water that doused him. Although the cavern was pitch-black, he took the first deep breaths he’d enjoyed since losing the use of the periscope.
“How’s that?” Mercer asked from below.
“Heaven,” he sighed, fingering water from his glasses.
Within a few minutes, Ira fired the port diesel. The engine ran rough from fuel contamination and tar-thick oil, but he felt he could keep it running long enough to reach Iceland. Mercer went ashore to check the cavern, finding it much as he’d predicted. There was no evidence that anything man-made had ever been in the chamber, and all the alcoves were blocked with debris. Boulders and loose rock from the entrance tunnel spilled far onto the main floor, indicating a great deal of its length had been dynamited. He was confident that Rath and his men had collapsed a similar amount of the tunnel near the surface.
If they couldn’t negotiate the sub through the zigzagging underwater channel, they would die here in the darkness. He returned to the U-boat to help Ira fill the battery cells with acid. Once they recharged — if they recharged — they would be ready to leave.
After an hour of noxious work in the cramped aft battery room below the galley, Ira announced that they were in trouble.
“Considering our circumstances, you’re not telling me anything new.” Mercer’s eyes streamed tears from the caustic fumes.
Lasko’s normal humor had abandoned him. “I mean real trouble. Most of these batteries are worse off than I thought. The ones taking a charge leak like sieves. Once we close the hatches, the sub’s going to fill with chlorine gas a lot faster than I anticipated.”
Mercer tensed. “How long do you think we can stand it?”
“Depends on the individual. But after an hour or so the boat’s gonna be a coffin ship.”
“Can you rig some breathers for us?”
“I can, but that’s not the problem. With acid eating into the functioning batteries, the boat’s electric motor will lose power long before the first of us checks out. Have you figured out how long it takes to get through the tunnel and out to open sea?”
Mercer’s expression darkened. “According to the captain’s log, about an hour and a half.”
“Figures,” Ira said sourly.
“All’s not lost. All we have to do is push our speed over what he wrote to shave off some time. It won’t take me long to make corrections in the timing of our turns to compensate.”
“You’re forgetting that his figures are based on traveling a certain amount of time at certain RPMs before making a turn. Back then his boat was loaded with stores and a crew of fifty. We’re at least a hundred tons lighter, which will make us faster. I can double the RPMs but that won’t necessarily mean that you can halve the time.”
“I hadn’t thought of that,” Mercer admitted. “Any suggestions?”
“Factor in a speed difference of about half a knot faster than the captain used and hope to Christ you’re right.”
“What do you mean ‘hope
Ira smirked. “I don’t want the others blaming me when we plow into a tunnel wall because we missed a turn.”
It took a further two hours to get ready. Once the batteries were charged and any electrical faults repaired, Ira made certain that the air tanks were topped to their maximum pressure tolerance. Using the diesel, they swung the antique away from the pier and lined up with the entrance to the submerged channel out of the cavern. Hilda and Anika would operate the planes while Marty was at the helm to control the rudder. Ira had stationed himself at the ballast control. Mercer stood at the plotting table, where he could watch the gyrocompass. On the table were a pair of dividers and the captain’s log, which lay open to the chart of the submerged passage. The rough sketch of the tunnel showed a twisting tube filled with numerous obstacles the sub would have to avoid as it wormed its way to the outlet in the fjord.
“We’re in position,” Erwin called from the conning tower. He had noted their distance off the dock using the attack scope’s range finder.
“You know what you have to do,” Mercer shouted back up to him.
The scope sank back into its mount and a second later Erwin sealed them in. This time he actually walked calmly to the bathroom and had time to close the door before he began retching.
Without the pounding throb of the diesel, the boat was remarkably quiet.
“Chlorine gas is already starting to build up,” Ira said, though it would be a while before they would smell it.
Mercer consulted his chart, noting how sharply the cavern floor had dropped off from the pier. “Ira, make your depth sixty meters. Helm steady. Planes at neutral.” Mercer thought he sounded like an actor in an old war movie, but his crew responded to his orders without question.
“Hold there, Ira,” Anika called, her eyes riveted to the fathometer at her station.
“Gotta tell me earlier or else we’ll sink past our target depths,” Ira said, compensating for the mistake.
“Aye, aye. Okay, depth sixty meters.”
“Here we go, boys and girls.” Consulting his revised propulsion figures, Mercer spoke crisply. “Give me ninety RPMs for ten minutes starting” — he checked the ratcheting second hand on his TAG Heuer — “now!”
Silently the U-boat began to creep across the lagoon, a washing hiss sounding through her hull as she cut the water. “I’ll need two degrees up on the planes when I give the command in about five minutes.”
“We’re ready,” Anika said.
“I’ll be damned, Chief.” Mercer grinned, momentarily overcoming his uneasiness. “You actually did it. You got this thing going.”
“Don’t thank me. Wolfgang Rossler’s the man we owe our lives to. If the Nazis had had a few more like him, they could have won the war on maintenance alone.”
When it was time, Mercer gave the order to raise the bow planes to reduce their depth. Ira asked if he should vent water from the tanks, but the log indicated that this maneuver was done only with the planes. After another five minutes the tunnel took its first turn to the right.
“Marty, steer right ten degrees. I’ll tell you when to ease off.” This was a shallow turn in what the chart said was the widest part of the passage. Mercer wasn’t concerned about hitting anything yet. That fear would come later. He watched the compass next to him. “Okay, ease her back. A little more. That’s it.” He let out a breath. “Increase to one hundred and thirty revs and prepare for a hard turn to port in two minutes.”
They were well inside the sunken conduit, surrounded on all sides by rock and ice. A miscalculation in any direction would kill them all. No one knew if the tunnel was still wide enough to allow the sub passage, so they were forced to crawl along blindly, unable to reduce their speed because of the chlorine gas filling the bilge.
“Marty, coming up is a ninety-degree corner, so bring us to port as fast as you can spin the wheel. Now! Anika, ten degrees down on the planes. Make your depth eighty meters.”
“That’s two hundred and fifty feet,” she said. “Can this old hull take it?”
“We’ll know in a minute.”
Creaking like a sailing ship caught in a typhoon, the U-boat spiraled deeper into the abyss. Her moans reminded Mercer of whale song. “All right, straighten her back out. Reduce RPMs to one hundred. We’ve got a long stretch at this depth. Make sure she doesn’t drift.”
Like steel nails drawn across a chalkboard, the U-boat scraped against the side of the tunnel. The impact made them clutch their seats. The sub veered away from the wall and then drifted back again, harder, the hull plates screaming. Dislodged rocks hit the hull like cannon fire.
“Shit! Marty, bring us to starboard two points.” The unholy screeching died as soon as Bishop spun the wheel.
“What happened?” Erwin cried. He’d run into the control room at the first impact, too scared to remain in his bunk despite his claustrophobia
“We needed to scrape some barnacles off the side of the boat,” Mercer replied. “We should be back in our lane again. Marty, bring her back to eight degrees magnetic.”
“You did take the North Pole’s drift into account, didn’t you?” Bishop asked.
“And the fact we’re moving with the current, which according to the chart runs at two knots.”
