“Commander Mackenzie, welcome aboard the USS Billfish.”
This greeting came from a wiry, khaki-clad officer who stood at Mac’s side. He continued, “I’m Lieutenant Commander Jenkins, the sub’s XO. Captain Holden is up in the sail and sends his respects. I’m afraid that time is a bit critical, so if it’s all right with you, we’d like to get you loaded into the DSRV and get on with the dive.”
“Lead on, Mr. Jenkins,” replied Mac, who was relieved that his long journey was finally about to end.
As they proceeded around the sail, Mac noted that the chopping roar of the helicopter was no longer audible.
This racket was replaced by the splashing sound of lapping water as it gently broke against the sub’s rounded hull. The warm night air was fresh and smelled of the sea. Quite happy to be back in this familiar medium, Mac traversed the vessel’s spine, finally coming to a halt beside the DSRV. Here he spotted an individual dressed in dark blue coveralls, in the process of inspecting the mini-sub’s forward thruster ducts. It proved to be the XO, who provided the introductions.
“Commander Mackenzie, I’d like you to meet the DSRV Avalon’s pilot, Lieutenant Richard Sullivan.”
Mac accepted the pilot’s cool handshake. The lieutenant was well into his forties and displayed a lined, weather-worn face as he looked Mac directly in the eyes.
“The Avalon’s ready to go whenever you are, Commander.”
Mac sized him up as a man who had worked his way up through the ranks. He exuded confidence, and Mac felt instantly at ease with him.
“Were you the one who made the initial discovery?” asked Mac.
“I’m the one,” the pilot answered.
“I’d be happy to give you a complete briefing once we get underway.”
“I’d like that, returned Mac. He followed Sullivan as he climbed a portable ladder that was propped against the DSRV’s side.
A humped casing on the Avalon’s upper deck hid a narrow hatchway. As Lieutenant Sullivan opened the hatch, the XO of the USS Billfish called out to Mac.
“Have a safe voyage, Commander. If you need anything, just ring us up on the underwater telephone.”
Mac returned his salute and then followed the Avalon’s pilot down into the DSRV’s interior. A short climb led to the main pressure capsule. The air was cool here and smelled of machine oil. By the light of a red lamp they moved forward. This put them in the central command module. While the pilot settled into the padded chair on the port side, Mac squeezed into the seat beside it. Following the grizzled veteran’s example, Mac fastened his safety harness.
“I take it you’re no stranger to a deep submergence rescue vehicle, Commander.”
“Actually, I spent some time on the Mystic. And please, call me Mac.”
The pilot continued while addressing the various switches and buttons of his console.
“You wouldn’t happen to know Matt Crowley, would you?”
“I certainly would,” answered Mac.
“Matt was my driver during a dive off Kauai.”
“Good op angles-and-dangles Crowley,” reflected the pilot.
“He taught me the business, and was almost responsible for getting me to muster out of the service early. That guy’s scared of nothing.”
Mac grinned.
“So I’ve noticed.”
The intercom activated, and they were informed that the Billfish was standing by to dive. Only when he was absolutely certain that the Avalon was properly pressurized did the pilot notify their mother ship that they were also ready for the black depths below. A raucous blast of compressed air signaled that the dive was on. Still anchored piggyback-style on the deck of the Billfish, the DSRV slid beneath the surface of the sea.
“How long until we disengage?” asked Mac.
“A couple of minutes at most.”
“Does that give us time for that briefing you promised me?”
The pilot nodded.
“The Avalon was in Sydney when I received my current orders. The Aussie Navy is thinking about building a couple of DSRVs of their own, and they’d like to use Avalon as a prototype. Since I was ordered up here ASAP, MATS sent in a C5-A that subsequently carried Avalon to the airstrip at Kwajalein.
From here we were mounted on the back of the Billfish.
“The Avalon’s primary mission was to search the waters surrounding the atoll for any recently deposited debris.
It seems that the Air Force lost some sort of warhead in the area after a successful test launch from Vandenberg, and it was hoped that we would be the ones to sniff it out for them.
“After scouring the lagoon and finding not a trace of the warhead, we expanded the search to the surrounding ocean. It was while examining the waters directly south of the lagoon’s entrance that our bottom scanning sonar registered a minor irregularity on the seafloor, at a depth of six-hundred and seventy-eight feet. I decided to bring the Avalon down to eyeball this anomaly, and that’s when I made the initial discovery.”
A soft electronic tone began sounding in the background, and the pilot excused himself to begin the disengagement process. He utilized the underwater telephone to coordinate this process with the USS Billfish, and soon afterward the Avalon was free from its mother vessel and totally on its own.
With the assistance of an airplane-type steering column, the pilot guided the DSRV downward. At a depth of five hundred feet he hit a clear plastic button on the sonar console. Almost immediately a repetitious, soft warbling ping began sounding from the elevated intercom speakers.
“That sound that you’re hearing is from a set of homing beacons we placed at the site. It will lead us straight to the area in question.”
Mac sat forward excitedly. His pulse quickened as they passed below six hundred feet and the pilot activated the Avalon’s powerful bow-mounted spotlights and its video camera. Now all Mac had to do was gaze up at the monitor screen to see for himself what secrets the ocean had in store for them.
A startled grouper darted into the blackness beyond, while a curious gray shark stared into the camera as if it was considering it as a possible food source. After adjusting the monitor’s fine-tuning knob, the pilot continued.
“I don’t really know what I was expecting to find down here. But I’ll tell you this much, in my ten years of work on DSRVs, I haven’t ever seen anything like what you’re about to see with your very own eyes. Why, it just doesn’t make any rational sense!”
Mac’s mouth was bone dry as they dropped below six hundred and fifty feet. On the monitor screen, the gray shark was no longer visible. In its place was a faint blue beacon whose strobe seemed to be synchronized with the pinging tone that was still emanating from the Avalon’s intercom.
“That’s the homing beacon,” observed the pilot.
“The site is only a few meters from its base.”
It seemed to take forever for the DSRV to cover this distance. As they passed the strobe, the pilot took manual control of the video camera and aimed its lens straight at the seafloor.
An expanse of smooth golden sand filled the monitor screen. Yet as they sped over a nesting starfish, the character of the sand abruptly changed. Its previously glossy surface was now pockmarked by a set of alien tracks. This trail seemed manmade, the individual treads appearing much like that which would be left in the wake of some sort of subterranean tractor.
Mac noted the shape of the tread marks and the width of the track itself. Though he would need to take exact measurements, there was no doubt in his mind that Admiral Long’s suspicions had been correct.
Only three weeks ago, Mac had seen an exact duplicate of this same track on the seafloor beneath San Francisco harbor. The previous month, he had examined another similar trail off the coast of Norfolk, Virginia, in Chesapeake Bay. Earlier in the year, other tracks were found in the Mediterranean Sea near Sicily, and on the seafloor of the Baltic opposite the Swedish city of Karlskrona. Each of these sightings pointed to the presence of some sort of mysterious vessel that used a tracked drive to prowl the seafloor. What made this supposition all the more chilling was the fact that each of these sightings occurred in the restricted waters adjoining a variety of the West’s most sensitive military installations.