On March 26, 1945, however, Operation PX had been cancelled on the orders of General Yoshijiro Umezu, Chief of the Army General Staff. "Germ warfare against the United States," Umezu had declared, "will escalate into war against all humanity."
And so the IJN's planning staff had shifted their sights to another possibility — a sneak air attack against the Panama Canal. If the Gatun Locks could be destroyed, Gatun Lake would be emptied, blocking the canal for months and seriously delaying the redeployment of elements of the U.S. Atlantic Fleet to the Pacific, where they would be employed in the inevitable invasion of the Japanese home islands.
Hawking added a bit of forward throttle and gained altitude, skimming past the conning tower and banking to port in front of the forward end of her 115-foot hangar. He could see something fallen on deck along the port side forward… probably the boat's enormous hydraulic crane… or possibly it had been lowered and stored that way. The I-401 had an eighty-five-foot pneumatic catapult extending from the hangar door to the bow. Reportedly, the submarine aircraft carrier could surface and all three torpedo bombers could be assembled, armed, fueled, and launched within forty-five minutes. Those floatplanes could land alongside after their mission was complete and be hauled aboard by that crane; likely, though, their raid against the Panama Canal would have been a one-way flight. Kamikaze.
But, of course, the raid against the canal had never come off. During the summer months of 1945, some three thousand ships of the United States Navy began closing in on the Japanese home islands in preparation for Operation Olympic, the invasion of Japan. The Panama Canal raid had been cancelled, and the four submarines of SubRon One were redeployed for an operation closer to home — Operation Arashi, or "Mountain Storm." I-13 was sunk en route, but the remaining three rendezvoused at the embattled Japanese base at Truk and prepared for a raid against the U.S. fleet at Ulithi, scheduled for August 17. The eight Aichi aircraft were painted with fake American markings, to let them get in close.
History caught up with the I-401, however, when the atomic bombs were dropped on Hiroshima and Nagasaki, and, on August 15, the Emperor broadcast his order to surrender. By the end of August, the I-401 and her consorts were under American command.
Under skeleton American and Japanese crews, all three had been conned across the Pacific to Hawaii, where they'd arrived in January 1946 to a spectacular welcoming celebration. In March, however, it was decided to dispose of the captured supersubs… reportedly because the Russians were demanding access to them. I-401 had been scuttled, sent to the bottom here off Kalaeloa Harbor, and here she had rested for over six decades, until the slowly corroding hulk had been discovered by accident by a deep-sea research team in 2005. On subsequent dives, they'd attached the sonar locator transponder, and several research teams had visited her since in deep submersibles or with robotic underwater vehicles.
Hawking completed his circuit of the I-401's upper works, noting how the conning tower was offset some seven feet to port off the centerline, while the long hangar was offset two feet to starboard to compensate. That monster, he decided, must have been a bitch to maneuver, with a sharper turning radius to starboard than to port.
The I-401 was decades ahead of her time, anticipating, in some ways, the Ohio-class conversion and the use of on-board submersible fighters like the Manta. Ohio's new mission, as he understood it, was similar in many respects to that of the I-401—to take the war to the enemy's coast.
A series of sharp chirps sounded from his console — a message alert. Radio didn't work across more than a few meters of water, and the various new phone systems using sound transmitted through the water were still unreliable at great depth. The chirping signal was unambiguous, however. Surface at once.
Pity. He'd hoped to make several circuits of the sunken behemoth, but if he didn't take the Manta to the surface at once, he could expect a real ass-chewing from Captain Hargreave and the submersible test bed facility brass at Pearl Harbor. Maneuvering well clear of the I-401, he took a last look at her vast and shadowed bulk receding into the night once more, then cut in full power to the Manta's thrusters and pulled back on the yoke. Nosing high, he began to angle up toward daylight, just over half a mile overhead.
Piloting the Manta, he reflected, involved one important difference from traditional flight. With an airplane, as his flight instructor at Pensacola had always said, "Whether or not you take off is optional; landing is mandatory." In other words, if you got off the ground, you would be coming back down again, one way or another.
With the Manta, though, it was just the opposite.
Negative buoyancy meant that the fighter sub was guaranteed to sink when it entered the water; getting back to the surface at the end of the mission was the worrisome part. If the engine or power plant gave out on him, the Manta would nose over and begin a one-way descent to the bottom once more… and he would get to test the ejection/surface escape system. That system, he was all too aware, had never been tested in an operational XSSF-1; there were only two test bed models available, and they were too damned expensive to lose in a test of the ejector system.
Minutes passed, however, and all of his readouts stayed green. He kept a particularly sharp eye on the hull stress sensors; as the outside pressure was relieved, the hull tended to flex and expand slightly—"unpacking" was what the engineers called it. If there was going to be a problem, this would be the time.
But as more minutes passed and the waters above began to show a faint tinge of luminous blue, it became clear that, once again, the Manta had passed her quals with flying colors. At thirty meters he could see the surface as a dancing pattern of blue and green. At ten meters he could see the hull of the Dolores Chouest, his mother ship, off to starboard.
Moments later he brought the sub level and rode the canopy through the surface, breaching in a burst of white spray, and he felt the craft's heavy roll with the ocean's surface swell. Dolores Chouest rode just ahead, already positioning herself to take him aboard up her docking well aft.
The Dolores Chouest was an ungainly looking vessel, with bright red hull and buff-painted superstructure, her bridge mounted far forward, above her bow, and with side-by-side stacks amidships. Aft, her stern was split in a deep U, with a lift designed to raise small submersibles out of the water. The Dolores Chouest, a civilian vessel under long-term charter to the Navy, had originally been configured to serve as a support vessel for DSRV rescue submersibles, but was now serving as the mobile home base and mother ship for the XSSF-1 as she completed her sea trials.
"Manta, Dolores," crackled over his radio headset. "We have you in sight. Welcome home."
"Copy that, Dolores. Spread your legs, I'm coming in!"
"Roger that, big boy. Please be gentle."
Docking the Manta wasn't as simple as cutting the engine and drifting up to a dock, with sailors ready to toss him a line. As soon as he cut power, he would begin to sink, so he had to carefully gauge his approach, coming in under power just barely fast enough to stay afloat. To help him maintain his critical speed, the Dolores was motoring away from him at ten knots. As he made his docking approach at fifteen knots, his actual closing speed was only five. At the last moment he touched the screen control to fold the fighter's water-foils and increased speed slightly to compensate.