Bower had taken the Omega Deep here to test her maneuverability in confined spaces with the cloaking device engaged. A rift in the rocky plates three miles wide appeared much smaller when you were threading a submarine of such immense length. Besides, this was the first time any of them had tried the new navigation system.
Traditional submarine navigation systems rely on inertial guidance that keeps track of the ship's motion from a fixed starting point by using gyroscopes, or through active sonar to map their surroundings using echolocation, like a bat. The Omega Deep was different. It was fitted with a series of digital video cameras providing real-time footage in a 360-degree arc in all directions around the vessel.
Inside the command center, this live-feed was projected onto a central dome, which allowed the crew inside to view their surroundings. In clear water, it appeared more like looking out a glass window.
At this depth, with limited ambient light, and poor visibility, the system used LIDAR – Light Detection and Ranging – as well as infrared night vision – the same sort of technology used by ground soldiers equipped with night vision goggles. Basically, a set of lights projected infrared light, so that even in pitch dark, the sensors could then detect their surroundings.
If needed, immensely high-powered LED lights were capable of illuminating the darkest abyss. Again, because most traditional submarines, particularly Navy submarines, don’t have any windows, producing light didn’t reveal their position to other predator submersibles.
Belinda Callaghan, one of his junior sonar technicians, said, “Sir, we have a contact approaching from 47 degrees north-northwest.”
Commander Bower felt a slight prickle in the hairs on the back of his neck. They were more than five hundred miles from any major land sources. “What have we got?”
“A submersible. Very small. No more than ten to fifteen feet in length. Shaped more like a miniature plane, flying underwater at a speed of twelve knots, sir.”
“Is it approaching from above the valley or within?”
“Within, sir.”
“Range?” Commander Bower asked.
“Three miles and closing,” she said.
“That’s close,” he observed, in a tone of displeasure. In the middle of a shipping lane, with hundreds of sounds, he could have forgiven her for not noticing it before now, but where they were, the high-pitched whine of the submersible’s twin engines should have been spotted immediately. “Where’s its surface ship?”
“There isn’t one, sir.”
“Impossible.” Bower glanced at the sonar operator’s monitor. “A small submersible like that needs a mothership out here. There’s no way it would have the range to make the journey by itself. Locate the mothership.”
Callaghan stood her ground. “There isn’t one, sir. The closest ship is the Antarctic Solace – and she’s nearly 200 miles away.”
That jolted Bower. “All right. If there’s no ship nearby, the mini-sub is attached to something. That means there’s another submarine prowling around here.”
“I’m on it, sir,” she confirmed, adjusting her sonar monitoring to target the small telltale signs of a large submarine running silent.
“Pilot, bring us to a full stop,” Bower commanded. “No reason to risk someone picking up our wake.”
The XO’s deep-set eyes were hooded with concern. “Should we decrease our depth and put some more room beneath our keel just to be on the safe side?”
Bower turned to Callaghan. “What depth are you tracking the submersible at?”
She replied without hesitation. “Four hundred feet, sir.”
Bower nodded. “All right Mr. Halifax. That’s a hundred feet to spare. I’m happy to stay at this depth and let the sub pass beneath our keel.” Meeting his XO’s eyes, and valuing the man’s input, he asked, “What do you think?”
“Agreed, sir. Let’s sit it out and see what she does.”
“Very good.” Bower turned to the pilot and copilot. “Pilot, maintain all, stop.”
“Maintaining all, stop, sir.”
All eyes within the command center watched the large digital monitor, which displayed a synchronized image of the sonar screen. It counted down the distance of the approaching submersible. At first, it registered miles.
As it came closer, it recorded feet.
Despite the hull’s soundproofing, the crew became naturally silent.
Commander Bower smiled. “It’s all right, everyone. The Omega Deep was built for this. There’s no reason to remain silent. Nothing you can say inside the hull will be picked up outside.” Then, as if to prove a point, he shouted, “Woohoo!”
The sound echoed throughout the submarine.
No one followed suit.
And soon the command center was completely silent once more, the shallow breaths of the men and women who served were the only sounds that remained.
A slow smile curled Bower’s lips. Once a submariner, always a submariner. The need to run silent was etched deep in every submariner’s psyche.
Callaghan broke the silence. “Sir, it should be in visual range any second now.”
“Thank you,” he acknowledged.
Bower turned his gaze toward the downward-facing dome beneath the Perspex flooring. Like the one above his head which showed the area above, this one showed a 360-degree half-sphere vision of the area below the keel.
Twin bright lights appeared in the speckled darkness below.
At that distance, it could have been nothing more than a strange sea-creature of the deep, like an anglerfish – the type that holds a light above their head? – but as the range diminished, the lights increased, revealing the slightest shape of an underwater vehicle.
Commander Bower said, “Lieutenant Callaghan, can you please play any external sound received by the hydrophone on the overhead speakers.”
Callaghan adjusted her control and removed her headset. “Yes, sir.”
The gentle electric whine of twin thrusters filled the command center. Bower stared at the light. From a hundred feet, it was impossible to make out the shape of the submersible, but he recognized the whine of the electric motors – although he didn’t quite believe his ears.
Bower turned to his left. “Navigation, can you please get me a visual of that sub using LIDAR?”
“Yes, sir.”
A moment later, a clear image of the submersible came up on one of the overhead display screens. The submersible’s exact dimensions were: 20 feet of length, beam 14 feet – with a 7-foot wingspan – and a height of 5 feet. There were two glass bubble domes positioned forward and aft of each other, where a single pilot and copilot were housed. The overall shape of the submersible was sleek, like a sports-car, or more accurately, a sports underwater airplane, with narrow wings and a V-shaped tail-wing. The wings even had two large thrusters fixed, one to each wing, like jet-engines on an aircraft.
It was the sort of toy a billionaire would purchase.
Commander Bower breathed out, consciously feeling any tension that had developed slip away. A broad grin pierced his otherwise stern face. “My goodness, what the hell is a lone Orcasub doing all the way out here?”
The XO asked, “An Orcasub, sir?”
Commander Bower nodded. “It’s basically what it looks like. A two-person, flying submersible. It’s built by Nuytco Research – the same people who build our atmospheric dive suits. Look at that thing. It’s the ultimate luxury item for a billionaire. They are small enough to be easily lifted off the deck of a pleasure yacht.”
The XO’s eyebrows narrowed. “Which begs the question, where’s the pleasure yacht?”
Bower turned to face his junior sonar operator. “Lieutenant Callaghan, any sign of another submarine or a ship?”
“Nothing.”
Commander Bower turned to his XO and shrugged. “How about we follow it and find out?”
“Yes, sir,” The XO replied expressionlessly.
The CO was not known for reckless or fickle behavior. It was
for this very reason that the XO was surprised to receive the order to pursue the unidentified submersible. It appeared that the old man’s curiosity had finally gotten the better of him.
No one aboard the Omega Deep could have guessed that they might end up paying for his decision with their lives.
*
The promotion had thrilled Belinda Callaghan, Sonar Technician, Second Class. With it, came a position on the highly secret, experimental, Virginia class block VII nuclear attack submarine, Omega Deep.
Everything about her experience on board the Omega Deep had exceeded her expectations. She sat at her console, manning the large-aperture, bow-mounted sonar array. A state-of-the-art set of devices, it could glean the faintest of sonar impressions from the ocean near and far.
This was her second posting, but the first assignment to a new asset. Her exceptional results at submarine “A” School in Groton, Connecticut, had seen her fast-tracked on board the North Carolina when natural attrition yielded an STS – Sonar Technician Submarine.
During that tenure, she detected and correctly identified a Chinese Type 094 submarine in the South China Sea at a distance of 18,000 feet. She earned herself a founding position on the Omega Deep right then and there. Captain Bower took careful note of her talents, and when the time came, he chose her.
She knew that sonar was an art. A good sonar technician must be dedicated to that art. They must think, dream and live sonar all day, every day while on board. Listening to that feed and reading the screen takes a nuanced approach because it’s the subtleties that make the sonar image.
Callaghan’s exceptional attention to detail and her methodical approach made her successful, and her dedication to continuous training made her competitive to a point. Her fellow techs knew they would one day be under her command – she could out-chart, and out-plot any of them with the roughest of data. She wanted to be the Navy’s first female Sonar Chief, and anybody that worked alongside her figured out pretty quickly she had the tenacity to get there.
All she needed was the chance to prove herself.
Right now, she’d been given that chance.
The CO had asked her, specifically, to search for the Orcasub’s mothership or submarine, and she was determined to find it.
Belinda Callaghan made a digital recording of the Orcasub’s soundwave. Like fingerprints, these could be used to identify an individual ship or submarine from any others in the water. She adjusted the computer system settings to remove all sounds associated with that submersible. In doing so, it allowed her to concentrate on her search for a second vessel.
Belinda felt the Omega Deep change direction, as her CO ordered the pilots to set a course to follow the strange yellow Orcasub. She placed slightly more pressure on her right foot, as a means of stabilizing herself. Mentally, she detached herself from the submarine’s movement and from attempting to gain a visual. Instead, she focused on her sonar screen, and let her ears search for any abnormal sounds hidden within the noise of the deep, which constantly bombarded her headphones.
It was a little over thirty minutes before she heard it.
The anomaly started out like a tiny smudge on her screen, and the sound she heard was unlike any other she could place. Her entire body went rigid like stone as she adjusted the volume on the feed and scoured the image for another trace of it.
There it was again!
She allowed herself a thin-lipped smile.
Tiny, infinitesimal – but definitely there. The image reflected a skinny worm for a fleeting moment, and then it was gone.
Was it man-made or natural?
Belinda closed her eyes and listened. She made the conscious effort to control her breathing and slow her heart rate. With everything amplified in her headphones, it was easy to end up listening to the sound of her breaths, and her heart beat instead of what was out there.
She opened her eyes and frowned. Because what was out there, had stopped. Scrolling back to her original recording of the sound’s waveform, she replayed the alien sound.
What were you?
When you first start out as a sonar technician and put the hydrophone headphones on, all you hear is a discombobulated world of more than a thousand marine sounds, both artificial and natural. But as you progress through your training, it becomes easy to differentiate between the artificial sounds of a submarine or the natural sounds of marine-life. Soon, you can train your ears to differentiate between individual marine life sounds and artificial sounds. After more than three thousand hours at the sonar station, it was unusual to find anything completely alien to her ears.
She shook her head. Frustrated, she continued to search for the strange sound and the second submarine.
Then she heard the alien sound again.
She smiled.
You’ve come back, have you?
This time she was certain it was artificial.
It was man-made, it must have been. No animal sounds like that. She dithered.
Is it man-made?
Do I interrupt the commander, yet?
She waited. Silent as stone and motionless. She checked the log, four minutes passed, and still, she waited. Nothing. She cursed herself. She tried to breathe silently and strained to listen over the sound of the blood slamming in her eardrums. She slowed her breathing, in a technique she’d picked up in yoga as a means of slowing her heart rate, reducing her blood pressure, and being more in the present.
Then there it was. Unmistakable. Louder this time.
She turned to the tech next to her just as he said it. “Did you get that?”
“What is that?” she asked, excited now.
“I’ve no idea,” he replied. “but we’d better tell the Chief.”
“I’ll start plotting it,” Belinda said, hopeful of an opportunity to prove herself again.
Callaghan squelched the controls on her sonar station to hone in on the heading given by the mysterious sound. The monitor she primarily used was a computer-generated visual representation of the soundtrack on the feed from the sensors. It produced a three-dimensional representation similar to modern radar.
Alternatively, she could switch to an old-fashioned waterfall type screen, which graphed a horizontal measure of bearing, against a vertical increment of frequency. It was this type of device that she had trained on originally, and it was this one she fell back on when exploring the murky depths that the computer algorithms couldn’t diagnose.
The signal she searched was shallow. Very shallow. Which made it harder to detect and distinguish between the other sounds.
To a sonar technician, depth is a friend. The deeper the signal, the less likely it is to be polluted by interference caused by sea life or debris. If you’re lucky, the sound might travel through a deep sound channel – the perfect conditions for sound propagation.
In this case, the sound was in shallow water. Possibly even a hundred feet. The sound image was difficult to make out because the wavelength was being bounced around through the underwater valley through which they were currently traveling.
She let her eyes drift along in time with the leading edge of the waterfall display. She pushed the gain all the way to the maximum. Static and mechanical noise from the ship built a cacophony of baseline noise in her headphones. Winding it back just a touch, she found the noise again – this time with a heading, and with a matching slug shape on the waterfall readout. A rush of adrenaline gushed from her kidneys straight down her spine – shooting into her gut like white-hot fire.
Oh my God! It’s a submarine!
She hit the print detail button and continued scrambling her gear to get a precise reading. As it printed, the Chief Sonar operator reached over and tore off the glossy paper from beside her. With an encouraging pat on the shoulder, he indicated he was taking it to the commander, who was as yet unaware of the situation.
The heading was 225 degrees southwest, at a distance of approximately 7,000 feet. It was coming together for her. She was on this thing.
> She took a deep breath to steady herself.
Focus.
Whose is it?
She immediately knew what she was listening to. She set the audio scanner to 60 Hz and listened, waiting. A vessel runs its electronics on alternating current at a set frequency, measured in Hertz. If the electronics on that ship become waterlogged, are improperly mounted against the hull, or damaged they emit the sound of that particular operating current into the ocean.
Ships the world over use a standardized current for their electronics – 50 Hz. There was, however, one nation that used a different current for their entire fleet of submarines run on a 60 Hz system.
The United States.
Belinda’s heart sank. She was looking at a stricken United States submarine. Stranded deep in the ocean and most probably damaged. Her throat tightened, and the moisture evaporated from her mouth. She stared at the worm which was now perfectly focused on her monitor.
*
Commander Bower stared at the two enlarged images of the Orcasub pilot and copilot. Their faces were distorted by the glass dome, but he hoped someone from one of the digital intelligence teams, back stateside, might be able to improve the image and then identify them.
He put the two images back down next to the navigation table and turned his focus to the downward-facing digital dome.
His eyes swept the surreal environment beneath the Omega Deep, taking in the deep trench, sharp and vertical edges of the sea valley, and finally fixing on the glowing light of the Orcasub. It was moving at a spritely twelve knots – its two occupants, apparently unaware of the massive submarine’s overhead pursuit.
Behind the visual dome, the Omega Deep’s pilot and copilot maintained a course just fifty feet behind and twenty feet above the Orcasub. The water was crystal clear, and the light from the Orcasub was plentiful enough to navigate by.
They followed the Orcasub, matching it as it banked to the right and rose to a hundred and fifty feet in order to enter a smaller tributary valley.
The pilot said, “Requesting approval to follow, sir?”
To the navigation officer, Bower asked, “Does LIDAR mapping confirm there’s enough room to pursue?”
Omega Deep (Sam Reilly Book 12) Page 3
