Read Online Scorpion in the Sea by P.T. Deutermann - Free Book Online Page B
Authors: P.T. Deutermann
Ads: Link
discriminating hearing, and genuinely loved his work.
So: this must be an older ship, thought the Captain. The newer American ships carried lower frequency sonars, which they rarely used in the active, pinging mode. The Russians said that the Americans were using exclusively passive sonar now, letting their sophisticated computers listen to the low frequency spectrum, to the inaudible sounds made by motor bearings and pump motors and transmitted as tiny vibrations through the hull into the dark sea, where they travelled for miles due to their relatively
long acoustic wave lengths. Most navies had also recognized the beaconing effect an active sonar created: the pinging could always be heard by the submarine at nearly twice the distance that the submarine could be detected by the active sonar. Active pinging indicated an older ship, probably with poor or even no passive capability. Twin screws meant a destroyer, not a frigate. A frigate would have been passive. An old destroyer also meant no accursed helicopters. Their luck might still be holding.
He forced himself to concentrate, to squeeze out the background noises of the sea. The frequency of the pinging was even, not rising or falling. No discernible doppler effect. So, they were in omnidirectional mode. Not cued. Just … looking. And not going silent periodically to listen on passive equipment. No matter, he thought. For a diesel boat on the battery, passive was a waste of time. Compared to their nuclear powered sisters, with their noisy high pressure pumps and whining steam turbines, the diesel-electric submarines were quieter than the ambient noise of the sea itself. The only time they made noise detectable by passive equipment was when they went fast submerged and the screws cavitated, or when they used their diesel engines to recharge their batteries. Then they had to either surface, or to stick up a special pipe called a snorkel pipe, to get air for the diesel engines. The Foxtrot class could stay submerged for up to ten days without recharging the huge battery banks stuffed under and aft of the control room, but if they did the batteries would be seriously depleted.
The requirement to snorkel every few days was one of the reasons he had picked this area to hide in. The Jacksonville naval fleet operating areas were filled with diesel powered fishing boats, pleasure boats, and transiting merchant shipping. A submarine’s diesel engine breathing on the snorkel at night would sound like any other marine diesel to a listening passive sonar. As long as the oceans were filled with small and medium sized marine diesel engines, it was perfect cover, unless one happened to broach in full view of a fishing boat. He felt like rousting out the morning’s watch officer and shooting him right now, while this
destroyer was up there, except that the enemy would probably hear it.
He pulled off the earphones and handed them back. It was time to think. Like any submariner, he wanted to put the scope up and take a look, but that would be madness now, at the beginning of a search. Perhaps later, say at 0300, when their pursuers would be tired and bored.
“The layer?”
“Sir, the layer is at 25 meters, with a secondary gradient at 80 meters.”
The Captain pondered. Good, two layers. The young Palestinian had again used his head, maneuvering the sub right beneath the second layer. The ocean tended to settle itself into horizontal thermal layers, especially near the surface, like a vast, liquid parfait. In the warm waters off northern Florida, the first layer was normally only 20 to 25 meters deep, containing water whose temperature hovered around 80 degrees. The next layer was much colder, and its thickness varied. The layers beneath the first two became progressively colder and denser. The boundaries between the layers acted like the boundary between air and water, refracting the probing sound beams of an active sonar, much like the image of a fish seen just beneath the
So: this must be an older ship, thought the Captain. The newer American ships carried lower frequency sonars, which they rarely used in the active, pinging mode. The Russians said that the Americans were using exclusively passive sonar now, letting their sophisticated computers listen to the low frequency spectrum, to the inaudible sounds made by motor bearings and pump motors and transmitted as tiny vibrations through the hull into the dark sea, where they travelled for miles due to their relatively
long acoustic wave lengths. Most navies had also recognized the beaconing effect an active sonar created: the pinging could always be heard by the submarine at nearly twice the distance that the submarine could be detected by the active sonar. Active pinging indicated an older ship, probably with poor or even no passive capability. Twin screws meant a destroyer, not a frigate. A frigate would have been passive. An old destroyer also meant no accursed helicopters. Their luck might still be holding.
He forced himself to concentrate, to squeeze out the background noises of the sea. The frequency of the pinging was even, not rising or falling. No discernible doppler effect. So, they were in omnidirectional mode. Not cued. Just … looking. And not going silent periodically to listen on passive equipment. No matter, he thought. For a diesel boat on the battery, passive was a waste of time. Compared to their nuclear powered sisters, with their noisy high pressure pumps and whining steam turbines, the diesel-electric submarines were quieter than the ambient noise of the sea itself. The only time they made noise detectable by passive equipment was when they went fast submerged and the screws cavitated, or when they used their diesel engines to recharge their batteries. Then they had to either surface, or to stick up a special pipe called a snorkel pipe, to get air for the diesel engines. The Foxtrot class could stay submerged for up to ten days without recharging the huge battery banks stuffed under and aft of the control room, but if they did the batteries would be seriously depleted.
The requirement to snorkel every few days was one of the reasons he had picked this area to hide in. The Jacksonville naval fleet operating areas were filled with diesel powered fishing boats, pleasure boats, and transiting merchant shipping. A submarine’s diesel engine breathing on the snorkel at night would sound like any other marine diesel to a listening passive sonar. As long as the oceans were filled with small and medium sized marine diesel engines, it was perfect cover, unless one happened to broach in full view of a fishing boat. He felt like rousting out the morning’s watch officer and shooting him right now, while this
destroyer was up there, except that the enemy would probably hear it.
He pulled off the earphones and handed them back. It was time to think. Like any submariner, he wanted to put the scope up and take a look, but that would be madness now, at the beginning of a search. Perhaps later, say at 0300, when their pursuers would be tired and bored.
“The layer?”
“Sir, the layer is at 25 meters, with a secondary gradient at 80 meters.”
The Captain pondered. Good, two layers. The young Palestinian had again used his head, maneuvering the sub right beneath the second layer. The ocean tended to settle itself into horizontal thermal layers, especially near the surface, like a vast, liquid parfait. In the warm waters off northern Florida, the first layer was normally only 20 to 25 meters deep, containing water whose temperature hovered around 80 degrees. The next layer was much colder, and its thickness varied. The layers beneath the first two became progressively colder and denser. The boundaries between the layers acted like the boundary between air and water, refracting the probing sound beams of an active sonar, much like the image of a fish seen just beneath the
Similar Books
