum Warfare Department (PWD) hoped that the weapon would prove to be effective against pillboxes and strong points. By the end of July 1942 the flame-thrower had been successfully adapted to allow it to be fitted to a tank, and versions were produced using both the Valentine and the Churchill, the latter carrying the flame-thrower fuel in a trailer. Known as the Churchill Crocodile, this version was selected for production, but the British and Canadian Armies also produced experimental Sherman flame-throwers under the names Ronson, Salamander and Adder.
The US Army similarly produced flame-thrower devices that could be mounted on the Sherman. In some cases the flame projector was fitted into the co-driver’s periscope aperture or the hull machine-gun position, while in other cases it replaced the main gun. In late 1944 the US 2nd Armored Division also adapted four Shermans to mount the Churchill Crocodile flame-thrower.
Another role in which the Sherman was hugely successful was that of mine clearance. Large numbers of anti-tank mines were laid by the opposing armies, and in addition thousands of anti-personnel or land mines also presented considerable danger to the advancing armies. Various solutions to the problem of dealing with these mines were proposed, including explosive devices, flails, rollers and ploughs, all of them designed to be attached to modified tank hulls. Many were immediately dismissed as being impractical, but others were developed to the point where they were quite successful. Of these, the flail proved to be the most effective.
Work on a mine flail had started in 1939 when the British Mechanization Board had proposed that anti-tank mines could be exploded in situ by means of weights attached to the ends of spring-steel strips; the strips were attached to a revolving drum carried ahead of a tank. It was quickly found that the device was more effective if the spring-steel strips and weights were replaced by revolving chains, and initial trials of what was described as the Baron Mk I were carried out with a Matilda II tank. This was followed by the Baron Mk II, which was equipped with a hydraulic raising and lowering system for the rotor. During 1942 a simpler flail device, dubbed Scorpion, was developed in the Middle East, and by the end of July 1943 Scorpion had been issued for user trials, before being abandoned. However, during the previous month there had been considerable progress with mounting a modified version of the Scorpion on a Sherman tank, and this became the most successful of the flails. Designated Crab, the first prototype was ready for trials in September 1943 and the system proved to be very effective at destroying mines and cutting barbed wire.
Other approaches to the problem of mine clearance included explosive devices, ploughs and rollers. The Sherman Snake and Conger were both explosive devices and consisted of a long hosepipe or cylinder of explosive material that was intended to be pushed across a minefield and detonated remotely, thus exploding the mines ahead of the advancing tank. A similar device, dubbed Tapeworm, consisted of a flexible hosepipe that was designed to be towed across the minefield by a flail tank; once in position, it was filled with liquid explosive and detonated.
Tank-mounted ploughs designed to expose anti-tank mines were developed before the Second World War by agricultural engineers John Fowler & Company, but despite considerable work the device never lived up to its original promise. The British 79th Armoured Division developed a version of the plough, dubbed Bullshorn, testing it in conjunction with a Sherman. It was eventually abandoned in favour of the flail, but a few Bullshorns were useful on D-Day for filling in craters caused by exploding mines.
Anti-mine rollers had been developed in the years immediately following the end of the First World War, and were designed to detonate mines by simulating the weight of a tank rolling over the fuze. By 1937 John Fowler & Company had successfully trialled an anti-mine roller attachment (AMRA) consisting of a girder frame that was effectively pushed ahead of a tank, and which carried four heavy rollers. This idea was adapted to produce the Sherman-mounted anti-mine reconnaissance castor roller (AMRCR), which proved useful against anti-personnel mines. Spiked rollers were also tested experimentally in the Middle East, and one such device, dubbed Porcupine, was trialled in Britain in conjunction with a Sherman.
The most successful anti-mine roller was the Canadian indestructible roller device (CIRD). Constructed at the Canadian Army Workshops at Borden during 1943, the CIRD consisted of two rollers of solid forged armour-quality steel, 16in wide and with a diameter of 26in, each weighing around a ton. The rollers were carried on trailing arms suspended on a substantial cross-shaft, arranged to pivot some distance ahead of the tank in front of each track. Helical springs were provided to hold the trailing arms in the operating position. The CIRD was standardised for use with both the Sherman and the Churchill in May 1945, although further development of roller devices was eventually abandoned in favour of the more successful flail. Nevertheless, other roller devices such as Rodent, Aunt Jemima, Earthworm, Centipede and Lulu all achieved some degree of success. The last named brought a little more technology to the problem by adapting the successful Polish electro-magnetic mine-detection system for use with a tank. Finally the remote ‘mine roller T10’ replaced the track system of the Sherman with three huge rollers mounted tricycle fashion on swing arms.
The Sherman was also used, at least by the US Army, as a rocket-launcher mount. Various systems were developed, but only two – the ‘T34 Calliope’ and ‘T40 Whizbang’ – saw combat use. Dating from 1943 and used by the US 2nd Armored Division in France in 1944, Calliope consisted of sixty 4.6in rocket tubes mounted in a frame above the turret; the mount could rotate with the turret and the tubes were elevated by a mechanical link to the gun barrel. Whizbang was also used in combat in 1944/45, and consisted of twenty 7.2in rockets in a hydraulically elevated box mount.
Consideration was also given to adapting the Sherman to provide what the British would have described as an assault vehicle or ‘armoured engineers’ vehicle’, and in April of 1945 a prototype was produced for the ‘demolition tank T31’. The vehicle was constructed on an M4A3 chassis with the horizontal volute spring suspension (HVSS) system; the thickness of the floor was increased to 1.5in and both a flame projector and a ’dozer blade were fitted. The massive turret mounted a 105mm howitzer, with a 7.2in T94 rocket-launcher to either side; the rocket launcher incorporated a revolving feed mechanism that held five rounds, and reloading could be carried out from inside the hull. A single prototype, with a dummy 105mm gun, was delivered to Aberdeen Proving Ground in August 1945, but the project did not extend beyond the prototype stage and was subsequently cancelled.
Lastly, mention must be made of the inflatable canvas and rubber ‘Shermans’ that were deployed in 1943/44 as part of ‘Operation Fortitude’ – the deception plan that fooled the Germans into thinking that the invasion would come from Kent into the Pas de Calais region of France. All kinds of tactics were used, including dummy tanks and aircraft, fake radio traffic, and even the recorded sound of heavy trucks apparently moving around dummy marshalling areas. Comprising four separately inflated chambers, the dummy ‘Shermans’ were given realistic markings, as well as having nuts and bolts and other detail painted onto the canvas. Once inflated, the dummy ‘tanks’ were lined up in rows and covered with camouflage netting. Inflatable ‘Shermans’ were also used during ‘Operation Shingle’ at Anzio, in an attempt to confuse the enemy regarding the real location of Allied tanks.
Thursday, August 25, 2016
Friday, August 5, 2016
Monday, March 14, 2016
For a variety of reasons tank design in the UK and, to a lesser extent in the USA, had one distinguishing feature. The tanks were always two years out of date. When the German armour had the equivalent of 4- or 6-pounder guns, the British tanks had 2-pounders. When the British upgraded to 6-pounders, the German tanks had the incredible 88 mm. When the three British armoured divisions and eight armoured brigades landed in Normandy their Churchills, Cromwells and Shermans were hopelessly outgunned.
Half the German tanks in Normandy were the Panzer Mark IV ‘special’. It weighed 25 tons, moved at up to 25 mph, and its 75-mm Kwk 40 gun could penetrate 84 mm of armour at 1,000 yards. Its own front armour was 80 mm. The Panzer Mark V or Panther accounted for nearly 40 per cent of German tanks in Normandy; that is, one of every two tank regiments in most German armoured divisions was equipped with Panthers. It weighed 45 tons, could move at 35 mph, and its 75-mm Kwk 42 guns with a 14-pound shell could penetrate 118 mm of armour at 1,000 yards. Its own front armour was 100 mm. The Panzer Mark VI, or Tiger, was very nearly impossible to knock out. It weighed 54 tons with a maximum speed of 23 mph and carried 100 mm of frontal armour. Its 20-pounder shell from a 88-mm Kwk 36 gun could penetrate 102 mm at 1,000 yards.
Many German tank units had one Panther per troop of Mark IVs, a situation similar to the British units, which had one Sherman Firefly per troop. The Allied Sherman tank weighed 32 tons and could travel at 25 mph, but its front armour was only 76 mm thick. It could be knocked out by any German tank at 1,000 yards, even at 2,000 yards, and so was known as the ‘Tommy-cooker’. Its 75-mm gun could at best penetrate 74 mm at 100 yards, 68 mm at 500 yards, and 60 mm at 1,000 yards. However, its Ford engine was reliable and easy to maintain.
Trooper John Thorpe was the ‘Jack of all trades’ in 4 Troop C Squadron, 2nd Fife and Forfarshire Yeomanry, equipped with Shermans:
I could be called upon to take any other crew member’s place and I was the disposable member of the crew. I was sent on foot reconnaissance to find the safest place to locate the tank without placing it in jeopardy when advancing slowly towards a vantage point in a hedge or out of a wood, or at a crossroads in a village, or to attach a tow rope to help extract a disabled tank in the thick of battle. I developed not only a sixth sense but a super sense, a soldier’s deepest sense, the sense to survive.
The reality of this equation was very disturbing. Unless a 76-mm Sherman could get very close to the opposition or by chance catch it sideways on (Tiger had 80 mm of side armour, Panther 45 mm and Mark IV 30 mm) the contest was inevitably one-sided. Only the 17-pounder Sherman Fireflies were capable of a level fight. A limited number of Challengers – 200 in all – were allocated to Guards Armoured Division and 15/19th Hussars in 11th Armoured. A 17-pounder anti-tank gun was mounted on a Cromwell chassis and allocated on the basis of one per troop, with a crew of five. However, the German dual-purpose 88-mm gun (ground and AA) was reckoned to be the best available during the Second World War. Its muzzle power could destroy any Allied tank at 2,000 m and its airburst fuse could put a shell on top of a crossroads eight times out of ten. Bill Close, squadron commander with 3 RTR throughout the campaign, was wounded three times and awarded two MCs. As author of Panzer Bait, and having had no fewer than eleven tanks knocked out from under him, his views on tanks have much authority!
Our ordinary 75-mm gun could not knock out either a Tiger or a Panther except at about 500 yards range, and in the rear, and with a bit of luck in the flank! The 17-pounder Firefly was our best tank but even it could not penetrate the Tiger head-on at over 1,000 yards. Whereas all our tanks would be knocked out at 2,500 yards by the German 88-mm gun.
Steel Brownlie, troop leader with 2nd Fife and Forfarshire Yeomanry, also fought throughout the campaign, was wounded and awarded the MC. He wrote The Proud Trooper, a story of the Ayrshire Yeomanry. His comments are:
The great snag was that the Sherman, mechanically reliable and available in great numbers, was inferior in many ways to the German tanks. The armour was thin, the ammunition was stowed in open bins so that it exploded if there was any penetration. A hit almost inevitably meant a brew-up. Some boffin hit on the idea of welding bits of extra armour to protect the bins but their effect was to provide an aiming mark. I certainly saw many brewed-up Shermans with a neat hole in the ‘extra armour’. Even if you fixed spare track plates to the front of the Shermans, the basic weakness remained. You were in a ‘Ronson’ and if you were hit it was best to bale out p.d.q.
He also stressed the fear generated by the awareness of inferior armour: ‘My crews got almost obsessive about NOT having a thick, sloping glacis plate in front like the Panther. I recall deliberately backing into a firing position so as to have the protection of the engine. There was the added advantage that if you had to get out in a hurry you had all the forward gears.’
‘Sandy’ Saunders, troop commander with 2nd Northants Yeomanry, wrote:
The regiment had been training since 1939 as an armoured regiment in both an anti-tank and reconnaissance role. It was a pity that their equipment was inadequate. The Cromwell was designated a cruiser tank, fast across country but under-armoured and under-armed. The 75-mm gun was only capable of knocking out German Mark IV and Panther tanks at point blank range while their 75 mm and 88 mm (converted AA guns) could knock out a Cromwell at extreme range. We only started to get 17-pounder guns in the Challenger version of Cromwells in August – too late for 2nd Northants Yeomanry to try out in action.
Simon Frazer, 15/19th Hussars, commented:
My appreciation of tank v. tank situations was coloured by three oversized factors favouring the enemy, viz silence, muzzle velocity and thick sloped armour. We had to match this with the speed, manoeuvrability and camouflaged outline of our Cromwells. ‘David and Goliath’ I told my dispirited crew to cheer them up. Our 75 mm became known as ‘the sling’ thereafter.
Reg Spittles, 2 Troop Corporal A Squadron, 2nd Northants Yeomanry, described some of his tactics:
I found that if in doubt to stand back and put a couple of ‘smoke’ shells into the area. If it was a possible anti-tank gun or infantry ambush that would often resolve the situation and cause an enemy withdrawal.
Tank maintenance itself gave few headaches because the Cromwell – Rolls Royce engine, transmission, tracks and traverse – was such a reliable vehicle. The 28-ton tank was reliable on the road, but its 75-mm gun shots bounced off Tiger full frontals. On dry hard fields Cromwell IVs and VIIs would do over 30 mph in fifth gear. But the story gets worse.
Every infantry battalion feared the noisy Nebelwerfer mortar, an ugly multi-barrelled brute on wheels, and easily towed. Its ‘moaning minnie’ stonks are said to have accounted for 75 per cent of infantry casualties in Normandy. They came in three sizes with a maximum range of 8,600 yards, and most of the five Nebelwerfer regiments (each of sixty projector-mortars) were concentrated on the British/Canadian front.
Only the British 25-pounder field guns with a range of up to 13,400 yards, and 4.5-in./5.5-in. medium guns meshed together in troop, battery and regimental and the larger ‘Uncle’ and ‘Victor’ targets were capable of inflicting dramatic large-scale protective barrages or defensive fire plans. Their pinpoint DF and DFSOS targets were praised by the infantry.
The Spandau was a faster firing weapon than the Bren, the Schmeisser better than the cheap little Sten gun. The Panzerfaust one-shot anti-tank missile was more effective than the British Piat. Major Ned Thornburn, Company Commander 4 KSLI, had these views: ‘The Bren was adequate, the Sten did nothing to heighten our chaps’ morale, the Piat was not reliable, often ineffectual – the Panzerfaust was better. Our 3-in. mortars were, however, as effective as their Nebelwerfers.’
The Germans laid hundreds of thousands of mines, mainly Teller mines, in roads or on verges. These could be gingerly excavated after location or lassooed with a long rope and towed away. Booby traps in houses were rarely defused by the REs, but simply blown up on the spot. But one of the greatest perils to infantrymen was schu-mines or S–mines planted randomly in fields and verges. The former were explosives contained in a wooden box more or less undetectable by the usual mine detectors. They exploded with the pressure of a foot on the buried lid. The latter were just as lethal – small anti-personnel mines activated by a trip wire, which exploded at waist height. The schu-mines would take your legs off and the S–mines would tear your whole body apart.
Field Marshal Montgomery, who had some capacity for deluding himself, wrote to Alan Brooke:
I have had to stamp very heavily on reports that began to be circulated about the inadequate quality of our tanks, equipment, etc. as compared with the Germans…. In cases where adverse comment is made on British equipment such reports are likely to cause a lowering of morale and a lack of confidence among the troops. It will generally be found that when the equipment at our disposal is used properly and the tactics are good, we have no difficulty in defeating the Germans.
Absolute rubbish of course, unless a ratio of five to one in tank losses was considered acceptable. Simon Frazer’s 15/19th Hussar troop peppered a Mark V tank west of Argentan and hit it twenty-two times. They found the Mark V the next morning. It had been abandoned by its very gallant crew because it had run out of petrol. Admittedly its turret superficially resembled a cheese grater, but not one hit had penetrated.
Lieutenent-General Horrocks, XXX Corps Commander, knew the score. He wrote: ‘Our Shermans and Cromwells had to approach within 500 m of the heavier Panther or Tiger tanks to knock them out, whereas the 88 mm or the Tiger could dispose of Allied tanks at 2 km. The Panther’s gun was superior to Cromwell or Sherman, and Mark IV was certainly their equal.’
With the benefit of hindsight, there should have been many more 17-pounder Sherman Fireflies available before D-Day. The meagre supplies were ‘reserved’ for British armour despite belated American recognition of their superiority in the field. Bill Close, 3 RTR, commented: ‘The Comet tank (finally issued early in 1945) was the last contributed by Britain’s tank manufacture during the war. With a maximum 100 mm of armour, 77-mm gun and speed of 30 mph, it could tackle all but the King Tiger.’
But at least the Allies had almost total superiority in the air. Although at one time or another most units were bombed by the Luftwaffe and the RAF, and almost inevitably were shot up by USAAF prowling Thunderbolts, the universal view was ‘Thank God for the Tiffies.’ 155 Typhoon pilots were lost over the Normandy battlefields engaging in a very close support against Boche strongpoints, tanks, or dug-in 88-mm anti-tank guns, but many individual ‘little’ battles were won and precious lives saved by the RAF intervention. LIMEJUICE was the magic radio call that produced – often from a cab-rank of circling predatory Typhoons – almost miraculous support. The FOOs who were given the opportunity of calling for LIMEJUICE via the regimental radio network, had a feeling of power, of waving a magic wand. There is no doubt that the RAF was very highly regarded by the front line troops despite the occasional ‘incidents’.