A bay pilot spends his nights guiding massive ships through the bay's tricky waters

It is 9 p.m. on a cold January night. Capt. Al Watts climbs the rope rungs of a ladder to board the cargo ship that sits in the harbor loaded with 5,000 cars that range from Chryslers to Mercedes. Watts, who has 38 years of experience in nautical navigation, takes command on the bridge of the Equuleus Leader docked at the pier in Seagirt East Channel. The bow thrusters churn beneath the shadowy water, awakening the still harbor with reverberations. "Dropping lines, Dundalk 2," Watts says into the radio, alerting all vessels in the harbor that the ship is getting underway. He has been shuttled from shore to ship in a small boat in order to take command, temporarily, and turn the giant vessel 180 degrees in the tricky 1,600-foot-wide basin, steering it into the main channel.

Watts is one of the 60 Maryland pilots who provide the safe passage of ships longer than three football fields that travel the harbor importing and exporting goods along the Eastern Seaboard. During any given week, the Port of Baltimore sees 40 to 50 ships from all over the world. The Maryland pilot comes aboard to take over for the ship's captain to provide local knowledge. All ports have their compositional temperaments that require regional experts to navigate, especially in confined waters. The floor of the Chesapeake Bay is constantly shifting and shoaling up in different areas. Most of a ship's size is what isn't seen, what runs below in the darkness, the 47 feet of steel that hovers inches above the 50-foot bottom of water. In the shallow depths a ship's wake has nowhere to go, making the pilot's expertise in ship handling crucial to avoid speeds and obstacles that could run the ship aground or overrun Baltimore Harbor with waves that would excite the most renegade of surfers.

Piloting gets trickier when docking and undocking these metal Goliaths against wooden piers, some of which haven't been lengthened since the days of steamships in the early 1900s. Watts specializes in dockings, which are mostly done at night so the ship can be stationed in time for longshoremen to operate the cranes that load and unload cargo during the day. Vigilance and night vision are just as integral for a pilot as the radars and radios Watts operates from the bridge to coordinate the ship's movements with the assistance of a tugboat.

"You're constantly checking your position and watching how the ship is setting from left to right," Watts says. "When you get ready to make a move you give everybody out there a head's up. They'll give you a holler back to work out passing arrangements."

Watts takes the Equuleus Leader steady around the Seagirt terminal.

"Back 'er easy," he radios as the ship pulls away from the dock to turn around. "And just a little easy."

"Tug'll be comin' right up on you," the tugboat captain, Wayne Browning, answers back. "We'll be as easy as we can."

Despite its 59,000-ton weight, the Equuleus Leader glides counterclockwise without splashing up water as if it's rotating on glass. Watts guides the ship sideways as the tug pushes against her stern to help rotate the bulk of the ship from the back.

"And we're gonna give her a stern bell," Watts radios. His command directs the ship to increase propulsion astern and also alerts the tug to take precautions to avoid being sucked around the ship's propeller wash, or current of water.

The Equuleus Leader completes the 180-degree turn and straightens out to chug forward into the main channel. The tugboat captain radios Watts. "Looks like we're finished. Was a fine job as always, Captain," Browning says.

"It was a back, spin, and go," says Watts.

The tugboat pulls away and Watts hands the ship over to the next pilot who will navigate it 10 hours down the Bay to Cape Henry, Virginia. He descends the rope ladder while the ship motors through the channel toward the Key Bridge. Christine Cleary, a trained launch driver, maneuvers a small boat to stay parallel to the moving mountain of a vessel. She's Watts' ride back to land where he'll wait for his next job at midnight.

Given the nature of shipping, which revolves around estimated arrival and departure times, pilots stay on the ready to be dispatched to the next ship like firefighters called to duty.

"You're up, you're down; you're here, you're there," Watts says. Sleep is a rare gift limited to naps—at best—between jobs. As Watts puts it, "You fall down when you can." Check out the gallery here.