Overhaul

By Will Sellers

The bottom of the ocean is a hostile environment and it takes a toll on equipment. The enormous pressure is hard on materials and the hydrothermal vent fluids are very corrosive. Every two to three years Alvin comes home to Woods Hole for a complete overhaul of all of its systems. Six to seven months are needed to do a thorough job but only four or five are scheduled. Overhaul is always met with anticipation by the operations crew. After being at sea nine months a year for two or three years the thought of working 8 to 5 with weekends off like normal people is very appealing. It doesn’t seem to work out that way though. Every one looks forward to their first over haul but not many look forward to a second.

Overhaul is no small task. It begins with unloading the ship of everything that is Alvin; spare parts, tools and support equipment. It also means you. During overhaul they take away the place that you live on the ship. I’ve heard the old argument of “The poor dears have to pay for their own food and housing” but you have to realize that the Alvin boys are grossly underpaid and a bed and food is part of the deal. This is the first pothole on the road called overhaul.

This huge undertaking is always scheduled for the winter time as Woods Hole is a summer resort community and the men off the ship can find a cheaper place to live, or one at all for that matter, in a winter rental. And that’s about all the help your going to get from the home office. They couldn’t care less if you lived in the street as long as you showed up for work on time. Within a few days you have to be off the ship with all your belongings. A winter rental can be one quarter of the summer price but will still set you back $1000 a month or more. And with all the utilities that go with a New England winter there is no way you can swing it alone on what they pay. Ironic as it seems you wind up sharing a house with two or three of the same guys you spent the last three years at sea with. Being mostly young testosterone charged guys, it leads to a hard-partying, dorm-like atmosphere.

Located on the WHOI dock is the Islin High Bay. This building was built just for Alvin overhauls although it serves many other purposes when Alvin is at sea. Roughly 50 X 100 feet it has a 40 ft. high ceiling with a 25 ton over head crane. A facility like this a necessary to service the submersible. The batteries are removed while the sub is still on the ship due to the infrastructure involved in that. Alvin is then placed on blocks in the middle of the high bay work benches with shelves and cabinets are assembled around the perimeter of the work space for parts and tools. A couple of 20 ft. shipping containers will serve as the electronics shop and an office to deal with the paperwork. And there is a fair amount of that. As Alvin is certified by the U.S. Navy they demand the paper trail that only a bureaucracy like that can generate.

Once a proper shop is set up the dismantling can begin. There isn’t a single piece of the sub that comes off that doesn’t get a complete going over, from the skins getting painted to all the welds in the sphere being tested by ultra sound. Very quickly the sub gets stripped down to its basic components leaving the bare frame in the middle of the room. Off to one side, the sphere sits in its stand and the carpenters build scaffolding around it so the electrical types can get in and out to do their work. The frame, being made of titanium, sees a tremendous amount of strain being lifted out of the water every day. It gets sent to a specialty welding shop in New Jersey to have all of its welds x-rayed looking for cracks to be repaired. The frame could be gone for a couple of months but that’s OK. It’s not needed right away but you do need the space it takes up in the high bay.

Meanwhile work begins on all the individual pieces and sub systems. The list is pretty long. Some items are simple but most are fairly complex. The manipulators are stripped and rebuilt as well as the hydraulic system that powers them. Great emphasis is put on all the safety systems and their redundant backups. Alvin’s sphere has 23 penetrations that go through the hull for electrical and video connections. Many of these penetrators, as many as half, will be replaced and sent to the company that made them for rebuilding. Each one has 24 wires so this means extensive rewiring inside the sphere and outside on the body of the sub.

After being there a couple of weeks the high bay is organized chaos. Ninety percent of the work being done is accomplished by the pilots or the technicians training to become pilots. The work breaks down into three groups; the mechanical section that will care for the hydraulic parts, the variable ballast system, manipulators and the mercury trim system just to name a few. The electrical team will see to all the external wiring, the batteries, explosive bolts and cutters as well as the refitting of all the junction boxes. The electronics team will take care of the inside of the sphere as well as all the cameras, strobes and all the electronics of the surface control station.

A couple of months into the overhaul you get settled into a routine of working 8 or 9 hours a day and having every weekend off. This is a real treat! Quite a different life from being at sea. Too bad it’s not going to last. The honeymoon is over once the frame comes back. For the last 2 or 3 months the work has all been on the individual parts and now that the frame has returned the assembly of the sub can begin. It’s also this time that everyone, particularly the management, realizes that overhaul is more than half over and it’s time to kick it into high gear. The first casualty of this are those weekends off and you find yourself working 7 days a week just to go to sea. It takes 7 months to do a complete overhaul but you get 5. They don’t tell you this up front and that’s why no one looks forward to a second overhaul.

The pace becomes grueling at 12 hour days 6 to 7 days a week. The pressure becomes huge to get the job done in time including threats of any one holding up the completion date loosing their job. I have done 3 overhauls and not one of them was planned well. Each time there is not a long enough period scheduled but management counts on the ops guys giving up any semblance of a life to work 90 hours a week just to go back to sea. Once we got away from the dock and out to sea we still worked the same long hours but without complaint as we were doing it for ourselves and not for the “office scum”.

The loser after every Alvin overhaul is science. They all end the same. As the sailing date draws near all the effort is put on getting the basic sub working so that on the first dives it will go to the bottom and back with all systems related to safety operational as the Navy certification must be satisfied. What science has to put up with is the first 2 or 3 months with no data logger, no strobe triggers for the hand held cameras and dozens of other small but important items that were pushed aside with no priority against getting that Navy certification. They will all get fixed at night after a full dive day by the same 5 or 6 pilots and techs that operate the sub by day.

The one shining star of doing an Alvin overhaul is working with the men of the WHOI shops. On the dock and all around the high bay are the welding, mechanical, electrical and machine shops. Their main function is to support Woods Hole’s ships and all the scientific projects that come up. Of the 1000 people that work at WHOI about half are dedicated to engineering rather than biology or geology. They are closely entwined building the tools, traps, sensors and vehicles that oceanographers need to do their science.