ERIN TSCHANTRET, HANDS hands on her hips and a glint in her eyes, stands on the deck of a 52-foot-long ship anchored in Fell’s Point. In her tricorn hat, short leather vest, gray skort and red sport sandals she looks like a cross between Captain Jack Sparrow and the mom next door. And as she faces the crowd assembled on the deck of her double-masted, skull-and-crossbones flying vessel, the Fearless, it becomes clear that’s the point. In this zone where 19th-century American privateers (pirates for hire) harassed the British navy so much that they deemed Baltimore “that nest of pirates,” Tschantret and her co-workers have launched a latter-day swashbuckler rebellion.

Tschantret heckles a staffer, a shaggy-haired man dressed in a leather cap and ruffled shirt. “Tell them how you came by your name, Scarnose Jim,” she calls. Grinning, Scarnose (aka David Lustig), replies, “When I was a wee pirate, I tried to pick me nose with me sword. I missed.” The crowd cracks up.

Corny jokes and yo-ho-ho and a bottle of rum talk has been floating around the Inner Harbor since July, when Tschantret and her mates, er partners, Cara Joyce and Lauren Bolin started taking guests on pleasure cruises as the Urban Pirates. On one-hour trips, these latter-day, not-so-high seas adventurers commandeer the Volvo engine-powered boat around the Inner Harbor.

The trio got the idea for the buccaneer biz after Joyce’s son attended a nautical-themed birthday party in Annapolis. They thought a modern pirate ship would be an ideal fit for Baltimore, where, in Fells Point, a fair bit of swashbuckling went on during the War of 1812. “I think people simply like to act like pirates because it’s a little release for them on the weekends,” says Joyce. “Pirates can behave however they like!”

Now, Tschantret and co. lead trips geared toward both kids and adults. Tonight’s quest: a “bring your own grog” adventure for revelers 21 and up. Family-friendly trips —­which feature more games, and no bottles of rum — take place on Saturdays and Sundays during the day. There’s also a free pirate story time Fridays at 10 a.m. when the ship is docked at the Ann Street Pier.

Tonight, however, ain’t kiddie book time. Booze cruisers, who range in age from their 20s to their 50s, come aboard, bearing bottles of Captain Morgan’s rum and Miller Lite longnecks. Staffers help them into rogues regalia: colorful beaded necklaces, vests, bandannas and even an eye patch or two. “It’s funny, though; most adults come dressed already,” says Joyce. “We’ve had mermaids, Peter Pans and many Captain Jack Sparrows.”

Then, as a reggae soundtrack blares from the ship’s speakers, “The Fearless” heads into the Harbor. During the hour-long venture, staffers lead passengers in shanty sing-a-longs, name games and a hysterical group dance — shiver me timbers — to Sugar Hill Gang’sApache.” The chorus pulses as Tschantret demos moves from “swabbing the deck” (hip sashays) to “raising the flag” (fist pumps). Yeah, it’s all a tad silly, but the drinks help, and so do the bold bandannas and beads.

On children’s trips, the emphasis shifts to seafaring lore. “They learn how to talk, dance and sing like a pirate,” says Tschantret. “They also find out how to tie ropes, fight their enemies and defend treasure.”

Like any good Errol Flynn flick, tonight’s grown-up cruise builds to an action-packed climax. The Fearless approaches the Inner Harbor shoreline, where couples on dates crowd outdoor cafe tables.

But avast! As the vessel approaches this serene scene, dramatic music blasts from its speakers. The passengers, now fully indoctrinated, bellow a few “aarghs” and jockey for position behind the ship’s 10 water cannons. OK, so this isn’t Blackbeard’s ride — these blasters work like giant water guns, not real firearms. Still, the tourists on paddle boats don’t stand a chance. They get soaked but still smile and wave at the Fearless’ crew.

Mad Dog Mike,” the motorboat-driving nemesis of the Fearless (played by Urban Pirate staffer Joe Miller) doesn’t get off as easy. The villain makes a beeline for the Fearless, shaking his pistol menacingly. Still, his tiny vessel makes him a floating duck for cannon target practice, and he’s soon sopping wet. Defeated, he speeds away.

Huzzahs are heard on deck. High fives and cries of great victory resound. As the ship approaches the dock, skull and crossbones still flying, you’d swear you heard a peg leg scrape the deck and a parrot squawk.

&raquo Through Oct. 31, cruises Sat.-Sun. at 9:30 and 11 a.m.; 12:30, 2:30, 4 and 5:30 p.m.; adults only, bring-your-own-grog trips Fri. at 7:30 p.m. Board at Ann Street Pier (Ann and Thames streets); $25 adults, $20 children, $10 children under 3. Info: or 410-327-8378.

The loudest revelers win a shot of Captain Morgan.

Urban Pirates shake it up in Baltimore to Sugar Hill Gang’s “Apache.”

Photos by Lawrence Luk for Express