German Magnetic Mine, dropped by parachute by He115 and He111 aircraft. Often called a ground mine because it does not float but lays on the sea bed.
In the weeks that followed the successful deactivation of the Magnetic Mine, countermeasures were devised. The technique of degaussing ships was developed where a vessel is demagnetizing with an electric coil, a copper wire running around the ship, to prevent it from triggering an enemy magnetic mine when sailing nearby.
LL (double L) minesweeping was developed where a pair of electric cables were towed parallel to each other on floats behind the minesweeper which emit a strong electric pulse generating a magnetic field which detonates magnetic mines.
Only two days before on the 20 November 1939, the day when the first Magnet Mine was deactivated, HMS Mastiff detonated a mine which the crew were trying to bring on board. As there was no point in bringing on board a Contact Mine it was almost certain they were trying to recover a Magnetic Mine. A specimen of which was urgently required to be examined and ways to combat this new menace developed. Six of her crew lost their lives in the attempt.
23 NOVEMBER 1939 to THE NEW YEAR. (Wildfire III, Queenborough, Minesweepers movements.)
From the 1 September 1939 until May 1940 eighty ships had been sunk by enemy mines, in the Thames Estuary and off the east coast of England, with the loss of some six hundred lives.
The Renascent, a Queenborough Minesweeper, formed part of an experimental flotilla in an attempt to find the means to combat the magnet mine menace. The remainder of the Queenborough Minesweepers laboured on without adequate means of sweeping Magnetic Mines.
During this time Minesweepers (Trawlers and Drifters) at Wildfire III, Queenborough would have been sweeping the sea lanes from Southend up as far as Harwich and from Sheerness around the North Foreland to Dover and beyond. They would have been sweeping in small groups of three or four vessels for moored contact mines. They would be accompanied by Danlayer Trawlers. The task of a Danlayer was to follow the minesweepers as they worked an area, and lay dans, marker buoys, which defined the area swept and made it obvious where the clear channels were.
With the commencement of 1940 bombing by the German Luftwaffe on shipping in Thames Estuary and East Coast intensified. As yet there were few barrage balloons and German planes would often make low level strafing attacks on British ships. Stuka Dive Bombers, with their sirens screaming would dive bomb British ships. Minelayers, moving in straight lines, unable to maneuver quickly were easy targets. But the Minesweepers were equipped with anti-aircraft guns and fought back.
In November 1940 the Stuka’s had one last crack at the shipping in the Thames estuary and were never seen in daylight again over England. Designed as a support aircraft for ground troops, they could neither fight or run and required fighter cover to operate over England.
Although the Stuka Dive Bombers were withdrawn due to their venerability to the faster British Spitfire, the pressure on British East Coast shipping by German aircraft would not diminish until Hitler attacked Russia on June 21, 1941.
It wasn’t until 28 march 1940 that the first Minesweepers equipped for magnetic minesweeping arrived at HMS Wildfire, Queenborough. The first operational LL Trawlers were the Lichen, Monarda, Tilly Duff, and Vernal.
Sadly, amongst the losses from enemy bombs in 1940 (1st November 1940) was the Queenborough Minesweeper the Tilburyness which was bombed and sank with of ten of her crew being killed. The Royal Eagle and the tug Salvo, both from Sheerness, courageously fended off other aircraft with anti-aircraft fire and rescued survivors.
During 1940 Minesweeping became paramount and the following Admiralty message was broadcast by the BBC.
“The admiralty needs a large number of fishermen to form the crews of additional minesweeping vessels. The age limit is 18 and 45, and volunteers should have if possible not less than one year’s experience in deep sea fishing vessels. “
The newspaper headlines at that time read, “2,000 men volunteer for Minesweeping, to man 200 drifters.”
By the end of 1940 alone over one hundred of these converted trawlers had been lost, mostly by Mines and others to enemy aircraft.
In the week 8th to 15th December 1940 the Luftwaffe returned again to the Thames Estuary to lay more magnet mines. Three hundred and fifty German planes from IX Luftkorps, each carrying two mines, dropped them by parachute. More than 175 of these fell inside the anti-submarine boom, which stretched from Sheppey to Shoeburyness. From this single Minelaying raid sixteen ships were sunk in sight of Sheerness. Seven ships were lost at once. Many of the mines were fitted with a delay mechanism and more ships were sunk in the week that followed.
By May the worst of the German mining offensive was over, but the Evacuation of Dunkirk was about to begin. Minesweepers from Wildfire III, Queenborough and vessels from Wildfire at Sheerness were to play a significant part in the Evacuation of Dunkirk.
Sunday 26th may 1940, 18.57 hrs. the signal “Commence Operation Dynamo” was received by Admiral Ramsey at Dover Castle. But before this date thousands of men and been bought back to England by the Royal Navy.
28 May 1940. A large number of vessels were sent from Sheerness and Queenborough to assist at Dunkirk. This was the same day the as first of the "little ships" left Sheerness and Ramsgate for Dunkirk.
In the day’s previous to this, hundreds of “little” ships from the Thames had arrived at Sheerness to be made seaworthy, provisioned and manned by Royal Navy personnel. It was here at Sheerness, when the first civilian boat crew volunteered to man their own craft on its passage to Dunkirk that the Legend of the Little Ships with their civilian crews was born.
Some Queenborough mine sweepers went right up the Dunkirk Beaches to take off troops. The remaining Queenborough minesweepers with others in the Nore Command, in addition to keeping the sea lanes open for the East Coast convoys, swept three passages through the minefields between Kent and Dunkirk. These would be swept and re-swept making them as safe as possible for the evacuation vessels.
JULY, AUGUST AND SEPTEMBER 1940. Many of the Queenborough vessels were patrolling the North Sea and the English Channel on Invasion Watch.
On 16 July 1940 Hitler issued Directive No. 16, Operation Sea Lion, the Invasion of Great Britain.
August 1940. The Enemy was building up for an invasion just across the Channel. There were large scale movement of barges which were being massed in European Ports. Moon and tide were favourable for a German Invasion of England between the 8th and 10th September 1940.
With the British Army’s withdrawal from Europe and the loss of its equipment, the British Army didn’t even have enough tanks, vehicles and weapons to equip two Divisions. Should the enemy get a foot hold in Britain, we would not be able to defeat them! It was imperative that the invasion fleet be destroyed at sea.
Of the thousand Armed Drifters and Trawlers, many of them minesweepers, at any one time a third patrolled the North Sea and Channel on patrol watch for invasion.
This continued until Sea Lion was postponed indefinitely on 17 September 1940 and the Invasion barges began to be removed from Channel Ports.
As the war continued new types of mines were introduced by the Germans and laid in the waters off the East Coast. In late September and early October 1940 a number of ships were lost to mines which were suspected to be acoustic mines.
The first acoustic mines were detected by the British in the Thames Estuary in October of 1940. These mines operated via a microphone which was set to react to particular sound signatures such as a propeller turning in the water.
On the 12 October 1941 a Harwich based minesweeper swept an acoustic mine. Next day the Harwich Mine Sweeping Flotilla swept six more acoustic mines.
Counter measures were quickly developed to combat these new mines and minesweeper were equipped with both LL and SA sweeping capabilities. LL (double L) is a pair of electric cables which are towed parallel to each other on floats and emit a strong electric pulse which generates a magnetic field which detonates magnetic mine. SA is Sweep Acoustic, a device similar to a Kanga Hammer which makes a loud thumping noise to explode acoustic mine.
Ships yards around Great Britain were building ships of every type at a rapid rate. Amongst these were the Motor Mine Sweepers (MMS). Motor Minesweeper were purpose built, wooden, shallow draft, minesweepers. The first of these MMS 1 and MMS 8 went to Wildfire III at Queenborough.
MOTOR MINESWEEPERS ARRIVING AT WILDFIRE III, QUEENBOROUGH 1941.
MMS 1, 8, 15, 16, 19, 25, 26 39 40, 41, 44, 45, 53, 59, 79, 68, 80, 82, 113.
(MMS 1, MMS 16 and MMS 80 were drafted overseas)
In the spring of 1941 purpose built MMS (Motor Mine Sweepers) were joining the East Coast Minesweeping Flotilla’s at a faster rate.
Throughout most of 1941 Queenborough Minesweepers were plying back and forth, clearing mines along the East Coast and keeping the sea lanes open. As always, there was the ever-present danger of attack from the skies by the Luftwaffe, attack from the sea by E-boats and the very real likelihood of detonation a mine with the loss of the vessel and crew.
Most of the time the job of minesweeping was monotonous as this account by a crew member demonstrates. “I’m an ex wireman on MMS 149. I worked out of Queenborough, Sheerness, sweeping around the Kent coast meeting Dover sweepers half way for 15 repeat sweep.”
Every once in a while that monotony was broken by a tremendous explosion when a mine was detonated.
On 11th March 1941 the Lend-Lease Act was signed into law by the Americans. The Lend-Lease Act allowed President Roosevelt to transfer military materials to Britain in exchange for 99 year leases on military bases and on the understanding that they would ultimately be paid for or returned.
Now, in addition to raw materials, military supplies began arriving in ships sailing along the East Coast Convoy routes to arrive in the Thames Estuary and on the London.
At 7.55am on Sunday 7 December 1941 Japanese aircraft attacked the American Fleet, moored at Pearl Harbour.
Hitler, convinced that the United States would soon beat him to the punch and declare war on Germany, declared War on the United States.
Somewhat to Britain’s relief, the United States, with its industrial might, was now an ally in the war against Germany.
The war materials which could be produced by the United States were of no use unless they could be bought safely across the Atlantic and landed in the great ports of Great Britain. For war materials to come flooding into the South East of England and the mighty port of London would require the sea lanes on the east coast and in the Thames Estuary to be kept open by our Minesweepers.
MOTOR MINESWEEPERS ARRIVING AT WILDFIRE III, QUEENBOROUGH 1942.
MMS 57, MMS 69, MMS 70, MMS 81, MMS 85, MMS 92, MMS 109, MMS 114, MMS 149, MMS 171, MMS 173, MMS 175, MMS 190, MMS 192, MMS 211, MMS 265, MMS 266.
(MMS 70, MMS 85, MMS 92, and MMS 114, were drafted overseas)
Shipping losses on the East Coast in 1942 had fallen by two thirds to those of 1941 thanks to the efforts of the Minesweepers.
January 1942. With the expectation that the German Pocket Battle ships Scharnhorst and Gneisenau and the heavy cruiser Prinz Eugen with a supporting fleet of Destroyers and E-boats would leave the Harbour of Breast and try to force a passage through the Dover Straights, Queenborough Minesweepers swept two new passages through the British Mine Barrier.
When the German Battle Fleet did break through the Channel, one of these passages was used by Sheerness and Harwich Destroyers to intercept and attack the Germen Battle Ships.
From June 1942 onwards the First of the BYMS’s (British Yard Mine Sweeper) joined the Wildfire III and East Coast Minesweeping Flotillas. BYMS were purpose built minesweepers, but these were built in the United States of America and transferred to Britain under the Lend Lease agreement. Built to the same design as the American Minesweepers which were known as YMS’s (Yard Mine Sweepers” the vessels bound for Britain were known as BYMS’s (British Yard Mine Sweepers)
On 19 August 1942 the ill-fated Dieppe Raid was launched. Before this could be undertaken, two lanes were cut through the German Minefields. It is known that Sheerness Destroyers took part in the Dieppe Raid but at this point it is not known if Queenborough Minesweepers were involved also.
MOTOR MINESWEEPERS ARRIVING AT WILDFIRE III, QUEENBOROUGH 1943.
MMS 267, MMS 269, MMS 216, MMS 137, MMS 294, MMS 295, MMS 287, MMS 282.
Shipping losses on the East Coast in 1942 had fallen to less for the whole year then in November 1940. Now minesweeping was mainly undertaken by purpose built minesweepers instead of fishing Trawlers and Drifters. Some of the Drifters and Trawlers were transferred to other duties such as supply vessels for the new Mansell Forts out in the Thames Estuary. Later, at Normandy, they would be used as water carriers, fuel carriers and smoke vessels.
German E-boats, (fast Torpedo Boats) always a problem, were particularly bad in 1943 making random appearances with devastating results.
On Tuesday, 6 June 1944 the Allies (Britain, the Commonwealth and the United States) returned to Europe. Operation Overlord was the code name for the D-day landings on Normandy. The Royal Navy side of the D-day landings was called Operation Neptune.
In front of all other ships were the Minesweepers. British Yard Mine Sweepers and Fleet minesweepers swept channels through the German minefields between the Isle of Wight and the Normandy Coast. The smaller Motor Mine Sweepers from Wildfire Queenborough, five hours before the invasion started were sweeping for mines in the assault area, making it safe for the war ships and landing craft.
When the battle commenced, under enemy fire, with shells falling, the Minesweepers worked on. When e-boats, explosive motor boats and mini submarines attacked the minesweepers worked on.
Minesweepers, including the Queenborough minesweeper, were a significant and crucial element in the success of the D-day landings.
The Motor Minesweepers involved were Motor Mine Sweeping (MMS) Flotillas – 101st, 102nd, (Nore Command), 104th, 115th, 132nd, (Nore Command), 143rd and 205th.
The men who went over the Normandy beaches were the bravest of the brave, but at the end of the first day they were physically, emotionally and mentally exhausted. Their ammunition was running low and much of their equipment had been lost. The enemy was expected to counter attack before the Allies could gain a firm foot hold on French soil. These troops urgently needed resupplying and reinforcing. While the first landing craft were rushing towards the D-day beaches, a huge armada had built up in the Thames estuary.
Proceeded by twenty Queenborough minesweepers and escorted by Sheerness war ships the second wave of assault and supply ships sailed from the Thames Estuary for the D-day beaches, arriving at high tide on D-day + 1.
This is what the D-day Landing Official Documents say about the “follow up” force,
The rapid build-up of our forces on the far shore after the assault is vital to the success of the operation.
Force “L”, its passageway swept clear of mines by Queenborough Minesweepers and protected by Sheerness War Ships was the immediate follow up taskforce. British and Canadian forces were reinforced and resupplied from the Thames and the American forces from the Bristol Channel.
As the Wildfire III, Queenborough MMS’s (Motor Mine Sweepers) and BYMS’s (British Yard Mine Sweepers) plied back and forth keeping the Normandy ship assembly area clear of mines or preceded the great convoys heading to the D-day beaches, the Trawler and Drifter minesweepers kept the East Coast sea lanes open.
Huge Armada’s of ships, convoy after convoy, left the North American shores, ventured across the U-boat infested Atlantic, journeyed around the north of Scotland to arrive in the Thames Estuary. Hundreds of “Liberty” ships, specifically made to transport war supplies across the Atlantic, rested briefly in the Thames Estuary safely behind the Thames Anti-submarine Boom, before continuing their journey on the Mulberry Harbours at the D-day beaches.
The enemy would do everything in its power to close the East Coast seaways and their mining offensive, by air and by sea was expected to intensified. Now more than ever the Wildfire III, Queenborough, Minesweepers had to keep the Thames Estuary, East Coast and Channel sea lanes open.
Magnetic mines were fitted with timers and once dropped could be set to activate in 24, 48, 72 or 120 hours. They could also be set not to respond until a number of ships had passed over them before they were armed. Minesweeper could, and often did, sweep a channel to have ships following behind in a “cleared” channel activate a “sleeping” mine which blew up sinking the ship .
The job of the Wildfire III, Queenborough Minesweepers was constant and never ending.
As the British, Canadian and American Armies moved northwards the Wildfire III MMS’s and BYMS’s moved up the coast with them clearing the minefields off the French, Belgium and Dutch coasts.
In October and November 1944 the Wildfire III, Queenborough Minesweepers gained high praise and many medals when they cleared the Scheldt Estuary of mines. Even before the fighting had stopped Queenborough Minesweeper had slipped by the German Batteries at night to begin clearing the approaches to Antwerp. This allowed the Port of Antwerp to be used to supply the British, Canadian and American armies who by then had greatly overextended supply lines.
The end of 1944 and the beginning of 1945, (November 1944 to March 1945) found the Wildfire III, Queenborough, Minesweepers working off the Dutch coast and clearing passages into Rotterdam, Yjmuiden and Den Helder.
Many of the commendations the crews of the Queenborough Minesweeper received concluded “and by so doing shortening the war.”
What the Wildfire III, Queenborough, Minesweepers achieved by clearing the ports of Rotterdam, Yjmuiden and Den Helder merits the highest praise, not only from a military point of view but for a humanitarian one. During the harsh winter of 1944-1945, after the failed attempt by the Allies to punch its way into northern Holland at Arnham (Operation Market Garden) a large part of the German-occupied Netherlands suffered from severe shortages of food and fuel. Dutch railway workers went on strike in support of Market Garden and the German military took control of the railway network and cut off food and fuel transports to the North-western part of the Netherlands. Over 20.000 people died of hunger.
Clearing the mines from the entrance of Rotterdam, Yjmuiden and Den Helder allowed humanitarian aid and food to arrive. The Wildfire III, Queenborough Minesweepers were amongst the first British ships to enter these ports where they found Dutch children who had been surviving by eating tulip bulbs and fed them with all the food they could spare.
In March and June 1945 Wildfire III, Queenborough Minesweepers swept the Elbe River opening up the Port of Hamburg and the Weser rivers opening up the Port of Bremerhaven. (both in Germany).
Again some of the first British ships to enter Hamburg fed the children. Les Jones, Asdic Operator on board the first ships entering Hamburg relates, "When we arrived in Hamburg there wasn't one brick standing on top of another. I was on guard duty and there were half a dozen dirty and hungry looking German kids on the dockside. The oldest could speak a little English and every time I walked past he said "Sir, have you bread sir." At first I ignored them. (This might sound a bit hard today but several months earlier a German submarine had sunk his ship, the Blackwood, killing 58 of his friends and shipmates.) Knowing some of the crew wouldn't be happy if he gave food to German children, he made a joke of it by cutting loaves of bread long ways and filling them with butter and jam. He gave a loaf to each of the children. But, he told us, some of the crew still didn't like it.
From May to June 1945 Wildfire III, Queenborough Minesweepers swept cleared the great Skaggerak Mine Barrier between Denmark, Norway and Sweden giving access to the Baltic.
With the surrender of Germany on 8 May 1945, the war did not come to an end for the Wildfire III, Queenborough Minesweepers.
On the 11 May 1945, two German E-boats flying the white flag crossed the North Sea. They were met off the Thames Estuary by British MTB’s and escorted them into Felixstowe. On board the E-boat was German Admiral Brauning with the charts of the German Minefields.
It was the job of the Queenborough Minesweepers, together with others, to sweep these minefields clear of mines and make the North Sea safe again.
These mines were laid in British waters by the enemy, usually at night. They were laid by minelayer ships, but usually by Destroyers or E-boats (fast German torpedo boats) and occasionally by submarines.
The British were also laying these mines off the Coast of Europe. The British also laid tens of thousands of these mines in a great mine barrier off the coast of Britain.
Minesweepers (Trawlers and Drifters) at Wildfire III, Queenborough from the commencement of World War Two in September 1939 to December 1939 would have been sweeping in small groups the sea lanes from Southend up as far as Harwich and from Sheerness around the North Foreland to Dover and beyond. They would have been sweeping for moored contact mines.
While we do not have a detailed record of all the Wildfire III vessels, we do know in general terms, what they were doing and when they were doing it.
SEPTEMBER TO NEW YEAR 1939 (Wildfire III, Queenborough, Minesweepers movements.)
World War One had taught the British the danger of sea mines and the importance of minesweepers. England’s survival during World War Two would depend on the success of the Minesweepers. If Hitler succeeded in closing the seaways leading to Britain’s major ports, we would lose the war. If the Minesweeper could keep the sea lanes open, there was a possibility Britain could survive. By June of 1940 Britain was alone, the rest of Europe had fallen, our military equipment abandoned at Dunkirk. If Britain could survive, with the aid of the Commonwealth and later the United States of America, the tide of war could be turned, and in time, the war could be won.
Britain desperately needed time to build up its defences, to build tanks and guns and ships. We needed the raw materials to do this and in the beginning, the raw material we needed most was coal. Today it seems strange that coal could be so important and that men would lose their lives delivering it. Trains could not do the job, they were needed for other things and trains simply could not deliver enough coal. We needed coal to warm our homes, to power our ships and our trains. Above all we needed coal for our power stations to produce the electricity. We needed to power for our munitions factory’s and our aircraft factory’s, to produce steel, to make ships, tanks and guns and planes.
At the commencement of WW2, it was clear that Wildfire, the Naval Base at Sheerness would not be big enough to accommodate the increasing number of vessels and in November 1939 a second base was established, a few miles away at Queenborough. This base was named Wildfire II. When an accommodation ship arrived in July 1941, the naval base at Queenborough was named after the Ship, HMS St. Tudno. When HMS St Tudno was transferred elsewhere, the Naval land base at Queenborough became WILDFIRE III.
In 1939 Britain had the biggest navy in the World, but it simply wasn’t big enough to protect the tens of thousands of merchant ships bringing goods and raw materials to our shores. Ships of every shape and size were pressed into service by the Royal Navy.
Even before World War Two started, ships suitable to be used as minesweepers were requisitioned by the Admiralty. These were mainly trawler and drifter fishing vessels. “Trawler’s, were the larger Ocean going vessels which fished with trawl nets (large bag shaped nets dragged along the sea bottom) “Drifter” were smaller fishing vessels using (curtain like) drift nets mainly in the North Sea. Both Trawlers and Drifters were sturdy, seaworthy vessels ideal for minesweeping and were requisitioned by the Admiralty to be used as Minesweepers.
When Trawlers and Drifters were requisitioned, often their crews would volunteer to come with them. The Captain was the senior officer on board, but often he would have with him an inexperienced officer who was training on the job.
Most Trawlers and Drifters were coal burners and large numbers of these had to be converted into war ships. Additional supports were added to strengthen the hull and decks to bear the extra weight of the guns and mine sweeping gear. Holds which were once used to store fish were fitted out as mess decks with tables, benches and bunks or provision to hang hammocks.
Few vessels had refrigerators so the galley was mainly stocked with tinned and dried food although, limited fresh food could be stored and potatoes were always available. Cooking was done on a coal burning kitchen range. Ex-fishing vessels manned by ex-fishermen could often supply themselves with fresh fish.
Below the bridge, a wardroom for a small number of officers (1 to 3) was constructed. It was furnished with bunks, tables, chairs and the safe, where money and confidential documents were secured. Rifles, required to sink mines and the ammunition for them was stored in a secure magazine beneath the mess deck.
There were no washing facilities for people or their clothes and washing was done in a bucket with hot water supplied from the galley.
When the weather was bad, washing cooking and most day to day activities became all but impossible.
Minesweeping trawlers were armed with an assortment of weapons, often left over from World War One, which arrived covered in a thick layer of grease. A 4 inch or 12 pounder was mounted on the forecastle, an Oerlikon (or a Borfor or 0.5 machine guns) was mounted aft and Lewis or Hothchkiss guns were mounted on the bridge wings.
Initially, Trawlers and Drifters were fitted with mine sweeping gear to clear Moored Contact Mines. This gear consisted of a long cable with a serrated edge to cut the Contact Mine’s mooring cable. In WW2 cable cutters, which the crew called Sharks Mouths, were attached to the minesweeping cable. On the end of the cable there was a float designed to move away from the minesweeper allowing a strip of sea to be swept. Once the Contact mines tether was cut and floating on the surface the Minesweepers crew would fire their rifles at it.
Hands on foredeck firing at a mine.
They were NOT aiming at the prongs on the mine to explode it. They were aiming at the body of the mine to puncture and sink it. A large explosion close to the minesweeper would be undesirable and dangerous.
A moored Contact Mine is what we all think of as the traditional sea mine. It is an oval shape mine with horns on the top, floating close to the surface of the sea, connected by a cable to a sinker on the sea bed. The horns are the firing points and contact with them activates the mine with devastating results.
When the horn is bent (not pushed in as you would expect) a sealed glass tube of acid inside breaks. The acid flows over the battery contacts and completes the circuit of the electric detonator.
TRAWLERS AND DRIFTERS.
WILDFIRE III, QUEENBOROUGH, MINESWEEPERS ACTIONS DURING WORLD WAR TWO.
British armed Trawler minesweeping in the North Sea.
The sea lanes marked in red are the main sea lanes swept and kept open by the Wildfire III, Queenborough minesweepers. This was done in team work with minesweepers from other minesweeping groups bases at Harwich and Dover.
The sea lanes marked in orange are the sea lanes swept and kept open by the Wildfire III, Queenborough minesweepers during the Dunkirk Evacuation.
13 NOVEMBER TO 23 NOVEMBER 1939. (Wildfire III, Queenborough, Minesweepers movements.)
During this period every Wildfire Minesweeper would have been desperately searching for one of the new German Magnetic mines. Not to destroy it, but to acquire it so it could be examined and counter measures devised.
On 13 November 1939 everything changed for the minesweepers with their tethered mine sweeping gear with which they swept for Moored Contact Mines.
On this date there was a large explosion under HMS Adventure near Tongue Light Vessel in the Thames Estuary, ten miles north of Margate. It was not known at that time but the Adventure had detonated the first magnetic mine. Twenty-four of HMS Adventure’s crew were killed and sixty-nine were wounded.
HMS Blanche was standing by when she too detonated a magnetic mine and was blasted aft. The sea flooded her engine room, her bridge was wrecked, two of her crew were killed and ten injured. Shortly after, while on tow, she sunk.
Over the next month fourteen more vessels were sunk in the same area. Normal minesweeping methods simply were not working.
On the night of 22 Nov 1939, a German plane was observed dropping something by parachute into the Thames Estuary, close to the Essex coast.
A search at daylight found that this was a magnetic mine which had landed in shallow water and was exposed at low tide. Lieutenant-Commander John G. D. Ouvry RN assisted by Chief Petty Officer Baldwin set to work disarming the mine with especially made brass tools. The first thing they discovered was that the mine was designed, not to float, but to lay on the sea bed which explained the non-success of the minesweepers in their efforts to secure a specimen.
A moored Contact Mine.
A "Sharks Mouth" cable cutter.