Monday, April 11, 2011

Entry 30 4.5.11

Entry 30, April 5th, 2011, 10:13pm (ship time)

The ocean in inexpressibly vast.

Last night we left Cartagena and started the crossing North to Montego Bay (Jamaica). This leg of the voyage is known for being rocky, but last night was particularly bad. There were 8 foot rollers (this measurement is totally arbitrary, I have no idea how to measure the size of waves other than pure guesswork) coming in from the East and pummeling the Starboard side of the ship all night long. I'm pretty sure the captain was using the stabilizers, because the roll of the ship was not too bad, but pitching from bow to stern got fairly interesting. There is one spot all the way forward in stair 12 that moves up and down about 10 feet with each wave in that kind of weather.

Sometime after midnight, I undogged one of the hatches on Deck 5 forward and went out to take a look. Despite the shelter of the promenade deck, the wind was tearing at my clothing and I felt the need to hold on to my glasses. I took a peek out of one of the open portholes just in time to get a face full of spray – this is on deck five, the equivalent of getting hit with spray standing on the roof of a four story building! I'm proud to say my stomach didn't give me any trouble – it has been resolutely iron-plated for the past four and half weeks. No seasickness for this guy.

The sobering thought here is that this was nothing compared to what the ocean is really capable of. This was the equivalent of a man rolling over in his sleep, maybe muttering some nonsense words before returning to peaceful slumber. I am excited and yet a little frightened to see what a real storm is like. Nothing like a few waves to make a 70,000 ton ship feel small.

Part of the pitching was probably due to the design of the Lady G's hull. I had fifteen minutes to burn up in one of the conference rooms last week and used them to take a long look at a model of the ship mounted on board. I surprised by what I found – while above water the ship looks like a floating brick, below it resembles a very large speedboat. Along the centreline the ship draws a uniform maximum (10 meters or so) from bulbous prow to stern thruster, but the lines are radically different just a few meters on either side of the keel. As one descends from the main deck, the hull tapers rapidly inwards. It doesn't reach full depth at the beam ends until perhaps halfway back along the vessel! This is where the stabilizers, diesel engines, generators, electric motors, and prop shafts are – all the heavy stuff is put there to keep the Lady G stable (tanks of heavy fuel oil and such are also located along the keel, adding to the stabilizing force). I'm no naval architect, but it looks like this design follows some of the same principles of speedboats that hydroplane across the water, generating some lift as the ship moves forward. Of course, with a ship this size, the effect would be far less pronounced than with a speedboat, but it would help with fuel economy somewhat (less hull in the water = less friction). Compare this with a liner like the Titanic, where the hull was a square “U” shape almost from bow to stern.

I think this also means that waves can get “under” the Lady G more easily. With mass and displacement of the vessel concentrated in the middle-aft section of the ship, the bow can be more easily pitched up and down as it cuts through the waves (the heavy machinery acting as a pivot). Please, if someone more knowledgeable about physics is reading this blog, feel free to correct me.

Got some good practice in today. Orchestra had the day off, and so I got about three hours in. I spent the last hour on a Clifford Brown transcription (“Donna Lee” from The Beginning and the End), and got another 16 bars done. At this point I was pretty mentally and physically tired and decided to call it quits – yesterday I played about five and half hours and so I don't want to push it with two shows tomorrow.

Tonight promises to be crazy on the back deck – in case you aren't following professional cricket (and I mean, come on, get with the program!), India just won the World Cup, beating both Pakistan (a tense match) and Sri Lanka. The Indian members of the crew stayed up from 4am until 10am (ship time) watching the game, and tonight is the celebratory party. I look forward to scoring some delicious Indian food.

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