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Old 03-20-07, 05:27 PM   #2
unruhly
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Join Date: Mar 2007
Location: Central Virginia
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Default Extreme Angle

This thread has been begging for a story. I hope you enjoy it while waiting for your game to arrive.

Extreme Angle
The boat had spent some time at a Florida port, probably Port Everglades. Before leaving, we had taken on some important guests. If memory serves, they were Norwegian Navy officers. We were taking them on a short “demonstration” trip to strut our stuff and show them what the U.S. navy was made of.

After the maneuvering watch was secured, I had the 12 to 18 which meant I would have twelve hours off between 1730 and 0530 – an ideal daily schedule almost like shore life. This only happens one day in three while underway, and it allows one to enjoy an almost “normal” night’s sleep free from the prospect of drills or field days. Usually, that is.

An hour or so after dinner, I was in my rack reading a Stephen King novel. I usually had trouble sleeping when the boat was surfaced but not because of the motion from the waves. It was the sounds of the lapping water rushing over the hull that intrigued me so. It was so peaceful and calming, that I didn’t want to miss hearing it. The sea that afternoon was very calm, which added to the tranquility, and as I lay in my rack, I could feel the gentle sway and hear the slight creaking of some metal on metal somewhere within the ship.

The 1MC bellowed, “Dive! Dive! Dive!” as the Klaxon horn sounded. Usually we all looked forward to the dive in order to escape the rough rolling seas. This time however, I actually wanted to stay on the surface. I was getting sleepy and was ready to succumb to darkness when the sound of the diving alarm quickly snatched that away. There is always high tension at the onset of a submarine’s dive. There are just too many things that can go wrong to be comfortable with it.

The sound of the air escaping from the ballast tanks was loud, and as normal, the boat continued running on the surface. Then slowly, the bow began angling down as the ship started it’s decent towards the depths. From the inside, it’s almost imperceptible at first as the “angle” during an initial dive from the surface is very conservative. Submerging dives are made very carefully.

From outside the boat, an observer would have been able to see streams of water shooting upwards from both ends of the boat as the ballast tank vents opened and allowed the air in the ballast tanks to escape. The forward vents are opened a couple of seconds before the after vents, so the forward tanks fill slightly sooner than the aft tanks. This helps the boat achieve the down angle needed to descend into the depths. If an observer had been watching that day however, he may have noticed that there was not as much air gushing out of the aft tanks as there should have been.

Lying in my rack, I felt the boat pick up the normal slight “down” angle as we submerged. I subconsciously expected it to stay that way. During my very first dive, I was sort of disappointed about how little you see and hear. It’s less dramatic than, say, taking off in an airplane. You feel the deck tilt a little. And if there is any swaying from the waves, it stops. That’s about it.

This time was different. The slight down angle began growing steeper.

688 class boats are designed to be “tilted” up or down by as much as 45 degrees. These are called, appropriately enough, “steep angles” and they are rarely done in peacetime. A normal or typical up or down angle, when the boat is fully submerged, is more like 20 or 30 degrees. Down angles when submerging are probably no more than 10 to 15 degrees.

Even laying in my rack, I could feel the down angle increasing. Soon it was about 30 degrees, about the maximum considered normal. Since my feet were pointing forwards, this meant I could feel a bit of pressure on the bottoms of my soles as they began to press against the bulkhead at the “foot” of my rack. I was partially “standing up”. My first thought was, “Those show offs! The XO is trying to impress the Norwegians with some sort of steep dive.”



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The angle grew steeper.

Soon it was at 45 degrees, the most I had ever felt. This may not sound like much of an angle, but it means that it’s just as easy to walk down the bulkheads, as it is to walk down the decks. Mobility is in fact impossible. All you can do is hang on. The crew needs to prepare the ship before such steep angles, or it can be dangerous from falling objects.

I heard the expected outcries of surprise, liberally sprinkled with profanities. Shoes and sneakers tumbled across the deck, and I heard loud crashes from the galley.

The angle grew steeper. Now, the bulkheads were more horizontal than the decks. I wasn’t just anxious about the dive anymore, I was down right scared. I knew something was wrong as I was basically “standing” on the foot of my rack. I was almost paralyzed with fear wondering what the hell was going on. There was nothing that I could do other than to trust my shipmates in the control room. At that point I think I shouted, “Blow damn it blow!”

The angle continued to grow even steeper, maybe to about 60 degrees. I kept thinking to myself, “C’mon guys, this aint right. Blow the f'n tanks or we’re going to loose the ship!”
At that exact moment, I heard the distinctive roar of the Emergency Ballast Tank Blow system being activated.

I wave of relief came over me almost instantly. “Whew that was close. The chief of the watch messed up his trim tank calculations. Stupid idiot!” We should be ok now. The angle should start decreasing and we will head back to the surface and recalculate the tank levels. The high-pressure air having pushed the water out should be bringing us back to the surface.

Except that it did not.

The angle grew even steeper still. Right through to 70 degrees. For all practical purposes, we were vertical. The sound of the EMBTB system air was heard again and again. I knew from previous experience that when the EBTB system was used, it WORKED; it took just a few seconds of air to bring the boat to the surface.

It wasn’t happening. The ship was not responding.

I heard a very weak voice come from the 1MC: “Loss of depth control.”

The wave of anxiety rushed through me, but when I heard this, I knew my time had come and I accepted that.

Amazingly, I could still think straight and panic wasn’t even a shadow of a thought. I wondered if the air was just escaping right out of the ballast tanks grates, without having any effect since we were almost vertical. I believed that we would die within a few seconds. Crush depth for a 688 class is not all that deep. I heard the hull flexing and popping as we descended deeper and deeper.

The mind begins to work in funny ways under these conditions, I guess. An incredible emotion swept over me. I guess you expect me to say that I felt peaceful, almost relieved. That’s not how I felt. The feeling was one of intense despair and sadness. It was an almost indescribably dark and miserable feeling, everything negative that you can think of, all rolled together: anger, disappointment, sorrow and terror. It was beyond a doubt the worst feeling that I have ever had.

I wondered how cold it would feel for the brief second that I would still be alive when the water rushed in to seal our fate. Suddenly, I wanted it to be over. I could only hope that it would be quick. The hull continued to make popping sounds under the immense pressure of the depths. When it finally gave way, I wondered, would there be any sensation at all? Would I feel like an ant being crushed under a steamroller? Would there be an avalanche of intense, infinite pain just before the abyss of death? Or would my mind just “snap off” like a light, with no final sensation at all? That’s what I was hoping for. I was afraid that somehow I would survive the implosion for a while causing me to feel the sea water being forced down my nose and throat, filling my lungs to capacity and drowning me like a bilge rat.

So what will it feel like to die, I wondered? I honestly believed that I was about to find out. As I waited, I felt the boat begin a slight shudder.

Gradually, the angle began growing less severe. Soon we were at 60 degrees, 45, 30, then horizontal. I don’t remember being “relieved” at all – I was too emotionally exhausted to feel a thing. I just spewed four letter words with my shipmates, and that took off some of the edge. A time-tested sailor’s trick.

On the surface again, we took it for granted that we would NOT try the dive again until we knew exactly what went wrong – and it was fixed. Just minutes after we had re-surfaced, word spread that the Executive Officer, wanted to try the dive again immediately. Even before the EBTB tanks were re-charged with high-pressure air. Fortunately, the captain had more sense. He made an announcement to the effect, “The ship will not, I repeat NOT, attempt another dive until the problem is found and rectified and the HP air tanks have been re-charged.” Now the wave of relief finally came.

I think there could have been a genuine mutiny that night.

Apparently, one or more of the after ballast tank vent valves had stuck shut. Because air couldn't escape from one or more of the aft tanks, there was a large bubble of air back there, holding up our back end as the front end submerged deeper and deeper.

What saved us? I don’t know. I suspect that the extreme depth made the bubble in the aft tank smaller (air is compressible, of course) and that decreased its effect, enabling us to regain control of the boat.

I have no idea how deep we went. No one really knows how steep the angle was as all the bubble indicators were maxed out. Scuttlebutt says that the Sperry gyroscope in the torpedo room trips at 75 degrees, and it tripped. The reactor too is supposed to automatically shut itself down at an extreme angle. I was told that something went wrong with the sensor, and that’s why it remained running. If it had shut down, it would have been the end for sure since we were using "Emergency Back Full" reverse to help slow the descent into the depths. Without the propeller spinning to help hold us back, we would have shot like a torpedo to the ocean’s floor. Divine intervention? I would like to think so. On this day, we all walked away lucky to be alive.
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Last edited by Gizzmoe; 03-21-07 at 12:22 AM. Reason: Changed text color
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