Lead up to, and including D-Day

ML1085 joined a fleet of small craft numbering around 350 strong to clear the channels during the lead up to DDay, their task was simple, clear the sea lanes for the beach assault ship and vessels to the staging areas, and then onwards to the beach heads themselves! The vessels may have been small but the task certainly was not. Eleven main shipping lanes were cleared for the larger ships to approach the staging areas, and then the approaches from there up to Utah, Omaha, Gold, Juno and Sword beachheads were cleared for the landing craft to take the troops tanks and other equipment ashore.

They started the night before on June 5th as the cover of darkness fell they progressed further towards German held beaches, they made way in a triangular formation with the HDML’s ML1085 amongst them going first over the mines. With their shallow draft they would be least likely to contact a mine, if they were unlucky enough to pass directly over one. A few were not so lucky, and some HDML’s have struck mines in this way, with only one known to be lucky enough to survive back to harbour, with her bow blown off up to the chart house she limped home, going astern and the crew pumping the engine room bilge. However none of the 350 vessels were lost on DDay itself, a remarkable achievement and turn of luck in itself.

Following the HDML’s initial sweep wires, the larger fleet trawlers were provided with relative safety, to then fan out behind each other in what was known as a G formation. They then swept broader and deeper for the coming task force. Following on from the sweepers were two pairs of danlayers, two to mark each side of the channel, with a further two laying extra where faulty danbuoys were identified.

The vessels that achieved this were equipped with light sweeping gear specially designed for the sweeping of magnetic and acoustic influence mines in shallow waters. A small number of LCTs were also similarly equipped. These flotillas were designated as follows.
British Yard Mine Sweeping (BYMS) Flotillas – 150th, 159th, 165th, 167th

YMS Flotillas (US) – Y1 and Y2

Motor Mine Sweeping (MMS) Flotillas – 101st, 102nd, 104th, 115th, 132nd, 143rd, 205th


By 0330 the ten channels had been swept by the Fleet Minesweeping Flotillas and shortly after the inshore areas parallel to the landing beaches had been swept by the BYMS, YMS and MMS ships. The Assault Flotillas were well into their passage to the Gold, Juno, Sword, Utah and Omaha Beaches to arrive by H-hour, and the bombarding squadrons of battleships, cruisers, monitors and destroyers were now ready to let loose the most concentrated firepower of naval ordnance ever experienced in the history of sea warfare against a land-based foe.

The minesweeping flotillas, having been given the honour of leading the way for the Allied Assault Forces, now moved northwards, either widening the channels or withdrawing to holding areas in what was to become, over the next few days, the ‘Trout Line’. This was a defence barrier set up around the Normandy anchorage to protect the ships from the multiple threats of E-boats, R-boats, human ‘Neger’ torpedoes and Linsen explosive motor boats. The ‘Trout Line’ itself was composed of LC(Guns), LC(Flak) and LC(Supply) set up in a continuous double line one cable apart. The minesweepers slotted in at 5-cables (half mile) intervals six miles seaward on each side and parallel to the beaches. Sword Beach, on the eastern flank, was particularly vulnerable to attack from the Le Havre area and enemy submarines were always a potential risk apart from the offensive threats above”.


With this dangerous task completed during the night an equally vital but more secret mission awaited ML1085 and a handful of other vessels. So secret that its particulars remained classified until the change in UK law bringing many particulars of war time stories such as the construction of the Bouncing Bomb and the codebreaking at Bletchley Park. To complete the deception the enemy radar station at Fecamp would need to be jammed to hide the coming task forces location. Although this would also alert the enemy to their presence, so to back up the deception a diversionary attack was also planned. So ML1085’s crew along with only a handful of other ships approached the enemy coast as the cover of darkness grew ever shorter, switching on their radar jamming equipment, they then commenced a diversionary attack on the coastline at Fecamp. Along with other diversionary actions that morning they were successful confusing the German response into thinking it was only a few small raids being undertaken. They were so successful that when they realised it was a full invasion, the Germans believed the real assault was occurring at the diversionary sites, and the attacks on Normandy were a diversion, a mistake that cost them several hours until their realisation.

Once the deception was complete ML1085 returned to her flotilla, and conducted convoy escort duties from the sea lanes up to the beach heads, providing anti submarine warning and protection, with her ASDIC system and depth charges. Her main task though reinforcing the beach heads by providing Anti Aircraft and extra beach support firepower with her Oerlikon 20mm cannons and her two twin mounted Lewis machine guns. With their shallow draft the HDML’s were able to approach close in to the beaches for this. This role she undertook for several days after DDay as the beach head was fully established, and its consolidation as the assault inland commenced.

The dan buoys laid on June 5th and 6th were replaced by June 7th with ocean light buoys by Trinity House.  In the opening phase of Operation Neptune covering June 5th and 6th, the 350 or so ML’s and other small craft had not only led through the fleet minesweepers and successfully swept the inshore areas, including the boat lanes from the transport areas and the beaches, which allowed for the initial attack. But they also cleared a sizeable area close to the beaches, as to press home the attack inland the Allies required constant supply. For this they needed a harbour, the artificial Mulberry harbours had been designed for this purpose, and could now be brought into shore and settled in the cleared waters for use.


Some of the ML’s were tasked with other vital roles such as the latterly named HMS Medusa (ML 1387 on DDay)  she and ML 1383 marked approach channels 3 &4 respectively in the mine swept areas. This vital role ensured that all shipping from battleships to troop ships approached and returned from the Normandy landing zones without fear from danger of the submerged minefield threat. They used the newly devised asdic repeater buoys to stay on station, a deviation of only a 100 yards or so could have devastating for the vessels involved and transiting through. Medusa survives to this day and is run by the Medusa Trust in her original wartime D-Day configuration.


Coastal Forces Control Frigates patrolled just outside the line sometimes augmented by destroyers thereby adding to defence in depth. The speed of the ships had to be tempered, knowing the potential to actuate the newish oyster mines.
Those 350 or so ships, from the Flotilla leaders to the Fairmile B MLs, had engaged in the most meticulously planned and well executed minesweeping operation ever undertaken and all had survived by the end of D-Day on June 6.

This narrative will close with a fitting tribute paid to all those involved, by the Naval Commander of the Western Task Force;

“It can be said without fear of contradiction that minesweeping was the keystone in the arch of this operation. All of the waters were suitable for mining, and plans of unprecedented complexity were required. The performance of the minesweepers can only be described as magnificent.”


Rear Admiral Alan Kirk USN

As the beach heads were consolidated the need for sea support at Normandy lessened, further along the coast the allies had the sights on a new objective and a new tasking for ML1085.

With the success of the diversion at Fecamp this tactic was to be used again, this time though a military attack was already underway but stalling, it was time for an sea based attack on and invasion of Cherbourg, the proper harbour that the Allied forces so badly needed. Again ML1085 found herself part of a Naval task force, again it was a diversion, but this time the enemy were more than prepared. Upon sighting the Naval force they brought all of their heavy firepower in the Town and Port to bear down upon the attacking vessels. The strength of the German barrage out to sea was so intense that ML1085 and her companions were driven away, many larger vessels were holed and had to retreat by the sustained fire. However they had pressed their attack under this onslaught for more than long enough, for as they fought off the sea attack, the Germans in their haste to prevent another invasion, had unwittingly left their rear defences and flanks less prepared for the invading allied Army, and so Cherbourg was captured relatively intact with its main armament all facing out to see where it was neutralised by the fleet, remaining resistance was eliminated by the 29th. Again it was the close support provided by the smaller craft which proved most effective, supporting the invading ground forces, able to fire up to 2000yds inland with their heavy calibre machine guns.




ML1383 Leaving Harwich harbour with HMS Curzon in the background ML1383 was with the 149th flotilla for DDay