All Warships Should Have Drop Tanks
- Thread starter Theophilus
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http://traveller.mu.org/errata/ffs.errata.htmlFFS2 errata said:
I think this is ridiculous, myself
What is so special about drop tanks that they won't work until tech-15 jump drives exist, yet battle riders are just peachy before then?
FFS2 is set at the start of the Third Imperium (year 0), so battleriders exist in the OTU's history prior to 1090.
Why does a drop tank hinder jump drives, but battleriders don't?
Or is it that battleriders, which would use the same technology as drop tanks, weren't invented until 1090 too?
for TU's that don't use reactionless thrusters, drop tanks can be very useful.
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The thing is, it also has to make sense. Military grade drives would not only have to cost more than civilian drives (it's, IMO, a mistake that they don't), they would have to cost so much more that it would eat up any profits form using drop tanks. Otherwise civilians would just buy military grade drives and use the drop tanks.
I have nothing whatsoever against drop tanks. On the contrary, I'd like to explore the effects of introducing drop tanks in a society that doesn't have them, with all the economic upheaval and associated shenanigans. I'm looking forward to the day I come up with an adventure plot that requires being set on a jump-6 drop tank liner. What I don't like is retconning drop tanks onto a setting that didn't have them originally.Hans, you really, really, don't like drop-tanks do you?!
Also, I have to admit, I don't think they're quite the panacea the original poster makes them out to be. As I've indicated, I think there are costs as well as benefits to using them. And he did ask for opinions, didn't he?
Instead of saying, "You're right, let's retcon the Tigresses into 700,000T dreadnaughts with drop tanks", I think it would be interesting to explore those costs and figure out why the Imperial Navy is still building new Tigresses (GT canon -- there's mention of a Lioness II that replaces the Lioness, lost in the 5FW).
Hans
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From a logistics standpoint military use of drop tanks only makes sense... depending upon the safety of the process. Let me ballpark a number: 10%. This is a notional upper limit that no military would accept as a jump casualty rate, though in reality we could look for less than 5%. As long as the casualty rate is low enough... wether you accept my ballparks or set your own... then the Navy would have to accept Drop Tanks for projected force as doctrine.
Here is why:
Take any two warships of any given tonnage and jump drive. The ship that dedicates less tonnage is objectively more capable, the larger the jump drive the more obvious, while the larger the ship the more forgiving.
Lets look at the most obvious: 100 ton 'frigates' with Jump 4 drives.
40 tons of additional armor, weapons and redundant systems. The ability to carry 4 light fighters or gun drones.
For every single ship of that size in the fleet.
Consider too that every offensive military force is going to be engaging canon System Defense Boats that not only don't carry jump fuel but don't even have a Jump Drive at all! (An additional 10+ tons of weapons, armor, support craft or marines... whatever).
Traditionally it takes a three to one ratio to beat defenders, disregarding all other factors (which, honestly, don't necessarily exist in space), with the mass difference caused by jump fuel considerations, that becomes closer to a 6 to 1 ratio.
Let me expand this a bit: Tactics win battles, strategy wins wars. Jump Fuel, the ability to Jump at all, is not Tactical in any sense, not with a 1 week each way timeline. It is purely, powerfully, strategic however, the faster fleet can outmanuever slower fleets, choosing where to fight, though in both cases intelligence is problematic.
I would think, as a general rule, that most warships do have some 'on board' jump fuel of course, say 20% of volume (Jump2, natch) which allows them to operate independently of the support fleet at a reduced capacity, the trade off between tactical mass and strategic mass, though that could, in fact, be limited to specific hulls.
Regarding Drop Pods themselves: I would think that the actual pods would be more akin to fuel blivits, at least the ones used by the military. Fleet tenders would be on station to retrieve and refill the blivits/tanks for the next wave of deployment, and there would be 'fueling stations' set up in advance of a deployment... probably the best indicator of where a fleet is going is where their advance fleets set up shop. This is faster but riskier and more dangerous than the slower process of bringing the fuel tenders and scooping and purifying and filling the tanks as the fleet moves.
This actually suggests that a strategically designed fleet would have at least three classes of warships: SDB's, Fleet ships (what I've been discussing), and patrol ships (independent ships, weakest in their tonnage but most strategically flexible... you know, the conventional ships in the Traveller setting as written).
Here is why:
Take any two warships of any given tonnage and jump drive. The ship that dedicates less tonnage is objectively more capable, the larger the jump drive the more obvious, while the larger the ship the more forgiving.
Lets look at the most obvious: 100 ton 'frigates' with Jump 4 drives.
40 tons of additional armor, weapons and redundant systems. The ability to carry 4 light fighters or gun drones.
For every single ship of that size in the fleet.
Consider too that every offensive military force is going to be engaging canon System Defense Boats that not only don't carry jump fuel but don't even have a Jump Drive at all! (An additional 10+ tons of weapons, armor, support craft or marines... whatever).
Traditionally it takes a three to one ratio to beat defenders, disregarding all other factors (which, honestly, don't necessarily exist in space), with the mass difference caused by jump fuel considerations, that becomes closer to a 6 to 1 ratio.
Let me expand this a bit: Tactics win battles, strategy wins wars. Jump Fuel, the ability to Jump at all, is not Tactical in any sense, not with a 1 week each way timeline. It is purely, powerfully, strategic however, the faster fleet can outmanuever slower fleets, choosing where to fight, though in both cases intelligence is problematic.
I would think, as a general rule, that most warships do have some 'on board' jump fuel of course, say 20% of volume (Jump2, natch) which allows them to operate independently of the support fleet at a reduced capacity, the trade off between tactical mass and strategic mass, though that could, in fact, be limited to specific hulls.
Regarding Drop Pods themselves: I would think that the actual pods would be more akin to fuel blivits, at least the ones used by the military. Fleet tenders would be on station to retrieve and refill the blivits/tanks for the next wave of deployment, and there would be 'fueling stations' set up in advance of a deployment... probably the best indicator of where a fleet is going is where their advance fleets set up shop. This is faster but riskier and more dangerous than the slower process of bringing the fuel tenders and scooping and purifying and filling the tanks as the fleet moves.
This actually suggests that a strategically designed fleet would have at least three classes of warships: SDB's, Fleet ships (what I've been discussing), and patrol ships (independent ships, weakest in their tonnage but most strategically flexible... you know, the conventional ships in the Traveller setting as written).
But the salient comparison is between ships of equal cost. The ship that dedicates 40% of its tonnage to fuel tanks costs less than the one that dedicates those volumes to weapons and armor. That's why riders are tougher than their jump-capable tonnage-equivalent ships.
Things gets even dicier when you consider that the principal use of a combat vessel of a given tonnage is as a platform for one spinal mount. By making your individual ships more expensive, you get fewer spinal mounts for the same amount of money. Depending on the size of the target, spinal mounts may be able to mission-kill one opponent per shot. Under such circumstances, you want as many spinal mounts as you can scrape up.
Hans
Hi
Maybe it would be useful to put together two fleets, one with drop tanks and one without, to let everyone see how they compare in costs, manpower requirements, and the like. Then everyone could better discuss there relative advatages and disadvantages in relation to attack missions, defenseive missions, deep strik raids, and other such missions that a typical fleet might be called upon to perform, and especially how the logitics associated with the use of drop tanks might impact these missions.
Regards
PF
Maybe it would be useful to put together two fleets, one with drop tanks and one without, to let everyone see how they compare in costs, manpower requirements, and the like. Then everyone could better discuss there relative advatages and disadvantages in relation to attack missions, defenseive missions, deep strik raids, and other such missions that a typical fleet might be called upon to perform, and especially how the logitics associated with the use of drop tanks might impact these missions.
Regards
PF
Missed this the first time around. You're using the full 40% internal fuel tankage for other purposes. That means that a drop frigate without its drop tanks are incapable of jumping at all. Unless I'm mistaken, that's not what the OP wanted. He wanted the frigate to be able to make a 4-parsec jump into a hostile system with enough fuel left over to make a full 4-parsec jump back out again. That means either carrying around 40% extra external fuel tankage, making the frigate a 140T ship for purposes of routine jumping or being accompanied by freighters carrying the drop tanks until they are needed.
Hans
The Oz
SOC-14 1K
It does work for civilian traffic, which is why you find the "highports" IMTU just outside of the 100D limit. But only at high-tech, high-pop worlds that would have lots of jump traffic. And since I use jump masking IMTU, very busy ports (Class A, Pop-9+, TL-14+) even have more than one "highport" so that ships can always jump straight to their destinations.
But then MTU is quite a bit different (economics, politics) from the OTU, so we're comparing apples and oranges.
I do agree with Hans that retconning drop tanks (or any similar tech) into the OTU is a rough job and probably not worth the trouble. If I played in the OTU I'd just cut drop tanks out entirely.
Theophilus
SOC-13
I'm glad to see we've gotten so much discussion on the subject.
I hadn't considered using drop tanks for freighters, although the extra cargo capacity, and a dedicated route with tanks on each end would make great sense.
And my original statement was that warships should have the capability, not necessarilly use, drop tanks. Another consideration is combat damage. A ship fitted out to use drop tanks could still be refuelled and jump even with all there internal fuel tanks shattered. Thus saving a valuable ship for later use.
Now lets see some designs:
1. A 100 kton jump-4 battleship with four 10kton drop tanks(dropped for jump, not carried from system to system), compared to a standard bb of the same tonnage.
2. A 30 kton jump-3 cruiser with one 10kton drop tank allowing Jump three (3000 tons per jump/10,000 ton tank)
3. A 10kton drop tank for both.
I hadn't considered using drop tanks for freighters, although the extra cargo capacity, and a dedicated route with tanks on each end would make great sense.
And my original statement was that warships should have the capability, not necessarilly use, drop tanks. Another consideration is combat damage. A ship fitted out to use drop tanks could still be refuelled and jump even with all there internal fuel tanks shattered. Thus saving a valuable ship for later use.
Now lets see some designs:
1. A 100 kton jump-4 battleship with four 10kton drop tanks(dropped for jump, not carried from system to system), compared to a standard bb of the same tonnage.
2. A 30 kton jump-3 cruiser with one 10kton drop tank allowing Jump three (3000 tons per jump/10,000 ton tank)
3. A 10kton drop tank for both.
The Oz
SOC-14 1K
If the ships are using the drop tanks just for additional fuel (that is, they still have their full jump fuel tonnage internally as well) the designs of the two ships (drop tanks vs. non-drop tanks) will be essentially identical. The difference between the two ships is not in design, but in operational/tactical use, and in economics. Ships that use drop tanks for outward jumps (to attack an enemy system) will always have the freedom of retreat without refuelling, even at maximum jump range. Ships without drop tanks cannot retreat without refuelling, which implies needing to win control of the star system long enough to make use of the fuel sources within.
The economic difference comes mostly from the need to provide a supply of drop tanks and a means of transporting and refilling the drop tanks when and where needed.
Hi
In addition to the need for the transports and other stuff that "The Oz" mentioned above, I guess that there is also the issue of what the ships will do if an enemy jumps into the system where they are.
Specifically, if an enemy jumps into the same system where your drop tank equipped vessels are currently located, do the ships with drop tanks keep the tanks connected until needed, effectively impacting their acceleration ability and potentially other factors (since a notionally 100,000 dton ship with drop tanks would effectively now be a 140,000 dton ship)? Or do the ships with drop tanks immediately drop them once an enemy is sighted so that tactically a 100,000 dton ship with 40,000 dtons of drop tanks will now be operating only as a 100,000 dton ship (for acceleration and other purposes), but effectively now loosing any benefits that the drop tanks would have given.
I'd suspect that the decision would depend on the tactics and strategical situation in each case, but there are alot of things to be considered and this may be a situation where drop tanks are actually a detriment because they (and the transports/tenders that they may require) are an added expense and if immediately dropped they wouldn't seem to provide any operational benefit) but if kept attached, they may actually be a tactical detriment, since the ships will have lower acceleration capabilities (and potentially other detriments - for example depending on which version of the rules I think that there a potential for reduction in the number of weapons that can be brought to bare - if I am recalling correctly).
Anyway, just some additional thoughts to consider.
Regards
PF
In addition to the need for the transports and other stuff that "The Oz" mentioned above, I guess that there is also the issue of what the ships will do if an enemy jumps into the system where they are.
Specifically, if an enemy jumps into the same system where your drop tank equipped vessels are currently located, do the ships with drop tanks keep the tanks connected until needed, effectively impacting their acceleration ability and potentially other factors (since a notionally 100,000 dton ship with drop tanks would effectively now be a 140,000 dton ship)? Or do the ships with drop tanks immediately drop them once an enemy is sighted so that tactically a 100,000 dton ship with 40,000 dtons of drop tanks will now be operating only as a 100,000 dton ship (for acceleration and other purposes), but effectively now loosing any benefits that the drop tanks would have given.
I'd suspect that the decision would depend on the tactics and strategical situation in each case, but there are alot of things to be considered and this may be a situation where drop tanks are actually a detriment because they (and the transports/tenders that they may require) are an added expense and if immediately dropped they wouldn't seem to provide any operational benefit) but if kept attached, they may actually be a tactical detriment, since the ships will have lower acceleration capabilities (and potentially other detriments - for example depending on which version of the rules I think that there a potential for reduction in the number of weapons that can be brought to bare - if I am recalling correctly).
Anyway, just some additional thoughts to consider.
Regards
PF
Theophilus
SOC-13
Exactly my point, Ship wise there is no differnce in the ship, the cost is in drop tanks and tenders which don't necessarily enter combat. As to PFVA63's comment, That's close to the tender/battlerider arguement, do I drop riders or retreat.
I think the strategic advantage would make drop tanks for offensive operations common. Since my base is ten parsecs from your's and everyone knows you can't to jump 10, well, uh, umm, howed you get here? Drop Tanks.
Hey, you just jumped insystem, my scout heads out to my base, we've got time, You've got to skim and refine fuel. Hey, howed you get here right behind my scout? Drop Tanks.
far-trader
SOC-14 10K
Or deep space fuel caches and I topped up the tanks less than a parsec out so I still have reasonably recent intel (1 week old) by long range observation and J3 left in my fully mobile and fully armoured J4 fleet
Maybe even before your scout* since we can jump pdq behind you, thanks to our deep space fuel caches above and I still have J2 left in my fully mobile and fully armoured J4 chasers
* especially if I send more than one ship after it
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So your ships just jump around with the drop tanks attached but don't use them for routine operations. You've just reduced their effectlive jump range for routine operations by two (J4 to J2, J5 to J3). The added cost isn't so bad -- less that 0.1% -- so long as you don't use the things. But every time you do use them, it'll cost you another set of tanks.
As I said, there's no doubt that drop tanks give a strategic advantage. The question is, do they give one that's worth the cost? That would partly depend on the astrography of your theater.
But then you'd arrive with empty tanks, having used your drop tanks for the first jump and your internal tankage for the second.
Hans
That is an excellent point but it also suggests some errors in the ship designs as presented beyond drop tanking. If (and I must stress the IF of if, since I have not got any experience in the High Guard combat rules to suggest rules based flaws), we accept that spinal mounts are the be all end all of naval combat what we should be seeing is a whole raft of gun ships, basically flying spinal mounts with manuever engines and not much else. Armor becomes a waste of time and money since Spinal Mounts cut right through it.
The Ideal warship then is suggested to be a big flying 'hangar bay' for these flying spinal mounts (Riders?), which are unleased en masse as soon as they hit a target system.
Real life examples of warfare (ground and naval both) would suggest that a combined arms approach would work well here, with a smaller number of light ships whose primary purpose is to defend the mass of flying guns from 'lesser threats' that were otherwise mooted by naval defense prior to the dominance of spinal mounts (missiles and fighter craft namely).
Such overspecialization is a deathknell for any military force eventually, of course. I rather suspect the entire line of thought about how every ship is nothing more than a mount for another spinal mount is just silly fluff.
On the other hand, we can see that building bigger ships reaches a point of diminishing returns tactically unless its primary purpose is as a carrier for smaller, nastier ships... though I am reminded of a parable involving eggs and baskets...
By focusing only on the change in drop tanks I can assume that the rest of conventional military thinking, a la Traveller, can remain more or less intact. Ships with more usable mass per jumpable ton are both better specialists and better generalists, yes?
Of course, I lack the vast depth of traveller lore of most posters here, so I am happy to caveat all my wild ideas with whatever dismissives y'all want to use to tell me I'm flat wrong.
With respect to game balance drop tanks aren't too much more unbalancing than fuel scoops and on-board fuel processors. IIRC the "proper" amount of time between two jump is about 16 hours to check all a ship's systems. With this time taken, the average time to complete a double jump (with fuel pods) would be roughly 352 hours. Assuming it would take 36 hours to scoop and process fuel for a second full jump the average time to complete a double jump would be 372 hours. Having drop tanks rather than refueling at a gas giant is a rough 20 hour savings. This might give a fleet a leg up on the competition assuming they jump really close to their target and don't have to wait to form up if any ships in the fleet mis-jumped.
I see drop tanks are useful but not really game changing. They would be fantastic for a deep strikes or reconnaissance missions. For deep strikes you can either make a deep attack into enemy territory hopefully bypassing a "crust" defense or can reenforce friendly sides on your own border. Recon missions are the only type I think are really viable for the jump-in/jump-out model since they're less likely to be actively pursued when they make their jump back out of the system.
If your fleet jumps into a system and find itself outgunned if they need to decide to do so immediately. If they wait to engage the opposition they'll be harried during their retreat and jump preparations either disabling their jump drive or causing potentially disastrous mis-jumps.
I see drop tanks are useful but not really game changing. They would be fantastic for a deep strikes or reconnaissance missions. For deep strikes you can either make a deep attack into enemy territory hopefully bypassing a "crust" defense or can reenforce friendly sides on your own border. Recon missions are the only type I think are really viable for the jump-in/jump-out model since they're less likely to be actively pursued when they make their jump back out of the system.
If your fleet jumps into a system and find itself outgunned if they need to decide to do so immediately. If they wait to engage the opposition they'll be harried during their retreat and jump preparations either disabling their jump drive or causing potentially disastrous mis-jumps.
Theophilus
SOC-13
Or deep space fuel caches and I topped up the tanks less than a parsec out so I still have reasonably recent intel (1 week old) by long range observation and J3 left in my fully mobile and fully armoured J4 fleet
Maybe even before your scout* since we can jump pdq behind you, thanks to our deep space fuel caches above and I still have J2 left in my fully mobile and fully armoured J4 chasers
* especially if I send more than one ship after it
Where are you placing your deepspace refueling sites? Am I correct that your saying one parsec from the target system?
Reasonable intel? If it takes me one week to jump to the refueling site, and one week to jump to the target system wouldn't that make my intel two weeks old? And If my scout's information is one week old (minimum) when I reach the refueling site wouldn't that make three weeks? Of course If the scout jumped to the refueling site at the same time I did then it might only be a week old. But timing over interstellar distances, with Murphy's delay's and whatnot?
Can you jump reasonable soon behind my scout? A stealthy scout detects the Jump flash of your entry into the system, several hours old at light speed. By the time it know's I'm here I've already left the Kuiper belt on my way to my target.
Consider this. A AHL with J5 drives and droptanks leaves the naval base at Jewel. Jump 5 to Sachebr, and then to:Cronor, Zhdienshdo, Bretrie? you decide.
A standard AHL would have to refuel at Sachebr, where there is a Zhodani Naval Base, and most fuel locations would probably be guarded against just such a strike. Actually, the AHL could just jump into hex o706 and then on to Chronor. I admit refueling at Chronor and getting back is a problem, But If my fuel tenders brought drop tanks to 0706 I could retank, Strike and return to 0706 to refuel.
Thus, the use of drop tanks, strategically. Would all ships need to be fitted with drop tanks? No, but strike and raiders would benefit from drop tanks. And having the fittings available to replace shattered fuel tanks so ships could escape the combat zone would seem advisable, since the actual tank fittings are negligable.
Hi
Hi,
I'm having a little trouble following this, since I think some names and locations change from source to source. But, if using the 5th Frontier War Map, if Sachebr is the same as Cipango, and 0706 is the same as the hex just below that system, and Zhdienshdo, is Gesentown (as the Traveller Wiki suggests), then these appear to be Jump 4 jumps. As such, there appear to be some alternate routes even without Drop tanks. (Specifically, if you go J5 from Algebaster, the 5th Frontier War Map appears to show that there is water available for fuel there. You could then refuel and J-3 to Cronor, and then J-2 out to Whenge (which is also indicated to have water for fuel) and then J-5 back to Ruby in Imperial space.
Regards
PF
Hi,
I'm having a little trouble following this, since I think some names and locations change from source to source. But, if using the 5th Frontier War Map, if Sachebr is the same as Cipango, and 0706 is the same as the hex just below that system, and Zhdienshdo, is Gesentown (as the Traveller Wiki suggests), then these appear to be Jump 4 jumps. As such, there appear to be some alternate routes even without Drop tanks. (Specifically, if you go J5 from Algebaster, the 5th Frontier War Map appears to show that there is water available for fuel there. You could then refuel and J-3 to Cronor, and then J-2 out to Whenge (which is also indicated to have water for fuel) and then J-5 back to Ruby in Imperial space.
Regards
PF
And that's the real point. Theophilius is perfectly right about drop tanks being an advantage. The alternatives are not as efficient (especially not the deep space fuel depot -- the logistics of establishing one can be tremendously complicated). But they are there. So are the drop tanks worth what they cost? They may or may not be. Do the people that holds the purse strings think that they're worth the costs? They may or may not. I just think that the original blanket statement about how ALL warships should have drop tanks is a bit too broad for my taste. Even if we ignore the point about the majority of the Imperial Navy having been built before the invention of drop tanks.
"And, you know, if we allow the Navy to have drop tanks, they'll just use them even when they're not needed, and that costs money. Better not. We've managed fine without drop tanks for a thousand years and more. These newfangled ideas are never as good in reality as they look on paper." [Count Damien Tancredi, Imperial Minister of Finance, 1090]
Hans
Hi
Hi,
I think that's what got me too. I can see areas where drop tanks can be used, but that doesn't necessarily negate that there may also be other options that may also work. Then again, even if by the rules everything seems like it should work, there is also the issue of if we were trying to be realistic, how exactly would they work.
For instance, taking the Azhanti High Lightning as an example, how do you actually fit the tanks on in such a way that they can be easily dropped but at the same time have them not impact weapon firing arcs, the location of the thrusters or other such things.
Regards
PF
Hi,
I think that's what got me too. I can see areas where drop tanks can be used, but that doesn't necessarily negate that there may also be other options that may also work. Then again, even if by the rules everything seems like it should work, there is also the issue of if we were trying to be realistic, how exactly would they work.
For instance, taking the Azhanti High Lightning as an example, how do you actually fit the tanks on in such a way that they can be easily dropped but at the same time have them not impact weapon firing arcs, the location of the thrusters or other such things.
Regards
PF
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