Damage Control

[kaladorn]

In reading a bit about Pearl Harbour, and having a friend who attended Navy firefighting and damage control school, I've wondered how such things are actually affected in the Traveller universe, and what actions people in DamCon parties aboard IN vessels actually take.

I suppose they'd do things like:
- worry about airtightness
- worry about rescuing injured crew members
- worry about re-routing power from the plants to key systems (like guns/scans/etc)
- worry about preventing or addressing explosive or other gas or fluid leaks
- worry about fires in areas still filled with air (or being fed by oxygen leaks or the kinds of fires that are capable of burning in space - plasma stuff, or electrical arcs.... I guess not really *fire* but still a problem)
- worry about things like grav plates and inertial compensators
- fix damaged systems (at least jury rig them) including sensor grids, computer systems, fire control feeds, thrusters, etc
- worry about explosion risks from the fuel tanks or power plant or the batteries or Life Support or other places

One thought I particularly had related to getting power to sections of the ship from the power plant after damage had 'cut it off'. Particularly, to the guns, but the solution I have in mind applies more generally. I thought this up while reading about Pearl and the handraulic ammo transfer lines between mags and guns once the lights went out on the ships.

Idea:
Near each key hatch coaming is a power transfer box. Normally, it does nothing. It is, in essence, a huge plug (on each side). It serves one function: if the normal power feeds go down, it offers a way to get an emergency power feed (a large cable about the side of a man's lower leg in diameter) through an airtight bulkhead or shock frame. (That is to say, without compromising the airtight nature of the other side).

Engineers run these large cables (and they have these stored in lockers around the ship for access in emergencies) from power take-off (PTO) points throughout the ship (from one that works, back near the power plant, say) and run them along corridors and such (using these power transfer points - PTPs - to cross any airtight doors) to an emergency power feed point (PFPs) near the system in question, be it a turret or a scan mount or even the bridge. This gets power to those systems even if all normal conduits have been cut, as long as the plant is up. There are also these kinds of PTO points near the ship's battery farm, in the event the main fusion plant is offline.

I also figure all damage control folks (or a goodly number) would use a modified form of battle dress (less armour, more tools - probably about equivalent in armour to a combat environment suit or thereabouts) with muscle augmentation, cutting torches, prybars, impact drivers, firefighting gear, etc. aboard and specialized software, etc. to drive it.

 

[flykiller]

your description of emergency cable systems is exactly how it is done in the modern navy.

vacc suits would be standard for any sort of DC situation.

firefighting would be tricky. the easy way to fight a fire would be to vent, and presumably fires could be fought with halon or halon-like chemicals, but starship air volumes would be terribly limited and dumping air into space or filling it with chemicals may not be pleasant options. ships would be designed with a minimum of flammables and explosives aboard - 'course, regulations may not always be followed. saw some gross violations of regulations and common sense when I was in the navy ...

every ship would have damage control lockers with vacc suits, rescue equipment and air bottles, radiation detectors, IR sensor equipment (hot air and metal frequently don't look hot), powered prying equipment, lights, tools, parts, fuses, spare fluids, hull patches, suction grips for hands and feet (zero g), lots of vacc suit patches, and whatnot.

in the modern navy, along with all the traditional ratings there is a new rating, damage control man. this translates easily enough into a traveller skill like the others. such an individual will have specific training in fire suppression, hazard recognition and avoidance, hull integrity evaluation, atmosphere maintenance, access, emergency repairs, power cable rigging, tool use, and rescue ops. in ordinary situations he would be responsible for gaskets, life support, and other hull integrity maintenance and accessibility issues.

in the military shiny shoes are required, and navy personnel frequently wore "coreframs", plastic shoes that always stayed shiny. in 1981 (?) when the iraqi airforce accidentally missiled the uss stark, crewmen fighting the fires found that these shoes melted on their feet. in DC little details tend to gitcha. toss in vacuum and damaged unpredictable g fields and you can have a nice day.

 

[kaladorn]

Originally posted by flykiller:
your description of emergency cable systems is exactly how it is done in the modern navy.

Darn. Guess I won't get the patent, now will I?

vacc suits would be standard for any sort of DC situation.

I figure the augmentation of strength for clearing debris and the hardening of the armour in a light (armour wise) version of battle dress, plus the on-board control interfaces for tools, sensor remotes (for finding trapped people or investigating badly junked areas, etc) argues for that being better than normal Vacc Suit.

OTOH, Vacc Suits would be the standard wear of those who are not specialists in this area, except for Marines, who'd get their normal BD on. Many of them are probably damage control trained too.

firefighting would be tricky. the easy way to fight a fire would be to vent, and presumably fires could be fought with halon or halon-like chemicals, but starship air volumes would be terribly limited and dumping air into space or filling it with chemicals may not be pleasant options. ships would be designed with a minimum of flammables and explosives aboard

And there may still be personel not yet in vacc suits in those sections (or with ruptured ones, who are injured). So the threat of fire vs. the immediate death by Exp Dec of the crew in the sections will have to be weighed (as are issues of recovering any key atmosphere components....)

- 'course, regulations may not always be followed. saw some gross violations of regulations and common sense when I was in the navy ...

Aw, and here I thought the Navy had no common sense or regulations... <*yes, I was a gropo...*>
(The irony being I've now become fascinated with sailing, tall ships, coastal nav, etc)

every ship would have damage control lockers with vacc suits, rescue equipment and air bottles, radiation detectors, IR sensor equipment (hot air and metal frequently don't look hot),

Esp in areas where there isn't any air anymore!

powered prying equipment, lights, tools, parts, fuses, spare fluids, hull patches, suction grips for hands and feet (zero g), lots of vacc suit patches, and whatnot.

Add in screw-braces (or perhaps self powered grav braces by high TL) and other materials for performing structural integrity jury-rigging/repairs and keeping things from collapsing.

Medkits, Rescue Balls, Comm dots (ship comms could be down), small remote sensing units (grav operated perhaps) that could be sent in to explore areas that are damaged and look for survivors, etc.

in the modern navy, along with all the traditional ratings there is a new rating, damage control man. this translates easily enough into a traveller skill like the others. such an individual will have specific training in fire suppression, hazard recognition and avoidance, hull integrity evaluation, atmosphere maintenance, access, emergency repairs, power cable rigging, tool use, and rescue ops. in ordinary situations he would be responsible for gaskets, life support, and other hull integrity maintenance and accessibility issues.

Sounds like Med-0, Sensor Ops-0, Mechanical-1,
and if we had them DamCon-1 and perhaps LifeSupport-0. Also add Vacc Suit-1 and ZeroGEnv-1.

in the military shiny shoes are required, and navy personnel frequently wore "coreframs", plastic shoes that always stayed shiny. in 1981 (?) when the iraqi airforce accidentally missiled the uss stark, crewmen fighting the fires found that these shoes melted on their feet.

The Brits found out when the Argies missiled the Sheffield that Nylon Work Dress did the same thing. Can you say "Debrided"? If you don't know what that means, look it up. Grotesque, if I do say so myself. Give me cotton and wool any day.

in DC little details tend to gitcha. toss in vacuum and damaged unpredictable g fields and you can have a nice day.

Yes, another couple of things that now occur:
Zero-G gear (mag boots, mag gloves, thruster units)
Local Grav Stabilizer (portable CG unit that has a fast-reaction CPU to help counteract a pulsing/messed up/gone loco inertial comp or grav plate on a ship - at least until power can be cut...).

 

[The Oz]

As a person who did these kinds of things for the US Navy for many years, I'd say you've got the right kind of ideas, kaladorn.

I like the idea of powered damage control suits with lots of tools, sensors, etc. You'd have one or two people with such suits assigned to each damage control locker, and some "Tiger Teams" composed almost entirely of people in such suits under the command of Damage Control Central for dispatch to areas that really need help.

You always have to prioritize your DC efforts: you plan for more damage than you have people, so you have to pick what comes first. In the USN, flooding was always #1 priority, firefighting usually #2, with personnel rescue/aid #3 in a close tie with restoring power to vital systems.

In space flooding is not a concern. Firefighting is not that serious either, thanks to all that vacuum outside (and the enemy probably let that vacuum in when he started the fire with his missile hit, anyway). That puts rescue ops and ship's system repair up as your main priorities.

The most vital systems (IMHO) would be maneuver drive and attitude control: it's hard to do anything if you can't point in the right direction. After that would be sensors and computers, followed by defensive systems (although that could change depending on the tactical situation).

Usually the person who sets the priorities for damage control is the Damage Control Officer, who is the combat job of the Executive Officer or the Chief Engineer. If necessary the Captain will make specific demands on Damage Control ("I need that meson gun back now!!!") but usually the DCO decides on what gets worked on first, using his understanding of what the Captain would want done first.

 

[Tanuki]

If "battle stations" drill meant everyone in vacuum suits and the ship at reduced air pressure -- pump everything down to 3 psi or so if there's time -- that would much reduce the problems of explosive decompression. Then all you have to worry about is a fuel hit filling your compartment with liquid hydrogen. BRRRRRR....

Ships in alert status might run at reduced pressure (mostly O2) for days at a time.

 

[kaladorn]

My impression was your order of concerns would be:

1) Any explosion or runaway power plant scenarios or any structural damage that might risk the ship if thrust was applied
2) Flight control (thrusters, avionics, etc) and probably as a consequence, some types of sensors (can't fly if you can't see, at least not safely)
3) Grav plates and intertial comp (If I have to pull 6 Gs, then I'd love to have the comp working)
4) Either Jump Drive or Defensive Weaponry (and sensors to back up either) as prioritized by the DCO and the decision "am I running or fighting?" or perhaps, if you had orders to that effect, Offensive Systems ("Scotty, I need Phasers NOW!").
5) Personel rescue
6) On-going repairs of structure, long term life support issues, airworthiness repairs, etc.

I think the DCO might be a separate job on big enough ships, no? And any Marines that weren't required to man secondary batteries or who weren't 'broken out' for the defense of the ship could be used (and probably are trained) for DC Ops.

As my friend in the Canadian Navy pointed out to me lately, the ship's officers and crew exist for the purpose of fighting the ship and doing what is required to support that - driving it, navigating it, etc. are all in support of that mission.

 

[kaladorn]

To my mind, on Imperial Navy ships, the following is true:

All flight personel, and perhaps all personel, wear G-sleeves beneath their TL-14 tailored vacc suits. The G-sleeve provides a better ability to withstand positive and negative gees in case the compensators kick out. The Vacc suit is worn (in some ship states) with the helmet and gloves off, in others, fully rigged and on internal support. Most workstations include a 'ship feed' of life support air etc. so prolonged vacc suit use is practical, only going to internal supply when damage or the need to move about the ship defeats this system. Due to the risks of moving about when you might expeience compensator failures, most of the people moving about once the ship is engaged would either be in DC suits or marines in BD. They have the advantage that if a comp kicks out in the middle of a manouver, they're much more likely to withstand the consequences (having been designed for rough atmospheric entry, among other things...).

I assume most areas of the ship have vacc suit lockers as well as rescue balls (in the event their is an immediate need to get inside a pressurized container).

Also, IMTU, no Marine would graduate to being aboard ship without having a level of BD or Vacc Suit (above 0!) and they'd have to have (actually, so would any shipboard person) at least Zero G Env-0.

 

[TheDS]

Even if flooding isn't a major concern, it has a counterpart, which is spacing. You don't want holes in your hull sucking out all your air; you've only got so much of it. I suppose it can be lower on the priority level than flooding is, since vacuum itself isn't going to hurt a lot of stuff.

The DCO (Damage COntrol Officer) is responsible to the ChEng (Chief Engineer), and may actually BE him on smaller ships. DC's, when they aren't busy repairing the ship, work with the HT's (Hull Techs) and maintain the hull. They may be called on to modify some bulkhead somewhere, or ensure the good repair of the DC equipment. Most of that stuff runs on batteries, and it's a real PITA when they run out. Firefighter hats with the lights on them are the worst; it's so easy to leave those stupid lights on, and they run down in a couple hours.

I would have to hope that some of the stupidity that is our DC equipment will have been unfutzed in the future. There is no technological reason why we have crap, only financial and political reasons. Emergency lighting systems that cannot recharge themselves and require monthly examination to ensure the batteries didn't run down, fire hoses susceptible to corrosion, which you have to scrape off, and can't put anti-corrosive on them, never mind REQUIRING special tools to hook hoses together and to the firemain... what if you don't have those tools?

I think you're right, in that restoring movement is the most important job. Movement is life in combat. Sitting ducks don't last long. I also think that critical systems should have local power sources. There is no reason not to have batteries sprinkled about the ship in a liberal fashion. No need for the emergency power conduit, which has to be set up manually. No need to have multiple power paths either. Just set up some batteries, give them an hour or two or charge, and when the main power goes out, the guns still fire, the sensors still see, the lights are still on. These batteries are rechargeable, and always hooked into main power, kind of like a UPS system. No interruption of power (but the beeping is going to annoy you ).

I seriously doubt that ships' crews are going to be running around in G-sleeves all the time. That would be like us wearing our chem-suits all the time. It just isn't done without good reason. Regarding chemical attack, we have different levels of readiness. I forget exactly what they are, but they are increasing levels of readiness, and take correspondingly less time to prepare for chem attack. All the way from simply having a gas mask on your hip to wearing the full suit and mask.

Life on a space cruiser will probably be similar. Most of the time, when you're not expecting problems, atmospheric pressure is normal, and no one carries their Vacc gear (Condition Green). Increase the level of readiness, and people may put on a G-sleeve or light vacc suit, and carry around a collapsible helmet and 10 minute air supply (Blue Alert). Increase it another level and the DC lockers are manned, including some people in full vacc suits (Yellow Alert).

Increase it to battle stations (Red Alert), and everyone goes to their assigned battlestation, securing the ship as they go. This includes sealing all hatches, depressurizing most or all of the ship, keeping people out of the p-ways except those responding to problems, and so on. A ship should be able to be completely ready for battle inside 15 minutes. Most aim for 10, but it takes a LOT of practice to get to it and keep it there. Weapons are already manned, and could be delivering fire long before the ship is completely battle-ready.

(If you haven't guessed, I was a squid as well, and you'd never know by my rate that I did a bunch of DC work my first couple years. Guess what that rate was.)

 

[Drakon]

Basically, you save the ship first. The crew comes second, sorta.

If you lose the ship you lose all the crew. Whereas if it a choice between crewman Smith and the rest of the ship, well, it sucks to be Smith. But if losing Smith means saving everyone else, simple math means you lose Smith.

 

[Drakon]

I have to disagree with the asertion of "no mulitple power paths" I come from the submarine Navy, and can sympathize and confirm some of the previous poster's complaints about DC gear and such. But on this one, I have to argue.

The electrical system of a ship should be redundant. You should have multiple feeds and switching systems so that if Generator 1 goes out of action, then all the systems it was feeding can be supplied from Generator 2. For naval and any vessel likely to see combat, this is essential for survival.

Redundancy, reliability and redundancy. That's the Navy way. And it is like that for a reason, it keeps folks alive at sea, or in space.

Local generators and a lot of batteries, I am all for. But for some big equipment that is not an option.

Also when it comes to ship design, more space-tight bulkheads are better, along with fewer penetrations through those bulkheads. You will also want to distribute your life support systems as well.

 

[jappel]

Great topic, great discussion and fascinating input from some knowledgable folks!

One point that was alluded to earlier that I think warrants some further discussion: fuel leaks / ruptured fuel tanks. If it's simply venting to vacumm then the problem is hopefully limited to just losing fuel, but if you've got atmosphere inside still a quantity of liquid hydrogen is going to cause problems. How would one best deal with that?

John

 

[kaladorn]

Some good thoughts....

1) Spacing (Venting): I'd call this a concern, but after the concerns about saving the ship. It's a long term threat, not a short term one. So it goes somewhere around 4 or 5 on my list of DC priorities.

2) DC Equipment: *Anyone* can have poorly designed equipment. Like the DC exoskeleton that won't fit through one particular hatch config, or the fusion cutter whose fuel cells don't mate with the standard fuel transfer systems, etc. This will still exist in 3I.

3) Pressure Bulkheads: Yes, these should appear regularly on well designed ships, war or otherwise. They serve to limit the scope of a catastrophe. Oddly, I was just thinking on the way home from town today about the through-bulkhead issue and how you'd want to minimize those and how this could limit the number of places air, fuel, power, data and human carrying doors existed. For each extra point of penetration, you run the risk of failure during a crisis and hence the failing (overall) of the bulkhead (in terms of airtightness, if not the structural support aspects).

4) Conditions aboard ship: I've done some calcs using some engineering stuff - You can, depending on the size of a hole, depressurize a bridge on a free trader in about 12 seconds to about 10 minutes.... 12 seconds won't let you get a vacc suit on. 30 seconds might, if you had it nearby. You've probably got 10-20 seconds after the critical threshold of staying concious. So, you'd want your duty crew to be in vacc suits (bridge watch, etc) even if they were not sealed.

As to G-sleeves, this is a debatable point. I assume all marines wear this under BD. I futher assume all pilots at the very least wear this. But since the entire ship can manouver at 6G in some cases, it makes *everyone* equivalent of modern aircrew, rather than Navy (Imagine if the Enterprise CVN could manouver like the fighters it launches! The Navy would look a lot different, methinks).

5) Local batteries - this would probably be good for lights, grav plates, heat, comms, computers. Maybe even mechanicals like hatches, etc. But I doubt you're going to distribute enough battery power to supply offensive ordinance (missile turrets you might manage), defenseive energy ordinance, screens, dampers, or engines. These types of items will require Plant Power. And you may have multiple plants (most people don't, but I think you can design a ship with multiple smaller plants in theory, at the loss of efficiency gained by large sizing plants). And even with redundant power linkages, having an emergency method of laying power to a system seems wise. Remember, even with local battery power, damage can take out those batteries.

 

[Drakon]

As for issue 3) this is pretty well understood, even in this day and age. You'd be surprised how many bulkhead penetrations go through a standard submarine. Yes, you are right, you want to keep these minimized, obviously. But for pressure concerns these are not that big a deal even with our primitive technology.

As for 5) I say dump the equipment that needs batteries unless absolutely necessary. Automated hatches? Leave them groundside. Use old fashion mechanical, arm activated hatches, with possible hydraulic sealing where absolutely needed. Communications? Go with sound powered phones.

Keep the tech level as low and using the least amount of power as absolutely necessary. Its cheap, its old, it ain't sexy, but it ain't gonna die on you when you really need it.

 

[flykiller]

Keep the tech level as low and using the least amount of power as absolutely necessary. Its cheap, its old, it ain't sexy, but it ain't gonna die on you when you really need it.

low tech level gear is not necessarily more reliable than high tech gear. it is, however, usually more easily repaired, whereas high tech gear frequently is only replaceable.