"Ahead two thirds on number two engine, Emergency surface!" Not exactly a command out of the book. It happened - in a way; here's the story:
On numerous occasions, while operating with destroyers and carriers in the Tonkin Gulf during the VietNam War, we exchanged 'observers'. Enlisted men, and sometimes an officer or two, generally from Sonar or C.I.C. (Combat Information Center) teams, who were training in A.S.W.(Anti Submarine Warfare) techniques, would come to the Sabalo for a couple days to see what our methods entailed.
Swapping of men was somewhat necessitated by the fact that bringing on five or six more bodies just made the living arrangements on Sabalo all the more cramped. So generally, a like number were sent off to keep the crowding from occurring. Sometimes Sabalo sailors sent over to visit them were not of ratings that participated directly in the exercises, but included other ratings who wished to see what the skimmers did for a day's pay.
On one particular swap with a destroyer, we had among the group, a couple guys who exhibited a little more that the normal fear and claustrophobia, and later found a reason to exhibit it. ...But I'm getting ahead of myself.
We had had a failure of number 2 engine (port side engine in the forward engine room). The enginemen were taking advantage of the submerged activities of the ASW exercises to do rebuilding work. It was nighttime; we were at 150 feet, and enjoying the calm. A movie was underway in the after battery. With the guests in attendance, it was standing room only, and none of that could be had.
Suddenly, the engine under repair cranked over and lit off. It occurred because of the following, later reconstructed events. One of the men working in the lower flats requested someone above to bump the air start over to ease access to a connecting rod for tightening of the bolts. What was forgotten was that the linkage to the fuel shut-off valves had been disconnected. However, the lines were still connected, and fuel was still able to get to the injectors. Unfortunately, the air start rolled the engine enough so that it fired, and now with the valves in the open position, and the linkage disconnected there was no way to shut it down.
Now having an engine sucking air from inside the boat for a short time happened at least a billion times in the history of snorkel boats. If you've been there, no further explanation needed. If you're not sub familiar, I'll explain. When snorkeling, if the head valve where air is inducted goes underwater, then an engine uses air from inside the boat to remain running until the valve again comes above the surface. If seas are rough, then this may occur very often.
However, 150 feet is too deep for snorkel operation so the air used to make the engine run was being sucked from inside the hull which causes a vacuum to be created. Too much vacuum is dangerous to personnel. To monitor how much vacuum is being created, an altimeter is mounted at the diving station in control. If the vacuum, or altitude, becomes too great while snorkeling, then a command is given to shut down the engine(s). This was usually at 7,000 feet above ambient, if I recollect.
Back to our movie hour - In this case there was no way to stop the engine. Once the situation was realized - actually, very quickly - we sounded emergency surface, made an announcement on the underwater telephone, and started a large up angle.
I was positioned in the after battery, under the hatch, at a poor angle for viewing the movie. Most of the important communication was via the phone to control. What we were experiencing was a lot of yelling, and smoke getting thicker by the second. The situation in this case was not the eventual problem of the vacuum created, which usually took a minute or more to reach limits, but the exhaust. During snorkeling, exhaust is still discharged through the snorkel even if it is underwater. In fact, that is generally what is desirable, i.e. exhaust when snorkeling is generally a few feet under the surface. Instead, now all the exhaust was coming inboard.
We assumed a sizable up angle, and everyone not scrambling to do something about the problem was hanging on. The IC man operating the projector was unable to keep his position and keep the projector from tipping. I was looking right in the eyes of a couple of the skimmer visitors, and it was a look of fear I had never seen.
I'm sure some in the crew were apprehensive also, but sub sailors have a special temperament which comes from knowing the boats intimately. During the process of becoming "Qualified in Submarines" every detail of the boat is learned, and it becomes as familiar to them as anyone is to doorknobs and light switches in their home. In an emergency they react according to their training, forget their fallibility, and remain confident even when a situation might be precarious.
The smoke became very heavy. Visibility was only a few feet. Choking was common. Everyone in the engine room was evacuated, and the water-tight doors sealed. The boat broke the surface and leveled out. The bridge hatch opened. (With a vacuum inside the boat I forget how this is accomplished.) The engine, however, didn't give up that easily. It sputtered, spurted, and struggled to continue running for what seemed ten minutes before finally going silent. Chaos of some level had taken over for a few minutes, but when the air cleared, it became evident that the danger had passed.
A fire fighting team assembled, and a short time allowed to pass, before the hatches were opened. There was no real sign of what might be going on in the engine room. The sight windows in the hatches were totally blackened.
The room was finally opened and a ventilation lineup immediately started. The nature of the mess was now revealed. The entire room was covered in black soot and wet, partially burned fuel oil. And I mean it was like a spray gun with black paint had put on ten coats.
The cleanup began immediately, of course. Not being an enginemen, I wasn't directly involved, but did spend some time, as did most of the crew at various times in the next couple days with rags and cleaning gear trying to do what was possible. Because the regular rag supply was quickly depleted a plea went out for anyone with worn clothes, about ready for retirement, to donate them for use as wiping rags in the effort . I gave up a half dozen sets of skivvies and a shirt or dungarees.
What I remember is that those skimmers couldn't get ready for departure quick enough once the sun came up. I doubt that either of them got any sleep, or even closed their eyes the rest of that night. The look on their faces as they departed was still one of nervousness. What a tale they had to tell their shipmates.
I don't remember the sequence of the following days, and if we were excused from the present assignment to go lick our wounds or not. I suspect we barely said a word and kept the incident as quiet as possible. Such things have a way of reflecting negatively if the skipper has to explain much to superiors.
Shortly our schedule took us into Hong Kong for liberty. At Victoria Basin, the British facility, where boats were able to tie-up alongside, we executed the final cleanup operation. Our best comshaw team was put in the negotiating mode with "Mary Sue", or whomever is that legendary figure who controlled all of those unofficial, Chinese, female 'yard workers'. I guess we traded a bunch of old mooring lines, or some brass bearing inserts, or something, but "Mary Sue's Girls" came on board enmasse. They are famous for ship painting and cleaning. There must have been 50 women in that engine room with buckets of water and detergent, and a ton of rags. They were singing, and dozens of conversations were going on, which to someone schooled only in English, sounds like just so much gibberish. I swear it wasn't much over four hours and things started to look respectable. There was still a lot of soot in crevices, cracks and especially the armor braid of all the cable runs. A complete paint job was the next order of accomplishment by the 'girls'. Top notch job - all the way.
Not being an engineman, nor intimate with the full details, or any repercussions, I am unable to report anything further except to say it was one of those experiences you remember, but in the order of things didn't seem very earthshaking then, or now.