When you first arrive on a submarine, you are pretty much useless - and your shipmates let you know about that right away. When you first come aboard, you will be called a "NUB". This is Navy slang for "Non-Useful Body".
A submariner who is not qualified to stand watch will frequently be called a "Nub non-qual, air-wasting, space-wasting, water-wasting, rack-wasting useless piece of sh*t". More or less profanity might complete the description, but you get the general drift.
If only to avoid the indignity of being called a NUB and being sworn at, the goal of a newly-reported sailor should be to get qualified as quickly as possible. This is not an easy prospect though; In school you only had to learn and qualify on a training reactor, but now you are aboard a ship. Qualifying on an actual ocean-going ship requires understanding a great deal of equipment that was never taught at school.
For example, you have to learn to operate the ship's drain system so that you can pump bilges. You learn how to operate the ship's Emergency Propulsion Motor (EPM) and Secondary Propulsion Motor (SPM). You learn how to be a reactor compartment control point watch, and how to care for the ship's main storage battery. None of these things were part of the curriculum at the training reactor. A typical nuclear propulsion submariner would require a couple of years to become fully qualified, and another year to become truly proficient at all his watch-stations. Tack on two years prior training and you can understand the six-year enlistment contract.
One of the first things you qualify for is PVO, or Primary Valve Operator. The primary valves are those valves that contain radioactive primary coolant. As an electrician, PVO was not a task I had to perform as a matter of routine, but every nuke has to know how to properly operate and care for these valves. In an emergency, any nuke may need to use the primary coolant valves, so it's vital that everyone know how to properly operate them. In addition to being critical equipment, primary valves are expensive and difficult to replace - so you don't want to damage them through lack of training.
Another newbie qualification is phone talker. In this role you relay messages - typically from an officer in charge of a scene to a different part of the ship. This doesn't sound terribly difficult, but it actually takes quite a bit of time and focus to learn proper 3-way communication techniques. It's particularly challenging when repeating long technical phrases over the phone, and then ensuring that the receiving party understood and repeats it back correctly.
To understand the next bit, you need to understand where the action takes place. Have a look at the cutaway below.
The reactor compartment is not normally open, nor accessible. However there is a shielded space just above the reactor called the tunnel, which allows personnel to move between the forward and aft sections of the ship. The aft end of the ship is divided into four spaces: The forward propulsion spaces are called Machinery Space Upper and Lower levels, and the aft spaces are the Engine Room Upper and Lower Levels.
Below: A view of the forward reactor tunnel door, looking toward the front of the ship. A primary valve (with a stainless steel water-tight cover in place) is at the bottom right of the photo. About 10 feet beneath the floor would be the reactor.
Each space in the propulsion plant has a purpose, and everything that you would find in a land-based electrical generating station is packed very tightly inside - and then some. In addition to the generating station equipment, there is the equipment that a submarine needs: Main engines, huge reduction gears, HVAC units, hydraulic pumps, the maneuvering room, carbon dioxide scrubbers, 400 Hz generator sets, desalination units, and a small bathroom. Really the entire thing was a magnificent piece of engineering that fit together like a fine mechanical watch.
The first actual watch-standing position that a nub electrician learns is AEA, or Auxiliary Electrician Aft. There is also an AEF (Auxiliary Electrician Forward), but that watch is at the front of the ship, and does not involve propulsion.
The AEA is one of three underway roving watches in the propulsion plant. The other two roving watches are supervisory: Engine Room Supervisor - a seasoned Machinist's Mate - and the Engineering Watch Supervisor. The Engineering Watch Supervisor (EWS) would be a senior and seasoned enlisted nuke, and that person could be any rate: Machinist, Electrician, or Electronics Tech.
The AEA, being the most novice roving watch-stander, gets coffee for watch-standers who are stuck in each of the spaces - Aux engine room upper and lower levels, and Machinery space upper and lower levels. Those guys are stuck where they are until relieved by someone else who is qualified, or until the ship is berthed with the reactor shut down.
The AEA has a couple of critical functions though, particularly during casualties. The AEA has to be able to proficiently operate the drain pump, and he has to be able to operate the Emergency Propulsion Motor.
The drain pump can be aligned to take suction from the bottom of any compartment in the ship, and pump that water overboard. This pumping is done routinely once or twice during a watch, but more critically, it has to be done in the event of flooding. Shedding weight during a flooding casualty is vital for the ship's survival, so the lowly bilge pumping guy has an important job at that point.
The drain pump is so important that it's powered by DC current, right off one of the battery buses. It's a very high-pressure multi-stage pump, able to pump water overboard, all the way down to test depth. Our drain pump was kind of finicky, and it had a tendency to lose suction and stop pumping. There were several tricks you had to learn to help the drain pump begin moving water. Once it started, it would usually continue to pump. But you only had a couple of clues to figure out how well it was doing. There was a tachometer and ammeter at the control panel for the motor, and a cluster of valves that would allow you to choose which compartment to suck water from. Guys in other compartments would contact you and let you know when they were done pumping their particular bilge.
Another critical qualification for AEA was learning to operate the EPM, or Emergency Propulsion Motor. There are a number of things that can cripple the drive-train of a submarine - same as an automobile. However a submarine has quite a bit more complexity than an automobile, so there's quite a bit that can go wrong. Even though a submarine has many redundant systems, there are items that could fail, and at that point propulsion would have to rely on the EPM.
The EPM is a DC motor with the armature wound on the main shaft. The main engines can be disengaged from the shaft, and then the EPM can be placed in operation. We practiced this quite a bit. The drill team might simulate a hot bearing on a main engine. This would require stopping the shaft and disengaging the main engines. Then the AEA would propel the ship forward with the EPM. The EPM wouldn't provide the ship with very much speed, but at least you would get forward motion on the ship. Forward motion is what allows submarines to have adequate depth control. Depth control on a sub is partly a matter of buoyancy, and partly a matter of water moving over the dive planes.
During casualty drills, the (roving) AEA would have to respond to every casualty in any part of the propulsion plant. It quickly made you adept at learning whether you would be needed on a fire hose, relaying messages on the phones, putting on anti-contamination clothing, or throwing open a breaker to de-energize a simulated electrical fault. You became adept at handling yourself during drills, about half of which involved donning air breathing apparatus.
It takes 6-10 months to qualify AEA, and after a few more months, you are quite proficient at it. No big deal.
At the same time you were learning how to stand watch and handle yourself for a wide variety of possible malfunctions (engineering drills), you worked alongside more seasoned electricians maintaining and repairing the ship's equipment.
Below: A simplified submarine propulsion diagram that I found on the internet.
The equipment that I had to operate, maintain, and repair were the turbo generators, motor generators, battery, EPM, 400 cycle generators (not shown), diesel generator (not shown), and a whole slew of auxiliary motors and controllers for most of the pumps, HVAC, and ventilation fans on the ship. It was a pretty steep learning curve, but it was also an interesting challenge.
The next watch-station that an electrician learns is the throttles. I always found it odd that an electrician would be placed in charge of the ship's throttles, but that's how it's set up in the submarine service. Throttleman is sometimes a very cool watch, but it is mostly pretty boring.
Below is a photo of the maneuvering room on a nuclear submarine. The maneuvering room is a small control room for the propulsion plant of the ship. The guy closest to the camera is the throttleman. The center guy is the reactor operator, and the furthest away is the electrical operator. Yes, you had to know what every gauge and switch did, how each circuit worked, and where it was powered from.
The throttleman has an important job, and that is to promptly adjust the speed of the ship when ordered. This is important when maneuvering in and out of a harbor or around other ships, and it's absolutely critical during casualties. If you mess up on throttles, you could cause a collision - or worse. The throttleman is also frequently the phone talker during casualty drills, and also during routine evolutions underway.
There's another way the throttleman can mess up, and that's by demanding too much power from the reactor. On a pressurized water reactor, reactor power follows steam flow. You open the throttles, and steam flows to the main engines. This reduces the pressure and temperature in the steam system.
This drop in temperature is transferred to the primary coolant, and the water returning to the reactor is cooler. This cooler water is now a more effective moderator, and thus reactor power starts climbing. The faster you open the throttles, the more rapidly reactor power increases.
The throttles are able to pass enough steam that you can cause the reactor to produce greater than 100% power. If you are above 100% reactor power, you are exceeding the allowable thermal limits, and the protective circuits will trigger a reactor scram. When the captain wants 100% power, he wants the ship going as fast as it can. He doesn't want to be dead in the water with a shut down reactor, so it's important to operate the throttles correctly.
Below: The SPCP (Steam Plant Control Panel), where the throttleman stands watch. Picture is from the internet. The large wheel controls the ahead throttles, and the small wheel controls the astern throttles. The propulsion turbines are able to turn in either direction.
When you get the order for Ahead Flank, that means you need to provide 100% steam flow right now. You grab the large chrome throttle wheel and whip it open hand over hand, as fast as you can. And for a few moments, this is incredibly cool. The propulsion turbines wind up with a turbo-like howl - they sound like a huge pair of synchronized jet engines. The entire ship begins shuddering and rumbling as the screw cavitates and water flow increases around the hull. And you are the one who set all this in motion. It's an incredible feeling sending 9,000,000 lbs of steel plowing through the ocean depths with your own hands.
A lot of other watch-standers get moving at the same time. The reactor operator will need to shift the primary coolant pumps to fast speed. Out in the engine room, the main seawater pumps will need to be shifted to high speed as well. The electrical operator will need to adjust the speed on the turbine generators, due to the additional electrical load, and then monitor bearing temperatures in the propulsion system.
You can't really enjoy the moment for very long though. You need to stay focused on the level gauges, the shaft RPM, the main engine pressures, and main condenser vacuum. More importantly though, you have to consider the reactor.
By the simple act of whipping open the throttles, you are pushing the reactor right up to 100% power as fast as the system allows. The trouble with that is that the reactor will overshoot. There is also quite a bit of thermal lag in the system, so something you did 30 seconds ago is still causing reactor power to climb right now.
After you open the throttles to 100% steam flow and get things going, you have to back off again, so that the reactor doesn't overshoot and scram. It's a matter of timing and the amount of throttle reduction that separates a new throttleman from a seasoned one. Operating the throttles is something you get a feel for after a while, and eventually you get it just right. After the reactor power hits 100% and starts tapering off slightly, then you can re-open the throttle to 100%.
If you screw up, there is a back-stop, and that is the reactor operator. The reactor operator can always insert the control rods slightly if the throttleman gets overzealous. Unnecessary control rod movements are frowned upon, however - It shows a lack of proficiency (or worse, professionalism) from the throttleman. If the throttleman was in the process of screwing up, the other maneuvering watch-standers would inform him to cut back before it became necessary to use the control rods. It's a very well-trained and high-quality team in the maneuvering room, but the throttleman is the most junior of the bunch. As a result, he is well-monitored.
Operating the throttles can be exhilarating during casualty drills and during maneuvers, but for the most part, it was boring. Boring boring boring. If the ship is transiting across the ocean, you might spend an entire 6 hour watch doing a lot of nothing: Taking the exact same log readings at the top of each hour, without ever adjusting the throttles once.
You would typically begin throttleman training even before you were fully qualified AEA - say at about the 6 months point. You would be qualified in 10-14 months or so, and be really good at it by the time you were aboard 1-1/2 - 2 years. As you gain seniority, you would work less and less at these junior watch stations, until eventually you stood watch once per month for proficiency, because newer sailors would stand the majority of these watches.
In the next post on this topic, I'll discuss the more senior watch-stations: Electrical Operator, Battery Charging Electrician, and Engineering Watch Supervisor. This post has gone on long enough!
Part 6 is here:
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