The Sum of All Fears.pdf - Delta Force

'Lost it, the curve in the towed array just ruined our reception.' Rykov's hands
went up in frustration.
'Then we must be patient,' Dubinin said. It wasn't much of a joke, but the sonar
crew loved him for it.
***
'The Orion just engaged the inbound, sir, just picked up an ultrasonic sonar,
very faint, bearing two-four-zero. It's one of ours, it's a Mark 50, sir.'
'That ought to take care of him,' Ricks observed. 'Thank God.'
***
'Passing through fifty meters, leveling out, ten degrees on the planes. Speed
thirty-one.'
'Countermeasures didn't work . . .' Rykov said. The towed array was
straightening out, and the torpedo was still back there.
'No propeller noises?'
'None . . . I should be able to hear them even at this speed.'
'Must be one of their new ones . . .'
'The Mark 50? It's supposed to be a very clever little fish.'
'We will see about that. Yevgeniy, remember the surface action?' Dubinin smiled.
The Starpom did a superb job of maintaining control, but the thirty-foot seas
guaranteed that the submarine would broach – break the surface – as the waves
and troughs swept overhead. The torpedo was a scant three hundred meters behind
when the Akula leveled out. The American Mark 50 anti-submarine torpedo was not
a smart weapon, but a 'brilliant' one. It had identified and ignored the
countermeasures Dubinin had ordered only minutes before, and, using a powerful
ultrasonic sonar, was now looking for the sub in order to conclude its mission.
But here physical laws intervened in favor of the Russians. It is widely
believed that sonar reflects off the metal hull of a ship, but this is not true.
Rather, sonar reflects off the air inside a submarine, or more precisely off the
border of water and air through which the sound energy cannot pass. The Mark 50
was programmed to identify these air-water boundaries as ships. As the torpedo
rocketed after its prey, it began to see immense ship-shapes stretching as far
as its sonar could reach. Those were waves. Though the weapon had been
programmed to ignore a flat surface and thus avoid a problem called 'surface
capture,' its designers had not addressed the problem of a heavy, rolling sea.
The Mark 50 selected the nearest such shape, raced towards it –
– and sprang into clear air like a leaping salmon. It crashed into the back of
the next wave, reacquired the same immense target shape –
– and leaped again. This time the torpedo hit at a slight angle. Dynamic forces
caused it to turn and race north inside the body of a wave, sensing huge ships
both left and right. It turned left, springing into the air yet again, but this
time it hit the next wave hard enough to detonate its contact fuse.
***
'That was close!' Rykov said.
'No, not close, perhaps a thousand meters, but probably more.' The captain
leaned into the control room. 'Slow to five knots, down to thirty meters.'
***
'We hit it?'