While I was in Pensacola for preflight and basic flight school Pat and I had purchased a mobile home. It was a single unit twelve feet wide by 70 feet long. Sometimes naivete can be handy. Since it said mobile home we figured it would move. We moved it from Florida to Mississippi with very little damage. When I left flight school we just figured we would move it to Massachusetts. Luckily I had earned 30 days leave. It took them almost a month to get it there. The number of tires they went through was hard to believe. But they made it with very little damage. The navy even paid to have the trailer set up on the lot in a trailer park on the Air Force Base on Cape Cod near my parent’s home. It would be a long commute to Newport but I would be home and when I got out of the Navy I would go work for my father.

I was going to be the MPA (Main Propulsion Assistant). This meant that I would be in charge of all propulsion equipment on the ship. I would be one of three officers in the engineering department. The Engineering Officer would be the department head, I would be one division officer, and the Repair Officer would be the other division officer. The repair officer is responsible for damage control and the maintenance and repair of all machinery not associated with ships movement.

I was sent to the Main Propulsion Engineer school at the Destroyer School in Newport. There a class of about 20 prospective MPAs would have the secrets of ship propulsion revealed to them in a few short weeks. The course was aimed at destroyer/destroyer escort propulsion plants. The main difference between the two classes of ships, from the MPA point of view, was that a Destroyer would have two propellers to the Escort’s one. Each propeller would have it’s own engine room and pair of boilers in their own.

We learned both in the classroom and in a training area that had actual examples of different pieces of equipment. The lab had the pieces of equipment spread out and, in some cases, cut away to permit close up inspection. Another advantage of the lab was that all of the equipment was spread out enough so that you could learn the piece of equipment without the confusion of additional machinery getting in your way. In the classroom we would put the equipment together and get a feel for how crowded and how much overlap there would be on our ships.

The propeller is driven by a propeller shaft which caries the force from inside the ship to outside. In order to transfer some 35-40 thousand horsepower from the engine to the propeller the shaft is over a foot in diameter. Where the propeller shaft penetrates the hull is a seal to permit the shaft to rotate freely while keeping the ocean out. These seals must be repaired from time to time so there is an additional inflatable seal that can be used to keep the water out while the normal seals are replaced. The inflatable seal can only be used when the shaft is stopped.

There can be several lengths of shafting between the propeller and its driving engine. In the case of a destroyer, in fact one shaft will be longer than the other because one engine is in front of the other. These shafts consist of segments that we learn how to bolt together and take apart. Each shaft must be supported every once in a while with a bearing. These large journal bearings must be properly lubricated and periodically must have their working surfaces replaced in order to provide support without causing undue restriction on the rotation of the shaft. We learn about controlling the oil temperature and how to replace the bearing surfaces.

Next up the line is the thrust bearing. The thrust bearing is what transfers the force of the propeller to the structure of the ship. The next big item is the reduction gears that take the energy from the high-speed steam turbine and slow it down to the usable speed of the propeller shaft. This is an awesome piece of equipment with a main (or bull) gear over 10 feet in diameter. Next are the steam turbines. The high-pressure turbine is smaller, it takes the steam directly from the boilers and exhausts into the low-pressure turbine that exhausts into a seawater cooled condenser to extract as much energy as possible from the steam.

The boilers, usually two per engine are in a separate compartment (or room). They are large structures that take two or more decks. In MPA school we learn of the two major types of boilers M and D. They are called this because the layout of the tubes which carry the water are laid out in the general shape of the letter. The examples in the lab had large area’s cut away to show us the internal structures. Normally the firebox, (the place where combustion takes place), the refractory (Fire-resistant brick and masonry), the steam tubes and other internal parts are normally enclosed in a case which is surrounded by an air plenum which is used to preheat the incoming air before it is mixed with the fuel for combustion. All of this is warped in insulation.

The air is sucked into the boiler through an outer layer of the smokestack by large fans called Forced Draft Blowers. These are big variable speed fans that draw the air in and then force it into the air plenum where it is mixed with fuel and atomized in burner nozzles. .

The firing rate (the energy produced in a unit of time) is controlled by three primary variables. The Amount of air, fuel, and water that are moved in any time unit. The number and type of atomizer plates on burners is increased or decreased manually. If the number of burners is increased or the nozzles are changed to increase the amount of fuel going into the boiler the quantity of air being feed into the boiler must be increased to properly burn the fuel. As combustion increases steam is generated faster and more steam flows out of the boiler it must be replaced by water coming into the boiler. In theory a simple task, in practice a delicate balancing job for the engineering people on watch. If any one of the factors gets too much out of balance there will be damage. The damage can vary from soot building up on parts of the boiler to overheating of the metal elements of the boiler. Soot acts as an insulator and overheating can cause metal to fail.

In addition to these main elements of the propulsion system there are many pieces of support equipment from water, fuel, and lubricating oil pumps, a system for removing air from the water, electric generators, up to evaporators to make usable water out of sea water.

The evaporators use steam to boil seawater and collect the evaporated water that is used for make-up water for the boilers. Normally this is a relatively small amount of water since the water that is changed to steam in the boilers. It flows into the main engine turbines to drive the ship then flows into a condenser beneath the low-pressure turbine. There the remaining steam is cooled by seawater back to a liquid state so it can start the cycle over again. In this closed system the only water that needs to be added is due to loss as leakage. Ideally, this would be zero, in real life it can vary wildly.

The vast majority of the output of the evaporators is put in potable water tanks and is used as fresh water for use throughout the ship. If the evaporators have production problems or the propulsion plant has excessive demand, however, the crew has a lower priority on water usage than the plant does.

This was a very good school and gave me a feeling for how all the pieces come together to make a ship move through the water. It showed me the big picture and gave me an idea of what maintenance needed to be done in order to keep the ship operational. It also gave me a feel for what to look out for to anticipate problems. It did not, however, give me the skill or ability to fix or maintain anything. That is what the people who were assigned to my division on the ship were there for. Now I had the tools to understand what my men were telling me and enough knowledge to talk to them about what needed to be done.

There is one slight difference between the propulsion plant I had studied and that on the ship I was going to. The boilers were radically different from the M and D style boilers. Fortunately, there was time for me to go to another school. The school was designed to teach the enlisted men on this type of ship how to maintain and operate this new type of boiler.

I reported to Boilerman B school in Philadelphia, Pennsylvania for a course in Supercharged Steam Generator Operation and Maintenance. The Supercharged Steam Generator was supposed to be a smaller, cheaper way to make the steam to move a ship. It produced superheated steam at high pressure burning JP-4 fuel (the same fuel used by all NATO jet planes) instead of the black oil used by other steam ships.

Instead of forced draft blowers this system used a turbine to compress large volumes of air to be mixed with fuel to heat the water then the hot gasses of combustion would exit through the other half of the turbine to drive the compressor before exiting through the smoke stack.

The Compressor side of the Supercharger draws the air in from the stack, compresses the air (which heats it) and provides it to the burners so that the ratio of air to fuel is 17 pounds of air for each pound of fuel.

Instead of having burners with different nozzles put into use to control the amount of combustion there were three triplex burners in each boiler. Each burner was supplied with a constant flow of fuel. The amount of fuel that went into the furnace would be controlled by how much fuel was allowed to flow out of the burner and back into the fuel system.

The burners would be mounted on the top of the boiler instead of the side so the only refractory (fire resistant materiel) would be on the floor of the furnace. Because of the size and shape of this new boiler the weight would be significantly reduced by going to a top-fired configuration.

The tubing that the steam is created in would be arranged in a circle with the upper portion of the tubes sealed against one another. Towards the bottom they would spread out and be arranged to provide a gas path radial out across a set of superheater tubes. The gas would then pass upward and through the turbine sector of the supercharger.

As most of you know the temperature of steam is 212 degrees Fahrenheit. If, however, you can remove the steam from contact with liquid water you can add more heat to it. More heat equals more energy so we took the steam through dryers which separate any drops of liquid water that might be carried with it. This "dry" steam was then sent through separate steam tubes that circled the lower part of the boiler in the path of the hot gas flow. By keeping the pressure high (1200 pounds per square inch) and heating the dried steam we were able to transfer maximum energy from the fuel to the steam. Steam can easily be moved from place to place through pipes

Another unique factor with this system was an Automatic Combustion Control (ACC). Since the boiler was top fired, used the same burners from startup to full power, used an exhaust driven compressed air supply and was small in size changes to air, fuel, and water supplies needed to be more closely monitored than could be done by humans.

This school was quite different from the MPA School. Here I learned the details that I wouldn’t normally learn as an officer, details that I would never be called upon to use, but I am thankful that I had the opportunity to learn what my men had to know. It allowed me to communicate on a different level with some of my men, unfortunately, it was a luxury that most officers never have the chance to experience.

I finally joined my first ship after having been commissioned for almost two years.