The man who can halt the hurtling traffic of the Capital Beltway with the turn of a single crank, who is lord of navigation for a stretch of the Potomac River, had an unusually busy morning yesterday.

The phone kept ringing in his solitary perch - a glass-walled, soundproof, air-conditioned tower overlooking the Woodrow Wilson Bridge 108 feet above the river. Crowd gathered nearby.

The Coast Guard Cutter Eagle, a 295-foot-long, square-rigged sailing ship was coming up the river on its annual training cruise and it was James W. Elrod's job as bridge operator to raise the massive draw span and let her through.

Elrod, 36, is one of four persons employed by the D.C. Transportation Department to operate the bridge, one of the most heavily traveled thoroughfares in the Washington area, which carries Beltway traffic across the Potomac between Alexandria and Prince George's County.

The phone calls were from radio stations wanting to know if the Eagle was in view. The crowds, straining for a glance of the huge sailing ship, gathered at Jones Point on the Alexandria side.

Elrod scanned the Potomac with his binoculars and grumbled: "Coast Guard calls every damn thing they got a cutter. It's probably not a cutter, but they call it that."

Elrod had already operated the drawbridge to permit a small ship to head downriver to meet the Eagle. He had talked to its skipper over the ship-to-shore radio, but much of the traffic on the river isn't equipped with radios.

Any boat with a mast 45 feet or taller must have the bridge opened before passing through. Sailboats are usually required to move in circles at the bridge until the operator spots them.

By habit, Elrod looks up after each chapter of whatever he is reading to see whether a sailboat captain wants his attention. On his desk yesterday was H. Rider Haggard's "She and Allan." Elrod says he's able to read four or five books a week, but there was little time to read with the Eagle coming.

Elrod had time to talk about the quality of the bridge: It's in disrepair.

Metal plates that motorists commonly think are covering potholes actually cap gaping holes over the water. "Couple more patches and soon there won't be a bridge, just a lot of patch," said Elrod.

He also says the traffic gate on the Maryland side is broken. Only a red light warns Virginia-bound traffic to stop before reaching the sharply-tilted open draw span. If someone decided to run the red light, "he'd be very dead," Elrod remarked.

"You feel bad when it's not all here," he remarked. "It's like your little finger cut off when something doesn't work."

Bridge maintenance is complicated by a quirk of geography. The span lies in three jurisdictions - the approaches are in Virginia and Maryland, and the center, including Elrod's tower, is in the District of Columbia. The District operates the machinery that opens the draw, Maryland takes care of repairing the bridge structure, keeps the roadway clear of snow, and paints, and Virginia supplies the bridge with water and electricity.

If there is an accident on the bridge, Elrod calls the appropriate police department, depending on where the accident occurs. "The Maryland State Police usually get there pretty fast," he said, while the response on the Virginia side is slower.

More than 100,000 cars use the bridge each year, making it the second busiest span in the area (the 14th Street Bridge ranks first). The bridge is opened five or six times a week, and Elrod feels that sailors demanding that the span be raised don't realize how much traffic backs up as they meander through. But the commuting motorist is protected. Rules forbid opening the bridge during the morning and evening rush hours.

The Eagle would have had to wait during rush hour, too, but Elrod didn't spot her with his binoculars until 10:12 a.m. Radio contact came 23 minutes later, and at 10:43, Elrod, standing at a console, went through the 10 steps necessary to raise the draw.

As a result, traffic on each side of the bridge was stopped. The locks holding the span closed were opened, the latches holding it down unlatched. Elrod released the brakes and the bridge's four leaves began their ascent as four enormous counter-balances below the roadway descended. The contraption squealed.

The Eagle moved through under diesel power. Coast Guard cadets stood in her rigging, some of it as high as the top of the drawbridge leaves, 160 feet above the water.

"Just waiting for the sucker to go through so I can close up," Elrod muttered. He was worried about a trail of some 15 boats behind the Eagle and the motorists who had left the safety of their cars on the bridge to watch.

"Come on, get through there," he remarked as the straggling boats passed through and traffic backed up to the Oxon Hill entrance ramp.

Elrod returned to his desk and logged the draw closed at 10:59, a full 16 minutes after it opened.

"Damn, that was a long opening," he said. CAPTION: Picture 1, The Eagle passes through the Wilson Bridge with crew members on deck and yards. The control tower is to the left of the raised spans of the bridge. Photos by James M. Thresher - The Washington Post; Picture 2, In the operator's tower, Elrod uses binoculars to scan the Potomac for the Eagle; Picture 3, With both hands firmly on the controls, bridge operator James Elrod releases the brakes holding down the four leaves of the drawbridge; Picture 4, The 295-foot-long Eagle docks in Alexandria after passing through the Wilson Bridge.