“Cut ramjet!” Carr ordered.
Lieutenant Junior Grade Rockford carried out the command. Carr watched as the speed of the D dropped. The submarine had a deceleration rate of two knots a second. It had been traveling at seventy-seven knots when it turned. That had knocked fifteen knots off the speed. But they were still heading toward the bottom rapidly, with the ramjet shutting down gradually. If they killed it immediately, the sea would rush in where the Egg had been and slam the submarine. It would be the equivalent of wind shear to a small plane, but across every meter of the hull—top, bottom, and sides.
“Mike, they’ve got to change course,” Dr. Patrick Drake said urgently. Drake was the Ant Hill geologist.
“Give them the new coordinates.” Carr did not ask the geologist why. There wasn’t time.
“ D helm, alter five degrees southwest at once,” Drake said.
“Port mobility negative!” Rockford replied.
“Vent all starboard ballast into bubble,” Colon commanded. “Draw psi at three per second.”
That was smart, Carr thought. Putting water into the air pocket would create drag on that side. Adding water at the rate of three pounds per square inch every second would keep the hull from being crushed.
“Increase ramjet deceleration to three knots a second,” Colon said. “Adjust working stabilizer to compensate for skew.”
The faster deceleration would be pushing hull tolerance, but not outside the theoretical safety zone. The variable in all that was the addition of pressure from the emptying ballast. The team’s structural engineer, Dr. Otis Fargo, was already working those computations. He flashed Carr a thumbs-up—then suddenly frowned and raised his other fingers in a “stop” sign.
“That maneuver won’t allow the bubble to be depleted in time,” Dr. Fargo said gravely.
“In time for what?” Carr asked. The scientist did not mute the speaker. He wanted the captain to hear the conversation.
“The ramjet pocket is going to hit the ice shelf at roughly thirty-one percent full capacity,” Dr. Drake went on. “That could provide a shock wave sufficient to bring the shelf down.”
“That isn’t entirely bad news,” Dr. Fargo remarked.
“Why?” Carr asked.
“Having the air pocket in place, partially intact, will ease the blow to whatever section of the D impacts the ice shelf,” Fargo said.
“If there’s an avalanche, what part of it will we catch?” Colon asked.
“There’s no way of knowing,” Drake said. “We aren’t certain how fragile the subsurface sea ice is in that area.”
“Is there a better spot to impact a degree or two in any direction?” Colon pressed. “Less rock, more silt, shallower ice—?”
“We don’t know,” Fargo said.
“Wouldn’t a deeper contact-point be marginally better?” asked Dr. Adler Davenport, the oceanographer. “If ice does fall on the D and drives it down, the underside would take less stress if there was a cushion of water.”
“Wouldn’t a lower impact also dislodge less ice?” Carr asked.
“Yes on the first question, no on the second,” Fargo replied. “Having the air pocket hit the slope even lower could be disastrous. If the bottom section were to give way, that might weaken the ice wall immediately above it, but not bring that down until after the D has come to rest.”
“Burying it,” Davenport said.
“Or worse, crushing it,” Dr. Drake noted.
“Gentlemen, thanks for the input but I’m riding this puppy down with the Egg as is,” Colon said. “I want the cushion.”
“You’re go on that,” Carr said.
As the scientists waited, Drake pointed to a map on his monitor. It showed sonar readings from the Abby ’s previous voyage. “The ice shelf slopes dramatically toward the shore above them. That section of the offshore region may not be affected by a concussion below. The captain is correct. It’s better to allow the ramjet to blast the lower ice loose, create a kind of nest, before they hit.”
It was slightly absurd to Carr that they were discussing options that would lead to a result that would probably not matter. Whether the submarine crashed or was buried, the D would probably be crippled. And even if it came to rest relatively intact, what would they do next?
It was also strange that no one had said anything about the Abby. The feeling, Carr guessed, was that no one was “as” concerned because the rear admiral and his team were above water. They assumed that was a safer place to be. But even a surface wreck, in the antarctic, was as much a potential death sentence as the underwater drama they were witnessing.
Everyone in the room was very still. There was nothing to do, no simulations to run, no numbers to process, no more options to consider. Carr didn’t even second-guess what any of them had done, from insisting that the towline be attached to the present. All of that would come later. Right now, they were waiting to find out just one thing.
Whether they still had a submarine and a crew.