Decoy

by Dudley Pope

  Finally the Croupier looked at his watch. ‘Time to give Jemmy a spell.’

  ‘Very well. He’d better have a quick course on this machine before he turns in. We’re going to have to put every signal Hazell picks up through the cash register. A week’s U-boat signals will be welcome at ASIU and Operations Room.’

  ‘Sobering thought, isn’t it?’ muttered the Croupier as he switched off the Enigma and gave Ned the manual to return to the safe, ‘that these signals –’ he waved the pages ‘– are being read by Doughnuts and his U-boats, and by us: the cuckoo in the nest.’

  Screaming alarm bells, as though they were trapped inside a bell with madmen hammering the outside, froze all three men for a moment. Hazell automatically shut off the receiver without realizing he did it, and threw open a row of knife switches. Ned grabbed the Triton manual and the Croupier shut down the Enigma lid.

  ‘Alarm,’ Hazell said. ‘Diving alarm.’

  By then Ned was already taking the half a dozen paces into the control room, arriving as the first of the oilskin-clad lookouts landed with a heavy crash at the foot of the ladder, his cork-soled boots acting like mallets on the steel plating, and cursing the second man who landed on top of him before he had time to roll clear. The two men, clumsy as bears in oilskins, looked as though they were wrestling as they tried to get out of the way, knowing two more lookouts and a lieutenant were due any moment. They were too slow to avoid the last two lookouts, although the four writhing and angry men managed to get clear while Jemmy stopped in the conning tower to secure the hatch.

  Ned, for once utterly out of his element, realized that he had in a few moments heard a complete sequence of orders, from the bridge and from Yon, who was now standing beside the two men operating the hydroplanes.

  First had been the alarm bells clattering through the ship, followed by Jemmy’s bellow of ‘Clear the bridge for diving!’ Then Yon had given orders, repeated on the telegraphs, to stop the diesels and disengage the drives. Then more telegraphs as Yon ordered the electric motors to be engaged with the propeller shafts, at the same time telling other men to close the diesel air intakes and exhaust ports.

  Then the engine room had signalled to the control room. ‘Ready to dive’, the other compartments in the boat had reported they were prepared for diving, and then the four lookouts had done their Marx Brothers act. And, as the hatch closed in the conning tower, Jemmy shouted as he spun the wheel to clamp it down hard on its rubber seal: ‘Flood! Take her down fast, Yon!’

  Ned stood fascinated but helpless, still holding the Triton manual, as Yon gave a string of orders, his voice loud now the fierce thunder of the diesels had stopped.

  Everything seemed to happen at once: there was a great roaring as air was thrust out of the ballast tanks by the sea rushing in; from aft came the ever-increasing whine of the electric motors and the vibration of the propellers turning, and the boat began diving, her bow dipping sharply.

  Above and outside the hull there were a couple of crashes as waves hit the conning tower, then the sea was silent as the boat slid downwards below the surface.

  That seaman, Ned worked out, is operating the forward hydroplanes and his dials show he has them hard down, forcing the bow to dive. Next to him was Ordinary Seaman Keene, responsible for the after hydroplanes, but a dial seemed to show he had them adjusted for ten degrees, which should mean the stern was lifting slightly and thus helping to force the bow down in a steep dive.

  Jemmy, obviously standing at the top of the conning tower hatch, shouted down: ‘How’s she going, Yon?’

  Yon glanced up at the moving needle on a dial.

  ‘Nicely, sir: sixty-five feet and descending.’

  ‘Take her down to a hundred and fifty and put Hazell on the hydrophones. Is the Commander there?’

  Ned stepped forward and looked up the hatch. ‘What is it, a Number 11 bus?’

  ‘Couldn’t be – they go in convoys. No, I think it was a destroyer. If she picked us up on her radar then we can expect a few hours’ depth-charging, starting any minute now.’

  ‘“Up Doppler!” eh?’

  Jemmy laughed and turned to ask the helmsman a question. Very soon, if the destroyer was turning to attack, they would hear her Asdic pinging. This underwater detection device was based on the same idea as a man in the dark judging the distance of the other side of a valley by shouting and measuring the time the echo took to return. The Asdic transmitted sound waves and, the instant they started bouncing back from an object like a submarine, determined the direction and, very approximately, the distance. It had two drawbacks. The major one was that it did not function if its ship was going at more than about fifteen knots, and the other that it became temperamental and confused when its distinctive ping hit cold layers of water, which acted more like a solid substance. Submarines and sub-hunters were, Ned reflected, probably the only people that knew the ocean was not a lump of water as cold at one hundred feet as it was on the surface. In fact it was like a giant multiple sandwich – between the surface and a hundred and fifty feet, the depth Jemmy had ordered, there might be half a dozen layers of water with differing temperature and salinity. And so on down to the sea bottom (about a mile below at this point).

  If the thermometer in the U-boat showed a particularly cold layer, Jemmy would hide beneath it, knowing the Asdic pings would bounce off. From bitter experience of hunting submarines with a destroyer, Ned knew that, just as the destroyer was sure she had the U-boat trapped, it usually found a cold layer and slid beneath. But now he was in a U-boat and about to be hunted, there would not be a cold layer for miles…

  Yon called up the hatch: ‘Hundred and fifty, sir. I’ll start trimming.’

  At that moment Hazell called: ’HE bearing red two zero, distant.’

  Yon relayed this to Jemmy, who clambered down the ladder into the control room. ‘Since we haven’t got any torpedoes, I can’t think why I stayed up there. Hydrophone effect at red two zero – yes, that’s him.’ He walked over to the small cabin next to the wireless room, where Hazell was now sitting in the doorway, wearing a headset.

  He pulled off one earphone and offered it when he saw Jemmy approaching, and the two men, the submarine commander crouching slightly and the hydrophone operator sitting, listened to the electronic underwater ear trumpet.

  Jemmy said to Yon: ‘Turn down the wick on those motors and quieten the ship. He may pass close.’

  The hum of the electric motors died down and there was something approaching an eerie silence in the boat.

  ‘What’s our heading?’ Jemmy asked in a loud whisper, and Yon repeated the question up the hatchway to the helmsman.

  ‘Oh nine oh, sir,’ he reported, and Jemmy nodded.

  It’s all a game of blind-man’s buff, Ned thought, with the hunter trying to guess which way the hunted is going. Once detected, a submarine can dive deeper but, as the hunter increases speed to get above to drop depth-charges, her Asdic does not register, giving the submarine a chance of swiftly turning one way or the other – or keeping straight on, gambling on what the hunter will do, since the hunter knows the tricks and might herself turn one way or the other.

  Ned noted that Jemmy had done what needed the coldest courage – keep straight on until the last minute, and then stop. The destroyer could this very moment be turning to port or starboard, depending on her commander’s guess about the U-boat’s tactic. But her commander might also reckon he was dealing with an experienced captain, who would try a bluff, or double or treble bluff, whichever it was.

  Ned looked at all the dials, gauges, piping and the unworried faces of Jemmy, Yon, the men at the hydroplane controls, and the three other men handling valves and levers in the control room (what had happened to the four Marx Brothers? Their oilskins were hanging up, and so were their binoculars, but the men, not needed, had vanished). No one seemed concerned that a
t any moment British or American depth-charges might be exploding so close that the cigar case shape of the U-boat would be crushed into tangled metal which would then slowly sink. That was an interesting point – in very deep water did a wreck eventually reach a depth where the water pressure was so great that by some basic law of physics, or hydrodynamics, or some other ‘ics’, it equalled the weight, so that it just stayed suspended, a metal tomb hovering at some level between the ocean surface and the ocean bottom for the rest of eternity, occasionally nudging other wrecks that had been similarly suspended since the first iron and steel ship sank? (This crushed U-boat would presumably have passed the hovering wooden walls of Nelson’s day at lesser depths: a whole Spanish plate fleet, sunk by some storm centuries ago, might be suspended there, like models hung by wires from a museum ceiling.)

  ‘HE green oh five, distant,’ Hazell reported.

  So the hydrophone effect, the arcane way of describing propeller noises, is passing ahead: the destroyer is passing across what would have been the U-boat’s course, and apparently not turning.

  ‘She’s not using her Asdic and I don’t think she spotted us,’ Jemmy said, and Ned realized that he was in fact making an informally formal report.

  ‘Very well: carry on as you think fit.’

  ‘We’ll wait half an hour,’ Jemmy said.

  ‘HE green two oh, fading,’ Hazell said.

  ‘We’re losing a good half-hour’s wireless signals from Doughnuts,’ the Croupier grumbled. ‘There might have been exciting orders for us to ignore, like “Sink the Ark Royal”.’

  ‘According to Lord Haw Haw she’s been sunk a dozen times already,’ Yon said, not taking his eyes off the dials above the hydroplane controls.

  ‘Perhaps Doughnuts is superstitious and reckons he’ll get her on the thirteenth try,’ Jemmy said.

  ‘No point,’ the Croupier commented gloomily. ‘Old Goebbels has sunk her so many times on the German wireless now that if any Ted does manage to sink her, he won’t get any credit.’

  Ned began laughing to himself. ‘Just imagine – say one of Goering’s favourite pilots sunk her, but Goebbels refused to broadcast the claim because he’d already reported her sunk so often. Old Fatty Goering would go mad!’

  ‘HE effect ceased altogether,’ Hazell reported, sounding rather disappointed, like someone who has run out of counters and has to quit the game.

  Jemmy glanced at his wristwatch. ‘When is dawn?’

  The Croupier flipped through the almanac on the chart table. ‘Two hours almost exactly.’

  ‘Damnation take that destroyer,’ Jemmy said. ‘I want the batteries topped right up so we can get a decent day’s run submerged.’

  ‘You don’t want to chance running on the surface in daylight?’ Ned asked.

  Jemmy twitched, the first Ned had noticed for several hours. ‘I’d sooner be watching ducks patrolling the Serpentine, but their Lordships gave me this toy to play with. So it’s up to you, sir.’

  The ‘sir’ was the unspoken acceptance that Ned was the senior and in command: if Ned wanted full ahead on the surface, Ned would have it: if Ned wanted an underwater run, just pass the word.

  Ned went over the arguments again. On the surface they could manage seventeen knots. Yon had worked out that they had enough fuel to reach the UK on the surface. So seventeen knots times twenty-four hours meant four hundred miles a day. With under two thousand miles to go, that meant five days. But it would be madness to spend the last two days on the surface – Coastal Command would be queuing up to attack. Three days and nights on the surface meant 1,200 miles covered, with eight hundred to go. Then running surfaced at night and submerged by day would give two hundred surfaced plus perhaps fifty submerged – just over three days to cover the last eight hundred miles. Three surfaced and three half and half meant six days, probably seven, before they reached the UK. Two days to pass the word, the manual and the cash register to London, two more days for the BP folk to get to grips with it. So it would be eleven days or so before BP was reading Doughnut’s signals with the Triton manual, a dozen altogether before the Admiralty had its U-boat plot brought up to date, and fourteen before any convoys would be getting signals diverting them from U-boat concentrations. That was assuming that Hazell continued intercepting signals from U-boats reporting their positions to Doughnuts, so the wireless log would give the Admiralty six days of positions.

  Yet a week in the Battle of the Atlantic at this stage was a long time, and furthermore Captain Watts had no idea that in the meantime a Mark III and the Triton manual were heading for him at whatever speed the circumstances would allow. Two weeks’ merchant ship losses could amount to…he remembered Watts’ grim face when he said the Admiralty reckoned at least a million tons of shipping a month would be torpedoed in the Atlantic when the Germans switched to the Triton code. A million tons… Take five thousand as an average size: that meant two hundred ships, which in a thirty-day month meant an average of six and a half a day. Thirty deck and engineer officers and seamen and twenty DEMS gunners to each ship…roughly 325 men dying each day.

  It was an interesting mathematical problem if your blood ran cold and calm enough. A straight surface run except for the last couple of days still meant a six- or seven-day voyage, plus seven days before BP and the Admiralty could light up the Blackout. Fourteen days meant ninety-one ships sunk and 4,550 men killed, wounded or trying to survive. That was the best he could do – assuming that this U-boat reached the UK safely, and that was almost an absurd assumption.

  But a complete run surfaced at night and submerged by day would take – Ned quickly worked out a rough total, based on 250 miles in twenty-four hours. That was two thousand miles divided by 250 miles in twenty-four hours…eight days, say nine. Plus seven more while the Mark III and manual went through the machinery. Sixteen days meant one hundred and four ships sunk, carrying an average of 5,200 men.

  So the choice was either a wild dash on the surface taking six or seven days, or a half and half lasting eight or nine. Which meant ninety-one ships lost compared with one hundred and four.

  He shook his head impatiently: he was standing too close to the problem. Seventy, eighty, ninety, a hundred ships – to save them by a surface run meant risking (indeed, almost ensuring) that this U-boat would be lost. What were those losses compared with getting the cash register and manual back safely, and saving (at the present rate of sinkings, although they would increase) nearly 2,400 ships a year? There was no choice, really.

  ‘Surface while we’re in the Black Pit. Then we’ll think again,’ Ned said finally to Jemmy, who realized that some struggle was going on in Ned’s mind. ‘We’ll make the last bit submerged in daylight.’

  The Black Pit was a broad band of the Atlantic stretching from south of Greenland down to the Azores which was out of range of Coastal Command planes flying from bases in Britain and Northern Ireland, or from Newfoundland. Although every citizen of Eire was fed by British ships travelling in British convoys, she refused to let British warships or planes use any of her ports or airfields, with all the logic of a drowning teetotaller refusing a lifebuoy hurled by a drunk.

  Jemmy nodded but the Croupier said questioningly: ‘It’s not worth taking a chance, Ned?’

  Ned shook his head. ‘For the sake of a few days? Listen, we’ve got what we came for and what the PM, Admiralty, BP and the Flat Earth Society are waiting for with bated breath. My sums here–’ he tapped the signal pad on which he had been doing his calculations ‘–show we must be losing an average of at least six and a half ships a day. But weigh that against a projected nearly 2,400 ships lost a year: a million tons a month the moment we lost Hydra.’

  ‘’S’right, guv,’ the Croupier drawled.

  ‘I’m in no rush,’ Jemmy said. ‘I just don’t like sleeping alone any more than Joan does. But neither of us wants to see me knocked off in a Ted U-
boat marked down as some frigate’s “probable”.’

  Ned nodded sympathetically: Joan was far too full of life to be left to sleep alone, and she was the only person who stood any chance of curing Jemmy’s twitch. As Jemmy always maintained, sex outdoes psychiatry every time.

  Jemmy looked at his watch and raised his eyebrows. ‘The half an hour is up. Permission to surface, sir?’

  ‘Carry on,’ Ned said, and turning to the Croupier asked him: ‘Would you make a copy of the main part of the Triton manual and keep it in your pocket sealed up tight in a knotted French letter?’

  ‘Yes. Although this volume is only current for three months and I’m not a cipher expert, I think it’ll tell the BP boffins enough to let them go on busting it. Shall I make an extra copy for you?’

  ‘As many as you can find carbons and FLs for. Jemmy, me, Yon, Sergeant Keeler, Hazell…if things go wrong surely one of us will survive.’

  ‘It’ll give me something to do. This is going to be a long trip and I didn’t bring any books.’

  Jemmy was standing at the entrance to the hydrophone cabin. ‘Any HE, Hazell? Take your time and turn that ear trumpet nice and slowly.’

  He looked round the control room and saw that Yon was not there. ‘Pass the word for Mr Heath.’ The oilskins and binoculars hanging on their hooks jogged his memory. ‘And pass the word for duty lookouts to come to the control room.’

  Yon came through the circular hatch which could shut off the whole after part of the boat in a watertight section. He had found a clean pair of engineer’s overalls and the German eagle, wings outspread, was still sewn on to the right-hand side.

  ‘How about this?’ he said. ‘You will address me as Oberleutnant, otherwise I shall sulk.’

  ‘Jawohl!’ Jemmy said and turned back to Hazell. ‘Well?’

  ‘No HE, sir: all round search. Just the fishes out there, nibbling the weed that’s grown on our hull.’

  Jemmy rubbed his hands together cheerfully and took down an oilskin coat. ‘Must get a supply of towels: these bloody jackets let the drips get down your neck.’ As soon as he had wriggled into the coat and speculated about the weather on the surface, he said to Yon: ‘Wish I could get used to this German routine. I can’t see any advantage in having the skipper up there in the conning tower and the rest of you down here in the control room.’