BattleTech - The Board Game of Armored Combat

BattleTech Game Systems => Ground Combat => Topic started by: deathfrombeyond on 30 June 2019, 14:37:17

Title: Maintenance of weapons
Post by: deathfrombeyond on 30 June 2019, 14:37:17
Players generally prefer laser weapons over ballistics weapons because there’s no ammunition to worry about with energy weapons. Most of the time, Battletech rules only cover the cost of purchasing equipment, but rarely goes into the c bill cost of maintaining equipment.

What do you think are the costs to maintain an energy based weapon over a missile based weapon? Energy vs ballistic?
Title: Re: Maintenance of weapons
Post by: Nastyogre on 30 June 2019, 16:06:11
I would guess that power lines, cooling systems lenses etc need maintenance for lasers. Plasma chambers, power feeds, cooling for PPC's etc. So that there is probably a significant amount of cost to maintain them. Perhaps not so much for an individual battle, but during a campaign probably.

I understand "real life" has little meaning in Btech, often anyway. But think of modern weapons. The more precise and advanced the weapon, the more care it requires. Fighter jets require constant maintenance. Tanks, quite a bit. Even a M4 carbine requires cleaning and lubrication.

Compare those to simpler weapons like AK's and mortars, the more advanced weapon requires more care. It might not be an actual cost from a materials standpoint. Gun oil and materials are much cheaper than the ammunition. It is probably more a matter of time to check things and such.

The lore states that items ammo for LRMS and SRMS is relatively advanced and expensive and is a limiter for some units and smaller realms. They don't really say that about Autocannons. IIRC (I don't have my books handy) the tech level of Autocannons is lower than for other weapons. So an energy based unit has to have access to the maintenance equipment. Fighting on a backwater planet or if you don't have access to the warehouses and factories of a world, I could see where all those lasers begin to have problems on a long campaign without supply. A laser that has been knocked out of focus or that has burned up their power cable is not much use against a "weak" AC 5 that just needs to be loaded and cleaned occasionally.

A campaign system should probably account for the time and cost of maintenance for more advanced weaponry.


Title: Re: Maintenance of weapons
Post by: Daryk on 30 June 2019, 16:15:54
Campaign Ops (page 24) throws that under "Spare Parts", and it's based on the unit the weapons are installed in.
Title: Re: Maintenance of weapons
Post by: dgorsman on 30 June 2019, 16:50:58
That should come in when using the detailed maintenance and repair rules, with lasers and PPCs being higher tech level have a higher penalty than ballistic weapons.  But you don't see that unless you get down to the AccounTech level.

Also, having more slots should make the ballistic weapons less likely to be completely destroyed.
Title: Re: Maintenance of weapons
Post by: Maelwys on 30 June 2019, 16:56:23
Its kind of debatable if there would be much difference in the way of maintenance costs for most weapons. Sure, there would be a little bit for fluff perhaps, but most "modern" BT weapons are tech E or F, and I'd expect any real difference in maintenance costs to be because of their level of technology, rather than what they are (Ballistic, missile, etc).

On the other hand, I just happen to have ATOW open today, working on a random character, and just came across the page with maintenance kits, and for small arms atleast, the Energy Weapon kit costs 850 c-bills and has a restocking fee of 160, while the slug thrower maintenance kit has a c-bill cost of 100, with a restocking fee of 20.

So energy weapons might require more expensive tools to work with. On the other hand, the large scale repair kits only has a "Weapon" repair kit, and isn't broken down by type.
Title: Re: Maintenance of weapons
Post by: AdmiralObvious on 30 June 2019, 19:59:26
There's a lot of factors that probably would go into this, especially depending on how many rules you tie into the mix, and how much margin of error there is.

Autocannons are probably going to be easier to maintain, but it's ultimately going to depend on who manufactured the gun itself. The autoloader, at least in the real world is an extremely finicky and sensitive piece of equipment, you break that and you basically have to replace the whole gun.

Lasers on the other hand are probably more complex to actually put together, I can actually see them as a relatively low maintenance type of weapon, assuming your parts are of any good quality. With lasers, you just have to make sure the mirrors and lenses focus properly, and then plug it in. Once you get into actually taking them apart and putting them back together though, that's probably when the price is going to go up significantly.

My opinion is that Autocannons will need more frequent maintenance, especially if they've been used a lot. Lasers will tend to need the same level of maintenance, regardless of how much they are used, and will only really need to be disassembled if something goes wrong.

It's also worth noting that if something goes wrong with an Autocannon, odds are that something is going to go REALLY wrong. Lasers, unless stupidly designed (like the Hyper Laser) will generally not want to blow up on you, they'll just heat up.
Title: Re: Maintenance of weapons
Post by: Orin J. on 30 June 2019, 21:14:51
energy vs ballistics mantainance i would assume is a matter of if you want to pay in small chunks or large ones. ballistics need fairly consistent "Day-to-day" work to maintain them, while the more fragile parts of energy weapons like lasers and particle projectors would be in sealed vacuum components for maximized efficiency so all those would be is checking the mountings and seals for the most part.

of course when those sealed parts do go, you're replacing a much more expensive component (or if you're truly boned on materials, trying to build a clean room to reseal them- don't fancy that) than you are if you were forced to replace parts of the autocannon, which you might even be able to hand-machine yourself with the right worktable.

but then there's the mangnetic acceleration coils of a gauss rifle....just running diagnostics on those might be a serious hassle, especially if you don't trust any internal diagnostics- i doubt there's any built-in diagnostics computer that could withstand the kind of EM-field those coils must be working under, which might mean you need to open the entire gun to connect testing feeds to check for a fault that will blow out the capacitors- which might cause the gauss round to fly right through the side of the gauss rifle.

in the end, i'm guessing the biggest cost is ongoing training of technical staff as it seems like most groups replace the different models of their weapons like they're identical just because they meet the same performance specs. senior techs might be better force commanders than the 'mechjocks they service!
Title: Re: Maintenance of weapons
Post by: deathfrombeyond on 01 July 2019, 03:06:11
So I’ve heard a lot about energy versus ballistics...what about energy versus missiles?
Title: Re: Maintenance of weapons
Post by: Apocal on 01 July 2019, 05:24:24
So I’ve heard a lot about energy versus ballistics...what about energy versus missiles?

I worked on missiles in real life. Most missiles are wooden rounds (i.e. sealed, with no maintenance requirements once issued) and I'd assume this trend continued into the 31st century because it just makes sense. Mounts and launchers can have serious maintenance requirements, but they shouldn't be eating parts or going through loads of consumables much, so all you're looking at is the tech's time, not an actual expenditures. You might have a big DC motor to give it some play or what have you, but its mostly just dealing with shock's effect on wiring and connectors that cause actual issues. And on the newer stuff, with fibers, even most of that goes away.

So missiles should be next to nothing maintenance-wise.

I technically worked on lasers as well but  not in anything comparable to BT. For what it is worth though, everything laser, except lens/alignment stuff, was pop-and-swap with extremely minimal maintenance required.

I will say that fifteen minutes of tech-time to load out a bin of autocannon ammo in the field with minimal support equipment is quite impressive, regardless of maintenance costs.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 01 July 2019, 12:40:04
I worked on missiles in real life. Most missiles are wooden rounds (i.e. sealed, with no maintenance requirements once issued) and I'd assume this trend continued into the 31st century because it just makes sense. Mounts and launchers can have serious maintenance requirements, but they shouldn't be eating parts or going through loads of consumables much, so all you're looking at is the tech's time, not an actual expenditures. You might have a big DC motor to give it some play or what have you, but its mostly just dealing with shock's effect on wiring and connectors that cause actual issues. And on the newer stuff, with fibers, even most of that goes away.

So missiles should be next to nothing maintenance-wise.

I technically worked on lasers as well but  not in anything comparable to BT. For what it is worth though, everything laser, except lens/alignment stuff, was pop-and-swap with extremely minimal maintenance required.

I will say that fifteen minutes of tech-time to load out a bin of autocannon ammo in the field with minimal support equipment is quite impressive, regardless of maintenance costs.
One big difference between IRL and Btech is that their missile reuse the same launch tubes, over and over again.  All that exhaust can't be good for the tubes and the ammo feed system.
Title: Re: Maintenance of weapons
Post by: Kovax on 01 July 2019, 12:53:14
The real cost of maintaining large cannons would probably out-strip that of maintaining a laser, because friction of the rounds against the rifling grooves or barrel walls WILL wear the gun out, and it WILL need to be either re-lined or replaced.  Most of the old battleships were only good for a few hundred rounds per barrel before requiring gun replacement.  The old railroad cars with the enormous siege guns used in WWI and WWII had individually numbered rounds that had to be fired in order, because each one was a few mills larger than the previous to account for barrel wear and expansion due to stress.

Lasers would be more likely to burn or char certain components over time, like power feeds, lenses, and capacitor banks.  The enormous amounts of energy passing through them for split-seconds would create incredible stresses and temperatures for those brief moments, and would almost inevitably cause long-term degradation.  That would likely result in frequent replacement of such components, as opposed to the massive occasional cost of barrel replacement for a ballistic weapon.

Things get really funky when you start pushing the envelope on materials.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 01 July 2019, 15:23:27
On the other hand, I just happen to have ATOW open today, working on a random character, and just came across the page with maintenance kits, and for small arms atleast, the Energy Weapon kit costs 850 c-bills and has a restocking fee of 160, while the slug thrower maintenance kit has a c-bill cost of 100, with a restocking fee of 20.

So energy weapons might require more expensive tools to work with. On the other hand, the large scale repair kits only has a "Weapon" repair kit, and isn't broken down by type.

Yeah, that is probably going to come down to things like power-meters and other calibration items for energy based small arms.  Restocking a slug thrower is buying cleaner, oil, q-tips and patches . . . and stealing "that guy's" in the platoon's toothbrush for scrubbing to pass around among everyone else.  Mech techs (or armor) are already going to have the electronics tools as part of their basic kit to  work on mechs.

I think it will come down to . . . guns are going to require frequent small amounts of maintenance (make sure the timing & head spacing on that MG is right once a week/month) as well as inspecting ammo, energy weapons are going to be low/no maintenance for most of their service life but will be lots of time required WHEN work is needed along with impact/shock alignment calibration (did the lens get knocked at all loose?), while missiles are going to be sort of similar to guns EXCEPT there will not be bores & breaches to clean with the rounds typically sealed up to fire (see MLRS pods).  Guns & Missiles both leave behind heat, toxic gases, pressure waves, residue, and other effects like jammed brass or missiles hung on rails.

IMO, costs year to year are going to be the same- for all the gun barrels you are replacing you will also have to replace lenses, lasing chambers, and other energy components that will get burned out.
Title: Re: Maintenance of weapons
Post by: Mohammed As`Zaman Bey on 01 July 2019, 18:23:27
 Costs and maintenance are handled by assigning tech/hours, etc. Wear and tear is based on the tech rolls...or failed rolls. 
Title: Re: Maintenance of weapons
Post by: Caedis Animus on 01 July 2019, 22:52:56
Yeah, that is probably going to come down to things like power-meters and other calibration items for energy based small arms.  Restocking a slug thrower is buying cleaner, oil, q-tips and patches . . . and stealing "that guy's" in the platoon's toothbrush for scrubbing to pass around among everyone else.  Mech techs (or armor) are already going to have the electronics tools as part of their basic kit to  work on mechs.

I think it will come down to . . . guns are going to require frequent small amounts of maintenance (make sure the timing & head spacing on that MG is right once a week/month) as well as inspecting ammo, energy weapons are going to be low/no maintenance for most of their service life but will be lots of time required WHEN work is needed along with impact/shock alignment calibration (did the lens get knocked at all loose?), while missiles are going to be sort of similar to guns EXCEPT there will not be bores & breaches to clean with the rounds typically sealed up to fire (see MLRS pods).  Guns & Missiles both leave behind heat, toxic gases, pressure waves, residue, and other effects like jammed brass or missiles hung on rails.

IMO, costs year to year are going to be the same- for all the gun barrels you are replacing you will also have to replace lenses, lasing chambers, and other energy components that will get burned out.
Makes me think of exactly how many maintenance (Or otherwise) related failures could possibly occur in the third SW and more. You'd have to be insane to play with that many random-chance problems.

"Oh, looks like your thirteenth LRM tube hung onto the missile-roll to see if it explodes in the tube, putters out, or just slips out and drops. Oh, it puttered out? Roll to see if the computer caught the jam in time." or "Your Medium Laser's lense cracked. Roll to see how badly it brok-oh, it now does small laser damage at 0 hex range with a +5 to hit. Oh, that sucks."
Title: Re: Maintenance of weapons
Post by: AdmiralObvious on 02 July 2019, 01:01:42
Makes me think of exactly how many maintenance (Or otherwise) related failures could possibly occur in the third SW and more. You'd have to be insane to play with that many random-chance problems.

"Oh, looks like your thirteenth LRM tube hung onto the missile-roll to see if it explodes in the tube, putters out, or just slips out and drops. Oh, it puttered out? Roll to see if the computer caught the jam in time." or "Your Medium Laser's lense cracked. Roll to see how badly it brok-oh, it now does small laser damage at 0 hex range with a +5 to hit. Oh, that sucks."
I mean during the SW, eventually the quality of basically everything you've got left is going to be next to none. You're probably essentially replacing laser optics with poor quality glass by the time of round three, unless you were lucky enough, and savvy enough to keep a rather significant cache of supplies around "just in case".
Title: Re: Maintenance of weapons
Post by: Apocal on 02 July 2019, 03:24:54
One big difference between IRL and Btech is that their missile reuse the same launch tubes, over and over again.  All that exhaust can't be good for the tubes and the ammo feed system.

IRL missiles can reuse the same tubes (or cells) again and again. Launching doesn't do that much, if anything: wipe clean and it is fine. You don't even really need to wipe clean, as long as the rail/launcher interface is fine. Now, if you're talking about the more exotic liquid propellant or something, I wouldn't know. But those are (were) mostly huge missiles with ranges of dozens or hundreds of miles.

I mean during the SW, eventually the quality of basically everything you've got left is going to be next to none. You're probably essentially replacing laser optics with poor quality glass by the time of round three, unless you were lucky enough, and savvy enough to keep a rather significant cache of supplies around "just in case".

Lasers are incredibly sensitive to that sort of thing. There isn't much "play" between 'fine', 'mostly fine' and 'this thing don't work.' I imagine what tech did survive the Succession Wars would be a whole lot of pop-and-swap assemblies, made by lights-out factories, that techs aren't forced to spend much time worrying over. All the bespoke stuff should be gone.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 02 July 2019, 09:26:23
IRL missiles can reuse the same tubes (or cells) again and again. Launching doesn't do that much, if anything: wipe clean and it is fine. You don't even really need to wipe clean, as long as the rail/launcher interface is fine. Now, if you're talking about the more exotic liquid propellant or something, I wouldn't know. But those are (were) mostly huge missiles with ranges of dozens or hundreds of miles.

The rails maybe fine for mounting the tube/cell, but that exhaust is still going to deposit residue along with the heat.

(https://images04.military.com/sites/default/files/media/equipment/weapons/m270-multiple-launch-rocket-system-mlrs/2014/02/m270-mlrs-005.jpg)

Where you can see bare metal is where they ground off the residue from the latest live fire in the motorpool . . . and you can also see the previous green paint before everything ended up tan.  A little bit of the top, but all of the bottom of the launcher has to be ground off.  They do check the rails and sometimes have to grind inside the SPLL to remove residue.  Launcher is probably at least 15 years old in this picture since I see the ACUs in the background, which means it went through at least one qualifying live fire a year and may have participated in Desert Storm for lots of firing.

(http://2.bp.blogspot.com/-9ptvpAwWEPE/UELuys5WTzI/AAAAAAAAWIc/vpOy8I_VylA/s400/Rocket42b.JPG)
You can even see the discoloration on one that made it on TV with everyone's favorite Marine (sniff sniff) with what is probably dummy pods loaded- basically fired pods that have some concrete in them for weight & balance to reflect live pods and a sim panel.  The rockets are solid propellant based which IIRC matches BTU description.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 02 July 2019, 11:28:39
Lasers are incredibly sensitive to that sort of thing. There isn't much "play" between 'fine', 'mostly fine' and 'this thing don't work.' I imagine what tech did survive the Succession Wars would be a whole lot of pop-and-swap assemblies, made by lights-out factories, that techs aren't forced to spend much time worrying over. All the bespoke stuff should be gone.
We're on the same page, I think.
If a laser is designed with battlefield maintenance in mind, it should be require relatively minimal labor time for a lot of failures.  Granted I'm picturing a "medium laser on a bench," scenario.  Getting to the CT mlas on an old Zeus must have been a pain. Most subsystems should be a self contained module, that can be yanked, replaced and diagnosed on the bench. And given the amount electronics required to make a laser work, it would be pretty easy to build in diagnostics.  Put a thermocouple on the frame of every optical element, and you can get a lot of useful data.  "Hmmm, temperature warning from the 3rd stage focusing assembly.  Temperature during firing is spiking 34% above normal.  Looks like it started at 13:44:19...  What did that damn mechjock do to my mech at 13:43?" 

Depending on the tolerances and how well the system was designed, made, adjusting the focusing elements could either be relatively painless or a brutal misery, with little middle ground. I've done work like this, and it's either a breeze or it will drive you to drink.
Title: Re: Maintenance of weapons
Post by: deathfrombeyond on 03 July 2019, 01:57:25
IMO, costs year to year are going to be the same- for all the gun barrels you are replacing you will also have to replace lenses, lasing chambers, and other energy components that will get burned out.

Maybe I'm misunderstanding this statement, but I have a hard time believing that the maintenance costs for an autocannon is going to be the same, over time, as a laser.
Title: Re: Maintenance of weapons
Post by: RifleMech on 03 July 2019, 03:12:30
Maybe I'm misunderstanding this statement, but I have a hard time believing that the maintenance costs for an autocannon is going to be the same, over time, as a laser.

It's like Autocannons are like older cars and Lasers are newer ones. Older cars go into the shop more than newer ones but when a new one does go into the shop it costs more to be fixed so the price ends up equaling out.
Title: Re: Maintenance of weapons
Post by: Apocal on 03 July 2019, 04:22:45
The rails maybe fine for mounting the tube/cell, but that exhaust is still going to deposit residue along with the heat.

Where you can see bare metal is where they ground off the residue from the latest live fire in the motorpool . . . and you can also see the previous green paint before everything ended up tan.  A little bit of the top, but all of the bottom of the launcher has to be ground off.  They do check the rails and sometimes have to grind inside the SPLL to remove residue.  Launcher is probably at least 15 years old in this picture since I see the ACUs in the background, which means it went through at least one qualifying live fire a year and may have participated in Desert Storm for lots of firing.

Oh, I wasn't saying the residue wasn't there. It just didn't impact the system's firing any. We cleaned it off, maybe touched up paint in spots where it had been too burned to come fully clean, as a long-term corrosion control measure. The rails and cell interiors handled launch(es) fine and obviously the missile itself was expended. It wasn't like gun maintenance where you're dealing with tight mechanical tolerances, being worried about whatever carbon or dirt actually gunking up the works and causing a malfunction.

Now actually reloading was where you would lose time, because that was just... ugh, nah.

Getting to the CT mlas on an old Zeus must have been a pain.

Imagine pulling the AC20 off an Atlas with nothing but the BTech equivalent of a hoist.
Title: Re: Maintenance of weapons
Post by: Col Toda on 03 July 2019, 07:34:14
What you get with ammo using weapons is short term throw weight of damage . With 10 Double Heat sinks you can flywheel an ER PPC and ER med laser . With the same 20 heat dissaption you get 2 Arrow IV launchers in an O Bakemono . For Inner Sphere tech quite literally double the damage and area effect .With C3 ; TAG ; and Veteran gunners will get you a horrific 12 -16 cimbat turns and if you do not kill outright most of the opposition Energy Boats in that time you lose the battle but even then may win the strategic war of attrition .

People will maintain whatever units that best represents theirown playing style.
Title: Re: Maintenance of weapons
Post by: dgorsman on 03 July 2019, 08:43:03
It's like Autocannons are like older cars and Lasers are newer ones. Older cars go into the shop more than newer ones but when a new one does go into the shop it costs more to be fixed so the price ends up equaling out.

An autocannon can be maintained with a sledgehammer, pair of pliers, and a welding torch.  Energy weapons, not so much.

Personally, I'm willing to wave off agressive barrel wear with a combination of advanced materials, low friction sabots, and so on.
Title: Re: Maintenance of weapons
Post by: Orin J. on 03 July 2019, 09:08:08
An autocannon can be maintained with a sledgehammer, pair of pliers, and a welding torch.  Energy weapons, not so much.

Personally, I'm willing to wave off agressive barrel wear with a combination of advanced materials, low friction sabots, and so on.

autocannons having barrel sleeves rather than being a single piece would be reasonable for them. the main matter if maintenance for them is probably cleaning, and i dunno how much that costs aside from astech man-hours and they can do that whenever there's nothing pressing.

also isn't the lasers on the Zeus fluffed as being built with fiberoptic cabling to make it more compact and easier to fit into that space on the torso?
Title: Re: Maintenance of weapons
Post by: Colt Ward on 03 July 2019, 10:15:37
It's like Autocannons are like older cars and Lasers are newer ones. Older cars go into the shop more than newer ones but when a new one does go into the shop it costs more to be fixed so the price ends up equaling out.

Pretty much that type of example . . .

I will use a Zeus as an example as the original mounts the basic mix . . . my tech is going to spend a hour a week inspecting and giving fresh lube to the breech/slide/action of my AC/5, swabbing the barrel, inspecting the loading mechanism, cycling the mechanisms (dry firing), or cleaning the ejection ports.  Once a month he will be checking the alignment for the laser's aiming mechanism (sort of like bore-sighting for a ballistic) with that test will take 4 hours for set up and function testing.  So while autocannons may require frequent work, its probably going to be small amounts of time- also by their nature they are a bit easier to work on; moving parts and magazine wells or breech areas with recoil has a lot of open space where you can get to their parts.  Energy weapons without moving parts are going to end up crammed in a space with just enough room for the  unit, so working on them might be harder- think of some of the more convoluted ways you had to replace headlights on a car, especially a modern car where they are shrinking & cramming everything in as small a space as possible.

PCMS has daily, weekly, monthly, semi-annual and annual tasks . . . so while a task may have to be performed once a week, its usually something short.  Tasks that are required once or twice a year tend to take longer- our annual task for the M1068s was a all day affair for the crews (1st level tech care) and had to be signed off on by the actual mechanics who gave your work a quick inspection.
Title: Re: Maintenance of weapons
Post by: massey on 03 July 2019, 13:53:59
My view of it will probably not align with whatever is in Campaign Operations or any of those other giant tomes.

I think coolant flushes are expensive, and an all-laser mech is going to need a lot more of those than a ballistic or missile mech.  There would be a reason why people build something besides energy boats, that reason just doesn't come up in standard Battletech gameplay a lot.

Autocannons are probably easier to build, easier to repair, and easier to maintain.  If your AC-5 gets hit with a crit, it won't work anymore, but depending on where that crit is, you might be able to repair it in a machine shop.  If your PPC gets critted, good luck.  That thing is a far more complex piece of machinery.  If nothing goes wrong, lasers are probably about the least maintenance intensive weapons you can have.  But if it gets broken, it's trash.  And if you try to operate without any maintenance, your coolant is going to get less and less effective.  This isn't something you'd notice over a handful of games, but you would notice in a long campaign.

You need techs anyway, so a lot of maintenance work on ACs or missile launchers would get done during their downtime.  They aren't always repairing battle damage.  Your costs aren't going to go up appreciably just because the guy has to change the oil and check the headlight fluid.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 03 July 2019, 16:14:19
My view of it will probably not align with whatever is in Campaign Operations or any of those other giant tomes.

I think coolant flushes are expensive, and an all-laser mech is going to need a lot more of those than a ballistic or missile mech.  There would be a reason why people build something besides energy boats, that reason just doesn't come up in standard Battletech gameplay a lot.

That's a good point. 

Oh, I wasn't saying the residue wasn't there. It just didn't impact the system's firing any. We cleaned it off, maybe touched up paint in spots where it had been too burned to come fully clean, as a long-term corrosion control measure. The rails and cell interiors handled launch(es) fine and obviously the missile itself was expended. It wasn't like gun maintenance where you're dealing with tight mechanical tolerances, being worried about whatever carbon or dirt actually gunking up the works and causing a malfunction.

But Btech missiles are a lot like cannons, themselves.  There is a launch tube, that is loaded from the rear, or even the side  Even if each missile is in its own self contained cannister, you need some kind of sealing mechanism to keep the exhaust from going back into the feed system.  If the missiles are in self contained cannisters, you need to deal with the empties before you load the next one.  Then there's the feed mechanism and the magazine.  The closest analog I can think if is the  old Mk 26 (https://en.wikipedia.org/wiki/Mark_26_missile_launcher) missile launchers.
Title: Re: Maintenance of weapons
Post by: RifleMech on 04 July 2019, 17:47:50



Pretty much that type of example . . .

 :thumbsup: 

That was my thinking. They get more maintanance but it doesn't cost as much. Plus they're easier to repair. Energy weapons not so much.

Wouldn't energy weapons that have barrels need to have them checked for wear do to all the heat traveling though it? And wouldn't those without need to have the lenses cleaned, polished and alligined?


My view of it will probably not align with whatever is in Campaign Operations or any of those other giant tomes.

I think coolant flushes are expensive, and an all-laser mech is going to need a lot more of those than a ballistic or missile mech.  There would be a reason why people build something besides energy boats, that reason just doesn't come up in standard Battletech gameplay a lot.

Good point. Its something most mechs would need but energy boats more so. Especially if they're using DHS-Ps with the toxic chemicals. (Is that still a thing)
Title: Re: Maintenance of weapons
Post by: Colt Ward on 05 July 2019, 00:22:23
A laser 'barrel' IIRC should really be a vacuum tube so you do not get heat bloom or diffusion through particles.
Title: Re: Maintenance of weapons
Post by: Orin J. on 05 July 2019, 00:30:31
the point where the lens makes contact with air though, that's gonna need to be watched like a hawk, lens and seal holding it in place both. not to mention whatever is translating the juice from the fusion reactor into the right amps for the weapon is probably getting a heck of a workout being plugged into THAT. i'd assume that's part of the weapon and not the engine since an astech missing that part and plugging a weapon in naked only needs to happen ONCE before there's some serious changes made.
Title: Re: Maintenance of weapons
Post by: mbear on 05 July 2019, 10:06:55
But Btech missiles are a lot like cannons, themselves.  There is a launch tube, that is loaded from the rear, or even the side  Even if each missile is in its own self contained cannister, you need some kind of sealing mechanism to keep the exhaust from going back into the feed system.

That could easily be handled by having a U-shaped exhaust tube that directs the exhaust out the front of the launcher. Something like the plenum and uptake stack used by Mk 41 VLS. Here's a picture to show what I mean.
(https://www.dsiac.org/sites/default/files/uploads/VLS_Baselines2.jpg)
You would move the plenum and uptake into the individual missile container instead of the launcher itself. Then the canister is moved into place to launch out the "barrel" of the launcher.


If the missiles are in self contained cannisters, you need to deal with the empties before you load the next one.  Then there's the feed mechanism and the magazine.
Those are good points.

The empty canisters could self-destruct upon launch. I think there are some modern tank cannons that use consumable cases for storage. When fired, the propellant burns up most/all of the shell's packaging.

Or the missile canister could be squished by the next fully loaded missile cell dropping into place. (I do something similar with aluminum soda cans after I've drunk the contents. ;) )

Or maybe the canister is ejected from the launcher by using heated air from the 'Mech's heat sink system that's been compressed.
Title: Re: Maintenance of weapons
Post by: Apocal on 05 July 2019, 11:49:23
That's a good point. 

But Btech missiles are a lot like cannons, themselves.  There is a launch tube, that is loaded from the rear, or even the side  Even if each missile is in its own self contained cannister, you need some kind of sealing mechanism to keep the exhaust from going back into the feed system.  If the missiles are in self contained cannisters, you need to deal with the empties before you load the next one.  Then there's the feed mechanism and the magazine.  The closest analog I can think if is the  old Mk 26 (https://en.wikipedia.org/wiki/Mark_26_missile_launcher) missile launchers.

RE: exhaust in the feed system
Missiles can get blasted by their own exhaust gasses without issue, generally speaking. Like the Mk. 26 you posted; there is no protection for the second missile on the rail from the first's exhaust. The problem with allowing stuff like dirt to build up in an autocannon is there are fairy tight mechanical tolerances involved: if nothing else, you have the round engaging with the barrel and the case having to extract without snagging anything. A little too big (even from normal thermal expansion) and nothing works.

But there isn't really an equivalent for missiles because rails aren't that tight (IME) and are fairly tolerant of deviations because they have to be.

That isn't to say there aren't things that go wrong -- there absolutely are. It just isn't stuff like gasses causing them. Missile maintenance, would be more about the launcher's function, largely regularly checking its integrity and testing it, since there isn't a hard-and-fast function check like with a firearm or a cannon dry-fire. Especially with a Mech since you'd be dealing with routine and prolonged periods of shock (stomping around on hard-packed ground, landing on top of a building after jump jetting, generally getting banged around during fights). 



Title: Re: Maintenance of weapons
Post by: RifleMech on 06 July 2019, 20:20:35
A laser 'barrel' IIRC should really be a vacuum tube so you do not get heat bloom or diffusion through particles.

Wouldn't it need to be check to see if if its still sealed and nothing is warped from heat?
Title: Re: Maintenance of weapons
Post by: Orin J. on 06 July 2019, 21:10:08
i doubt a pressure sensor that'd pick up if the pressure inside of the firing chamber is still correct would be hard to incorporate, and that'd relegate it to a diagnostics check rather than needing a teardown.
Title: Re: Maintenance of weapons
Post by: The_Caveman on 06 July 2019, 21:44:57
The real cost of maintaining large cannons would probably out-strip that of maintaining a laser, because friction of the rounds against the rifling grooves or barrel walls WILL wear the gun out, and it WILL need to be either re-lined or replaced.  Most of the old battleships were only good for a few hundred rounds per barrel before requiring gun replacement.  The old railroad cars with the enormous siege guns used in WWI and WWII had individually numbered rounds that had to be fired in order, because each one was a few mills larger than the previous to account for barrel wear and expansion due to stress.

I don't think you'd have a conventional barrel construction in an autocannon. The combination of rate-of-fire and projectile caliber with repeat followup shots are just too damaging. There are current-day medium caliber naval guns capable of burst fire in the 120 RPM range and after firing a few dozen shells they need to cool for half an hour or more. Even with better materials, such a weapon would wear out far too quickly if required to fire hundreds of shots per hour like a 'Mech autocannon in a pitched battle.

More likely I think you'd have the gun constructed as a sleeve-and-liner system where most of the structural strength comes from a fixed outer sleeve that is fitted with a network of coolant channels. This would be a low-wear part whose main job would be dissipating heat and containing the hoop stresses on the inner liner. The removable liner would be a "dumb" metal pipe made out of a high-wearing steel (or in fancy models even a ceramic) and fitted with a quick-change mechanism so techs could slide them out and pop in a new one every few hundred rounds without the need to rip out the entire cannon and disassemble it.

Because the inner liner is a sacrificial part, it could be a lot thinner and possibly light enough for a vehicle crew to do the change on their own for the AC/2 and AC/5 in the field. And because most of the barrel's stiffness comes from the outer sleeve, replacing a liner wouldn't severely alter the barrel harmonics. You'd just have to run a handful of practice shells through the gun to verify the point of aim and you'd be good to go.

With a system like that in place, cannon maintenance wouldn't be enormously expensive. Spent metal liners could even be recycled, by re-forging the tube in a hydraulic mandrel until the inner diameter was correct and friction-welding copper or aluminum sheet to the outside as a thermal shim (and re-cutting rifling, though I suspect nearly all ACs are smoothbores due to ammunition preference).
Title: Re: Maintenance of weapons
Post by: RifleMech on 06 July 2019, 22:50:49
i doubt a pressure sensor that'd pick up if the pressure inside of the firing chamber is still correct would be hard to incorporate, and that'd relegate it to a diagnostics check rather than needing a teardown.

Probably but sensors go bad.


I don't think you'd have a conventional barrel construction in an autocannon. The combination of rate-of-fire and projectile caliber with repeat followup shots are just too damaging. There are current-day medium caliber naval guns capable of burst fire in the 120 RPM range and after firing a few dozen shells they need to cool for half an hour or more. Even with better materials, such a weapon would wear out far too quickly if required to fire hundreds of shots per hour like a 'Mech autocannon in a pitched battle.

More likely I think you'd have the gun constructed as a sleeve-and-liner system where most of the structural strength comes from a fixed outer sleeve that is fitted with a network of coolant channels. This would be a low-wear part whose main job would be dissipating heat and containing the hoop stresses on the inner liner. The removable liner would be a "dumb" metal pipe made out of a high-wearing steel (or in fancy models even a ceramic) and fitted with a quick-change mechanism so techs could slide them out and pop in a new one every few hundred rounds without the need to rip out the entire cannon and disassemble it.

Because the inner liner is a sacrificial part, it could be a lot thinner and possibly light enough for a vehicle crew to do the change on their own for the AC/2 and AC/5 in the field. And because most of the barrel's stiffness comes from the outer sleeve, replacing a liner wouldn't severely alter the barrel harmonics. You'd just have to run a handful of practice shells through the gun to verify the point of aim and you'd be good to go.

With a system like that in place, cannon maintenance wouldn't be enormously expensive. Spent metal liners could even be recycled, by re-forging the tube in a hydraulic mandrel until the inner diameter was correct and friction-welding copper or aluminum sheet to the outside as a thermal shim (and re-cutting rifling, though I suspect nearly all ACs are smoothbores due to ammunition preference).


Built in cooling, along with stronger recoil and ammo feed systems, would help explain why Autocannons are so much heavier than Rifle Cannons.
Title: Re: Maintenance of weapons
Post by: SCC on 07 July 2019, 04:54:08
Built in cooling, along with stronger recoil and ammo feed systems, would help explain why Autocannons are so much heavier than Rifle Cannons.
Autocannons are so heavy because Battledriods was pretty much bad by a bunch of guys in a garage without any thought to balance.
Title: Re: Maintenance of weapons
Post by: Daryk on 07 July 2019, 06:26:51
Naval weapons, at least, have barrel lives in the thousands of rounds: http://www.navweaps.com/Weapons/WNUS_5-62_mk45.php
Title: Re: Maintenance of weapons
Post by: Apocal on 07 July 2019, 06:43:48
Naval weapons, at least, have barrel lives in the thousands of rounds: http://www.navweaps.com/Weapons/WNUS_5-62_mk45.php

That's a modern and relatively low-powered weapon. Kovax was referring specifically to old battleships and NavWeaps has the old Mk7 16" with a barrel life of 290-350 rounds. Other battleship guns are in the same ballpark.
Title: Re: Maintenance of weapons
Post by: Daryk on 07 July 2019, 07:12:59
The muzzle energy of the ERGM isn't exactly low power ("only" half of a rail gun), and still has a barrel life in the thousands of rounds (1,500 to 3,000; see footnote 7a under ammunition).  And 127mm is a bit more in the realm of what a 'mech would mount.  Hilarious art aside, no 'mech is walking around with a 406mm cannon.
Title: Re: Maintenance of weapons
Post by: Caedis Animus on 07 July 2019, 09:04:52
I think the highest caliber on any known AC-20 toting unit in Battletech is a 200-to-210mm Ultra AC on some Clan Omnimech, either the Summoner or the Ebon Jaguar.
Title: Re: Maintenance of weapons
Post by: Daryk on 07 July 2019, 09:06:37
Agreed, that's what I remember too.
Title: Re: Maintenance of weapons
Post by: The_Caveman on 07 July 2019, 12:28:53
The muzzle energy of the ERGM isn't exactly low power ("only" half of a rail gun), and still has a barrel life in the thousands of rounds (1,500 to 3,000; see footnote 7a under ammunition).  And 127mm is a bit more in the realm of what a 'mech would mount.  Hilarious art aside, no 'mech is walking around with a 406mm cannon.

Much lower rates of fire than 'Mech autocannons though.

The Mk45 gun tops out at 20 RPM. Based on shell weight, an AC/5 of similar bore diameter is shooting 3-round bursts. Since regular ACs put all the shells on the same location and Ultras in double-rate mode don't (as well as the TacOps rapid-fire ACs rule and the old Solaris rule permitting a full-power shot every 2.5 seconds at a significant heat penalty), it is strongly implied that the time of a burst is very short. Probably upwards of 120 RPM for the cyclic rate.

Faster rates of fire accelerate barrel wear as the barrel has less time to cool between projectiles and prolonged exposure to corrosive propellant gases. It would only get worse for the bigger ACs (the AC/20 producing as much heat as a large laser does not make me optimistic for its barrel life).
Title: Re: Maintenance of weapons
Post by: Daryk on 07 July 2019, 14:59:33
Based on shell weight, I think an AC/5 with a similar bore would be firing single rounds (or two at the most), with the extra weight going to propellant.
Title: Re: Maintenance of weapons
Post by: Orin J. on 07 July 2019, 16:38:53
we aren't trying to untie the gordian knot of how battletech ammo works, we're talking about maintenance. and it's not like we have a set bore for a given AC size, anyways. best to work with an average there i'd think....

i doubt a pressure sensor that'd pick up if the pressure inside of the firing chamber is still correct would be hard to incorporate, and that'd relegate it to a diagnostics check rather than needing a teardown.

Probably but sensors go bad.

and the diagnostics would pick that up too, what's the point here?
Title: Re: Maintenance of weapons
Post by: The_Caveman on 07 July 2019, 16:56:53
Based on shell weight, I think an AC/5 with a similar bore would be firing single rounds (or two at the most), with the extra weight going to propellant.

A volley of AC/5 is somewhere in the neighborhood of 50kg. Complete rounds for 5-inch class guns are 15-25kg. They're not loading upwards of 30kg of propellant behind the shell, there would be no point. You can't propel a projectile faster than the combustion speed of the propellant, no matter how much of it you use, and physics restrains most chemical propellants to 2000-3000 m/s--hence why hydrogen/helium light gas guns are used for micrometeoroid simulations.

Besides, if ACs are single-shot weapons, there is nothing significant to differentiate them from the primitive rifle cannon. If the answer is propellant or projectile, that can be easily retrofitted to the older designs. A large-bore burst-fire weapon is the most convenient explanation for the ways ACs behave relative to everything else. Anything else requires lots of handwavium or mental gymnastics to justify.
Title: Re: Maintenance of weapons
Post by: Daryk on 07 July 2019, 17:13:44
We're definitely looking at different tables.  The ERGM by itself is 50kg, and the lightest shell I see on the page I linked is 29kg.  Propellant charges run from 8.3kg to 18.6kg.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 07 July 2019, 18:18:19
And you have no idea how that weight could be distributed . . . heck, you could have a flush of some noble gas as part of firing the AC which would factor into the 'weight' per shot.

IMO you are really trying to dig down into the weeds since are are told Autocannon classes are done by size- not how many shells are fired, how often or their weight.  So some descriptions in the past for AC/5s made them sound like RACs currently are- a spinning gatling barrel shooting out smaller rounds- and I want to say we have a description of one huge bore single shot, and everything in between which all depends on the model.

The most you can break down on a AC is that they have a barrel, a breech, a firing mechanism, and a recoil absorbing shock system to put it back in battery along with mechanisms to aim.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 08 July 2019, 11:35:53
i doubt a pressure sensor that'd pick up if the pressure inside of the firing chamber is still correct would be hard to incorporate, and that'd relegate it to a diagnostics check rather than needing a teardown.
Temperature sensors would be my go-to.  Thermocouples are very rugged, and just about anything that misbehaves will probably start by overheating a bit.


Probably but sensors go bad.


and the diagnostics would pick that up too, what's the point here?
Yes. Yes they do. I spent a fair bit of time in a previous job learning how to distinguish between bad sensors, dead sensors, unplugged sensors and a sensor that really is telling you that something bad is happening.
Title: Re: Maintenance of weapons
Post by: SCC on 09 July 2019, 04:36:44
I think one thing people constantly over look is that BT is a world of mature, stagnate even, technology. I'm pretty sure that most people here are aware that the Pentagon doesn't exactly have the most aggressive IT upgrade. Well one of the factors that contributes to that is the restless advance of tech, but in BT things seem to have stopped some time ago, so maintaining gear is easy.
Title: Re: Maintenance of weapons
Post by: RifleMech on 09 July 2019, 08:22:46
we aren't trying to untie the gordian knot of how battletech ammo works, we're talking about maintenance. and it's not like we have a set bore for a given AC size, anyways. best to work with an average there i'd think....

Probably but sensors go bad.


and the diagnostics would pick that up too, what's the point here?

And diagnostics never go wrong? ???  A sensor could say things are good even when they're bad couldn't it?


A volley of AC/5 is somewhere in the neighborhood of 50kg. Complete rounds for 5-inch class guns are 15-25kg. They're not loading upwards of 30kg of propellant behind the shell, there would be no point. You can't propel a projectile faster than the combustion speed of the propellant, no matter how much of it you use, and physics restrains most chemical propellants to 2000-3000 m/s--hence why hydrogen/helium light gas guns are used for micrometeoroid simulations.

Besides, if ACs are single-shot weapons, there is nothing significant to differentiate them from the primitive rifle cannon. If the answer is propellant or projectile, that can be easily retrofitted to the older designs. A large-bore burst-fire weapon is the most convenient explanation for the ways ACs behave relative to everything else. Anything else requires lots of handwavium or mental gymnastics to justify.

If we go with 2 shots per round, based on rules in TacOps, then each round for an AC/5 weighs 25kg. However that would vary since the size Autocannons varies so widely.

There's still the ability to rapid fire with Rifle Cannons can't do. That'd be a total of 4 rounds, 100kg of AC/5 ammo, per turn fired, going by TacOps rules. A Medium Rifle Cannon has 9 rounds of ammo. So that's pretty close to the same number of times the weapons can fire. 10 AC/5 (double tapping) 9 MRC. So AC/s do seem to have better propellant than RCs. To compensate for the rapid firing they need to be heavier to deal with the the rapid cycling of ammo and the recoil. So the AC/5 is 3 tons heavier than the MRC.

That's looking at the rules though. Fluff wise ACs can be firing a single shot to 10 or more.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 09 July 2019, 09:34:09
And diagnostics never go wrong? ???  A sensor could say things are good even when they're bad couldn't it?

It's possible, but highly unlikely that a sensibly designed system will give you a false green.  That assumes you are taking readings from a good place in the inference space. 

A smart designer sets up the system so the simplest possible sensor will send a voltage to an analog-digital converter(ADC), and that converter will send a signal to the Diagnostic Interpreter, including error correction and sanity checks.  The DI looks to see if the reading is A: timestamps, checksums and other book keeping are in order, B: that the reading is within the happy band, and checks specific values known to indicate problems.  The thermocouple controllers at my old job would read 511oC if the wire to the probe was unplugged.   C: that the variation on the signal is sufficiently random.   That last is important.  I get nervous when I see voltage v time graph and dead flat line. That's telling me there may be a problem.
Title: Re: Maintenance of weapons
Post by: dgorsman on 09 July 2019, 13:41:52
That, and procedure.  There will be a number of visual inspections done during maintenance to spot trouble that wouldn't show up on electronic diagnostics.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 09 July 2019, 15:17:42
Visual inspections would be to look for . . .

Discoloration in material/paint, warping of a flat surface, buckling, smoke stains, excess fluid/grease in wells/low areas, oil/lubricant burns (burned oil will leave a yellowish brown residue), grass or other debris that sticks to a flat surface where it should have fallen, excessive carbon build up or scoring, excessive weathering for internal components (for example thermal liner that indicates solar/UV exposure b/c of break down), water in what should be sealed assemblies (my fav where headlights & turn signals- "See Private, that turn signal is running low on blinker fluid!  Go get some from Maintenance pronto, we do not want it to dry out!"), gray rubber seals (dried out, but not cracking- might be saved), cracked rubber seals, exposed wiring, flaking paint (why is it flaking?), rings in the paint around mounts/bolts, and . . . that is about it for what I remember for now.

You will also be checking for any difficulty opening hatches/access ports or unsteady brackets/mounts
Title: Re: Maintenance of weapons
Post by: RifleMech on 09 July 2019, 20:46:13
It's possible, but highly unlikely that a sensibly designed system will give you a false green.  That assumes you are taking readings from a good place in the inference space. 

A smart designer sets up the system so the simplest possible sensor will send a voltage to an analog-digital converter(ADC), and that converter will send a signal to the Diagnostic Interpreter, including error correction and sanity checks.  The DI looks to see if the reading is A: timestamps, checksums and other book keeping are in order, B: that the reading is within the happy band, and checks specific values known to indicate problems.  The thermocouple controllers at my old job would read 511oC if the wire to the probe was unplugged.   C: that the variation on the signal is sufficiently random.   That last is important.  I get nervous when I see voltage v time graph and dead flat line. That's telling me there may be a problem.

So it can fail and the more complicated it is the more ways it can break? 


Title: Re: Maintenance of weapons
Post by: grimlock1 on 10 July 2019, 09:27:44
So it can fail and the more complicated it is the more ways it can break?

Anything can fail. Yes, more elements in the system create more points of failure. And it is possible that a failure can be something unforeseeable.  But in 99.9999% of cases, the failure modes are understood and if they are understood you can build your system so that you distinguish between bad data and data that is telling about something bad.

The point is that even though the diagnostic systems add to the maintenance load, they pay for themselves in time and equipment saved.

Visual inspections would be to look for . . .

Discoloration in material/paint, warping of a flat surface, buckling, smoke stains, excess fluid/grease in wells/low areas, oil/lubricant burns (burned oil will leave a yellowish brown residue), grass or other debris that sticks to a flat surface where it should have fallen, excessive carbon build up or scoring, excessive weathering for internal components (for example thermal liner that indicates solar/UV exposure b/c of break down), water in what should be sealed assemblies (my fav where headlights & turn signals- "See Private, that turn signal is running low on blinker fluid!  Go get some from Maintenance pronto, we do not want it to dry out!"), gray rubber seals (dried out, but not cracking- might be saved), cracked rubber seals, exposed wiring, flaking paint (why is it flaking?), rings in the paint around mounts/bolts, and . . . that is about it for what I remember for now.

You will also be checking for any difficulty opening hatches/access ports or unsteady brackets/mounts
Enough buckling or warping to wreck a laser or PPC might not be visible to the eye. But solid state components that are approaching end of life will likely start showing some thermal discoloration.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 10 July 2019, 09:46:34
Sure, but I was not just talking about the immediate weapon- I was talking about general inspection.  The PPC or large laser that is putting off more heat may have some buckling in the cooling jacket caused by shock damage (hello shaped charge) and while the sensors may tell you the jacket has a problem, part of the first step is a visual inspection.  Buckled cooling jacket would likely mean crushed/crimped coolant flow so you do not get the spec flow rate through the tubing to move the heat to the heat sinks (as discussed, really radiators) and you can determine what tools you might need if you see damp surface around the buckled area or on any surfaces under the buckled area (like hull or internal structure) . . . which would also mean you are leaking some coolant.  What I have seen is b/c of the viscous nature of the fluid, it will be 'dirtier' than the surrounding painted/sealed metal or composite surfaces since debris will stick to it.

Again, shock damage could cause warping of the aiming gimbals & rods for any type weapon (hello, +1 TH penalty for accuracy) which you might be able to see . . . even if you get a sensor error, you will still use the Mk I Eyeball as your first inspection tool.  If you cannot visually spot any flaws, then you take out your precision tools to inspect components.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 10 July 2019, 10:45:00
Sure, but I was not just talking about the immediate weapon- I was talking about general inspection.  The PPC or large laser that is putting off more heat may have some buckling in the cooling jacket caused by shock damage (hello shaped charge) and while the sensors may tell you the jacket has a problem, part of the first step is a visual inspection.  Buckled cooling jacket would likely mean crushed/crimped coolant flow so you do not get the spec flow rate through the tubing to move the heat to the heat sinks (as discussed, really radiators) and you can determine what tools you might need if you see damp surface around the buckled area or on any surfaces under the buckled area (like hull or internal structure) . . . which would also mean you are leaking some coolant.  What I have seen is b/c of the viscous nature of the fluid, it will be 'dirtier' than the surrounding painted/sealed metal or composite surfaces since debris will stick to it.

Again, shock damage could cause warping of the aiming gimbals & rods for any type weapon (hello, +1 TH penalty for accuracy) which you might be able to see . . . even if you get a sensor error, you will still use the Mk I Eyeball as your first inspection tool.  If you cannot visually spot any flaws, then you take out your precision tools to inspect components.
Objection withdrawn.
Title: Re: Maintenance of weapons
Post by: RifleMech on 13 July 2019, 01:14:54
Anything can fail. Yes, more elements in the system create more points of failure. And it is possible that a failure can be something unforeseeable.  But in 99.9999% of cases, the failure modes are understood and if they are understood you can build your system so that you distinguish between bad data and data that is telling about something bad.

The point is that even though the diagnostic systems add to the maintenance load, they pay for themselves in time and equipment saved.

I can't help think of the later Star Trek series, The Next Generation and later where whenever something when wrong they'd yell and tap out commands on a view screen to fix the problem. I always wondered what if it was the computer screen that was wrong? Or just dirty?
https://youtu.be/-KDviXJCfHg

Who or what does the diagnostics on the diagnostics systems?
Title: Re: Maintenance of weapons
Post by: SCC on 13 July 2019, 03:26:38
Given that 'Mechs can sit in storage for at least 100 years, often in seemingly less then ideal conditions, and then be brought to battle readiness by people who have never been trained on some of it's systems (LosTech), and that none of this is a major task, I some how doubt that 'Mechs require all that much maintenance.
Title: Re: Maintenance of weapons
Post by: Caedis Animus on 13 July 2019, 04:15:33
Given that 'Mechs can sit in storage for at least 100 years, often in seemingly less then ideal conditions, and then be brought to battle readiness by people who have never been trained on some of it's systems (LosTech), and that none of this is a major task, I some how doubt that 'Mechs require all that much maintenance.
I've always headcanoned that as exceptions to the rule. Like, for every "Awww yeah pristine somehow-working Lostech" find, twenty other people find an old Locust... That has no reactor go-juice, has rats making a nest in the rusted-out machine guns, and armor plating so heavily corroded that the previous pilot's desiccated bones are more sturdy. Or a trash crate of empty MRE wrappers alongside a box of broken Mauser 960s that were supposed to be sent back for repairs a whopping 3 centuries ago-and have long since rusted to solid chunks of steel and such.

After all, if every Lostech discovery was a success story, why would finding working kit be important?
Title: Re: Maintenance of weapons
Post by: Apocal on 13 July 2019, 05:10:22
Who or what does the diagnostics on the diagnostics systems?

Mostly the same techs doing the same basic maintenance and system checks. Part of the maintenance schedule is doing a near-complete tear-down of every cabinet, power supply, connector, etc. and putting the diagnostic system through a series of basic checks to ensure it is functioning normally. There certainly are bad BIT tests that I've seen, but they tend to be found on older gear. The newer systems spit out exactly what is wrong, how to fix it and (if outright fixing isn't an option) a suggestion for re-routing or otherwise getting the system to play hurt.

We took calibrated elements to the Cal(ibration) Lab, where they managed such things using witchcraft, I assume. But elements like binary pressure sensors were extremely rugged and rarely merited much more than an annual once-over and poke-around; even then, most of their issues came about not because of their actual failure but a tired/undertrained tech re-installing them incorrectly.
Title: Re: Maintenance of weapons
Post by: RifleMech on 13 July 2019, 20:44:22
So you'd still have to take things apart and put them back together?  Hoping of course that the techs dont screw up.
Title: Re: Maintenance of weapons
Post by: Apocal on 13 July 2019, 23:16:42
So you'd still have to take things apart and put them back together?  Hoping of course that the techs dont screw up.

No, they were sealed units. The poking around was pulling them out and making sure the housing or connections were free of damage, corrosion or debris. But it was more out of a sense of "well it has to get checked at some point!" rather than any actual need.
Title: Re: Maintenance of weapons
Post by: RifleMech on 14 July 2019, 22:15:36
Oh. So how do you tell if what's inside is broken or not?  Shake it and if it rattles its broken?
Title: Re: Maintenance of weapons
Post by: Apocal on 15 July 2019, 05:03:26
Oh. So how do you tell if what's inside is broken or not?  Shake it and if it rattles its broken?

Isolate it, use known good inputs and check the output. If anything is off, you know it is something in that unit specifically. In the case of system built with true graceful degradation in mind, that might be the only way to figure out a problem with most parts of it.

The stuff described as rugged in real life has a lot of that going, inherent redundancy that keeps the operator from seeing a serious problem in the course of normal operation. I imagine Battlemechs are built with graceful degradation in mind, the myomer especially; if part of a bundle get twisted and burned out, the rest can take up the slack with only a marginal decrease in performance, but every month the mech techs have to go crawling and poking around to make sure all the bundles are within spec then replace the bits and pieces that don't pass muster. Stuff like big DC motors can be really, reliable and durable, but any serious malfunction anywhere brings them to a dramatic halt.



Title: Re: Maintenance of weapons
Post by: SCC on 15 July 2019, 05:21:25
Isolate it, use known good inputs and check the output. If anything is off, you know it is something in that unit specifically. In the case of system built with true graceful degradation in mind, that might be the only way to figure out a problem with most parts of it.
I think this can be taken as a given in BT
Title: Re: Maintenance of weapons
Post by: Colt Ward on 15 July 2019, 09:20:46
One thing to keep in mind is that military machines build in more redundancy than you are going to see on a civilian machine.  This helps it keep performing despite damage or simple break downs that can make it not-mission capable.  So performance might be degraded but you are still mission capable is the goal of a lot of military engineering.

For example, my unit in '03 was a National Guard unit that was activated to go play in the sand.  Summer of '02 one of the launchers had suffered some engine damage that put it on the side of the road during a route march back to the motorpool after EndEx.  It was fixed up and was mission capable but IIRC it was still wonky, FDC always has a semi-official list of ranking for their launchers/guns and that launcher was at the bottom after though I do not recall the exact reason.

We got activated and every vehicle in the battery was marked with chalk . . . and most were marked non-serviceable meaning they were not up to the 'book' minimum standard for operations.  But we were using those same vehicles for training all the previous year with no great change in their status but that launcher that broke down.  But we were activated and after that survey of the battery's vehicles delivery trucks started offloading pallets of boxed parts to the unit's motorpool garage which filled up two of the three bays even with troops moving boxes into the parts storage area.  First launcher into the repair bay was the one that broken down that previous summer- it also had the most chalk notations on the cab than any other vehicle.

So the vehicles could still operate and perform the mission but because of the unit's budget/priority for parts had let the vehicles degrade b/c they were limited to what repairs they were able to perform on top of regular maintenance.  While we had the bodies, think of it sort of as some of the advanced rules where a unit does not have the tech support to perform all regular maintenance on time and the rules that degrade the equipment's performance- this is especially poignant when you consider IMO that every mech, armor, BA or aero based unit SHOULD have a very very complete machine shop so they can modify or even hand build replacement assemblies.
Title: Re: Maintenance of weapons
Post by: Kovax on 15 July 2019, 11:47:32
If modern equipment is any indication, those sealed units that occasionally get replaced have circuitry and other components that require very specialized equipment and training to repair, if that's even possible.  Modern electronics frequently utilize "ball-grid array" designs, where all of the electrical connections are underneath the component, and once it's heated and sinks into place onto the pads covered in molten solder, getting it back off again is extremely difficult.  You can't get underneath it again to unsolder it.  I'm assuming that the BT universe has a lot of similar technological developments in different fields, both electronic and mechanical, where once it's built, if it doesn't work, you scrap it, or send it somewhere that has the exotic equipment to deal with the unique problems of the item in question.

The modules are also most likely designed with redundancy and internal compensation for problems.  I worked on boards that went into naval targeting systems back in the 1970s, and those had built-in bypasses and fail-safe mechanisms, so they'd at least "sort-of work" even if most of the unit failed.  Those capabilities have improved dramatically in the decades since.  I'd expect 31st Century military equipment to be at least "partly functional" even with holes punched through it.  At the low point in the late Succession Wars, most equipment was only functioning on the most basic levels, with functions bypassed, equipment suffering from multiple failures but still "usable".  Practically everything was in need of factory service to bring it back to fully operational status, but there weren't enough facilities to provide that level of service, so you swapped that module that no longer functioned for one that had "issues" but could still get you through a few more battles.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 15 July 2019, 13:14:37
Kovax also got into 'level' of maintenance . . . so current US paradigm is . . .

Operator/Crew level
Support level- can be two separate or a single levels
Depot level
'Factory' level

For an example, lets use the Po Heavy Tank of the 3030s in a combat setting.

Operator(driver) and Crew Level-  Check ammo levels, check fuel level, check fuel basket during re-fueling, check batteries, check POL levels, inspect hull for rust/burn markings, check track tension, function test MGs, not sure for ACs since its a larger caliber, check turret traverse & elevation, driving checks, lights, radios, all other onboard electronics.  Its a pretty big manual with during/daily, weekly, monthly, semi-annual and annual checklists.  This still happens, as possible, when you are in the field or in combat.

Support level-  Repair loading mechanisms, repair wheels/bogeys/suspension, repair plug & play electronics if possible, track repairs, getting a track 'unstuck'

Depot level-  Lots of refurbishment (IE, refurb the turret), replace the AC barrel, replace engine/drive train (pak), other long term or in depth repair jobs- like taking 'salvage' level purchases and rebuilding them for service.

Factory level-  Note, its not sending the vehicles back to the factory but setting up a site- even if temporary- with factory level equipment.  M577s are refit into different models, but its not like they send them back to the original factory (if it still exists) it came out of in the 50s.  So variant conversions but done in as much of a 'mass produced' model as possible.  For our example, taking in battalions if not regiments of Po Heavy Tanks to convert them into (LBX) or the Cappies making the Zhukovs into Zhukov (Liao).
Title: Re: Maintenance of weapons
Post by: Kovax on 18 July 2019, 11:06:15
For current or recent models of modern equipment, it's not unusual for individual modules or sub-assemblies to be shipped back to the factory for more complicated repairs (I've worked on a lot of stuff that was up to around 10-15 years old, long past its warranty), although having interplanetary transportation added to the equation would probably change things a bit.  In the BT universe, I would suspect that there are a handful of "factory authorized service centers" in each of the Houses where factory-level repairs can be done on most 'Mechs currently in use.

When a particular model gets too old or limited in numbers that it's no longer considered a prime asset, and is relegated to militia service or gifted to distinguished veterans, it's likely that some (or all) of the service centers no longer work on it, have the specialized tools, or stock parts, so getting advanced repairs for some of the rarer units may be next to impossible.  That doesn't mean it can't be repaired at all, but may not be able to be brought back up to its full capabilities.  It only goes as far as "depot level", if there are parts still available for that, and whatever they can't do simply doesn't get done.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 18 July 2019, 11:23:10
Yeah, depot level IMO would go along with regional command . . . so in my headcanon there is a depot level maintenance facility on New Syrtis in the FedSuns/Com for the Capellan March.  Its PROBABLY the most extensive depot in the Cap March . . . though perhaps Kathil or Talon/Wernke might rival it since they are factory worlds . . . thus parts, expertise, and equipment would be easily accessible.

Then it gets down to how regional does it go and what tiers?  For instance, a rarer machine might have to be shipped back to New Syrtis or Kathil- like say a Invasion era FWL trade machine in the 3060s while a Centurion D series only goes as far as Valexa since its the PDZ HQ because its a more common design.
Title: Re: Maintenance of weapons
Post by: dgorsman on 18 July 2019, 12:09:34
Wouldn't surprise me if some of the service centers were set up in commercial DropShips so they can be moved to better locations.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 18 July 2019, 12:25:17
Too problematic . . .

How are your engineering & tech specialist families moving with them?  Are they all loaded on the same DS?  Then how do you transport the specialized tools?  The bays in the dropship will not have the room needed for the work, so a facility will need to be found/built . . . and more.

The depot I went to once was a large indoors as a football field area, built next to the railhead, had a lot of cranes & hoists in the overhead area with catwalks, ramps & pits, birdbath, a secured warehouse or two behind, and their own POL station.
Title: Re: Maintenance of weapons
Post by: dgorsman on 18 July 2019, 16:19:27
It's not going to be moving that much, maybe once or twice a year.  They would service some of the out of the way locations which wouldn't have such fixed facilities due to dispersed forces.  They wouldn't be entirely self-contained either, just moving around the more hard to get bits.
Title: Re: Maintenance of weapons
Post by: Colt Ward on 18 July 2019, 16:57:43
Depot level maintenance however is not a regular or even standard maintenance.  The battalion or regimental support unit (CO/BN respectively) will be tasked with performing most work above operator/unit level which is why I gave the examples I did at the time.  The only reason my vehicle went to the depot was b/c they had the room and experience doing it . . . and the spare hands, we got the word go and the mechanics were working LONG hours to fix up vehicles now that the parts tap had been turned on.  Otherwise, even what we had done could have been done by our unit's support.  When they took the vehicles off originally to convert them from M577s to M1068s, they were loaded on rails and sent elsewhere.  Which is at least a depot level rebuild, if not going to the factory.
Title: Re: Maintenance of weapons
Post by: grimlock1 on 19 July 2019, 11:58:15
Can we put this in terms of formation size?
Title: Re: Maintenance of weapons
Post by: Colt Ward on 19 July 2019, 12:38:38
Sure . . . for my experience but I may not have made it clear . . .

Operator/Crew level handles the daily stuff and is carried out by the driver/crew of a armored vehicle.  For example, as the driver I was the one responsible and signing off on stuff but I was usually overseeing the FNG as he learned how to do it.  According to US Army TO&E the driver is supposed to be the newest guy as the part of starting to learn the job, in practice . . . well, driving allows you to see and know what is going on rather than rattling around in the dark of the vehicle so people with rank drove but lowbies did most of the grunt work.  If it was too big a job, or needed to be done ASAP the crew assigned to the vehicle jumped in when told (hey, they just told us we need to PMCS that humvee over there before anyone can go to lunch- its not going to be 1 guy doing it, the whole crew will get on it).

For BT mech purposes, this will be the mechwarrior and his personal tech (at least before tech team rules) who is the one personally responsible for the machine and signs off on everything.  The mech captain or crew chief (pick your term) may grab astechs out of the general labor pool if needed.

Support level depends a bit on doctrine . . . when I got in the battery/company had a squad of mechanics who were experienced with all the vehicles, controlled the parts & POL, had the more expansive tool chest, and drove the wrecker/recovery vehicles.  Each vehicle was issued a 'pioneer kit' and a specific tool box, but if you needed something specialized they were the ones who controlled it.  They also checked your paperwork and either verified by complete inspection that you did what you signed off on (no shammin'), spot checked, or took the papers b/c they knew you knew your excrement.  They fell under the commander's authority but they worked a lot with the next echelon's support element.

Which was a battalion level support element, who had more general mechanics along with a few specialists.  If we had a electronics failure, BN had a specialist who was responsible for software (sort of) and absolutely ensuring hardware was set up right.  The one time I dealt with this person, she had soldering equipment and all the other stuff you would expect from some electronics workshop in the 80s or 70s.  BN had more wreckers, and at one point was expected to set up a field garage . . . not sure if it was a tent or inflatable structure.  It was great for showing a movie on the side of the structure during a down period we were in the field.  They were under the command of a Warrant Officer.

During the Brigade Combat Team re-organization some support elements were consolidated at the battalion level due to a doctrinal change.  Before the BCT shuffle, and after, Brigade also had a level of support but I never heard of a vehicle turned over to them for care or requiring one of their techs to come down to battery or battalion level, so they may have just been to take care of the BDE HQ assets.  IMO, you could look at it as in 3025 when the basic garrison deployment to a planet might be a company, it would make sense for the company to have a slice of the battaltion's tech support while the BN HQ & assigned mech company would have the BN level tech support as part of HQ.  When we get to 3050s with battalion garrisons being the norm I think you will find them more consolidated unless the companies have to be spread out with little way of connecting.

Depot level support is going to be regional as I mentioned, so things like PDZs, theaters, or whatever unit of measure.  I doubt depot level would be assigned to a single regiment unless it was the regional primary defense force- like a national mech regiment being able to take charge of planetary militias, so it would make sense to co-locate it with the regimental HQ position.  To expand on my earlier example, lets look again at the Capellan March . . . so by strategic doctrinal organization the book might say that each of the seven PDZs has a support depot set up, or if they do not want that many as targets the FS/FC might have two in the Cap March, one for the Kathil AO and one for the Taygeta AO.  Depot level support is likely under regional command, depending on what that region size is to begin with . . . though I guess you could say the March HQ would be in charge of the PDZ Depots rather than PDZ commanders.

'Factory' level support that will not be based out of a operational factory might be the DS mobile operation like you suggested, especially if there is a big refit program (like hey, 3051! or 2SW tech-downs) operation underway.  Place that 'Factory' level team down in a central protected location and instead of it taking months for that company of Vedettes to travel somewhere, be refit with UAC/5s & other upgrdes, and then months to travel back . . . instead the 'Factory' comes to a region where everyone ships their Vedettes for a month of travel.  IMO this sort of level of support would be under the Army command structure, so for our Cap March example of a Kathil (b/c producing factory) probably gets it assignments from the Quartermaster Corp HQ on New Avalon.

Does that help?
Title: Re: Maintenance of weapons
Post by: idea weenie on 20 July 2019, 23:23:32
How are your engineering & tech specialist families moving with them?  Are they all loaded on the same DS?  Then how do you transport the specialized tools?  The bays in the dropship will not have the room needed for the work, so a facility will need to be found/built . . . and more.

The depot I went to once was a large indoors as a football field area, built next to the railhead, had a lot of cranes & hoists in the overhead area with catwalks, ramps & pits, birdbath, a secured warehouse or two behind, and their own POL station.

Would multiple Dropships transporting a single depot maintenance unit work, if they were for only a single design?  I.e. multiple Mammoths transporting the tools and dies needed for modifying only the Vedette series of tanks?

So the Dropship(s) would go to a planet that could support it, offload the necessary equipment into a prepared building/location, and other units have used commercial Dropships to send their Vedettes to that planet for modifications.  Once all the Vedettes in the region are modified (~1 year later?), the Dropships are packed back up and sent on to the next region.  (Advantage is shorter shipping distances while the depot unit is in the area; disadvantage is the hogging of transportation assets when it is time to move)

Or would it be better for the Vedette upgrade facility to be left in one area, and the various combat groups to ship their tanks to that location for modifications?  (Advantage - no hogging of transportation assets, local families establish a better relationship; disadvantage is more shipping distance between the frontier units and the depot)
Title: Re: Maintenance of weapons
Post by: Daryk on 21 July 2019, 06:00:11
Interesting idea, but definitely one for the accountants!  :thumbsup:
Title: Re: Maintenance of weapons
Post by: Colt Ward on 21 July 2019, 11:05:17
Or would it be better for the Vedette upgrade facility to be left in one area, and the various combat groups to ship their tanks to that location for modifications?  (Advantage - no hogging of transportation assets, local families establish a better relationship; disadvantage is more shipping distance between the frontier units and the depot)

Which is why I mentioned that a mobile rebuild 'Factory' would perhaps be better, since you also have to factor in that while all those Vedettes are missing from their unit you have guys standing around in the motorpool with hands in their pockets.  From my experience its not really the work that might take that long, but you would be looking at the week up, weeks charging, and week down . . . so at least 3 weeks shipping not including the week or two rebuilding.  So if you were in the next system over you are looking at 4-5 weeks vulnerability.

More likely what happens is . . .

"Okay, the DLC does not need these old Succession War era Vedettes, they got the new fancy ones with the Ultra cannon straight from the factory.  We are going to send the battalion or so that were assigned to them to Depot #48.  Depot $48 will rebuild them, pull their old standard cannons and replace them with the reconditioned experimental/used Ultras to bring them up to spec.  We will then send those Vedettes off to the Sarna March Militias to replace a company of Scorpions in as many of the SMM units as we can.  The old Class 5 autocannons we pull out of the rebuilds?  Have the depot modify them to mount on a field gun carriage, we will send them with the reconditioned Vedettes to beef up the SMM infantry battalions."

Logistical managing is a skill, and part of how they test you is handing you a lot of sharp objects and things that go boom to see if you can keep them in the air.
Title: Re: Maintenance of weapons
Post by: Col Toda on 26 August 2019, 11:12:45
Maintainace is taken to a certain extent with spare parts . The longer the engagement lasts the more damage sustained the more parts expended .  Short term throw weight of ammo using guns with veteran pilots c3 and or TAG : precision rounds ect . Shortens the conflict to a brutal 10-12 Turns after which You have ethier won or lost vs energy boat oppostion . Use of the above equipment tends to bear energy w targeting computers hands down .
Title: Re: Maintenance of weapons
Post by: Kovax on 28 August 2019, 11:11:57
I once got shipped off to a factory building adjacent to a military airfield, where instruments were pulled out of aircraft to be modified, exchanged for modified instruments which were quickly put back in place, and the planes were gone in a matter of an hour or two.  Meanwhile, we sweated for 16 hours a day to do the modifications as they came in, along with updating a backlog of units which were awaiting installation.  The really sad part is, we (a couple of lowly techs with a couple of decades experience at troubleshooting and repair) knew that the "upgrade" wouldn't solve the problem, but nobody higher up would listen to us....until the modified units started failing, and heads rolled higher up in the company (after we pulled out the reams of data we had compiled to protect out own jobs, showing that we had done our part exactly as directed, despite our complaints up the ladder being ignored).  I was painfully reminded of several of the TRO 3050 "upgrades".

In that case, a "factory" repair was performed at a "factory level" site by a "factory" team, but that wasn't the factory where the units were produced or normally serviced, it just had to have the right tools, parts, and personnel at hand to do the work.  In other words, a "factory" repair can be at a fixed location, or mobile, depending on need.  If someone had brought in some other instrument in need of repair, we wouldn't have had the parts to work on it, but did have everything needed for the specific modification we were sent to do.  Other items requiring that level of service would have been sent back to the actual factory, where a wider range of parts and equipment were available, as well as techs more familiar with those other instruments.

An experienced tech with an old soldering iron and a few other electronics-related hand tools, as well as a box of "common" parts for that instrument and proper schematics for the item in question, could probably handle most of the routine repairs.  Someone with basic mechanical skills and normal tools wouldn't be able to do much to fix it, other than to tap it against the table to see if something was loose (oops, well now something IS loose), and would need to swap out the gauge for a working one.