Navigating Regal Princess through the Narrows a special skill

The largest cruise ship ever to visit St. John's harbour departed Tuesday, but not without the skills of local marine pilots.

Paul Kean took the helm to safely navigate the Regal Princess, which hosts nearly 5,000 passengers and crew members, through the Narrows, along with Lou Power who monitored the ship's progress and other marine traffic.

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The Narrows, as its name suggests, is essentially a narrow notch between the rocks entering the harbour in St. John's, and Kean said that's the kind of challenging situations he specializes in.

We knew it was going to be right on the edge of a job that was either going to be safeor not safe.- Paul Kean

"It is a big ship, 330 metres long and 38 metres wide and trying to fit it into a 75-80 metre wide channel, you've got to hit it right dead centre, so yeah there's a fair bit of judgment in everything with it," Kean told CBC's St. John's Morning Show.

He added there's "absolutely zero" room for error when piloting a ship that size through the Narrows.

"When you're outside and you start heading towards a small notch in the rocks, it is what it is. You've got to hit it right, you've got to hit the middle of the notch and you have to allow for a bit of surface current," said Kean.

According to Kean, marine pilots have specialized knowledge about navigation and water conditions in their local area, and are brought in to steer ships safely through to harbour.

Depending on the size of the vessel, Kean said there are some regulations that require a marine pilot to navigate a ship in or out of port.

Kean has been a marine pilot for 16 years. Hesaid whileTuesday's task was essentially another day on the job,piloting the Regal Princess was a "special job" that required special preparation.

"We spent the last year preparing for its arrival, we knew last year that the ship was coming and we knew it was going to be right on the edge of a job that was either going to be safe or not safe," he said.

Kean and Power spent about a year preparing to pilot theship, including a computer-simulated navigation of a ship that size.

"We were blessed with a great day for the arrival and departure and everything went according to plan," said Kean.