With Michigan on a good evasion course, Wilson’s attention shifted to putting a second torpedo in the water against their adversary, the surprisingly capable mother ship. Sonar’s next report, however, threw a wrench into that plan.
“Conn, Sonar. Loss of Master one.”
Michigan was traveling at maximum speed, and the rush of water past the submarine’s acoustic sensors blunted their detection range. Michigan’s crew no longer held Master one. That meant Wilson would be shooting in the dark to some extent, using their last estimated target solution. If the mother ship maneuvered, Wilson’s crew would have no way of knowing.
Ultimately, what mattered most was putting another torpedo into the water, something for the mother ship to worry about and hopefully distract it from further attacks. Wilson was about to order Firing Point Procedures when Sonar’s report demanded his full attention.
“Conn, Sonar. Up doppler on first torpedo!”
The first torpedo had turned toward Michigan.
“Conn, Sonar. Up doppler on second torpedo!”
The second torpedo had also turned toward them.
It appeared that the mother ship still held Michigan on its sensors and had calculated its new course, sending steer commands to both torpedoes. The weapons were now closing in from each side in a rapidly constricting choke hold.
Wilson realized they were in a serious predicament. Both torpedoes were closing fast, and he couldn’t outrun them. They were MK 48 heavyweight versions, carrying much more fuel than lightweight torpedoes. He also couldn’t turn away, as either a left or right maneuver would turn into the path of one of the torpedoes.
Sonar announced, “Torpedo to starboard is range-gating. Torpedo is homing!”
One of the mother ship’s torpedoes had detected Michigan and verified it was a valid target, increasing the frequency of its sonar pings. It was now refining its target solution, adjusting its course and increasing speed as it closed the remaining distance.
“Conn, Sonar. Second torpedo is range-gating!”
The second torpedo was also homing.
“Eject countermeasures!” Wilson ordered.
Lieutenant Resor ejected a torpedo decoy, which would hopefully distract both torpedoes, plus a broadband jammer, which would mask Michigan’s sonar signature as it sped away. White scalloped icons appeared on the Control Room displays.
Wilson watched the bearings to both torpedoes intently as they approached Michigan’s countermeasures. Both torpedoes blew past them without even circling for a sniff. These torpedoes clearly had the most advanced version of the MK 48 operational software, able to discern between the large submarines they were designed to sink and the small decoys that emulated them.
He glanced at the nautical chart. Thankfully, they were in relatively shallow water — above crush depth — so his crew could survive if Michigan was sunk, assuming a rescue submersible arrived in time. At the moment, it looked like that was the likeliest scenario.
“Conn, Sonar. Both torpedoes are at one thousand yards and closing!”
Things looked hopeless for Michigan, but Wilson decided to order Firing Point Procedures. If Michigan was going down, they’d take the mother ship with them. The next several reports, however, delayed his plan.
“Conn. Sonar. Torpedo to port has turned away.” A few seconds later, Sonar followed up. “Torpedo to starboard has turned away.”
As Wilson contemplated the unexpected reports, another announcement emanated from the speakers.
“Conn, Sonar. Both torpedoes have shut down.”
The behavior of the two torpedoes was puzzling. Both had gained contact on Michigan and were homing to detonation. Outrunning a torpedo was always a strategy, but it appeared they hadn’t run out of fuel; they had turned away for some reason, then shut down. Perhaps there was a bug in the mother ship’s artificial intelligence or in the software loaded into the torpedoes it carried. Either issue was quite fortuitous, and Michigan had benefited.
As Wilson pondered the unusual torpedo behavior and a plan to reengage the mother ship, the next Sonar report added to Wilson’s confusion.
“Conn, Sonar. Regain of Master one on the towed array, bearing three-four-five. Contact is closing.”
Wilson checked the speed display in the Control Room. Michigan was still traveling at maximum speed, and not only had the mother ship maintained contact, tracking Michigan’s movements, but it had closed the distance. Built from leftover Seawolf propulsion components, the mother ship clearly had Seawolf speed.
The mother ship hadn’t fired additional torpedoes, so Wilson wondered what it was up to. Why would it close on Michigan? Typically, in submarine fights, a goal was to remain as far away as possible while still maintaining contact, providing valuable distance — and time — to respond to counterfire, and also reduce the probability the target would alert upon torpedo launch.
Perhaps the mother ship wasn’t as smart as Wilson initially thought. Its bizarre behavior had presented an unexpected opportunity.
Wilson announced, “Firing Point Procedures, Master one, tube One.”
As Michigan’s crew prepared to launch another torpedo, Sonar made another perplexing report.
“Conn, Sonar. Receiving underwater comms from Master one.”
The mother ship was attempting to communicate acoustically with another vehicle nearby.
“Sonar, Conn. Report all contacts.”
“Conn, Sonar. Hold only Master one.”
Wilson checked the nearest combat control console display. The mother ship was still gaining ground, paralleling Michigan’s track, and there was no indication that one of its UUVs was in the area. Was it possible the mother ship was attempting to communicate with Michigan? Did it think Wilson’s submarine was one of its UUVs or perhaps another mother ship?
Wilson ordered, “Sonar, Conn. Put the underwater comms on speaker.”
The warbly sound of verbal underwater communications emanated from the Control Room speakers, but the words were unintelligible. Michigan was traveling too fast, and the flow noise past the submarine’s sensors was distorting the sound.
After another glance at one of the combat control console displays — the mother ship kept closing while matching Michigan’s course — Wilson verified that the mother ship hadn’t displayed additional aggressive behavior. Now that Wilson thought about it, he realized that the mother ship had fired only in self-defense. Perhaps its protocols were functioning properly and it would attack only if fired upon.
Wilson decided to take a gamble. “Helm, ahead two-thirds.”
He slowed his submarine so the acoustic communications could be understood.
As Michigan’s speed decayed, the words became clear.
“Ohio class submarine. Identify yourself and the reason for your attack.”
What also became clear was that the mother submarine was quite capable, identifying Michigan as an Ohio class submarine from the tonals it emitted into the water. However, it had asked two questions that Wilson would normally not be able to answer.
During underwater communications between U.S. submarines, the vessels used code names to prevent anyone in the area who might intercept the communications from identifying which U.S. submarines were nearby. Wilson figured the mother ship likely didn’t have the codebook loaded into its memory banks, so he decided to answer the first question in plain English. The second question, however, couldn’t be answered, at least not truthfully. Wilson couldn’t tell the mother ship that Michigan was bent on destroying it. Perhaps he could strike up a dialog with the mother ship’s artificial intelligence and see where it led.