Current position of the SSV Robert C. Seamans. Click on the vessel to view position history. Use the tools, top right, to change the map style or view data layers. Dates and times use GMT (Greenwich Mean Time).
SEA Currents: SSV Robert C. Seamans
August 03, 2018
Reflections from the engine room
04 degrees 41.360’ S x 174 degrees 37.574’W – Drifting off the Island of Nikumororo
Sunny skies, with poufy cumulus clouds on the horizon (just enough to have a good sunset)
While on board this ship, there have been endless seemingly everyday occurrences that are different and wild and wonderful, a new form of spectacular around every corner. One of these more hidden corners acts as the heart of our vessel, a hummingbird feverishly working, beating its wings in the great throat of the ship. My younger brother, Liam, is a mechanic, and immediately upon descending the ladder into the first of a series of rooms that keep our ship – the Robert C. Seamans – afloat, I was reminded of him. What a playground this could be for him! So many different machines, and on a scale so magnificent and consuming. You crawl into the engine space, and you are a machine ticking and thrumming alongside the engine, flesh and bone humming alongside ferrous metal in the sweltering heat. The massive, 500 Horsepower V8 Caterpillar engine holds a chest-space, a footprint, large enough to swallow me whole. (It’s larger than my bunk! Maybe even more comfortable, too.)
At any given time, at least two of the eight cylinders are exploding with controlled combustions, as the other six cylinders each fulfill one of the other four strokes involved with harnessing the pressure associated with the rapid expansion of the explosion. (Waste heat from the jacket water that threads through cavities and passageways inside the engine can also be harnessed to use as radiative heat to warm the boat in cold weather, like off of the primordial fern-treed coasts of New Zealand, or to warm the water we use for our showers.) Three other steps aside from the explosion occur in a near-infinite loop, as the engine runs itself until it can no longer function (whether through lack of fuel or by overheating from its labors). First, the piston falls, acting as a pump to draw in air through valves, which close when the piston compresses the air to pressures that generate remarkable heat, up to 1000 degrees F. Once the air is compressed, the chamber is injected with a misting so fine that the diesel fuel is atomized, exploding upon contact in the super-heated environment. The finer the mist, the more complete and total the combustion – the more efficient the burning of fuel. The chamber is left full of residual exhaust that will not combust, CO2 and water vapor, which must be exhaled from the space in order to pull in a breath of fresh air and start the cycle anew.
Because there are eight pistons, two of each exist in each step at any given time, though changing rapidly, in a form of controlled and explosive wildness. Paired, almost as if dancing in lockstep, the synchronous timing of the engine is assured by the timing gears. This arrangement of bends, rounds, and rods allows for the translation of vertical motion into rotational motion, which is dampened by the flywheel – a weight with sole ownership over the job of smoothing out the rapid dancing and leaping of the pistons, making sure the rotation continues smoothly in the proper (or rather, the same) direction – and travels through reduction gear to reach the propeller of the boat, sending it spinning. The reduction gear ensures that the propeller does not rotate with the same force and/or gusto as do the cylinders of the engine; if the propeller spun at 1400 RPM (rotations per minute), it might fly off into the water, never to be seen again. It might boil the wake and melt the boat, or melt itself, or both. In truth, the cavitation created behind the gently sloping bevels of the propeller would cause such incredible temperatures that a hole would be very quickly worn in the back of the boat and outside would be all over inside. (Like a zebra mantis shrimp’s super-fast strikes!! The cavitation is tiny vacuums building due to sheer speed and force of movement, which then explode with tremendous heat. Only here, much larger, and, a boat, rather than a tiny and truly ridiculous crustacean.)
There are three other diesel engines onboard, each associated with a generator that they power. Only, the rotational motion produced by these diesel engines is used to turn electromagnets past coils of wire to provoke the movement of electrons in that wire, tumbling one after the other into an electrical current. These electromagnets are also wires; if you were to pry open one of these generators, the mess of coils that would spring out would be at least double than what you were expecting upon hearing “electromagnets turning past coils.” These coils (six in each of the two larger, non-backup generators) create a sinusoidal wave of energy that move in three phases, one after the other, creating a maximum coverage of “southern” troughs and “northern” peaks across the zero axis by which they must pass to experience both states of absoluteness. There are 60 cycles of each wave passing zero per second; these are measured in Hertz. This produces the electricity that powers our lives on this ship, creating all the comforts of a small municipality on board a 40-meter vessel in the middle of the Pacific Ocean (well, all comforts sparing a post office, I suppose).
Many wonders, both small and large, are animated by the current induced by these generators. All of the systems that allow us to live comfortably on this ship are powered by electricity (this ship, our tiny cork, surrounded on all sides by the Vast Blue of All Blues, kept afloat by a pulsing electric heartbeat: can you see it?). Because of these diesel engines, we can move forward in the seas, we can turn on lights to read by, we have fans to cut the oppressively humid heat, and we have a fully operational sanitation system, like a small city. We have a refrigeration system that allows us to have fresh fruits and vegetables in the middle of the South Pacific; just the other day, we had beautiful, dripping gold and red mangoes with breakfast. We have delicate strawberries, thousands of miles from the fields in which they were grown. This means! Nobody’s gotten scurvy (yet – keep your fingers crossed). We constantly have fresh water to drink and wash our clothes in, and to rinse ourselves clean of the salty mixture of intermingled seawater and sweat at the end of a long day. The water makers operate based on reverse osmosis, in which a massive amount of backpressure is applied to seawater running past a semi-permeable membrane. That water is either forced through the membrane – which can only allow water to pass, as the ions and salts are too large – or leaves through an incredibly tiny valve. The water that sheds its salts in favor of crossing the membrane becomes fresh water, while the water that opts for the valve leaves back into the sea as super-saline brine, carrying with it the excess salts and minerals that could not pass the membrane.
Our ship is a microcosm in innumerable ways, not the least of which is the fact that our every creature comforts gets attended to by the equipment that can be packed into the belly of a 40-meter brigantine. The intimate closeness of these machines narrows the gap we have all been raised accustomed to, it cuts down the Distancing of Use we operate within during the majority of our lives. Here, the illusion of endless fresh water supply, of instant and invisible wastewater treatment, the act of “throwing things away” (aka, the re-arrangement of dirt on a finite boat, on a finite planet) is dashed. In massive cities, these are not processes we get to see occur, and we are not given the numbers to start and finish with in the way we are here. This ship begs its inhabitants for conscious consumption, and we have shipmates reminding us of this every day – the engineers care after these machines and our use of them, giving us our numbers and showing us plainly our communal depletion of shared resources. These things are, in a way, luxuries; they make thoughtful, conservation-minded use possible in ways that I have never seen or experienced before. On board this ship, all we need exists around us because of millions upon millions of contained explosions, pumping harder and faster whenever we ask them to. In having our whole world in a drop – a drop that, without the vast ocean around it, would be lost and parched – I have come to understand how truly finite a planet we live on. On, in, with. Together.
- Chloé-Rose Colombero, A Watch, Harvard University
I want to make a couple shout-outs here – to my family; my mom, grandmother, and brother. I am thinking of you always! Every wishing star I see, I think of you, of your health and happiness.
Liam, I apologize for what an amateur job I’ve done in capturing the magic of the engine rooms, I know you would be able to much better read this space than I would ever be able to, and I wish you could see it! I will ask lots more questions, and take pictures, and have more for you when I come home. Love you lots.
To the radiant humans I get to call my friends, and to my co-op (past, present, & future!) – I cannot wait to see you again, to break bread and swap stories. In the meantime, please view this picture of some giant clams and just *know* in your heart of hearts that I’ve peaked.
An internal shout-out to the engineers on board, Nate and Henry, who gave me an incredible amount of their time (and patience) in explaining our mechanical shipmates to me. In this vein, I would like also to give a shout-out to the Fixers of the world: thank you for fixing things.
And here, I arrive back to my mom. Moma, if this starts with you, it also ends with you: if it weren’t for your support and your sacrifices, I would not only not be here, but I wouldn’t be anywhere. I miss you dearly, and I am sending loving thoughts from the blue.