The Southeast Alaska Pilots Association (SEAPA) is concerned with how well one mega-cruise ship will be able to manoeuvre the state this season.

Marine pilots from the association tested the limits of four mega-ships – the Norwegian Bliss and its sister ship, Royal Caribbean’s Ovation of the Seas and Princess Cruises’ Royal Princess – that will be visiting southeast Alaska through virtual reality.

While the Ovation of the Seas will be the largest ship to ever visit Alaska, the marine pilots were far more concerned with Royal Princess.

“Overall the simulations (for the Royal Princess) produced serious challenges in the wind and current conditions common to Southeast Alaska,” the pilots wrote in a report.

Apparently, the Royal Princess doesn’t do well at low speeds especially with its standard propulsion system which uses propellers and rudders. Azipod propulsion is used in the three other ships.

Keir Moorhead, an engineer who teaches at California State University Maritime Academy explained, “With Azipod-style propulsion, the propeller is actually on a pod below the ship, and what you can do is rotate that pod.”

“At any given moment, you can rotate a propeller 360 degrees to give you thrust in any direction,” Moorhead said, indicating that it allows big ships to manoeuvre in tight spots at lower speeds.

The SEAPA suggests that Royal Princess doesn’t attempt to pass through the Tongass Narrow, which is only 220-meters-wide, at more than 15 knots of wind (though there is a 7-knot speed limit for this area). With little room to manoeuvre through this pass to get to Ketchikan port, the cruise ship could have some trouble.

In response, Princess Cruises’ vice president of fleet operations, Keith Taylor said, “While we appreciate SEAPA’s (Southeast Alaska Pilots Association) efforts to date, we believe the model they used to assess this ship requires further refinement. There are three Royal Class ships operating safely around the globe, in many challenging navigational areas.”

While it doesn’t appear that Princess Cruises is too concerned, hopefully, all goes well on Royal Princess’ first visit to southeast Alaska on May 13.