Gas turbines

I have heard a number of discussions regarding these engines and could you please tell us how often these engines are used please? The original chief engineer stated they were only ever used to top up the power requirement when a higher cruising speed is necessary, whilst others claim they are 'run up' whenever the ship enters confined waters?

When the ship has her main engines replaced, will you consider fitting larger, more powerful main engines that could propel the ship at a higher speed which might be used for transatlantic crossings?

I hope you approve of my two ships :)

Dear Glojo,

The total power that an electrically driven cruise ship or liner requires is a combination of propulsion power for any given ship speed, the hotel load for lighting, air-conditioning etc and losses within the electrical system. Its common knowledge that Queen Mary 2 was specifically designed to sail at 23 knots in reasonable weather using her four diesel engines; one or two gas turbines are brought on line for higher speeds or when one or more of the diesels are undergoing maintenance. The combination of what is used and when is dictated by the sailing speed required, the hotel load, losses and maintenance cycle. The same holds true when manoeuvring. Whatever power is deemed required is matched by putting the available engines on line, diesel engine and/or gas turbine.

The Queen Mary 2's hull form has been optimised for the power available to her. Installing more power wouldn't necessarily increase her speed as much of the power would be dissipated in creating ever larger waves at the bow and stern.

Thank you for your question. And yest the two ships look good!

Stephen