CHAPTER THIRTY-ONE – Terminal Velocity
Commander Norton had never yet lost a man, and he had no intention of starting now. Even before Jimmy had set off for the South Pole, he had been considering ways of rescuing him in the event of accident; the problem, however, had turned out to be so difficult that he had found no answer. All that he had managed to do was to eliminate every obvious solution.
How does one climb a half-kilometre vertical cliff; even in reduced gravity? With the right equipment – and training – it would be easy enough. But there were no piton-guns aboard Endeavour, and no one could think of any other practical way of driving the necessary hundreds of spikes into that hard, mirror surface.
He had glanced briefly at more exotic solutions, some frankly crazy. Perhaps a simp, fitted with suction pads, could make the ascent. But even if this scheme was practical, how long would it take to manufacture and test such equipment – and to train a simp to use it? He doubted if a man would have the necessary strength to perform the feat.
Then there was more advanced technology. The EVA propulsion units were tempting, but their thrust was too small, since they were designed for zero-gee operation. They could not possibly lift the weight of a man, even against Rama’s modest gravity.
Could an EVA thrust be sent up on automatic control, carrying only a rescue line? He had tried out this idea on Sergeant Myron, who had promptly shot it down in flames. There were, the engineer pointed out, severe stability problems; they might be solved, but it would take a long time – much longer than they could afford.
What about balloons? There seemed a faint possibility here, if they could devise an envelope and a sufficiently compact source of heat. This was the only approach that Norton had not dismissed, when the problem suddenly ceased to be one of theory, and became a matter of life and death, dominating the news in all the inhabited worlds.
While Jimmy was making his trek along the edge of the Sea, half the crackpots in the solar system were trying to save him. At Fleet Headquarters, all the suggestions were considered, and about one in a thousand was forwarded to Endeavour. Dr Carlisle Perera’ arrived twice – once via the Survey’s own network, and once by PLANETCOM, RAMA PRIORITY. It had taken the scientist approximately five minutes of thought and one millisecond of computer time.
At first, Commander Norton thought it was a joke in very poor taste. Then he saw the sender’s name and the attached calculations, and did a quick double-take.
He handed the message to Karl Mercer.
‘What do you think of this?’ he asked, in as non-com- mittal a tone of voice as he could manage.
Karl read it swiftly, then said, ‘Well I’m damned! He’s right, of course.’
‘Are you sure?’
‘He was right about the storm, wasn’t he? We should have thought of this; it makes me feel a fool.’
‘You have company. The next problem is – how do we break it to Jimmy?’
‘I don’t think we should … until the last possible min-ute. That’s how I’d prefer it, if I was in his place. Just tell him we’re on the way.’ Though he could look across the full width of the Cylindrical Sea, and knew the general direction from which Resolution was coming, Jimmy did not spot the tiny craft until it had already passed New York. It seemed incredible that it could carry six men – and whatever equipment they had brought to rescue him.
When it was only a kilometre away, he recognized Commander Norton, and started waving. A little later the skipper spotted him, and waved back.
‘Glad to see you’re in good shape, Jimmy,’ he radioed. ‘I promised we wouldn’t leave you behind. Now do you believe me?’
Not quite, Jimmy thought; until this moment he had still wondered if this was all a kindly plot to keep up his morale. But the Commander would not have crossed the Sea just to say goodbye; he must have worked out something. ‘I’ll believe you, Skipper,’ he said, ‘when I’m down there on the deck. Now will you tell me how I’m going to make it?’
Resolution was now slowing down, a hundred metres from the base of the cliff; as far as Jimmy could tell, she carried no unusual equipment – though he was not sure what he had expected to see.
‘Sorry about that, Jimmy – but we didn’t want you to have too many things to worry about.’
Now that sounded ominous; what the devil did he mean?
Resolution came to a halt, fifty metres out and five hundred below; Jimmy had almost a bird’s-eye view of the Commander as he spoke into his microphone.
‘This is it, Jimmy. You’ll be perfectly safe, but it will require nerve. We know you’ve got plenty of that. You’re going to jump.’
‘Five hundred metres!’
‘Yes, but at only half a gee.’
‘So – have you ever fallen two hundred and fifty on Earth?’
‘Shut up, or I’ll cancel your next leave. You should have worked this out for yourself… it’s just a question of terminal velocity. In this atmosphere, you can’t reach more than ninety kilometres an hour – whether you fall two hundred or two thousand metres. Ninety’s a little high for comfort, but we can trim it some more. This is what you’ll have to do, so listen carefully…’
‘I will,’ said Jimmy. ‘It had better be good.’
He did not interrupt the Commander again, and made no comment when Norton had finished. Yes, it made sense, and was so absurdly simple that it would take a genius to think of it. And, perhaps, someone who did not expect to do it himself…
Jimmy had never tried high-diving, or made a delayed parachute drop, which would have given him some psychological preparation for this feat. One could tell a man that it was perfectly safe to walk a plank across an abyss – yet even if the structural calculations were impeccable, he might still be unable to do it. Now Jimmy understood why the Commander had been so evasive about the details of the rescue. He had been given no time to brood, or to think of objections.
‘I don’t want to hurry you,’ said Norton’s persuasive voice from half a kilometre below. ‘But the sooner the better.’ Jimmy looked at his precious souvenir, the only flower in Rama. He wrapped it very carefully in his grimy handkerchief, knotted the fabric, and tossed it over the edge of the cliff.
It fluttered down with reassuring slowness, but it also took a very long time getting smaller, and smaller, and smaller, until he could no longer see it. But then Resolution surged forward, and he knew that it had been spotted.
‘Beautiful!’ exclaimed the Commander enthusiastic-ally. ‘I’m sure they’ll name it after’ you. OK – we’re waiting…
Jimmy stripped off his shirt – the only upper garment anyone ever wore in this now tropical climate – and stretched it thoughtfully. Several times on his trek he life.
For the last time, he looked back at the hollow world he alone had explored, and the distant, ominous pin-nacles of the Big and Little Horns. Then, grasping the shirt firmly with his right hand, he took a running jump as far out over the cliff as he could. Now there was no particular hurry; he had a full twenty seconds in which to enjoy the experience. But he did not waste any time, as the wind strengthened around him and Resolution slowly expanded in his field of view. Holding his shirt with both hands, he stretched his arms above his. head, so that the rushing air filled the garment and blew it into a hollow tube.
As a parachute, it was hardly a success; the few kilometres an hour it subtracted from his speed was useful, but not vital. It was doing a much more important job – keeping his body vertical, so that he would arrow straight into the sea.
He still had the impression that he was not moving at all, but that the water below was rushing up towards him. Once he had committed himself, he had no sense of fear; indeed, he felt a certain indignation against the skipper for keeping him in the dark. Did he really think that he would be scared to jump, if he had to brood over it too long?
At the very last moment, he let go of his shirt, took a deep breath, and grabbed his mouth and nose with his hands. As he had been instructed, he stiffened his body into a rigid bar, and locked his feet together. He would enter the water as cleanly as a falling spear…
‘It will be just the same,’ the Commander had promised, ‘as stepping off a diving board on Earth. Nothing to it – if you make a good entry.’