Night Patrol Boats Aid Israel’s Coast Defense : Terrorism: Missions in the Mediterranean are the type that American forces may be called on to perform in the Persian Gulf region.

The young Israeli skipper eased Patrol Boat 814 away from the pier at Haifa Naval Base at 4:30 p.m. and backed into the channel, the boat’s twin diesels responding to the throttle with a deep-throated murmur.

Once clear of the harbor, the skipper, a 24-year-old lieutenant named Hagai--under the rules, he cannot be further identified--headed the 65-foot boat toward the lowering sun and opened the throttles. Quickly, the speed increased to 33 knots, more than 35 miles an hour. The bow sent up a wave of spume as it banged into the choppy sea.

Fifteen minutes later, as Patrol Boat 814 headed for the area off Lebanon--on the kind of patrol American sailors may soon be called on to duplicate in the Persian Gulf and Red Sea--general quarters was sounded.

The dozen crew members donned helmets and flak jackets and manned the two 20-millimeter guns at bow and stern and lighter machine guns on either side of the bridge.

The boat slowed, a floating target was dropped overboard, and each crew member took his turn firing the guns. They also fired their Galil assault rifles. Also on board are a rocket launcher, flares, depth charge racks and a Zodiac rubber boat.

Satisfied, Hagai ended the drill and set a northerly course for patrolling the Lebanese coast. The vessel was one of several Israeli boats on duty this evening.

The 814 is a boat of the Devora class, an updated, faster and more powerful version of the Dabour, which was developed by the U.S. Navy as the river patrol craft PBR, for use in Vietnam.

“We have been pretty successful at keeping terrorists off our beaches,” Hagai told a passenger. “But this creates a problem for our crew: How do we keep our edge night after night? It’s not easy staying alert and operating in total darkness.”

To enliven the evening, 814 sped past Nahariya, a resort town, and the crew scanned the beach through binoculars for the sight of topless French bathers. But it was too late in the day.

The 814 slowed at the Lebanese border, marked by a rugged outcropping of rock called Rosh Hanikra, and nosed in close to the shoreline to chat by radiotelephone with the crew of a radar station there.

The station’s duty officer, a woman, would be the 814’s controller this evening. Her radar monitors sea traffic off southern Lebanon, and she directs the boat toward targets. With a friendly toot on its siren, the 814 headed off again toward the north.

As the sun dipped into the sea, the 814 was buttoned up: no running lights, no smoking on deck, blackout curtains in the Combat Information Center and in the crew’s quarters.

“We have established a sea curfew after dark in this area,” Hagai said. “So anyone we find here shouldn’t be here. That’s the way we are trying to keep our own people safe from seaborne assault.”

The crew members, all younger than Hagai, all in green fatigues, seemed to enjoy the first hours of the patrol, as they prowled north past the United Nations complex at Naqoura and came within easy visual range of ancient Tyre, before turning and heading south again.

They crowded the bridge, searching the darkening sea for rubber boats of the sort favored by Palestinian guerrillas trying to get ashore in Israel.

The search is conducted by radar, too, not only with the shore station’s equipment but also with the radar on the 814. And atop the mast is the Starlight Scope, which gives the viewer an almost daylight view of the surrounding sea.

These days, as a consequence of months of tight screening, the patrol boats rarely find anything resembling a hostile target. Four weeks ago, another patrol craft sank a rubber boat, killing its two occupants. Navy officials said they were would-be infiltrators.

“We get a lot of flights of birds, particularly during migratory season,” Hagai said. “The signature (on the radar screen) of a couple of dozen birds skimming the water comes across about the same size and shape as a fast-moving boat. So we have to keep checking.”

In the galley, the chef, a 20-year-old volunteer named Shachal, was preparing schnitzels and blinis and chocolate cake.

“The crew likes meat and french fries and sweets,” Shachal said as he mixed batter for the blinis. “They don’t like salads and sour things because it ‘s bad on your stomach on these boats.”

Seasickness is almost endemic and nothing to be ashamed of. The patrol boats are tossed wildly in even a moderate sea.

“If you have to throw up,” Hagai said, “you just do it--and continue with your work.”

Oil on the decks makes the footing doubly difficult.

“We keep our weapons and other gear clean with plenty of fresh lube oil,” a crewman said. “The guns come first.”

Throughout the night, the 814 cruised up and down the coast, sometimes slowly, sometimes roaring along with the crew at general quarters when alerted to a target (all of them proved to be birds).

Shortly after dawn, the patrol boat headed back toward Haifa but was diverted by a report of an unidentified small craft.

Hagai called the crew to general quarters and ordered flank speed, nearly 37 knots, which sent spray over the bridge. The crew slapped on helmets and jackets and manned the guns as the 814 circled the suspect craft, which, as it turned out, was manned by three fishermen.

They checked the boat’s identification number by computer, and, when it proved to be valid, the 814 bade the fishermen farewell and headed for the barn.

At 6:30 a.m. the 814 slid into its berth, another jouncing, 14-hour night patrol completed. Hagai prepared to debrief the crew members, and they would spend another three hours cleaning up the boat.

“Even though we didn’t make any enemy contact, this makes us feel good,” he told the visitor, “because it means we have done our job. Nobody last night was trying illegally to get into Israel by sea.”