Cockleshell Heroes: the real story of WW2's Operation Frankton

Their mission was to paddle six two-man canoes, under the winter-thick cloak of darkness, up a 70-mile-long estuary

Their mission was to paddle six two-man canoes, under the winter-thick cloak of darkness, up a 70-mile-long estuary over three consecutive nights, penetrating into possibly the world’s most heavily guarded port, where they would attach limpet mines to strategically selected ships and then retreat. But not back to the submarine – that would be long gone. “How do we get back home, sir?” One of the men asked.

“You walk.” Hasler told them. Across occupied France, over the Pyrenees into neutral Spain, and then to Gibraltar. Hasler was serious. The prospect of a long life never looked so remote. They couldn’t even speak French.

What was Operation Frankton?

Combined Ops, under Lord Mountbatten, had decided that these men – along with their semi-collapsible Mark II ‘Cockle’ canoes – were the answer to the pressing ‘Bordeaux Problem’. Desperately over-stretched, Britain was increasing aware that ships from Asia were routinely outrunning their submarines and destroyers, reaching Europe packed with materials crucial for the Third Reich’s war effort. Many ended up in the well-protected port of Bordeaux on the massive Gironde Estuary.

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To win the Battle of the Atlantic, Churchill needed this problem sorted, but resources and manpower were desperately short. The Admiralty considered Bordeaux too far up the Gironde estuary to be a realistic target for their boats, and the RAF feared aerial bombing would cost too many French civilian lives, turning public opinion against the Allies.

Whitehall had to be inventive – that’s when they remembered a rejected concept put forward by a resourceful, if eccentric, Royal Marine named Hasler. He’d proposed engaging the enemy with canoe-based commandos. In late 1941, with the outlook on the Atlantic darkening daily, his plan suddenly seemed much more attractive.

Hasler was invited back to Whitehall, interviewed by Mountbatten and given his own unit to build and train, but it wasn’t until 21 September 1942 that he found out what they were training for.

After a briefing about the blockade busters hiding out in Bordeaux, Hasler devised a fully fleshed-out plan overnight. Mountbatten made just two changes, increasing the number of canoes from three to six (“In case of accidents”) and insisting that Hasler himself remain behind, as he was too important to risk with an active role in the mission. The Major made an impassioned appeal, stating his case for going, and Mountbatten relented.

After several more weeks of intensive training around Portsmouth, sometimes at night, Hasler handpicked his attack squad. They were split into two divisions, each containing three two-man boats with specified targets to hit once in position.

In Division A, Hasler would be joined by Corporal Bill Sparks in a canoe called Catfish, Corporal Albert Laver and Marine William Mills were in Crayfish, and Corporal George Sheard and Marine David Moffatt would paddle Conger. B Division placed Lieutenant John MacKinnon with Marine James Conway in Cuttlefish, Sergeant Samuel Wallace and Marine Robert Ewart in Coalfish, and Marine William Ellery and Marine Eric Fisher in Cachalot. A 13th man – Marine Norman Colley – was taken as a reserve.

The operation begins

HMS Tuna surfaced a couple of miles off the French coast at 19:17 on 7 December 1942. Between 19:36 and 20:22, five cockle canoes were winched over the edge of the submarine, each containing two camouflaged commandos, a small amount of food and clothing, some spare paddles and eight limpet mines. Lieutenant-Commander Dick Raikes, Tuna’s skipper, described them as “magnificent black-faced villains”. Blondie Hasler said he’d be back in March and told Raikes to book a table for lunch at the Savoy for 1 April.

The sixth canoe, Cachalot, was snagged and tore while passing through the hatch. Despite tears of protest from Fisher, Hasler ordered them off the mission. Colley was told he wasn’t required either, and the ten remaining men paddled into the night, towards an estuary mouth bristling with enemy boats and lethal defences manned by thousands of Germans.

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Most of the men had begun canoeing as rank amateurs just five months previously, and the sea proved their greatest enemy. Two hours in, they hit the first of three tidal overfalls – patches of dangerously agitated water caused when tides collide over shallow spots – which hadn’t been marked on their maps. For all his planning, knowledge and skill, these took Hasler by surprise. The result was disastrous.

Suddenly, they were fighting utterly unpredictable metre-high waves. Screaming instructions about keeping the boats’ bows pointing into the water, Hasler punched though with Sparks in Catfish. Crayfish, Conger and Cuttlefish all followed, but Coalfish disappeared.

The second overfall was worse still, with even higher waves. Conger capsized, throwing Sheard and Moffatt into the brine. Unable to right the stricken canoe, the team scuttled it and towed the two freezing men through the remaining tidal rush and into the estuary, where they were taken as close to shore as possible and told they’d have to swim for it.

It was, by now, impossible for the commandos to reach the east bank before dawn as planned, and they were forced to paddle very close to several anchored enemy boats. They split up to avoid detection, but once the danger had passed, Cuttlefish failed to re-join the group.

In just ten hours, Hasler’s task force of 13 had been whittled down to four. Shattered, the remaining men – Hasler and Sparks in Catfish and Laver and Mills in Crayfish – pulled into Pointe aux Oiseaux to rest for the day. They were discovered by sympathetic French fishermen at daybreak, who pointed out a safer hiding spot and later returned with food.

Hasler led his depleted team up the estuary over the next three nights, resting during the intervening days at Port des Callonges and then l’Île Cazeau. Shortly before dawn on 11 December, the four men pulled Catfish and Crayfish into the reeds at Bassens Pontoon Pier, just shy of 2 miles from Bordeaux.

At 21:15 that night, Hasler and Sparks paddled Catfish into Bordeaux and placed eight limpet mines on four ships on the west bank. At one stage, a boat sentry shone a flashlight directly commandos froze and the camouflage worked. Meanwhile, in Crayfish, Laver and Mills crossed to the east bank, directly opposite Bassens, where they placed their charges on two boats.

The men had six hours to get away before the charges began to go off. Purely by chance, the two teams met on l’Île Cazeau, from where they paddled together to St Genes de Blaye, landing 400 metres apart and scuttling the canoes. Yet it was nature, not Nazi defences, that proved most problematic for the unit. The explosions – music to the men’s ears – began at 03:50 and continued for hours. By this stage, they had again split into two teams and were travelling overland, using silk maps. They had a choice: move at night, wearing uniform in the hope that, if caught, they’d be treated as prisoners of war; or pretend to be civilians and travel during daylight, knowing they’d be shot as spies if apprehended.

Hasler and Sparks wore uniforms for two nights, before donning civilian attire given to them by friendly French farmers and villagers, who also supplied them with food and sometimes shelter.

At Ruffec, they expected to be met by the French Resistance, but no one was waiting. Serendipity led the fugitives to Café des Sports, a restaurant run by sympathetic owners, who put them in touch with the local Resistance. They were fed into the ‘Marie-Claire’ escape line, organised by English woman Mary Lindell. This network saw Hasler and Sparks safely to Lyon, then Marseille, Perpignan and finally Céret, from where they trekked over the Pyrenees to Banyoles in Spain and reached the British Consul in Barcelona.

Having spent months in each other’s company in the most extraordinary circumstances, the two men were finally separated for the last part of their journey. Sparks sailed back to England from Gibraltar, while Hasler was flown back from Madrid – arriving in April 1943 – just in time to meet Lieutenant-Commander Raikes for lunch at the Savoy.

What happened after Operation Frankton & what did it achieve?

Strategically and militarily, the mission’s achievements were meagre. The boats bombed were all empty, and they only sank a few feet before coming to rest on the shallow bottom of the harbour – all were quickly back in use.

Worse, unbeknown to Hasler or his Combined Ops’ superiors, the Special Operations Executive – a diffferent and, in some respects, rival Whitehall department – had a team of agents on the Bordeaux docks at exactly the same time.

This unit was scouting for an operation to blow up a number of boats at a more strategically advantageous juncture, but instead saw all their reconnaissance devastated by Hasler’s mines.

However, the Cockleshell Heroes blew a hole in German confidence that wasn’t as easy to patch as their boats. And the horror of so many dedicated men giving their lives virtually in vain because of inter-department factionalism galvanised Whitehall to sort itself out. The departments came together to ensure such doubling of effort, resources and risk taking never happened again and, within a couple of years, all three forces and the secret services pulled together to extraordinary effect in the planning and execution of D-Day.

This article appeared in the June 2015 issue of BBC History Revealed and was updated in December 2022