How Incat Crowther fit more ferry into 48 m

Grey Lady IV

SEPTEMBER 20, 2016 — Design Incat Crowther says that it faced some design challenges in meeting the capacity requirements for Grey Lady IV, the 493 passenger catamaran passenger ferry recently delivered to Hy-Line Cruises by Gladding-Hearn Shipbuilding, the Duclos Corporation (see earlier story).

The new vessel, commissioned in response to increased ridership, is an evolutionary step from the three previous Incat Crowther vessels delivered to Hy-Line by Gladding Hearn.

The 48 m LOA x 10.5 m beam catamaran is the largest in the fleet with additional passenger capacity, an increased luggage space and a VIP lounge.

The capacity increase had to fit in with docking constraints, which enforced upper limits on both the length and beam of the vessel.

In the face of these challenges, Incat Crowther’s solution included moving the wheelhouse to a third deck, freeing up the front end of the second deck for VIP passengers.

Balancing the extra deck’s weight with increased capacity and passenger space amenities of the passenger spaces, Incat Crowther was able to propose a design that met performance and revenue requirements.

The VIP cabin has a superb forward facing view and is the only such cabin on a fast ferry serving the route.

With the increased passenger capacity and the addition of a VIP service class, special attention was given to boarding arrangements and passenger flow.

A mid deck boarding door was added and both forward and aft. Stair towers arranged in an efficient manner improve passenger flow and improve turnaround times.

Passengers who board over the bow are served by a stair tower from the main deck cabin, via the mid deck to the outdoor roof deck.

The arrangement not only improves passenger flow, it adds a further dimension to Hyline’s passenger and luggage movements by giving VIP passengers a dedicated access as well.

Designed to perform at a service speed of 30 knots, Grey Lady IV is powered by a quartet of Cummins QSK60-M main engines. With a rating of 1,641 kW each, they were selected to be run at a modest engine speeds in day to day running, with reduced wear and tear and increased time between overhauls.

The rating allows the vessel to maintain its service schedule on three engines.