frigate's SH-2F Sea Sprite helicopter sped off north, her magnetic anomaly detector trailing out by cable from a shroud on the right side of the aircraft. Essentially a highly sensitive magnetometer, it could detect the disturbance in the earth's magnetic field made by a large chunk of ferrous metal--like the steel hull of a submarine.
"Signal on number six is now medium-strength. Signal on seven remains medium." The plotting team took this to mean that the submarine was heading south.
"1 can give you a working range figure," ASW said to the TAO. "Forty-two to forty-five thousand yards, bearing three-four-zero to three-three-six." The frigate relayed this at once to the Orion.
As they watched on radar, the P-3C quartered the area, flying very precise tracks across the box of ocean defined by Pharris's sonar data as the probable location of the submarine. A computer system plotted the lines as they extended to the south.
"Pharris, this is Bluebird. Our data indicates no friendly subs in the area. Please confirm, over."
"Roger that, Bluebird. We confirm no reports of friendlies in the area." Morris had checked that himself half an hour before.
"Signal strength increasing on number six. We now have a weak signal on number five. Number seven is fading out." The technician was really struggling to be professionally impassive now.
"Range is firming up. Estimate target speed roughly eight knots, distance forty-three thousand yards."
"Transient! Transient!" called the ship sonar operator. A metallic noise had come from the target bearing. A closing hatch, a dropped tool, an opening torpedo tube door--something had made a uniquely man-made sound.
"Confirm mechanical transient, copied on buoys five and six," the aircraft called immediately.
"Confirmed," Pharris's TAO answered. "We got that on the towed-array, too. We evaluate the contact as positive submarine at this time."
"Concur," the Orion replied. "Positive Redboat classification--madman! Madman, madman, smoke away! We have a MAD contact." A big spike appeared on the MAD readout. Instantly, a crewman flipped a switch to deploy a smoke marker and the aircraft turned hard right to circle back on the contact point.
"Plotted!" The tactical action officer marked the position on his tactical display scope with a large V symbol.
The helo raced in on the contact as the Orion circled back.
"Madman!" its systems operator called out, and the helo dropped its own smoke bomb, slightly south and west of the Orion's.
The data was now being relayed to the frigate's torpedo-tube and ASROC attack directors. Neither had anything like the range to engage the target, but that could change quickly.
"Patience," Morris breathed from his chair in the CIC, then louder: "Take your time, people. Let's lock this guy in before we fire."
The Orion's tactical coordinator agreed, forcing himself to relax and take the time needed. The P-3 and the helicopter made another MAD run north to south. This time the Orion got a reading and the helo did not. Another run, and both had the contact's course line. Next came an east-to-west run. At first, both missed, but on the second run both had him. The contact was no longer an it. Now it was a he, a submarine being driven by a man. Control of the operation now passed exclusively to the tactical coordinator on the Orion. The big patrol aircraft orbited two miles away as the helicopter lined up for the final pass. The pilot made a very careful check of his tactical display, then locked his eyes on the gyrocompass.
The helo began the last MAD run, with the Orion two miles behind it.
"Madman, madman, smoke away!" The final smoke marker dropped, a green flare floating on the surface. The Sea Sprite banked hard to the right to clear the area as the Orion came in low. The pilot watched the smoke's movement to figure wind drift as he lined up on the target. The P-3C's bomb bay doors opened. A single Mk-46 ASW torpedo was armed for launch.
"Torp away!"
The torpedo dropped cleanly, its braking parachute trailed out of the tail to make sure the weapon entered the water nose down. The Orion also dropped an additional sonobuoy, this time a directional DIFAR.
"Strong signal, bearing one-seven-niner."
The torpedo dove to two hundred feet before beginning its circular search. Its high-frequency sonar came on as it reached search depth. Things started happening quickly.
The submarine had been oblivious to the activity over her head. She was an old Foxtrot. Too old and too noisy for front-line operations, she was there nonetheless, hoping to catch up with the convoy reported to her south. Her sonar operator had