Sticky bomb

Last updated

Sticky bomb
Production of Sticky Bombs.jpg
Sticky bombs being manufactured
Type Anti-tank hand grenade
Place of originUnited Kingdom
Service history
Used byUnited Kingdom
Canada
Australia
France
Wars Second World War
Production history
Designer Stuart Macrae
Designed1940
ManufacturerKay Brothers Company
Produced1940-1943
No. built2.5 million
Specifications
Mass2.25 lb (1.02 kg) [1]
Length9 in (230 mm)
Diameter4 in (100 mm)

Filling Nitroglycerine (Nobel's No. 823 explosive) [1]
Filling weight1.25 lb (0.57 kg)
Detonation
mechanism
Timed, 5 seconds

The "Grenade, Hand, Anti-Tank No. 74", commonly known as the S.T. grenade [lower-alpha 1] or simply sticky bomb, was a British hand grenade designed and produced during the Second World War. The grenade was one of a number of ad hoc anti-tank weapons developed for use by the British Army and Home Guard after the loss of many anti-tank guns in France after the Dunkirk evacuation.

Contents

The grenade was designed by a team from MIR(c) including Major Millis Jefferis and Stuart Macrae. It consisted of a glass sphere containing an explosive made of nitroglycerin and additives which added stability. When the user pulled a pin on the handle, the casing would fall away and expose the sticky sphere. Pulling another pin would arm the firing mechanism and the user would attempt to attach the grenade to an enemy vehicle. Letting go of the handle would release a lever that would activate a five-second fuse, which would then detonate the nitroglycerin compound.

The grenade had several faults in its design. The Ordnance Board of the War Department did not approve the grenade for use by the British Army, but intervention by the prime minister, Winston Churchill, led to production of the grenade. [3] Between 1940 and 1943, approximately 2.5 million were produced. It was primarily issued to the Home Guard but was also used by British and Commonwealth forces in North Africa. It was used by Allied Forces on the Anzio Beachhead, including the First Special Service Force; as well as by Australian Army units during the New Guinea campaign. The French Resistance were also issued a quantity of the grenades.

Development

In 1938, Maj. Millis Jefferis developed an anti-tank weapon that would be ideal for irregular warfare. It would have an explosive charge deform so that it had a substantial area of intimate contact with the surface of the target. [4] Upon detonation, the explosion would be focused on a small area capable of rupturing an armoured plate. [4]

Sappers call such a device a "poultice" or "squash head" charge. [4] Jefferis enlisted Bauer and Schulman of the Colloid Science Department of Cambridge University. They experimented with different lengths of bicycle inner tubes filled with plasticine to represent explosives, fit them with wooden handles, and dipped them in rubber solutions to make them sticky. In experiments, the prototypes proved difficult to aim and only stuck to the metal bins, representing tanks. [5]

With the end of the Battle of France and the evacuation of the British Expeditionary Force from the port of Dunkirk between 26 May and 4 June, 1940, a German invasion of Great Britain seemed likely. [6] However, the British Army was not prepared for a German invasion; in the weeks after the Dunkirk evacuation, it could only field 27 divisions. [7] The army had a shortage of anti-tank guns, 840 of which had been left behind in France and only 167 were available in Britain; ammunition was so scarce for remaining guns that regulations forbade even single rounds being used for training purposes. [7]

Under the circumstances, Jefferis considered that his idea might be more useful for the British Army and Home Guard. Jefferis was in charge of the MIR(c) department, tasked with developing and delivering weapons for use by guerrilla and resistance groups in occupied Europe. [8] MIR(c) was now charged with development of the sticky bomb, with Robert Stuart Macrae being assigned to design the sticky bomb. [5]

Gordon Norwood, a master printer who recruited Macrae from his former magazine publishing employer, suggested a frangible container was needed to contain an explosive gel. He obtained a 150-Watt light bulb to demonstrate that a spherical glass flask inside a sock of woven wool would be rigid when thrown. Upon contact, the glass would break and the bomb would deform to the required shape. [9] Experiments with glass flasks filled with cold porridge confirmed this was a viable solution. [10]

The grenade needed a delay for the thrower to get clear, so the woollen sock was covered in a sticky substance, ensuring the bomb stayed in place immediately prior to denotation. [10] Having covered the bomb in glue, a non-sticky handle was required. In the handle, a delay fuse was ignited by releasing a sprung lever so that a five-second time delay started as the grenade was thrown, similar to those on a conventional Mills bomb-type hand grenade. [11]

Macrae had a tin of birdlime labelled with a large letter K and an indication that tin came from Stockport but with no more clues as to the manufacturer. Macrae got on a train to Stockport and there found a taxi driver who took him to Kay Brothers Ltd. [11] The company's chief chemist was soon working on the problem of a suitable adhesive and within a matter of weeks the problem was solved to Macrae's satisfaction. [12]

The filling for the bomb was developed by ICI [11] and was nitroglycerin-based with additives to make it more stable and viscous. The glass flask containing the main charge held 1.25 lb (0.57 kg) of this explosive that was described as having the consistency of Vaseline. [13] The adhesive surface was protected by a light metal case which was released by pulling a safety pin. Early models also had a strip of adhesive tape round the neck of the casing. However, there were problems with service regulations that were not written with such an unconventional weapon in mind. [14] The prime minister, Winston Churchill, who was concerned with the state of the country's anti-tank defences, learnt about the grenade and urged its development. [15]

The Ordnance Board of the War Office did not approve the grenade to be used by the army. [16] Churchill still ordered further tests to be conducted in July and that it immediately be put into production. [17] His memo of October 1940 simply read "Sticky bomb. Make one million". [18] A couple of days later, Anthony Eden, then Secretary of State for War, added a scribbled note to a cabinet minute that recorded the order to go ahead with the bomb:

In spite of top-level pressure, the arguments rumbled on. Trials were disappointing, it was not possible to get the bomb to adhere to any surface that was wet or covered with even the thinnest film of dried mud "a customary condition of tanks" as Major-General Ismay, on 27 June, pointed out. [19]

Churchill was not amused:

General Ismay, I understand that the trials were not entirely successful and the bomb failed to stick on tanks which were covered in dust and mud. No doubt some more sticky mixture can be devised and Major Jefferis should persevere. Any chortling by officials who have been slothful in pushing this bomb, over the fact that at present it has not succeeded will be viewed with great disfavour by me. [20]

Macrae, Ismay and Churchill all saw fit to record these arguments over the technical issue of stickiness. [21] As Eden had pointed out, there was a lot at stake. The British infantry and Home Guard had little with which to put up a fight against tanks and to any who had witnessed trials of Molotov cocktails and SIP grenades it was evident that they could do little to a modern tank other than to provide a blinding pall of smoke. [22] What was needed was a hand weapon to deliver a coup de grâce by punching through the armoured plate. The sticky bomb could do the job and little else was available. [23]

In his memoirs, Ismay recalled that he never solved the puzzle of how to convey his very genuine concerns of the time to the right people. [24] A thrown sticky bomb simply would not reliably stick to a vertical surface; the bomb would stick if it was thrown onto the top of a tank, where the plates were more or less horizontal – and thinner – but this reduced the throwing range to 20 yd (18 m) at the most, getting that close would only be possible in an ambush or in street fighting. [25]

Churchill considered any obstruction, however well-meaning, as singularly lacking in imagination. In the event of invasion, he foresaw a desperate fight to the last and after the war, he wrote about how he envisaged the use of the sticky bomb, "We had the picture in mind that devoted soldiers or civilians would run close up to the tank and even thrust the bomb upon it, though its explosion cost them their lives. There were undoubtedly many who would have done it". He also later recorded how he intended to use the slogan "You can always take one with you". [26]

Arguments rumbled on and there were endless delays. Early versions of the sticky bomb were prone to leaks as well as breakage in transport. There were understandable concerns over the explosive charge, pure nitroglycerin is notoriously susceptible to the slightest knock, but the mixture developed by ICI proved to be very safe even if it should get into the hinges of the storage boxes. [27] By December 1940, fewer than 66,000 had been produced and the rate of production was disappointing at five to ten thousand per week. It was suggested that the original order of one million be reduced to 200,000. [23] Minor improvements were made, the most significant was to replace the glass flask with plastic. Finally, after passing all the required tests, the sticky bomb – now the No. 74 grenade Mk II – was accepted by the Ordnance Board; it was put into full-scale production, and it became a service issue. [28]

On 14 May 1941, Lieutenant-General Sir Ian Jacob reflected:

The most extraordinary feature of the whole business, however, was the fact that the Secretary of State for War, in a Minute addressed to the Prime Minister on 25 November 1940, said that the Director of Artillery and the Ordnance Board had only just been able to obtain from ICI the details of the explosive contained in the bomb. Seeing that the bomb was demonstrated in June 1940, this statement can hardly hold water. The War Office seems to be to blame in that, up to the end of April, 1941, no sticky bombs had been issued to any unit, nor had any dummies been provided for training. In view of our acute shortage of anti-tank weapons, the whole story is discreditable. [29]

Between 1940 and 1943 approximately 2.5 million were produced. [30]

Design

Sticky bomb diagram. British explosive ordnance Sticky Bomb-NAVORD OP1665.png
Sticky bomb diagram. British explosive ordnance

The grenade consisted of a glass sphere containing 1.25 lb (0.57 kg) of semi-liquid nitroglycerin, covered in stockinette (a kind of fabric) and coated with birdlime. A casing made out of thin sheet-metal and formed of two halves was placed around the sphere and held in place by a wooden handle, inside which was a five-second fuse. [32] The handle also contained two pins and a lever, which were pulled out to make the casing fall away and activate the firing mechanism. The user would run up to the tank and stick the grenade to its hull, using as much force as possible to break the sphere and spread the nitroglycerin onto the hull in a thick paste. [16] The lever would be released, and the fuse activated, and the grenade would then detonate. [33]

The grenade did possess several problems with its design. Users were urged to actually run up to the tank and place it by hand, rather than throw it, thus the adhesive could very easily stick to their uniform in the process; the user would then be placed in the unenviable situation of attempting to pry the grenade loose whilst still holding onto the lever. It was also discovered that as time passed the nitroglycerin began to deteriorate and become unstable, which made it even more difficult to use. [16] As the grenade was a short-range weapon, users were trained to hide in a trench or other place of concealment until the tank went past them, and then to stick the grenade to the rear of the tank, where its armour was thinnest. [34] Users were relatively safe from a few yards away, as long as they were not in line with the handle when it detonated. [35] The Mark II design used a plastic casing instead of glass, and a detonator instead of a cap. [36]

Operational use

Home Guard volunteers simulate an attack on a Valentine tank wielding Sticky bombs in 1943. The Home Guard 1939-45 H30178.jpg
Home Guard volunteers simulate an attack on a Valentine tank wielding Sticky bombs in 1943.

"It was while practising that a H[ome]G[uard] bomber got his stick [sic] bomb stuck to his trouser leg and couldn't shift it. A quick thinking mate whipped the trousers off and got rid of them and the bomb. After the following explosion the trousers were in a bit of a mess though I think they were a bit of a mess prior to the explosion."

Home Guard member Bill Miles recounting the dangers of training with the Sticky Bomb [37]

According to a War Office training pamphlet dated 29 August 1940, the sticky bomb should be regarded as a portable demolition device which can be "quickly and easily applied". [13] The sticky bomb was thought to be effective against armour of up to one inch (25 mm) thickness and was suitable for use against "baby" tanks, armoured cars and the vulnerable points on medium and heavy tanks. It could be dropped from an upstairs window or applied in place by hand, with sufficient force to break the glass creating a greater area of contact. It could also be placed first and then pulled out by means of a length of string. [13]

"A section of the Royal Durban Light Infantry used these bombs to great effect in what amounted to a battle between men and tanks. The South Africans, armed only with a Bren-gun, a Spandau-gun, a tommy-gun, and anti-tank rifle, sticky bombs, and hand grenades, took on an enemy formation consisting of 28 tanks which was advancing in "W" formation against the position that the section was holding. The South Africans waited until the leading tank was 10 paces away and then pelted it with sticky bombs, setting fire to it and forcing out its crew, who were all shot down. Four tanks were dealt with in this fashion and 28 Germans were killed." Men Versus Tanks – The Times. [38]

Macrae credits the Australian Army with developing the technique of applying a sticky bomb directly onto a tank instead of throwing it from a relatively safe distance. [35] Since the bomb used a blast effect, it was safe to do this and walk away provided only that the bomb's handle was pointing away from the bomber – the handle would be shot away from the explosion "like a bullet." [35] Macrae gives no date for the development of this tactic. Macrae confirmed that placing the bomb rather than throwing it gives better adhesion and allows thicker plates to be penetrated. [28]

By July 1941, 215,000 sticky bombs had been produced. Of these, nearly 90,000 had been sent abroad to North and South Africa, the Middle East and to Greece where they did useful service. [39] The remainder were stored at Ordnance Depots or distributed to army and Home Guard units. [39]

The grenade was first issued in 1940 to Home Guard units, who appeared to have taken a liking to it despite its flaws. [40] Although the Ordnance Board had not approved the grenade to be used by regular army units, a quantity were provided for training purposes. [16] However, a number of sticky bombs did find their way to British and Commonwealth units participating in the campaign in North Africa and were used as anti-tank weapons. During the Afrika Korps advance towards the town of Thala in February 1943, they accounted for six German tanks. [41]

They were also issued to units of the Australian Army, who used them during the Battle of Wau [42] and the Battle of Milne Bay. [43] They were used by various allied units on the Anzio Beachhead, namely the First Special Service Force, who obtained them from the British. A large number were also supplied to the French Resistance. [44]

Recognition

In 1947, the Royal Commission on Awards to Inventors considered claims from Macrae and from the managing director of Kay Brothers. Macrae's legal representative was Edward Terrell – himself a wartime inventor. [45] At the time the crown opposed granting an award; when Macrae was asked what elements of the sticky bomb he claimed to have invented, he replied "I am claiming no invention; I merely claim the development of the bomb, which was my job." [46] [ verification needed ] However, in 1951, the commission recommended that Macrae should receive an ex-gratia payment of £500 (equivalent to £16,700in 2021) and Norwood received £250 (equivalent to £8,400in 2021) for his contribution. [45] [47] [48]

Users

Users of the grenade included:

See also

Notes

  1. Where S.T. stands for Sticky Type. [2]

Related Research Articles

<span class="mw-page-title-main">Molotov cocktail</span> Type of improvised incendiary weapon

A Molotov cocktail is a hand-thrown incendiary weapon consisting of a frangible container filled with flammable substances and equipped with a fuse. In use, the fuse attached to the container is lit and the weapon is thrown, shattering on impact. This ignites the flammable substances contained in the bottle and spreads flames as the fuel burns.

<span class="mw-page-title-main">PIAT</span> Anti-tank weapon

The Projector, Infantry, Anti Tank (PIAT) Mk I was a British man-portable anti-tank weapon developed during the Second World War. The PIAT was designed in 1942 in response to the British Army's need for a more effective infantry anti-tank weapon and entered service in 1943.

<span class="mw-page-title-main">High-explosive anti-tank</span> Type of shaped charge explosive

High-explosive anti-tank (HEAT) is the effect of a shaped charge explosive that uses the Munroe effect to penetrate heavy armor. The warhead functions by having an explosive charge collapse a metal liner inside the warhead into a high-velocity shaped charge jet; this is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge. The shaped charge jet armor penetration effect is purely kinetic in nature; the round has no explosive or incendiary effect on the armor.

<span class="mw-page-title-main">Anti-tank warfare</span> Science and Technology tactics based around countering and immobilizing tanks

Anti-tank warfare originated from the need to develop technology and tactics to destroy tanks during World War I. Since the Allies deployed the first tanks in 1916, the German Empire developed the first anti-tank weapons. The first developed anti-tank weapon was a scaled-up bolt-action rifle, the Mauser 1918 T-Gewehr, that fired a 13.2 mm cartridge with a solid bullet that could penetrate the thin armor of tanks at that time and destroy the engine or ricochet inside, killing occupants. Because tanks represent an enemy's strong force projection on land, military strategists have incorporated anti-tank warfare into the doctrine of nearly every combat service since. The most predominant anti-tank weapons at the start of World War II in 1939 included the tank-mounted gun, anti-tank guns and anti-tank grenades used by the infantry, and ground-attack aircraft.

<span class="mw-page-title-main">Home Guard (United Kingdom)</span> 1940–1944 British Army auxiliary defence force

The Home Guard was an armed citizen militia supporting the British Army during the Second World War. Operational from 1940 to 1944, the Home Guard had 1.5 million local volunteers otherwise ineligible for military service, such as those who were too young or too old to join the regular armed services and those in reserved occupations. Excluding those already in the armed services, the civilian police or civil defence, approximately one in five men were volunteers. Their role was to act as a secondary defence force in case of invasion by the forces of Nazi Germany.

<span class="mw-page-title-main">No. 68 AT grenade</span> Anti-tank rifle grenade

The Grenade, Rifle No. 68 / Anti-Tank was a British anti-tank rifle grenade used during the Second World War and was one of the first operational weapons to utilise the shaped charge principle.

<span class="mw-page-title-main">Hawkins grenade</span> Anti-tank hand grenade/anti-tank mine

The Grenade, Hand, Anti-Tank, No. 75, also known as the "Hawkins grenade" was a British anti-tank hand grenade used during World War II. It was one of a number of grenades developed for use by the British Army and Home Guard in the aftermath of the Dunkirk evacuation. The grenade first appeared in 1942, and was designed to be more versatile than previous grenades, such as the No. 73 grenade and the sticky bomb.

<span class="mw-page-title-main">Blacker Bombard</span> Anti-tank mortar

The Blacker Bombard, also known as the 29-mm Spigot Mortar, was an infantry anti-tank weapon devised by Lieutenant-Colonel Stewart Blacker in the early years of the Second World War.

The No. 76 special incendiary grenade also commonly known as the A.W. bomb and SIP grenade, was an incendiary grenade based on white phosphorus used during World War II.

A limpet mine is a type of naval mine attached to a target by magnets. It is so named because of its superficial similarity to the shape of the limpet, a type of sea snail that clings tightly to rocks or other hard surfaces.

<span class="mw-page-title-main">No. 73 grenade</span> Anti-tank grenade

The No. 73 grenade, also known as the "Thermos", "Woolworth bomb", or "hand percussion grenade", was a British anti-tank grenade used during the Second World War. It got its nickname from the resemblance to a Thermos flask.

<span class="mw-page-title-main">Northover Projector</span> Grenade launcher

The Projector, 2.5 inch—more commonly known as the Northover Projector—was an ad hoc anti-tank weapon used by the British Army and Home Guard during the Second World War.

<span class="mw-page-title-main">British anti-invasion preparations of the Second World War</span>

British anti-invasion preparations of the Second World War entailed a large-scale division of military and civilian mobilisation in response to the threat of invasion by German armed forces in 1940 and 1941. The British Army needed to recover from the defeat of the British Expeditionary Force in France, and 1.5 million men were enrolled as part-time soldiers in the Home Guard. The rapid construction of field fortifications transformed much of the United Kingdom, especially southern England, into a prepared battlefield. Sea Lion was never taken beyond the preliminary assembly of forces. Today, little remains of Britain's anti-invasion preparations, although reinforced concrete structures such as pillboxes and anti-tank cubes can still be commonly found, particularly in the coastal counties.

Major-General Sir Millis Rowland Jefferis KBE MC was a British military officer who founded a special unit of the British Ministry of Supply which developed unusual weapons during the Second World War.

In military munitions, a fuze is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze designs can be seen in cutaway diagrams.

Colonel Robert Stuart Macrae TD was an inventor best known for his work at MD1 during the Second World War, his best known invention being the sticky bomb.

Ministry of Defence 1 (MD1), also known as "Churchill's Toyshop", was a British weapon research and development organisation of the Second World War.

Major Cecil Vandepeer Clarke MC (1897–1961) was an engineer, inventor and soldier who served in both the First and Second World Wars.

An anti-tank grenade is a specialized hand-thrown grenade used to defeat armored targets. Although their inherently short range limits the usefulness of grenades, troops can lie in ambush or maneuver under cover to exploit the limited outward visibility of the crew in a target vehicle. Hand launched anti-tank grenades became redundant with the introduction of standoff rocket propelled grenades and man-portable anti-tank systems.

References

  1. 1 2 OP1665 1946, p. 380.
  2. Postan, Hay & Scott 1964, p. 268.
  3. Churchill, Winston; Gilbert, Martin (1993). The Churchill War Papers: The ever-widening war, 1941. W. W. Norton & Company. ISBN   978-0-393-01959-9.
  4. 1 2 3 Macrae 1971, p. 18.
  5. 1 2 Macrae 1971, p. 19.
  6. Mackenzie 1995, p. 20.
  7. 1 2 Lampe 1968, p. 3.
  8. Macrae 1971, p. 12.
  9. Manchester Guardian, 21 February 1951.
  10. 1 2 Macrae 1971, pp. 122–123.
  11. 1 2 3 Macrae 1971, p. 124.
  12. Macrae 1971, p. 123.
  13. 1 2 3 Military Training Manual No 42.
  14. Macrae 1971, p. 125.
  15. Churchill 1949, p. 149.
  16. 1 2 3 4 5 Weeks 1975, p. 44.
  17. Mackenzie 1995, pp. 92–93.
  18. Macrae 1971, p. 98.
  19. CAB 120/372, Letter from Ismay to Prime Minister.
  20. CAB 120/372, Letter from Prime Minister to Ismay.
  21. Macrae 1971, p. 98; Ismay 1960, p. 172; Churchill 1949, p. 149.
  22. Macrae 1971, pp. 84–85.
  23. 1 2 CAB 120/372, A Short History of the ST Grenade.
  24. Ismay 1960, p. 172.
  25. WO 185/1.
  26. Churchill 1949, pp. 149, 246.
  27. Macrae 1971, p. 127.
  28. 1 2 Macrae 1971, p. 129.
  29. CAB 120/372, Letter to General Ismay.
  30. "BBC - WW2 People's War". Archived from the original on 13 November 2009. Retrieved 27 April 2009.
  31. OP1665 1946, p. 381.
  32. Weeks 1975, p. 43.
  33. Hogg 1995, pp. 239–240.
  34. Hogg 1995, p. 241.
  35. 1 2 3 Macrae 1971, p. 128.
  36. Macrae 1971, p. 130.
  37. "BBC - WW2 People's War" . Retrieved 29 April 2009.
  38. Times 6 August 1942.
  39. 1 2 CAB 120/372.
  40. Mackenzie 1995, p. 93.
  41. Watson 2007, p. 151.
  42. 1 2 Bradley 2008, p. 34.
  43. Brune 1998, p. 69.
  44. 1 2 Bull et al. 2004, p. 30.
  45. 1 2 T 166/15.
  46. Manchester Guardian, 23 May 1947.
  47. Manchester Guardian, 6 March 1951.
  48. UK Retail Price Index inflation figures are based on data from Clark, Gregory (2017). "The Annual RPI and Average Earnings for Britain, 1209 to Present (New Series)". MeasuringWorth. Retrieved 11 June 2022.
  49. https://www.canadiansoldiers.com/weapons/grenades/handgrenades.htm

Bibliography