They'd been running at full speed for ten minutes and the range to the U-Boat was down to three miles. The Old Man silently blessed his ship's old-fashioned reciprocating engines. The low-frequency thump they generated travelled for hundreds of miles through the ocean, but to a listening U-Boat hydrophone operator it could easily be confused with the endless pulse of the Atlantic's waves. The scream of turbines might only be audible to a surfaced submarine at three or four miles, but what it screamed was "warship!" HMS Leven was well within gun range of the submarine now, but he wanted to get closer. His 4" mounts fired under local control only; they didn't have the elaborate computers and plotting tables of a big warship, or huge rangefinders mounted high on an armoured tower. A U-Boat was a small target, and if his guns missed he wanted to be close enough that when she dived he could pick her up on ASDIC and run down on her before she could evade. According to the book he was close enough now, but he no longer trusted the book. If he could get within two miles that ought to do it; even if the U-Boat dived Leven would be over her last known position before she could hope to get out of ASDIC range from there.

A voice pipe demanded his attention. "Radar to bridge, first contact directly on the bow at 4,400 yards. Second contact Green Three-Fiver, range eight miles, probable U-Boat." The Old Man acknowledged and crossed quickly to the chart table. Right, the second U-Boat couldn't fail to hear the gunfire when Leven began her attack. That would leave her with two choices; she could keep going on the surface, in which case he could hunt her by radar, or she could dive. If she dived she'd be able to get away before he could close on her, but by taking up station east of her last reported position he could use ASDIC to keep her away from the convoy. Submerged, she could never catch up; on the surface Leven's radar would have her. If she tried to move east she'd eventually come within ASDIC range and he could attack with depth charges and the Hedgehog. That would keep two of the three U-Boats away from the convoy; Viperous and the two corvettes should be able to handle the third.

He returned to his position at the front of the flying bridge and flipped open the voice pipe. "Bridge here; what's the range to the first target now?"

The reply was immediate. "Four thousand, Sir."

"Very well." Next he opened the pipe to the wheelhouse, immediately below him, flicking on the intercom to the 4" gun mounts at the same time. "Bridge here. Come round to new course zero degrees, maintain full ahead."

"Aye aye, Sir!"

The Old Man closed the pipe and pressed the button on the gunnery intercom. "Guns, bridge. A and Y guns, train to Red Three-Zero, on my command one round of starshell each at 4,000 yards then independent fire at identified targets." He waited for the acknowledgement as Leven came round to due north. As soon as she had straightened up on her new course he pressed the button again and said one word. "Fire!"

He didn't even hear Y gun, the after mount; its report was drowned out by the crash of A gun, thirty feet in front of him on the shelter deck. He shook off the effect of the blast and raised his binoculars. Four seconds later and two miles off the port bow the starshells cracked apart and released their flares, bathing the sea in a harsh yellow glare. Pinned in the middle of the sudden light was a low black silhouette; the U-Boat. A moment later both guns fired again. Four seconds for flight, then this time two columns of water erupted near the distant submarine. Seconds counted now; she'd go down fast, probably within twenty seconds. There would only be three or four chances for each gun to score a hit. Yes, there she went…

The racing U-Boat's bows rose slightly on a swell, dipped into the trough and didn't come up again. A second later white foam exploded from the front of her conning tower as the sea rushed up the deck. Her gun disappeared below the surface as another pair of 4" HE shells bracketed her, the conning tower already half submerged. Leven's guns fired again, Y slightly ahead of A this time. Water spurted skyward in front of the U-Boat, then the white pillar broke apart and fell back, obscuring her for a moment. When it was gone there was only a swirl of water on the surface. She was down. Seconds later two more shells splashed uselessly into the ocean.

The Old Man ordered Leven back to 330 degrees - directly towards where the U-Boat had dived - and waited as the minutes ticked away. The ASDIC set had a range of about 2,000 yards and it would take the U-Boat nearly eight minutes to get that far from her last known location. Leven would be there in five and a half.

In the event, it was less than two and a half minutes before the voice pipe from the ASDIC hut came to life. "ASDIC to bridge, strong contact dead ahead, range 2,000." The Old Man frowned. That was right where she'd gone down. He wondered about the salvo that had landed just before she vanished. He'd seen only one splash; could the other have scored a hit?

"ASDIC to bridge, contact dead ahead, range 1,000." No, she wasn't moving. Well, if she was going to move she had about a minute left to do it in. He switched the intercom to the torpedo officer's position aft and ordered him to stand by to fire the Hedgehog and depth charges at ASDIC's direction. With the water foaming under her bows HMS Leven ran down on the stationary U-Boat. The bridge searchlights came on, their beams illuminating the patch of water over the contact. Seconds passed as ASDIC read off the falling range. When it reached 250 yards the Hedgehog fired with a series of thuds, and 24 bombs arced forward and splashed down around the contact. Seconds later two eerie green flashes lit the black ocean. Hits! Two hits! That should be enough to disable a submarine. Then ASDIC called "Lost contact" and they were over the patch of disturbed water. Two depth charges rolled off the stern rails, the throwers that lined the afterdeck coughed out a fan of four more on each side of the ship and, a moment later, a final pair dropped from the rails. The U-Boat was now surrounded by a rough circle of twelve sinking charges, as Leven raced away from the imminent blast.

The sea jumped behind them, flaring green and shuddering violently as the charges went off, then a massive area erupted skywards in white foam. By the time it crashed down again Leven was 400 yards away in a hard turn, with her searchlights swinging to track the blast site and her captain intent on dropping another pattern of charges into the chaos. It would be a quarter of an hour before ASDIC could pick an echo out of the roiling, bubble-filled water where the huge weapons had exploded, but that didn't matter; they would drop again, in the hope that the U-Boat was still there. At both ends of the ship torpedo ratings struggled to reload, hauling the great cylindrical depth charges on to the throwers and sliding more bombs over the array of rods that gave the Hedgehog its name. Half way through the turn, though, it was her guns that opened fire. First the Oerlikon on the port bridge wing, spraying a shower of empty brass cartridges onto the Old Man's mattress, then a second later every weapon that could bear blasted out.

Pinned in the glare of the two searchlights, the U-Boat's bows projected from the sea at an acute angle. 20mm tracers whipped the water around the black wedge into a froth and cracked against the tough hull, then came a bright flash as Y gun scored a direct hit. The U-Boat began to settle, her conning tower emerging from the water as her bows came down, but the Old Man was yelling at the helmsman to centre the wheel. Leven straightened up and both her main guns could now fire over open sights at a stationary target barely a quarter of a mile away. Within ten seconds at least three more hits flared on the submarine, then her bows rose up once more and, with shocking speed, slid down into the sea.

- X -

FOR CLYDESPR UBOAT SUNK BY DC AND GUNFIRE AT 54 39N 29 42W RECOVERED 3 SURVIVORS BREAK SECOND UBOAT DETECTED BY RADAR AT 54 43N 29 39W BUT HAS NOW DIVED AM SEARCHING LEVEN SENDS JW

She sagged back in her chair, relief swamping her for the moment. The little warship had survived the first fight and reduced the odds against her by half; the third U-Boat was probably too far to the north for Leven to intercept. She wrote another slip for the Wren then contemplated the red curves on the plot just east of the distant battle. That looping line marked the extreme range of the RAF Liberators. She wondered how she could arrange to get an aircraft over them at first light.

The SOO poured herself a cup of tea from the electric urn and watched as the plot was updated. Leven's marker and one black circle moved, another black circle marked with a chalked white cross. In the Atlantic the frigate raced north towards a U-Boat that, dived and hunted, would be preparing to strike at its pursuer. A sudden desperate loneliness struck her in the warm and crowded Plotting Room. She sipped the hot tea and shivered.

Author's Note - I have found various contradictory sources on the names of the River-class frigate's gun mounts. A few call the 4" guns B and X, and assign A and Y to the Hedgehog launcher and depth charge rails instead. Some call them B and Y, classing the Hedgehog as a mount but not the depth charge array. I have chosen to go with the others, which call the guns A (furthest forward) and Y (furthest aft) and don't count the ASW weapons as gun mounts. If anyone has a definitive answer please let me know.