Ice Station Zebra Read online

  ‘Speed zero,’ Raeburn said.

  ‘120 feet,’ Swanson said to the diving officer. ‘But gently, gently.’

  A strong steady hum echoed in the control centre. I asked Hansen: ‘Blowing ballast?’

  He shook his head. ‘Just pumping the stuff out. Gives a far more precise control of rising speed and makes it easier to keep the sub on an even keel. Bringing a stopped sub up on a dead even keel is no trick for beginners. Conventional subs never try this sort of thing.’

  The pumps stopped. There came the sound of water flooding back into the tanks as the diving officer slowed up the rate of ascent. The sound faded.

  ‘Secure flooding,’ the diving officer said. ‘Steady on 120 feet.’

  ‘Up periscope,’ Swanson said to the crewman by his side. An overhead lever was engaged and we could hear the hiss of high-pressure oil as the hydraulic piston began to lift the starboard periscope off its seating. The gleaming cylinder rose slowly against the pressure of the water outside until finally the foot of the periscope cleared its well. Swanson opened the hinged handgrips and peered through the eyepiece.

  ‘What does he expect to see in the middle of the night at this depth?’ I asked Hansen.

  ‘Never can tell. It’s rarely completely dark, as you know. Maybe a moon, maybe only stars — but even starlight will show as a faint glow through the ice — if the ice is thin enough.’

  ‘What’s the thickness of the ice above, in this rectangle?’

  ‘The sixty-four thousand dollar question,’ Hansen admitted, ‘and the answer is that we don’t know. To keep that ice-machine to a reasonable size the graph scale has to be very small. Anything between four and forty inches. Four inches we go through like the icing on a wedding cake: forty inches and we get a very sore head indeed.’ He nodded across to Swanson. ‘Doesn’t look so good. That grip he’s twisting is to tilt the periscope lens upwards and that button is for focusing. Means he’s having trouble in finding anything.’

  Swanson straightened. ‘Black as the Earl of Hell’s waistcoat,’ he said conversationally. ‘Switch on hull and sail floodlights.’

  He stooped and looked again. For a few seconds only. ‘Pea-soup. Thick and yellow and strong. Can’t see a thing. Let’s have the camera, shall we?’

  I looked at Hansen, who nodded to a white screen that had just been unshuttered on the opposite bulkhead. ‘All mod cons, Doc. Closed circuit TV. Camera is deck mounted under toughened glass and can be remotely controlled to look up or round.’

  ‘You could do with a new camera, couldn’t you?’ The TV screen was grey, fuzzy, featureless.

  ‘Best that money can buy,’ Hansen said. ‘It’s the water. Under certain conditions of temperature and salinity it becomes almost completely opaque when floodlit. Like driving into a heavy fog with your headlights full on.’

  ‘Floodlights off,’ Swanson said. The screen became quite blank. ‘Floodlights on.’ The same drifting misty grey as before. Swanson sighed and turned to Hansen. ‘Well, John?’

  ‘If I were paid for imagining things,’ Hansen said carefully, ‘I could imagine I see the top of the sail in that left corner. Pretty murky out there, Captain. Heigh-ho for the old blind man’s buff, is that it?’

  ‘Russian roulette, I prefer to call it.’ Swanson had the clear unworried face of a man contemplating a Sunday afternoon in a deck-chair. ‘Are we holding position?’

  ‘I don’t know.’ Raeburn looked up from the plot. ‘It’s difficult to be sure.’

  ‘Sanders?’ This to the man at the ice-machine.

  ‘Thin ice, sir. Still thin ice.’

  ‘Keep calling. Down periscope.’ He folded the handles up and turned to the diving officer. ‘Take her up like we were carrying a crate of eggs atop the sail and didn’t want to crack even one of them.’

  The pumps started again. I looked around the control room. Swanson excepted, everyone was quiet and still and keyed-up. Raeburn’s face was beaded with sweat and Sanders’s voice was too calm and impersonal by half as he kept repeating: ‘Thin ice, thin ice,’ in a low monotone. You could reach out and touch the tension in the air. I said quietly to Hansen:

  ‘Nobody seems very happy. There’s still a hundred feet to go.’

  ‘There’s forty feet,’ Hansen said shortly. ‘Readings are taken from keel level and there’s sixty feet between the keel and the top of the sail. Forty feet minus the thickness of the ice — and maybe a razor-sharp or needle-pointed stalactite sticking down ready to skewer the Dolphin through the middle. You know what that means?’

  ‘That it’s time I started getting worried too?’

  Hansen smiled, but he wasn’t feeling like smiling. Neither was I, not any more.

  ‘Ninety feet,’ the diving officer said.

  ‘Thin ice, thin ice,’ Sanders intoned.

  ‘Switch off the deck flood, leave the sail flood on,’ Swanson said. ‘And keep that camera moving. Sonar?’

  ‘All clear,’ the sonar operator reported. ‘All clear all round.’ A pause, then: ‘No, hold it, hold it! Contact dead astern!’

  ‘How close?’ Swanson asked quickly.

  ‘Too close to say. Very close.’

  ‘She’s jumping!’ the diving officer called out sharply. ‘80, 75.’ The Dolphin had hit a layer of colder water or extra salinity.

  ‘Heavy ice, heavy ice!’ Sanders called out urgently.

  ‘Flood emergency!’ Swanson ordered — and this time it was an order.

  I felt the sudden build-up of air pressure as the diving officer vented the negative tank and tons of sea-water poured into the emergency diving tank, but it was too late. With a shuddering jarring smash that sent us staggering the Dolphin crashed violently into the ice above, glass tinkled, lights went out and the submarine started falling like a stone.

  ‘Blow negative to the mark!’ the diving officer called. High pressure air came boiling into the negative tank — at our rate of falling we would have been flattened by the sea-pressure before the pumps could even have begun to cope with the huge extra ballast load we had taken aboard in seconds. Two hundred feet, two hundred and fifty and we were still falling. Nobody spoke, everybody just stood or sat in a frozen position staring at the diving stand. It required no gift for telepathy to know the thought in every mind. It was obvious that the Dolphin had been struck aft by some underwater pressure ridge at the same instant as the sail had hit the heavy ice above: if the Dolphin had been holed aft this descent wasn’t going to stop until the pressure of a million tons of water had crushed and flattened the hull and in a flicker of time snuffed out the life of every man inside it.

  ‘Three hundred feet,’ the diving officer called out. ‘Three fifty — and she’s slowing! She’s slowing.’

  The Dolphin was still falling, sluggishly passing the four-hundred-foot mark, when Rawlings appeared in the control room, tool-kit in one hand, a crate of assorted lamps in the other.

  ‘It’s unnatural,’ he said. He appeared to be addressing the shattered lamp above the plot which he had immediately begun to repair. ‘Contrary to the laws of nature, I’ve always maintained. Mankind was never meant to probe beneath the depths of the ocean. Mark my words, those new-fangled inventions will come to a bad end.’

  ‘So will you, if you don’t keep quiet,’ Commander Swanson said acidly. But there was no reprimand in his face, he appreciated as well as any of us the therapeutic breath of fresh air that Rawlings had brought into that tension-laden atmosphere. ‘Holding?’ he went on to the diving officer.

  The diving officer raised a finger and grinned. Swanson nodded, swung the coiled-spring microphone in front of him. ‘Captain here,’ he said calmly. ‘Sorry about that bump. Report damage at once.’

  A green light flashed in the panel of a box beside him. Swanson touched a switch and a loudspeaker in the deck-head crackled.

  ‘Manoeuvring room here.’ The manoeuvring room was in the after end of the upper level engine-room, towards the stern. ‘Hit was directly above us here.
We could do with a box of candles and some of the dials and gauges are out of kilter. But we still got a roof over our heads.’

  ‘Thank you, Lieutenant. You can cope?’

  ‘Sure we can.’

  Swanson pressed another switch. ‘Stern room?’

  ‘We still attached to the ship?’ a cautious voice inquired.

  ‘You’re still attached to the ship,’ Swanson assured him. ‘Anything to report?’

  ‘Only that there’s going to be an awful lot of dirty laundry by the time we get back to Scotland. The washing-machine’s had a kind of fit.’

  Swanson smiled and switched off. His face was untroubled, he must have had a special sweat-absorbing mechanism on his face, I felt I could have done with a bath towel. He said to Hansen: ‘That was bad luck. A combination of a current where a current had no right to be, a temperature inversion where a temperature inversion had no right to be, and a pressure ridge where we least expected it. Not to mention the damned opacity of the water. What’s required is a few circuits until we know this polynya like the backs of our hands, a small offset to allow for drift and a little precautionary flooding as we approach the ninety-foot mark.’

  ‘Yes, sir. That’s what’s required. Point is, what are we going to do?’

  ‘Just that. Take her up and try again.’

  I had my pride so I refrained from mopping my brow. They took her up and tried again. At 200 feet and for fifteen minutes Swanson juggled propellers and rudder till he had the outline of the frozen polynya above as accurately limned on the plot as he could ever expect to have it. Then he positioned the Dolphin just outside one of the boundary lines and gave an order for a slow ascent.

  ‘One twenty feet,’ the diving officer said. ‘One hundred ten.’

  ‘Heavy ice,’ Sanders intoned. ‘Still heavy ice.’

  Sluggishly the Dolphin continued to rise. Next time in the control room, I promised myself, I wouldn’t forget that bath towel. Swanson said: ‘If we’ve overestimated the speed of the drift, there’s going to be another bump I’m afraid.’ He turned to Rawlings who was still busily repairing lights. ‘If I were you, I’d suspend operations for the present. You may have to start all over again in a moment and we don’t carry all that number of spares aboard.’

  ‘One hundred feet,’ the diving officer said. He didn’t sound as unhappy as his face looked.

  ‘The water’s clearing,’ Hansen said suddenly. ‘Look.’

  The water had cleared, not dramatically so, but enough. We could see the top corner of the sail clearly outlined on the TV screen. And then, suddenly, we could see something else again, heavy ugly ridged ice not a dozen feet above the sail.

  Water flooding into the tanks. The diving officer didn’t have to be told what to do, we’d gone up like an express lift the first time we’d hit a different water layer and once like that was enough in the life of any submarine.

  ‘Ninety feet,’ he reported. ‘Still rising.’ More water flooded in, then the sound died away. ‘She’s holding. Just under ninety feet.’

  ‘Keep her there.’ Swanson stared at the TV screen. ‘We’re drifting clear and into the polynya — I hope.’

  ‘Me too,’ Hansen said. ‘There can’t be more than a couple of feet between the top of the sail and that damned ugly stuff.’

  ‘There isn’t much room,’ Swanson acknowledged. ‘Sanders?’

  ‘Just a moment, sir. The graph looks kinda funny — no, we’re clear.’ He couldn’t keep the excitement out of his voice. ‘Thin ice!’

  I looked at the screen. He was right. I could see the vertical edge of a wall of ice move slowly across the screen, exposing clear water above.

  ‘Gently, now, gently,’ Swanson said. ‘And keep the camera on the ice wall at the side, then straight up, turn about.’

  The pumps began to throb again. The ice wall, less than ten yards away, began to drift slowly down past us.

  ‘Eighty-five feet,’ the diving officer reported. ‘Eighty.’

  ‘No hurry,’ Swanson said. ‘We’re sheltered from that drift by now.’

  ‘Seventy-five feet.’ The pumps stopped, and water began to flood into the tanks. ‘Seventy.’ The Dolphin was almost stopped now, drifting upwards as gently as thistledown. The camera switched upwards, and we could see the top corner of the sail clearly outlined with a smooth ceiling of ice floating down to meet it. More water gurgled into the tanks, the top of the sail met the ice with a barely perceptible bump and the Dolphin came to rest.

  ‘Beautifully done,’ Swanson said warmly to the diving officer. ‘Let’s try to give that ice a nudge. Are we slewing?’

  ‘Bearing constant.’

  Swanson nodded. The pumps hummed, pouring out water, lightening ship, steadily increasing positive buoyancy. The ice stayed where it was. More time passed, more water pumped out, and still nothing happened. I said softly to Hansen: ‘Why doesn’t he blow the main ballast? You’d get a few hundred tons of positive buoyancy in next to no time and even if that ice is forty inches thick it couldn’t survive all that pressure at a concentrated point.’

  ‘Neither could the Dolphin,’ Hansen said grimly. ‘With a suddenly induced big positive buoyancy like that, once she broke through she’d go up like a cork from a champagne bottle. The pressure hull might take it, I don’t know, but sure as little apples the rudder would be squashed flat as a piece of tin. Do you want to spend what little’s left of your life travelling in steadily decreasing circles under the polar ice-cap?’

  I didn’t want to spend what little was left of my life travelling in steadily decreasing circles under the ice-cap so I kept quiet. I watched Swanson as he walked across to the diving stand and studied the banked dials in silence for some seconds. I was beginning to become a little apprehensive about what Swanson would do next: I was beginning to realise, and not slowly either, that he was a lad who didn’t give up very easily.

  ‘That’s enough of that lot,’ he said to the diving officer. ‘If we go through now with all this pressure behind us we’ll be airborne. This ice is even thicker than we thought. We’ve tried the long steady shove and it hasn’t worked. A sharp tap is obviously what is needed. Flood her down, but gently, to eighty feet or so, a good sharp whiff of air into the ballast tanks and we’ll give our well-known imitation of a bull at a gate.’

  Whoever had installed the 240-ton air-conditioning unit in the Dolphin should have been prosecuted, it just wasn’t working any more. The air was very hot and stuffy — what little there was of it, that was. I looked around cautiously and saw that everyone else appeared to be suffering from this same shortage of air, all except Swanson, who seemed to carry his own built-in oxygen cylinder around with him. I hoped Swanson was keeping in mind the fact that the Dolphin had cost 120 million dollars to build. Hansen’s narrowed eyes held a definite core of worry and even the usually imperturbable Rawlings was rubbing a bristly blue chin with a hand the size and shape of a shovel. In the deep silence after Swanson had finished speaking the scraping noise sounded unusually loud, then was lost in the noise of water flooding into the tanks.

  We stared at the screen. Water continued to pour into the tanks until we could see a gap appear between the top of the sail and the ice. The pumps started up, slowly, to control the speed of descent. On the screen, the cone of light thrown on to the underside of the ice by the flood-lamp grew fainter and larger as we dropped, then remained stationary, neither moving nor growing in size. We had stopped.

  ‘Now,’ said Swanson. ‘Before that current gets us again.’

  There came the hissing roar of compressed air under high pressure entering the ballast tanks. The Dolphin started to move sluggishly upwards while we watched the cone of light on the ice slowly narrow and brighten.

  ‘More air,’ Swanson said.

  We were rising faster now, closing the gap to the ice all too quickly for my liking. Fifteen feet, twelve feet, ten feet.

  ‘More air,’ Swanson said.

  I braced myself, one hand
on the plot, the other on an overhead grab bar. On the screen, the ice was rushing down to meet us. Suddenly the picture quivered and danced, the Dolphin shuddered, jarred and echoed hollowly along its length, more lights went out, the picture came back on the screen, the sail was still lodged below the ice, then the Dolphin trembled and lurched and the deck pressed against our feet like an ascending elevator. The sail on the TV vanished, nothing but opaque white taking its place. The diving officer, his voice high with strain that had not yet found relief, called out. ‘Forty feet, forty feet.’ We had broken through.

  ‘There you are now,’ Swanson said mildly. ‘All it needed was a little perseverance.’ I looked at the short plump figure, the round good-humoured face, and wondered for the hundredth time why the nerveless iron men of this world so very seldom look the part.

  I let my pride have a holiday. I took my handkerchief from my pocket, wiped my face and said to Swanson: ‘Does this sort of thing go on all the time?’

  ‘Fortunately, perhaps, no.’ He smiled. He turned to the diving officer. ‘We’ve got our foothold on this rock. Let’s make sure we have a good belay.’

  For a few seconds more compressed air was bled into the tanks, then the diving officer said: ‘No chance of her dropping down now, Captain.’

  ‘Up periscope.’

  Again the long gleaming silver tube hissed up from its well. Swanson didn’t even bother folding down the hinged handles. He peered briefly into the eyepiece, then straightened.

  ‘Down periscope.’

  ‘Pretty cold up top?’ Hansen asked.

  Swanson nodded. ‘Water on the lens must have frozen solid as soon as it hit that air. Can’t see a thing.’ He turned to the diving officer. ‘Steady at forty?’

  ‘Guaranteed. And all the buoyancy we’ll ever want.’

  ‘Fair enough.’ Swanson looked at the quartermaster who was shrugging his way into a heavy sheepskin coat. ‘A little fresh air, Ellis, don’t you think?’

  ‘Right away, sir.’ Ellis buttoned his coat and added: ‘Might take some time.’

  ‘I don’t think so,’ Swanson said. ‘You may find the bridge and hatchways jammed with broken ice but I doubt it. My guess is that that ice is so thick that it will have fractured into very large sections and fallen outside clear of the bridge.’