Paddy Ashdown's Cockleshell Heroes: 'an exclusive extract Late afternoon, Hasler came into Tuna's control room to find out how things were going. "It's all OK now," Raikes said. I'll put you ashore at 1930 if these damn patrol boats keep out of the way and we don't get blown up by the RAF mines. During the hours that followed, Hasler grabbed what opportunities he could to use Tuna's high-powered periscope to investigate the coast to the north along which he would be paddling that night. Tuna's crew had other matters than navigation to worry about. Those "damned" RAF magnetic mines were, of course, constantly at the back of their minds - but now there were enemy aircraft to contend with, too. An entry made in Tuna's log notes, laconically, "intense air activity" and lists the aircraft flying over them: Arados, Ju88s, Me109s, Me110s and Dornier flying boats. There was one aircraft, high above Tuna that afternoon, that she almost certainly did not see - and need not have worried about. At 1315 a lone, unarmed blue-painted Spitfire passed from south to north over Bordeaux and the Gironde, its high-definition camera whirring busily. The aerial photographs were rushed to the air interpretation unit at RAF Medmenham, Buckinghamshire, where they revealed that there were a dozen high-value targets in the Bordeaux docks, waiting for Hasler. It also showed four or five of the small minesweeper-type vessels used to patrol the estuary, heading north for Le Verdon and the mouth of the Gironde. Seven more enemy aircraft were sighted by Tuna that afternoon. With sea conditions reported as "oily calm with a long swell," it seems a minor miracle that none of these spotted the dark shadow creeping up the coast towards the gates of the great German maritime fortress. Throughout these tense, blind hours as Tuna slipped north through the local fishing fleet and past the RAF minefield, hearing was her crew's most important sense ­ - their sole means of detecting danger. There was absolute silence on board. Raikes gave his orders by hand signals. Robbie, Tuna's hydrophone operator, sat with his hands clasped over his headphones; listening, assessing every tiny vibration of sound. Sifting for the first tiny "dub dub dub" of propellers; or the rhythmic thumping of a diesel engine; or - most feared of all - the "ping-ping-ping" of a warship's sonar beam probing for them through the dark layers of the ocean. At one point something metallic bumped down their port side and everyone's back ran cold as they held their breath for the explosion that would blow them to kingdom come. But it never came and they relaxed again ­ - for the moment. At about 1500, Hasler's team prepared and packed the canoes. After an evening meal they then dressed, each man ticking off the other against a checklist of equipment. This included long woollen pants, over which went stockings and battledress trousers. On their feet were thigh-length waders. Under the waders, their commando daggers were strapped to their left thighs. On their top halves they wore woollen vests, a woollen shirt, a roll-neck sweater, a .45 Colt automatic in a holster and a life jacket. Over all this they put their rubberised and camouflaged "Cockle suits." An elasticated skirt sewn on the suits could be hitched over the edges of their canoes to make a waterproof seal. Finally, each man hung around his neck a lanyard to which was attached a seagull bird-call to communicate with each other. Once they were dressed and checked, Tuna's fore-ends were cleared of all clutter that might impede the unloading of canoes and the hatch clips were greased for easy and silent opening. Darkness fell at 1755, and Raikes continued squeezing his way north between the RAF mines. Aboard Tuna they switched to red lighting to enable eyes to grow accustomed to the dark. Raikes must have felt some relief now that, with the advent of darkness, he could forget the problem of aircraft and concentrate solely on getting his boat the last few miles to the drop-off point. Suddenly, Robbie, the hydrophone operator, whispered urgently. "H.E. ['Hydro Effect"] contact - propellers!" Silent routine. Stop all machinery. Raikes's calm voice echoed softly from the intercom around the boat. Range eight miles. Diesels," Robbie reported. Tuna tipped upwards, levelling out at 40ft. Looking through the periscope, Raikes saw a small patrol boat moving from the mouth of the Gironde. Down periscope - 70ft. Tuna sank silently back down again. Now they could all hear the methodic, probing ping of the patrol boat's sonar raking the seabed around them. Five minutes dragged by. The patrol boat was two miles away - not close enough to detect Tuna but too close for comfort. "H.E. fading away," Robbie reported to quiet relief. Raikes made another sweep with the periscope. At 1952 he was satisfied that Tuna was in the right position. Making a last check through his periscope, Raikes saw exactly what he had hoped not to see - the armed German trawler was now patrolling the estuary on a line that cut precisely across his point of disembarkation. If he was to avoid the enemy, he would have to change the drop-off point. But that would mean a new approach and new, unknown hazards. Raikes decided he had to take the risk. Positioning Tuna as close to the coast as he dared, he turned her stern towards the trawler ­ - which at this stage was 5,000 yards away - so as to present the smallest visible target to her. Then he gave the order: "Blow main ballast - stand by to surface," followed two minutes later by: "Stop main engines." Raikes, Tuna's pilot Gordon Rowe and two lookouts raced up to the bridge even before the submarine had fully broken surface. The sea's surface was flat calm and the night was very clear and very cold. Rowe reported he could see the enemy trawler but that otherwise, the horizon was clear. Major Hasler to the bridge. Raikes's voice came quietly down the bridge voice-pipe into the control room below. Hasler was standing on the bridge a few moments later. "Beastly clear night," commented Raikes. But looks all right for your launching. We can see the patrol boat there, but I don't think he can see us. Do you want to start? Hasler paused to look at the thin line of the French coast and listen to the sound of the surf thundering on the beach some two miles away. "Up canoes," Raikes called softly down the voice-pipe. The time was 1936. The attack stage of Operation Frankton had begun. As the two men stood watching the preparation, Hasler suggested that when he got back home in, he estimated, three months, they should meet for dinner. "Book a table at the Savoy on April 1," he instructed Raikes. No, I won't! Not April 1! I'll book a table on March 31 or April 2," Raikes replied. Well, I'd better get along and look after my own canoe. Thanks for everything you've done on our behalf. Well, cheerio, old boy. See you before long," Raikes replied, and the two men shook hands.