Fire May Leave US Nuclear Sub Damaged Beyond Repair 228
Hugh Pickens writes "AP reports that a fire that swept through a nuclear-powered submarine in dry dock at Portsmouth Naval Shipyard has caused such extensive damage to its forward compartments that the 22-year-old Los Angeles-class attack submarine might have to be scrapped. 'These submarines were designed decades ago. So they're no longer state of the art,' says analyst Loren Thompson. 'If this vessel returns to service, I will be amazed.' The fire broke out while the Miami was on a 20-month stay at the shipyard for an overhaul, and it took firefighters from more than a dozen agencies twelve hours to put out the fire, described as intense, smoky, and a 'hot scary mess.' 'It takes a lot of guts to go into a burning building. But the idea of going into a submarine full of hot toxic smoke — that's real courage,' said U.S. Rep. Chellie Pingree after meeting with the shipyard commander. Firefighters isolated the flames so they would not spread to nuclear propulsion spaces at the rear of the submarine. There was nuclear fuel on board the sub, but the reactor has been shut down for two months and was unaffected. Rear Admiral Rick Breckenridge says an investigation has been launched into what caused the fire, but he expects that investigation to take a long time to complete and wouldn't say if human error has been ruled out as a cause of the fire, or if the focus is on mechanical issues."
Re:Had bad experiences when I was 22 and in port t (Score:3, Informative)
There's a few reasons. First off, there's no way to shut off the oxygen on a sub from the outside, so the fire had to be controlled for that to happen. Second, the sub may be old, and it may end up being scrapped, but those things are expensive as hell, and they had to try to save it. Third, the top priority was making sure the reactor was safe, it would be a bit dangerous to just shut the door on a burning nuclear reactor and just cross your fingers that it goes out before something catastrophic happens.
Sounds Like That's What They Did (Score:5, Informative)
Two crew members, three shipyard firefighters and two civilian firefighters were hurt, but their injuries were minor, officials said. Officials were waiting Thursday to begin venting smoke and noxious fumes so workers could go inside the submarine to assess the damage. Workers had to let fire-damaged compartments cool enough for fresh air to be safely introduced without risk of another fire.
Re:Cities... (Score:5, Informative)
Re:Cities... (Score:2, Informative)
You almost got it. It's at the Portsmouth Naval Shipyard (named for Portsmouth, New Hampshire) which is in Kittery, Maine.
Adding fuel to the fire: the Miami is based out of Groton, Connecticut.
Re:I don't understand how this is possible (Score:5, Informative)
The USS Miami was my first boat, 1998-2003.
Yes, there is a possibility this was bedding. Usually though, when you go into an overhaul like this, all the bedding is removed. The mattresses may or may not have been removed.
There is a lot of wiring that is bundled together around ships. There is also quite a bit of temporary equipment that is brought on the ships during overhauls like they were doing that could have been the source as well.
There is no "fire suppression system" as you might imagine. Normally all firefighting would have been taken care of by the 130 man crew. Portable extinguishers only go so far, and it seems that this was far beyond a few extinguishers.
I stood my fair share of watches in the engine room. I knew this day would come sooner or later. I'm sure that the nuclear operators stayed at their watch stations during all this. This is a hell of a way for the Miami to go out.
Can do, will do, glad to.
First to fire, twice to fire.
SSN-755
Re:Had bad experiences when I was 22 and in port t (Score:5, Informative)
My first guess of how this fire happened is that someone had done some welding in a compartment and something caught fire. Usually the Navy is pretty good about removing flamables in the area. They even go so far to have a "fire watch" for several hours after the welding was done to ensure that nothing catches fire. it will be interesting to hear what the root cause is.
Another interesting fact about L.A. class submarines, of which the Miami is included. There is only one water tight door interior to the sub, and that is the one that separates the forward part of the ship to the rear (ie engineering which was apparently not affected). Compare that to the submarine that I was on (Sturgeon Class), there were two water right doors for just the forward part of the ship, and two in the engine room. Basically, if you ever have flooding in an LA class sub, you are going down. At least in a Strugeon class, if 3 of the 5 compartments were completely flooded, you could still survive.
Re:Had bad experiences when I was 22 and in port t (Score:5, Informative)
Re:One ship lost for the navy (Score:5, Informative)
What will likely happen is what has happened before. The oldest LA class boats are the ones being replaced by the Virginia class, so they'll promote the Miami down the list to be written off against the next Virginia instead of whatever boat was scheduled for scrapping. That boat will then get an overhaul instead of being scrapped.
Been done with destroyers, carriers and subs in the past if my history memory isn't full of holes.
Re:Had bad experiences when I was 22 and in port t (Score:4, Informative)
When metal burns, depleting it's oxygen supply doesn't always help. When I was in, the SOP for burning metal was to push it overboard and let it sink to the bottom where it could burn out safely.
Really bad if the battery catches fire (Score:5, Informative)
There is a 250 volt battery with a huge amount of potential energy. You have basically a medium size bedroom full of batteries that are 6 feet tall.
The battery can keep the lights running for about 1.5 hours while also supplying power to move it through the water and power the reactor plant to do a restart.
We calculated one time that if all the energy in the battery was released at once (not possible, we knew that), it would blow the sub 1.5 miles into the air.
Re:Had bad experiences when I was 22 and in port t (Score:5, Informative)
Pardon my ignorance here. But I have a question.
I know that fire in a sub is considered one of the most dangerous threats there is (every crew-member is trained in fire suppression on a sub). But since this ship was presumably unmanned and in dry dock, and presumably also still air-tight, why didn't they just close all the hatches in the effected areas and shut off the oxygen? I can't imagine a fire in such an enclosed space would last very long without incoming oxygen.
I am a former submariner.
1 - A submarine in dry dock is basically a ship on ship. A problem on one constitutes a problem on the other.
2 - There is a lot of piping throughout the boat. It contains either oxygen (@ 10's of PSI) or hydraulic fluid (@ thousands of PSI). If the piping burst, its source is a giant tank containing much more of the stuff in a different location of the boat. There are isolation valves, however, which may mitigate the problem for a while.
3 - There's this thing called a nuclear reactor. It's shut-down while in dry-dock but still requires power to keep it safe.
4 - Separating the reactor and the forward compartment is a giant tank containing thousands of gallons of diesel fuel oil. If it over heats, well, yeah, kiss your asses goodbye.
5 - There's a HUGE battery on the boat for when the boat needs to run off of battery power. It contains an enormous amount of energy - so much so that if it caught fire and exploded, the sub, the dry-dock and the facilities surrounding it would be damn near vaporised. I think anything within a few miles would *easily* have its windows blown out if not flattened.
6 - If the reactor has a problem, you'll basically have Fukushima on your hands.
7 - Submarine fires (when the get large enough) dont stay a single class of fire for long. There is too much hydraulic fluid, electrical line and combustible materials for it to remain one class of fire for long - ergo, one can not simply spray water (seawater, btw) to extinguish it.
So, no. Shuttering the place up and trying to starve the fire isn't exactly a proactive manner to extinguish a fire.
Throw in skeleton crews (most systems shut down), lots of welding, oil and whatnot all over the deck and you have a recipe for disaster on your hands. I'm surprised there arn't more fires of this magnitude more often.
More questions? Guess I'll read below and answer some there, too.
Re:Had bad experiences when I was 22 and in port t (Score:5, Informative)
yep, fire is usually considered the #1 hazard aboard space ships and subs. Simply because the first thing you normally do when there's a fire is evacuate, something that's not such an easy option for them.
Evacuating ship is *not* the first thing submariners do. They attack fires with a vengeance. One, it's stealing our oxygen. Two, it's polluting our oxygen supply with *deadly* gases. Three, it can kill you fairly quickly. Some exhaust gases on board submarine cause damn near instant death.
And that's just compounded by the low availability of breathable air.
Actually, you're close. Underway (that means out to sea) subs purposefully keep their oxygen levels low - very low. So low that a cigarette will immediately extinguish when the smoker is not inhaling. It must be re-lit before each puff.
But that's not important. The important part is that whatever is attempting to catch fire would smoulder for a bit before flaming up - thereby catching the eye/ear/nose of the watch or any other passing crew member.
In port, oxygen levels are normal to the atmospheric oxygen levels of the surrounding city. (By the way, Norfolk, VA smells bad. - Norfolk sub sailors know what I'm talking about. ;P )
I don't know on the hatches, I'd expect a sub to have the usual complement of watertight compartments, so as long as the fire didn't get hot enough to melt or deform bulkheads (which it may, which is why they stopped using aluminum for warship superstructure) they should have simply been able to close the doors.
Let me address this. While in dry dock, the boats have all kinds of cabling in the way preventing hatches from being closed. Forgot about that in my first post on this topic. So, no, you typically cant just walk up and close the hatch - not that you'd want to. See my previous post, above.
But maybe they had problems getting the people out first. Subs don't have too many doors on them, and if the fire is between 25 crew and the door and there's no other route, sealing off isn't an option.
I find it hard to come to a conclusion where this would become a problem. There are multiple exits in most areas that are 'dead ends'. There'd have to be a pretty messed up situation that prevented ~25 people from escaping a location without them trying the emergency route *before* the emergency route became blocked.
Re:Had bad experiences when I was 22 and in port t (Score:4, Informative)
The third of the crew requirement is so they can man at least one watch fully and get underway. But they're not getting underway when completely shutdown, in the shipyard, in drydock, with the reactor de-fueled, at night... under those conditions, there would have been only a handful or so of crew onboard. Maybe three forward, four aft, and two topside. The balance of the duty section would have been asleep on the residence barge or in the barracks.
For that matter, there's probably not even a full crew assigned or present at the moment. When a boat goes in the yards, they transfer non-essential and junior personnel away. Of the crew that remains, a fair portion will be away at schools or temporarily assigned to other boats either for experience or to keep their skills sharp.
(Been there done that when we brought the 655 out of overhaul at Newport News.)
Re:Had bad experiences when I was 22 and in port t (Score:4, Informative)
Former Navy Nuke
Not necessarily. Once the reactor has been shutdown long enough, it no longer requires power to cooling pumps to maintain temperature.
Umm, no.
If you're underway, and things go so completely south that every failsafe in the system fails unsafe, then your boat is going to sink.
If, on the other hand, you're in a drydock for an extended maintenance cycle, then the reactor has been shutdown long enough to be cold, and you won't even need the Main Cooling Pumps to keep things stable and safe.
Note that, whatever other problems they may have, Navy nuclear powerplants don't keep spent fuel rods laying around to cause problems...
Re:Had bad experiences when I was 22 and in port t (Score:5, Informative)
And that's just compounded by the low availability of breathable air.
Actually, you're close. Underway (that means out to sea) subs purposefully keep their oxygen levels low - very low. So low that a cigarette will immediately extinguish when the smoker is not inhaling. It must be re-lit before each puff.
But that's not important. The important part is that whatever is attempting to catch fire would smoulder for a bit before flaming up - thereby catching the eye/ear/nose of the watch or any other passing crew member.
In port, oxygen levels are normal to the atmospheric oxygen levels of the surrounding city. (By the way, Norfolk, VA smells bad. - Norfolk sub sailors know what I'm talking about. ;P )
This is not correct. Actually the atmosphere in the boat while underway is 19-21% oxygen. Atmospheric oxygen levels are around 20% worldwide. The atmosphere on the ship is no different in any way from the atmosphere that you are currently in most likely (gas wise). What IS different is the pressure which changes with the depth the ship is at, the amount of time since the ship has "equalized pressure" by putting the exaust mast up, and the amount of people on the ship (you all breathe out more than you breathe in).
And this is where *your* boat took chances. Our boat kept the oxygen levels at about 13% to 15%. Yes, you read that correctly. Again, the smokers had to inhale *deeply* while attempting to light their cigarettes so they could create enough air-draw across the surface of their *lighters* to get the lighter to even light so they could light their cigarette. Low oxygen levels starve fires.
You say you've been in 3 fires and they were extinguished within 10 minutes? I'm very glad you did. However, wow. Amazing. How many captains did your boat(s) go through? While we had our own scares we only had 1 real fire on board while underway and it was nothing more than a smoking rag. Someone left it on top of the CO2 Candle where it began to smoke. It was amazing. I was one of the few who showed up in an EAB. Three guys showed up in their skivvies. People were on it *instantly*.
The only other time we had a near miss (and the scariest moment of my life, hands down) was when our 4500lbs Hydraulic line ruptured in the engine room. It was spraying 4500lbs PSI hydraulic fluid into the engine room. If the roving watch underway hadn't been standing *right* next to the kill switch when it ruptured I might not be here today. We surfaced and remained surfaced for 3 days drawing circles on nav charts in sea state 3 to sea state 4 seas. If the oxygen levels were any higher AND (I stress AND) the fluid would have sprayed at 4500psi for more than 30 seconds, it would have been a flame-thrower.
It's purely up to the CO on what level of O2 he wants the boat to run around at. Maybe they've enacted some regulation since I got out in late 1996; but, don't sit there and say I'm not correct. Certainly, in port the ship's O2 levels are in keeping with the surround local atmosphere - ~20%. Our boat kept O2 levels low purposefully under-weigh.
But maybe they had problems getting the people out first. Subs don't have too many doors on them, and if the fire is between 25 crew and the door and there's no other route, sealing off isn't an option.
I find it hard to come to a conclusion where this would become a problem. There are multiple exits in most areas that are 'dead ends'. There'd have to be a pretty messed up situation that prevented ~25 people from escaping a location without them trying the emergency route *before* the emergency route became blocked.
Okay so oddly enough there isnt really an "emergency route" on the ship for reasons that I wont detail here (it would take too long to explain). I do have to say that there are contingency plans in place for this kind of thing un