All Warships Should Have Drop Tanks

[Hal]

About interchangable drop tanks, I assume that they are (for Navy at least) an element so important as to be IDP (Imperial Design Product), so at least partialy standarized or modular, so they can be adapted for most Imperial Navy ships.
About using them on X-boats, my assumption here is that the lack of maneover drive precludes X-boats to make independent jumps, relling on tugs or tenders to put on the exact space point needed to make the jump, so their use will not help unless they have some way to maneover.
So said, remember I'm not partidary of indiscriminate use of drop tanks, just I see some uses for them, mostly on friendly space and for preplanned moves.

I find that hard to swallow. Using drop tanks from a hull configuration 1, size 8 hull, would not work so well on a hull configuration 3, size B hull. If people are postulating that these add on hulls are available in large lots at various star ports, it would be an interesting logistical supply problem to determine how many of these drop tanks have to be prefabricated AND deployed on the off chance that they might be used by any given ship at any given time. For instance? Lets say that you want 100 of these drop tanks ready at any given time for 10 ships that can call at a given port at any given moment. Right then and there, the cost for these drop tanks are no longer negligable. Now, lets look at this in another light. Each drop tank takes 10 weeks to manufacture. 100 drop tanks for 10 weeks apiece is not an inconsequential set up. Allocating production of say, 120 dton drop tanks for 10 weeks production time, would require roughly 12000 dtons of shipyard capacity.

At least, that is how I'd interpret the rules from Trillion Credit Squadron.

 

[Hal]

I think that was mentioned earlier in the thread, but my misgiving is the need to put enough distance between the Jump Tanker and the fuelled vessel before the jump occurs - so the tanker's 100 diameter limit doesn't threaten a misjump.

One thing to keep at the back of your mind is this:

Certain rules were not existance at the start of Classic Traveller, and in some instances - a given rule was introduced in one game system, but discontinued in later game systems (compare Traveller New Era versus MT before it, or any of the systems subsequent to it).

One thing I do get a gut feel for is that as of 1105, drop tanks were expected to become a potential part of day to day operations for ships - so much so that Jump-6 couriers were expected to exist, as well as escort ships with drop tanks, etc. But more importantly, it was part of the storyline in the early days of Classic Traveller, that the issues involving misjump mishaps were not predicated on ships being within 100 diameters of the drop tanks when they jumped, but instead, were the results of a failure to separate properly when the ship attempted to jump with the tanks still attached. WHich makes me wonder a bit. If one can jump with the drop tanks attached without problem, and one can jump without the drop tanks - supposedly without too much of a risk - might the problem occur when the ship intends to jump to a new destination, and has a pre-calculated "jump field" size (ship without drop tank) that has serious consequences when the ship jumps with more "hull" than intended?

By the by? The "tragedy" that occurred involving a failure to separate properly, occurred with an 800 dton liner.

Overall? It would seem to me, that in light of all of this, perhaps the reason the drop tanks were not part and parcel of further Traveller products is because it was decided quietly by the powers that be at GDW, that drop tanks aren't perhaps all that viable. Perhaps no one could come up with viable rules to use in conjunction with the drop tanks, or perhaps they were busy with their normal activities and didn't spend a lot of time dwelling over the finer points that we are engaging in some 30+ years later

So, first mention of Drop tanks in the Fifth Frontier War rules indicate that in the spinward marches, they were being used/developed in 1105 (news release was dated 097 - 1105. By 201-1105, there were explosions at the manufacturing plant/assembly line, and by 186-1106, news (1 month late) was getting out about the tragedy and of the 217 lives lost in the accident.

Just thinking aloud. Gut feeling? If the ships were being built prior to the introduction of drop tanks were "fine" without the drop tanks, they wouldn't take the time nor effort to change their configuration. Why? As pointed out earlier, you can't change all too much of the ship's drives, powerplant, etc - and removing fuel tanks from a ship design that was originally not designed for drop tanks, means that the ship has to be laid up in the ship yard (not generating revenue), gutted and then rebuilt to specs (costing money to do so) and then having to go through a testing period to insure that the ship was spaceworthy and would function as designed. Once released into the hands of the owner, the ship now has to deal with the following issues:

If drop tanks are popular - the ship will be in competition with other ships trying to purchase functional drop tanks. If production is not keeping apace with demand, what then?

If drop tanks are unpopular - the ship will have to scrounge for drop tank production from shipyards that are increasingly deciding that manufacturing tanks on speculation is not a good idea. That means that the ship's captain would have to purchase those tanks in lot sizes larger than for immediate use, and those drop tanks not being used, have to be shipped elsewhere in preparation for use, which in turn incurs a storage fee when not in use.

Last but not least:

You've got a whole passal of ships that were designed to last a few decades, and the ship you have now isn't intended for use with drop tanks. Do you modify the ship so that it takes advantage of the removal of current fuel tanks being removed and subsequently handled by drop tanks?

Is there any real difference between adding more internal fuel tankage so that all ship designs include enough fuel for N+1 parsecs travel where N = jump number of the drive itself - and ships equipt with drop tanks?

Here is my challenge:

Design a 3,000 dton warship without drop tanks using TL 14 technology constraints. Then build a new 3,000 dton warship designed to use drop tanks, capable of performing the same mission as the original 3,000 dton destroyer (ie try to get the same weapon capabilities, armoring, etc). Factor in the new architech's fee, then factor in the cost of the first prototype hull. Then, last but not least? Calculate the cost of 100 jumps (a 4 to 8 year use of the ship depending on whether it jumps 1 to 2 times a month). Might not some bean counter ask "Don't we have better use of money than to convert from the older hulls to the newer hulls?" Then, as if that weren't enough - what happens when those ships are mothballed or sold to colonial fleets? You're still stuck with the older methodology until those ships are retired from front line duty of not only the Imperial Navy, but also the Colonial navy.

 

[Hal]

Simply, I don't think there should be a "special" drop tank. I'd rather have documentation of the Jump process (fuel consumption, charge time, hold time, issues with near space bodies, etc.). Because thats what all this centers around, frankly, the rest is just engineering (and I would argue straightforward engineering). I don't know why the system of engineering that is Traveller ship construction can support the concept of Battle Riders, but not "Tanker Riders", or that those "Tanker Riders" can't undock conveniently before Jump.

A space based drop tank needs a detachment mechanism (explosive bolts, docking grapple, or whatever) and an acceleration mechanism to facilitate separation, ranging from a solid fuel rocket booster (like the Space Shuttle uses for the SRBs when they separate) to something as sophisticated as an M-Drive for a reusable tank.



I could swear I had seen reference to caches pre-TNE, but I am hardly a Canonista.

I think there is a difference between dropping off Battle Riders in one turn of combat (20 minutes) while perhaps in reserve, then initiating a jump the next turn, and taking another turn to conclude the jump (unless you have twice the energy required to jump). Grand total of time spent dropping off battle riders and jumping is 1 hour.

In addition? If one can make Tanker Riders - why pay the full cost for a hull when you can buy fuel tank hulls at cheaper costs? Either the drop tank hulls are flimsy and cost less than normal hulls, or they are sufficiently structurally sound, and all hulls should cost that much to make. Also?

What do you do when someone purchases a drop tank, but doesn't drop the tank, and is shot at by an enemy who is using a factor 4 missle attack? Since drop tanks aren't armored, what do you do when the ship being fired at is armored, but its drop tanks aren't?

 

[rancke]

One thing I do get a gut feel for is that as of 1105, drop tanks were expected to become a potential part of day to day operations for ships - so much so that Jump-6 couriers were expected to exist, as well as escort ships with drop tanks, etc.

Without getting into the original intentions of the writers, drop tanks was already a part of day to day operations for some ships in 1105. At least, I don't see Tukera waiting until they can buy drop tanks at Regina and then inargurating a chain of drop tank liner routes from Core to Regina in one fell swoop. When the newsbrief talk of opening service to Regina 'from the interior', I take it that Tukera is already running drop tank liners from the interior to Rhylanor, and that what the article is talking about is opening a route from Rhylanor to Regina.

The jump-6 X-boat service mentioned in another newsbrief is essentially a rumor. Maybe there has been a decision by people in charge to get started right away, but then again, maybe they have just commisioned a feasibility study and 'TNS Staff writer' got it wrong. Never forget that the Imperium already has jump-6 news dissemination in the form of the 400T Navy Courier, so upgrading the X-boats to jump-6 would present a very small gain (jump-6 X-boats would be slightly faster than jump-6 couriers) for quite a big investment.

Overall? It would seem to me, that in light of all of this, perhaps the reason the drop tanks were not part and parcel of further Traveller products is because it was decided quietly by the powers that be at GDW, that drop tanks aren't perhaps all that viable. Perhaps no one could come up with viable rules to use in conjunction with the drop tanks, or perhaps they were busy with their normal activities and didn't spend a lot of time dwelling over the finer points that we are engaging in some 30+ years later

That's possible. Or perhaps they weren't mentioned again because no one has written an adventure where they would be part of the plot. I've always imagined that drop tank service requires a minimum level of traffic to be viable. Perhaps drop tank service is already muscling in on the traffic between the major worlds and we don't know because no one has written about it.

So, first mention of Drop tanks in the Fifth Frontier War rules indicate that in the spinward marches, they were being used/developed in 1105 (news release was dated 097 - 1105. By 201-1105, there were explosions at the manufacturing plant/assembly line, and by 186-1106, news (1 month late) was getting out about the tragedy and of the 217 lives lost in the accident.

The accident would give drop tank liners a tremendous negative PR in the Marches. Perhaps Tukera were forrced/chose to discontinue the Rhylanor-Regina service. Conceivably they might even have to stop the other services in the sector (Mora-Rhylanor, Mora-Trin, Trin-Glisten). But all we have evidence of is that they suspended the service to Regina pending the outcome of the official investigation into the accident. For all the evidence we have to the contrary, the service was resumed six months later.


Hans

 

[Hal]

The accident would give drop tank liners a tremendous negative PR in the Marches. Perhaps Tukera were forrced/chose to discontinue the Rhylanor-Regina service. Conceivably they might even have to stop the other services in the sector (Mora-Rhylanor, Mora-Trin, Trin-Glisten). But all we have evidence of is that they suspended the service to Regina pending the outcome of the official investigation into the accident. For all the evidence we have to the contrary, the service was resumed six months later.


Hans

As stipulated - there is nothing to state that the service wasn't subsequently resumed. But, and this is a big but...

JUMP Shadowing and all that crap (and I do consider certain changes in the game rules to be crap) started out as a casual mention here or there, and then picked up steam. Drop tanks for what ever reason, were casually mentioned here and/or there, but never seemed to pick up steam. With the exception of one classic Traveller reference to a drop tank design - I don't think there are many others, if any, showing that the concept at least, was popular with the original game designers. That is like saying "ok, Nuclear weapons exist and are used in profusion within the <insert game universe of choice here>" but then never again mention nuclear weapons for the next 20 years for that game system's life time. Just seems a wee bit odd is all.

 

[McPerth]

Likewise? A Meson Screen's ability to deflect incoming meson attacks is such that a modified 10+ is required to secure a hit against a ship with a Meson Screen Value 7 versus an E spinal Mount. If you assume a large hull (size Q+), with a +2 bonus to hit, and the target ship has an agility of say, 4, the final to hit would be:

4 (base to hit for D+ sized spinal mount)
-4 Agility of Targeted ship
+2 Size modifier for being Q+ in size
+2 Close Range
+0 (Computer difference: assuming both ships have the best computers possible)

(net result is an automatic hit, as the roll of a 2 is automatically modified by +4 to a 6 result - which is higher than the base to hit).

The hit is not automatic, you still need a 4+ to hit, as the positive modifiers are countered by agility (I guess you forgot to substract this modifier when saying the hit is automatic, even while you listed it in the modifiers).

I find that hard to swallow. Using drop tanks from a hull configuration 1, size 8 hull, would not work so well on a hull configuration 3, size B hull...

I guess most of the IN ships fall on a few classes, and if drop tanks were in mind when designing them (as I said several times mostly for interior moves), I guess making them adaptable (e.g. by modules of a fixed tonnage) would not be so hard, but that's an engineering problem, and so, out of my field. Others in this forum could answer you better than I can.

...If people are postulating that these add on hulls are available in large lots at various star ports, it would be an interesting logistical supply problem to determine how many of these drop tanks have to be prefabricated AND deployed on the off chance that they might be used by any given ship at any given time. For instance? Lets say that you want 100 of these drop tanks ready at any given time for 10 ships that can call at a given port at any given moment. Right then and there, the cost for these drop tanks are no longer negligable...

Maintaining the IN must be already a nightmare, and I don't think drop tanks would make it too worse. Comunications being so slow, I keep thinking most of IN actions must be with preplanned actions, and this preplanning may as well include drop tanks depots in key bases (maybe not in all, or at least not for every tipe of ship), but probably for courriers and the most common ships (assuming they are not adaptable to most ships).

Anyway, your reasoning could also apply to any spare parts, and I guess most of us assume the IN bases are well stored with them most of the time...

For courriers, not only do drop tanks allow to shorten the time between jumps, but they allow them to stop at empty hexes, allowing them to make its maximum advantage to jump 6 (allowing more jumps to be 6 than if they must adapt to existent planets). See my own example about reiforcing Jewell form Rylanor. http://www.travellerrpg.com/CotI/Discuss/showpost.php?p=363731&postcount=156

For the costs, I guess it would be less than those of missiles (I calculated about 3.75 MCr for a 50 bay nuke salvo, taking data from MT), and it is forfeited in CT and TCS...

...Now, lets look at this in another light. Each drop tank takes 10 weeks to manufacture. 100 drop tanks for 10 weeks apiece is not an inconsequential set up. Allocating production of say, 120 dton drop tanks for 10 weeks production time, would require roughly 12000 dtons of shipyard capacity.

And about the building capability for them, I guess in most Industrial worlds the shipyards are not usually running anyway close to their full capability. To build 5 times what you said, you only need the building capability for an AZL ship, and for quite less time...

You could dedicate the lower TL shipyards to it, as they use to need lower TLs than the ships proper, and keeping your ship production in higher TL ones (For Spindward Marches, let's say you keep Rylanor, Trin and Glisten building ships, while Regina, Efate and like worlds build the tanks).

At least, that is how I'd interpret the rules from Trillion Credit Squadron.

If I undertood well what I've read, TCS is not considered cannon in what budget and building capability refers.

 

[rancke]

JUMP Shadowing and all that crap (and I do consider certain changes in the game rules to be crap) started out as a casual mention here or there, and then picked up steam.

If you're talking about jump shadowing as being inside the solar jump limit, then that is explicit from Marc Miller's jumpspace article, but IMO it never picked up steam. I think system maps began showing the limit, but there were no rules to support using them. No tables showing how much extra time in real space it took to reach a mainworld orbiting in the life zone around this or that class of star, and no rules for increasing freight and passenger prices accordingly. And I don't recall any adventures or system descriptions that used jump shadows in any way, shape or form[*].

[*] Except one adventure I wrote for JTAS Online a few years ago that has now been overwritten by subsequently published material. ​

When jump masking was added (or as Marc Miller would apparently put it, its existence was made explicit (Marc says he always meant jump masking to be a feature of the jump process)), we did get some bare-bones rules for determining how much extra time jump masking/shadowing added to a jump, but it was never actually used for anything. No exploration of the varying transport costs inherent, no world writeups that explored seasonal traffic (more people would time their trips to a neighboring world to take place when both worlds were facing each other), no system writeups having space stations at the solar jump limit of worlds deep inside a jump shadow.

Drop tanks for what ever reason, were casually mentioned here and/or there, but never seemed to pick up steam. With the exception of one classic Traveller reference to a drop tank design - I don't think there are many others, if any, showing that the concept at least, was popular with the original game designers.

I think drop tanks simply aren't something the average free trader ever runs into, so adventures that are aimed at the average PC just don't have much opportunity to use them. Even the Gazelle doesn't actually use its drop taks routinely. It's just an added option for emergency use.

That is like saying "ok, Nuclear weapons exist and are used in profusion within the <insert game universe of choice here>" but then never again mention nuclear weapons for the next 20 years for that game system's life time. Just seems a wee bit odd is all.

Drop tanks are not said to be used in profusion in the OTU, which is the game universe of choice for official products..


Hans

 

[jshiggin]

JUMP Shadowing and all that crap (and I do consider certain changes in the game rules to be crap)

So, the 100 diameter limit applies to SOME celestial bodies, and not to others?

Why?

If you can't be within 100 diameters of a planet, why can you jump within, say, 30 diameters of the Sun? Note that 30 solar diameters is about the orbit of Mercury.

Note, by the by, that 100 diameters is probably a good thumbrule for rocky planets, not so much for stars or gas giants, due to differing densities.

Note further that Sol's density is higher than that of any of the gas giants orbiting same, so if the Sun doesn't prevent jumps within 100 diameters, there's not really a good reason to suppose that a gas giant will either. Contrariwise, if a gas giant has a meaningful 100 diameter limit, the Sun will too.

Note that the main reason that Jump-shadowing never really took off is that it's a pain in the ass to use - you have to keep track of orbital positions of any world that your PC's (or your bad guys) visit forever after.

On the other hand, Jump-shadowing adds some interesting twists that actually help things work as intended. There are worlds in Trav that no sane person would ever visit (unless the GM forced them to at gun point). BUT...if you can only get from where you are to where you want to be by flying halfway round the solar system (the jumping and flying halfway around THAT solar system), or jumping to some hellhole that's accessible from here and there both (right now - in two months, it'll be shadowed from you too, and some other hellhole will be the only intermediate stop between here and your goal)....

Plus, jump=shadowing gives new life to piracy. There will be some stars that are large enough that the mainworld is within the 100 diameter limit of the star. Which means a lot more normal space travel to get to/from that world, hence more opportunities for a pirate to catch you well away from local defenses.

 

[77topaz]

Plus, jump=shadowing gives new life to piracy. There will be some stars that are large enough that the mainworld is within the 100 diameter limit of the star. Which means a lot more normal space travel to get to/from that world, hence more opportunities for a pirate to catch you well away from local defenses.

Some stars? A lot more than some, I'd say. There was a thread on here just a few weeks back which showed that for about three worlds in the Spinward Marches which would require 66 days travel from the jump point to the planet (consult the thread for the G-rating used and accurate stats), and about 60 with more than a day, including Glisten (and probably some other major worlds - Rhylanor too, I think, and/or Mora).

 

[Hal]

Some stars? A lot more than some, I'd say. There was a thread on here just a few weeks back which showed that for about three worlds in the Spinward Marches which would require 66 days travel from the jump point to the planet (consult the thread for the G-rating used and accurate stats), and about 60 with more than a day, including Glisten (and probably some other major worlds - Rhylanor too, I think, and/or Mora).

I din't have issues with Jump MASKING, which takes into account whether or not a ship is within 100 diameters of a star. I consider a star to be no different than a gas giant when it comes to the rule of jumping within 10 diameters of a star, or within 100 diameters of a star, etc.

Jump Shadowing on the other hand, is that little bitty thing saying that a ship precipitates out of jump space, if there is a mass between it and its planned exit into normal space (ie its destination). The original rules did not say that a star between a ship and its planned exit, forced the ship back into normal space 100 diameters from the mass. The newer rules for the fifth generation of Traveller seem to permit even SHIPS to cause problems when jumping - something that the earlier rules did not.

Star Wars had it such that you could be precipitated out of hyperspace if there was a mass or some interdiction ship at the right place or right time - forcing the ship out of its faster than light activity. But the way it works now? It pretty much is an alien beastie from the original incarnations of Traveller such as CT, MG, or even T4. GURPS TRAVELLER and other versions that incorporate Jump Masking, bug the heck out of me.

Mind you, I'm a GURPS FAN and all that, but the rules for entering into jump do NOT reflect the practices of say, CT or MT. Think about it. A skill 12 in GURPS (or any 3d6 game system) has a roughly 74% chance of success. Having to roll three successive skill rolls against a skill 12 for instance, does not imply that the ship has a 74% of successfully entering Jump space, but instead, has a FAR lower chance of success of entering Jump Space. Statistically speaking, the odds of rolling three successful rolls in a row, is equal to the odds of success for the first roll times the odds of success for the second roll, times the odds of success for the third roll. So. Having a pilot with skill 12, a navigator with skill 12, and an engineer with a skill of 12, all combined, only have a roughly 40% chance of taking their ship into jump space without problems.

.74 x .74 x .74 = .405224

So, do I have a problem with how GURPS changed the game mechanics to where it is vastly different than the classic Traveller rules? You betcha. As GM, do I bother with having to make a piloting roll to engage the jump drive properly? Not really (only thing I'm interested in is whether or not the player rolls a crit failure). Do I bother with the navigation roll? Yes, but not to enter into jump space proper (Classic Traveller never had rules for entering into jump space and hitting your destination properly - which is a shame actually. For me, navigation failures mean you don't go where you expected to - but in the age of computers, you'd think that exiting jump space midway between two stars would be hard to mess up no?) As for the engineer's roll? I can see that to a large extent simply because Mis-jumps occurring - tended to occur for one of two reasons:

Raw fuel

or

Lack of proper maintenance where you start having a chance of misjump after missing your annual maintenance

So:

Jump Masking - GOOD. Really no different than trying to jump near a gas giant. Not really a "change of rules" per se - but making data on star diameters available so that GM's may know what is or is not viable jump distances from a star.

Jump Shadow - BAD. Same concept as used in Star Wars, but was never part of the original Traveller Universe until at least after T4.

 

[rancke]

I din't have issues with Jump MASKING, which takes into account whether or not a ship is within 100 diameters of a star. I consider a star to be no different than a gas giant when it comes to the rule of jumping within 10 diameters of a star, or within 100 diameters of a star, etc.

Jump Shadowing on the other hand, is that little bitty thing saying that a ship precipitates out of jump space, if there is a mass between it and its planned exit into normal space (ie its destination).

Other way around. If a world is inside a jump limit, it is in the jump shadow of the body that generates the limit. If there's a jump shadow in between a ship and its destination, the destination is masked from the ship even though the destination is not in a jump shadow.

The original rules did not say that a star between a ship and its planned exit, forced the ship back into normal space 100 diameters from the mass.

No indeed. Marc Miller says that was how he envisaged it all along, but I never got that impression myself from the rules nor the setting details.

The thing is, solar jump limits are implicit in the rules and quite explicit from Marc Miller's jumpspace article, yet there is no explicit mention of solar jump limits in any of those early rules or setting material either. (Except that I think solar jump limits were included in system maps made after the article was printed. Be that as it may, solar jump limits were never used in any way, shape, or form any more than jump masking was).


Hans

 

[Hal]

Some stars? A lot more than some, I'd say. There was a thread on here just a few weeks back which showed that for about three worlds in the Spinward Marches which would require 66 days travel from the jump point to the planet (consult the thread for the G-rating used and accurate stats), and about 60 with more than a day, including Glisten (and probably some other major worlds - Rhylanor too, I think, and/or Mora).

The "Piracy Issue" could have been handled a lot better than it was - I'll admit. But that could just as easily have been rectified by changing the game rules regarding Jump distances itself. One of Marc Miller's articles on Jump accuracy indicated that it was dependent upon the actual distance being jumped, as to how far the "miss" could be as far as astrogation was concerned. The pertinent phraseology is:

"Over a jump distance of one parsec, the arrival point of a ship can be predicted to within perhaps 3,000 kilometers (on larger jumps, the potential error is proportionally larger). Error in arrival location is also affected by the quality of drive tuning and by the accuracy of the computer controlling the jump; these factors can increase jump error by a factor of 10.
"

(Note: this is from an article by Marc Miller published in the SJGames online JTAS. )

What was written above, may be the only reference that Marc Miller ever published regarding how accurate navigation can be. If there are other references, I'd be happy to look at them, but for now, that is all I have to go on, and since it is from SJGames era of publishing, I'm not entirely certain how others might view its "canon" application.

In any event - Jumping with drop tanks is something that should have been made part of the common ship designs subsequent to the introduction of the information regarding drop tanks. That we never saw it be applied, is puzzling to say the least. That people want to experiment with the concept is fine by me.

As for myself? I've noted that in the earlier Traveller rules, using "raw unrefined fuel" used to be a common concept. Going for wilderness refueling as also a common thing. Subsequent rule sets sort of paid lip service to that, but with GURPS FAR TRADER - it became very evident that in order to shorten the time spent jumping from world to world - the time spent getting raw unrefined fuel was more costly in the long run than the cost of the fuel itself.

Ah well - I should quit while I'm not too far behind

 

[Hal]

Other way around. If a world is inside a jump limit, it is in the jump shadow of the body that generates the limit. If there's a jump shadow in between a ship and its destination, the destination is masked from the ship even though the destination is not in a jump shadow.


Hans

Yup - I always tend to confuse the two, but the concepts I never get confused So, you're right, its' masking is a mass between two jump points blocks the jump, while jump shadow is the issue of being inside a star's 100 diameter radius. Like I said, there's no real difference in my mind's eye between a star and a gas giant (other than the star is more massive and is burning!) and as such, should be held to the same rules as gas giants (which in turn is held to the same standards as planetary bodies).

Jumping "Through" a mass and its 100 diameter limit was never an issue or even alluded to in earlier games - so as a retcon after the fact, I find it obnoxious. Retconning that even ships within 100 diameters of another ship - is even more obnoxious in my eyes. It is one reason why I'll not likely play the fifth edition of the rules.

See, here's my beef:

When you build a game universe, and the game mechanics imply a given aspect of said universe, that is just how it works. If however, your game mechanics contradict the so called "history of said universe", then there is a problem. What is worse however, is when the history works under the original game mechanics, and then is retconned in a manner as to invalidate the history of the game universe under the original rules - then something is wrong. It is one reason why I'll never GM the Interstellar wars time period using the rules from SJGames. I find it on par with being forced to wear a skirt when I've worn pants all my life - and no, I don't have issues with Kilts, but until I'm in Scotland or with a bunch of guys wearing scotish uniforms that require kilts, I'm not likely going to wear kilts either

 

[far-trader]

...

"Over a jump distance of one parsec, the arrival point of a ship can be predicted to within perhaps 3,000 kilometers (on larger jumps, the potential error is proportionally larger). Error in arrival location is also affected by the quality of drive tuning and by the accuracy of the computer controlling the jump; these factors can increase jump error by a factor of 10.
"

(Note: this is from an article by Marc Miller published in the SJGames online JTAS. )

What was written above, may be the only reference that Marc Miller ever published regarding how accurate navigation can be. If there are other references, I'd be happy to look at them, but for now, that is all I have to go on, and since it is from SJGames era of publishing, I'm not entirely certain how others might view its "canon" application.

If I recall correctly that is pretty much verbatim from the article Marc wrote for JTAS print for CT. I recall it being spelled out more specifically as 3,000km per parsec jumped rather than simply "proportionally" and I don't recall the bit about computer or drive tuning influencing the error.

 

[mike wightman]

It is one reason why I'll never GM the Interstellar wars time period using the rules from SJGames. I find it on par with being forced to wear a skirt when I've worn pants all my life - and no, I don't have issues with Kilts, but until I'm in Scotland or with a bunch of guys wearing scotish uniforms that require kilts, I'm not likely going to wear kilts either

This I don't understand. I think SJG did a fantastic job with GT:ISW.

What is in it you find off-putting?


The rules for jumping between systems and no empty hex jumps are a direct result of the OTU historical information.

 

[mike wightman]

If I recall correctly that is pretty much verbatim from the article Marc wrote for JTAS print for CT. I recall it being spelled out more specifically as 3,000km per parsec jumped rather than simply "proportionally" and I don't recall the bit about computer or drive tuning influencing the error.

Perhaps MWM added or revised a bit of his JTAS article for the SJG online version?

I'll have to go find it and check.

 

[Hal]

This I don't understand. I think SJG did a fantastic job with GT:ISW.

What is in it you find off-putting?


The rules for jumping between systems and no empty hex jumps are a direct result of the OTU historical information.

Cite for that? To the best of my knowledge, there is nothing to support the notion that one could not jump into empty space, and in fact, contradicts the rules that predated SJGames effort at Interstellar Wars by a LONG margin of time (to wit: The Traveller Adventure and the fact that jumps in Traveller do NOT require that the ship exit jump space near a gravitational source. Even misjumps permit a ship to end up in a hex that does not contain a star in it). Also, it invalidates the concepts that were used in T4's rules as well for Mileu Zero.

In any event - if people are happy to use that game, I'd say "go for it". It's just not for me. <shrug>

 

[mike wightman]

The board games Imperium (the Interstellar Wars era itself) and Dark Nebula (Terrans vs Aslan) are both considered canon for the OTU and both describe historical periods during which empty hex jumps were not possible.

In order to preserve this canon history the designers at SJG had to preclude empty hex jumps.

In fact it is in the technology development rules of the Dark Nebula game that empty hex jumps become a possibility.

 

[McPerth]

This I don't understand. I think SJG did a fantastic job with GT:ISW.

What is in it you find off-putting?

The rules for jumping between systems and no empty hex jumps are a direct result of the OTU historical information.

First of all, I must state I've never put my eyes on GT (I had no opportunity, not any bias against it).

This said, jumping to empty hexes has many canon precedents, AFAIK:

-The IISS maintains some contact (no matter how sporadic) with the islands Cluster, and that needs to jump into empty hexes.

-In Aslan Alien Module (CT), it's told that the J5 gap in the rift was first crossed exactly that way before J5 became available. They left caches of fuel in mid space to refuel and make the two jumps needed to cross the rift.

-Challenge (MT, sorry, I cannot give exact reference) talks about Margaret building a deep space refueling station to open a trade route with the Hivers. I think that would need jumping to empty hex to set it up, and its only use would be for ships jumping there to refuel (also into an empty hex).

-There are some references (sorry, no exact reference again) about deep space refueling bases in the Rift for fast courriers. Same as above.

-In Darrian Alien Module (also CT), it's told its TL 16 fleet is based on a slow moving rogue comet also in an empty hex. While this is not exactly jumping in the middle of nowhere, as previous references, neither is that jumping to a system, and I see it closer to jumping into empty hex.

And sure I forget (or just don't know) many other references about it.

 

[mike wightman]

Of course empty hex jumps are canon - first mention is actually A3 Twilight's peak - during the 3rd Imperium OTU...

BUT

it is also canonical that during the ISW through to DN historical era such empty hex jumps were not possible for Vilani or Solomani or Aslan ships.