Sea of Shadows eBook - Navy Thriller.com

294 JEFF EDWARDS
Captain Vargas shrugged. “I don’t know. I think I said something
about the sub blending in with the oil platform’s sonar return.”
Sherman snapped his fingers. “Not the oil platform, the bottom.”
“You think the sub is sitting on the bottom?”
“Could be, Skipper.”
“Wouldn’t sonar have picked him up when we ran over the top of
him?”
“No, ma’am,” the USWE said. “The SQS-53D’s automatic gain
control clips the bottom return out of the signal when it processes it. If it
didn’t, the system would show a sonar return in all directions; our scopes
would be saturated. If the sub is sitting on the bottom, his signal could be
getting clipped out along with the bottom signal.”
“Can we just shut the automatic gain control off, or bypass it?”
“No, ma’am. The bottom return would saturate our scopes, and we’d
be completely blind.”
The captain stared at him. “You’re telling me that the American people
spent millions of dollars on a sonar that refuses to see the submarine?”
“I’m afraid so, Skipper.”
“And that submarine could be directly underneath us at this very
second?”
“That would be a hell of a coincidence, but yes, ma’am. It’s certainly
possible.”
“There’s a case of our tax dollars hardly at work. Can we call him up
on the underwater telephone and invite him to come out and play?”
Lieutenant (jg) Sherman’s eyebrows went up. “That’s not a bad idea
…”
“Great,” the captain said, her voice dripping with sarcasm. “Now all
we have to do is find someone who speaks German.”
Sherman smiled. “Actually, Skipper, what we need is someone who
speaks Submarine.” He keyed his mike. “Sonar—USWE. Does your On-
Board Trainer’s sample library contain a recording of a Mark-54 torpedo?”
“USWE—Sonar. Yes, sir. It does.”
“Sonar—USWE. Can you patch an audio signal from the OBT into the
underwater telephone?”
The reply took several seconds. “Uh … yes, sir. I guess so. Is that
what you want me to do?”
“Affirmative, Sonar. Go ahead and rig the patch and load the Mark-54
recording, but do not transmit until I give the word.”
“Sonar, aye.”
The captain nodded slowly. “You’re going to broadcast a fake torpedo
signal and scare the sub off the bottom?”