Synchronized Jumps

[Belisknar]

"To synchronise a jump, every ship taking part must have a crew member succeed at a Difficult (10+) Engineer jump drive) check (1D rounds, INT or EDU). If one ship fails in this check, then it may not join in the synchronised jump. If this happens, the admiral may choose to jump without it or give the order for every ship to make the check again, restarting the whole process.

Synchronised jumps use the same Jump Control software as normal jumps, but the software package will require an extra +5 Bandwidth on top of its usual demands."

While I like the idea,

If one ship fails in this check, then it may not join in the synchronised jump. If this happens, the admiral may choose to jump without it or give the order for every ship to make the check again

Despite the vagueries of how JUmp works we know that there are still many variables that will kick in reguardless of how much you sychronize the jump. There are many things that can go wrong during the jump sequence so giving the Admiral the option to call for all the ships to Mulligan the roll if one or any ships fail seems like a bit of an easy out. Especially since characters aren't supposed to know if they do or don't fail until the results of their roll kick in and the result of a jump roll isn't apparent until after the jump happens.

The only thing that the Admiral can guarantee will be the same across the fleet will be the Astrogation calcutaions as likely his ship would be the one doing and then it would be passed throughout the fleet that way.

 

[Galadrion]

There are actually multiple factors involved in the decision about whether or not convoys will form.

First, do the ships' captains/owners perceive a need for the protection of a convoy? If not - if there isn't enough piracy or other trouble in the area to make the decision-makers that concerned - then those decision-makers aren't going to bother with the inconvenience of coordinating with other.

Second, how much inconvenience for those captains/owners is involved? If there's a common authority they can take advantage of - Naval Liaison Office, corporate services office, or some similar such - then convoys will be easier to organize and thus more common. If the captains involved have to do the legwork and organization themselves, it's going to be less attractive - and besides, who gets to take the lead and/or make the decisions? And who gets stuck herding all these cats?

Third, does the volume of traffic support convoys? If you're talking about a major trade route between two Class A starports at a pair of highly-developed worlds, you're probably talking about a large number of ships making those jumps daily, so the traffic is there. But between backwater world (where the tramp freighters are more likely to be the dominant traffic), you can be talking about "routes" which average one or two ships a week, or less. Is it really likely that a tramp captain is going to hold at a port for, say, a month waiting for enough others wanting to make the same jump in order to be part of a convoy? Or is he likely to take the chance?

Now, I do think that there will likely be scenarios where civilians will take advantage of the synchronize jump techniques. Rather than putting together a convoy to go to a dangerous, low-traffic system, a tramp captain who doesn't feel that his own ship's armaments are sufficient might look into hiring a mercenary escort - the expense is likely to make sure that this isn't exactly a common circumstance, but for a sufficiently lucrative run, it becomes an option.

And that last paragraph introduces another possible campaign - gunboats for hire. The players can become a mercenary starship escort troupe, hiring on as convoy protection and (eventually) getting into the business of organizing and quartermastering their own convoys. I'm sure than the experienced game-masters here are already starting to see a number of adventure possibilities...

 

[phavoc]

I didn't mean to imply that misjump was common. Even a tiny chance would upset the starship model. But a microscopic chance of misjump still remains.

Agreed. Much like things today are if you try to skirt the edge of whatever it is you are doing you run a real risk. Plus there are still risks in general.

I may have used an overzealous interpretation of the "jump time is random" texts.

To be fair I don't think your explanation was overzealous.

The duration of a jump is fixed at the instant that jump begins, and depends on the specific jump space entered, the energy input into the system, and on other factors. In most cases, jump will last a week. JTAS 24, p36, "Jumpspace"

To jump, a ship creates a bubble of hyperspace by means of injecting high-energy exotic particles into an artificial singularity. The singularity is driven out of our universe, creating a tiny parallel universe which is then blown up like a balloon by injecting hydrogen into it. The jump bubble is folded around the ship, carrying it into the little pocket universe.

MgT2 Core, p148.

I have not formalised this, but I have interpreted this along the lines "each jump is unique, each duration is random". I agree that it is not very well defined.

Yes, the basics of jump travel - or at least the MGT version from v1 when it came out and diverged from established canon (anybody need a good deal on Zuchai crystals or lanthanum??). But what I was referring to was more along the lines of write ups going beyond the standard explanation and helping to better define the issue. The only thing I can think of is the Miller article you listed there.

There is no "complete stop" in space. There is no absolute movement, only relative movement, and hence speed. You can be stationary relative a nearby planet (probably requiring acceleration to remain so) but still moving relative the local star, or nearby stars. The star systems you are jumping from and to are likely to move quite rapidly relative each other, so even if you are not moving relative the origin star, you are moving relative the target star.

That's very true. In space relative is a relative term. Do you want to hold your position relative to the other ship you are going to be jumping with, the planet you just departed from, the local star, the star in your arrival system, the cluster of stars you are in, or even the galaxies core? I wasn't specific because I had just made that up on the fly. I would suspect if you limited it to complete stop relative to your ship and the local star would be as good a rule of thumb as any. Millers' article did, if I recall correctly, mention that star systems could affect the relative velocity of your travel.

Not that there are not problems, but I have never seen that as much of a problem. The spaceport classification tells us that certain services are available, but generally nothing of the scale of the operation, it might be built to handle a handful, or perhaps a few hundred, departures a day. Class A or B generally means that there is a shipyard in the system, but tells us nothing about how large ships, or how many ships, can be build or serviced locally.

Class A starports are major facilities, at least as defined in the Starport books. The Starport books are more guidelines, which is good, but it makes no economic sense to establish all the necessary infrastructure and industry to support a shipyard capable of building star faring vessels without enough volume to justify its' existence - unless somebody is subsidizing them. In that case all the rules are out the window.

 

[phavoc]

For the record I'm not trying to troll anyone here. All I'm looking for is a reasonable explanation that makes sense and fits within the gaming setting. If military ships can do it, then anyone should be able to do it. If it's impossible, then it's impossible for all types of ships.

 

[Reynard]

It's not impossible. It's usually very expensive and to commercial ventures nothing else matters.

 

[Condottiere]

1. Jump tapes.

2.

 

[AnotherDilbert]

All I'm looking for is a reasonable explanation that makes sense and fits within the gaming setting. If military ships can do it, then anyone should be able to do it. If it's impossible, then it's impossible for all types of ships.

It's possible, but difficult. If it's easier for military ships, it's just that I assumed the Navy is a bit fanatical about squeezing the most out of their crews. Even a destroyer has tens of engineers, presumably it has a competent Jump engineer. I'm also assuming that the Navy can spend some money on augmenting the guy who initiates jump on a warship worth billions. Hence I'm assuming most warships have pretty good skills. The same cannot be said for a para-military Type T.

For a Free Trader on the other hand with a single engineer, probably not specialised in Jump the average skill level is lower.

My calculations are built on a large pile of loose assumptions, you might want to call it "best case" and "reasonable case" instead.

Class A starports are major facilities, at least as defined in the Starport books. The Starport books are more guidelines, which is good, but it makes no economic sense to establish all the necessary infrastructure and industry to support a shipyard capable of building star faring vessels without enough volume to justify its' existence - unless somebody is subsidizing them. In that case all the rules are out the window.

A little travel and limited trade multiplied by 18 trillion people in the Imperium still means a lot of starships jumping around.

Let's make a quick estimate:
The Imperium has a pop of 18 trillion and a GDP of 140 PCr. If we assume 0,1% of the economy is building ships (probably too high?) that is 140 TCr worth of ships every year. If each ship is used for 40 years that is a total amount of 5600 TCr worth of active ships. If we assume a 10000 dT J3 freighter carrying 100 passengers and 5000 dT cargo costing MCr 2400 as average, that is about 2 million active merchant ships.

Each ship does 30 jumps per year, so that makes 60 million jumps with 6 billion passengers and 300 billion dT cargo carried.

A current major airport carries tens of millions of passengers per year, so the Imperium would have hundreds of starports as busy as current airports.

So as a quick estimate a stellar tech pop A world have a starport as busy as a major airport. Note that most of the Imperial population lives on such worlds.
A pop 6 world would have a much, much less busy starport, unless it's on a major trade route between pop A worlds.

 

[rust2]

A current major airport carries tens of millions of passengers per year, so the Imperium would have hundreds of starports as busy as current airports.

I doubt that, mostly because the average starship passage in the Third Imperium is a lot more expensive than the average airline ticket today and because a round trip with a starship takes at least two weeks instead of a couple of hours, probably too long for a normal holiday trip to the beach. Therefore the actual number of passengers able to afford a passage and with enough spare time to spend two weeks on a starship should be considerably lower than the number of airline passengers today.

 

[AnotherDilbert]

I doubt that, mostly because the average starship passage in the Third Imperium is a lot more expensive than the average airline ticket today ...

I agree that the average Imperial subject cannot afford Interstellar travel. In my quick estimate above such a busy starport would service a system with tens of billions of sophonts, instead of perhaps ten millions today. So Interstellar travel would be thousands of times less common than modern air travel.

 

[phavoc]

It's possible, but difficult. If it's easier for military ships, it's just that I assumed the Navy is a bit fanatical about squeezing the most out of their crews. Even a destroyer has tens of engineers, presumably it has a competent Jump engineer. I'm also assuming that the Navy can spend some money on augmenting the guy who initiates jump on a warship worth billions. Hence I'm assuming most warships have pretty good skills. The same cannot be said for a para-military Type T.

For a Free Trader on the other hand with a single engineer, probably not specialised in Jump the average skill level is lower.

My calculations are built on a large pile of loose assumptions, you might want to call it "best case" and "reasonable case" instead.

I get that. But the rules provide no real differentiation between military and civilian. So that merchie engineer is just as qualified as the military one. That Free Trader has just as good targeting software as the dreadnought, and that daredevil liner pilot is just as good as the one flying the heavy cruiser. So in this sense there is no real difference between military and civilian ships. Some of the designs for the military ones have zero armor cruisers. That's, well, silly.

Which leads me back to the point of if it's possible and common for military ships, then it must be possible (and less common) for civilian ones.

Let's make a quick estimate:
The Imperium has a pop of 18 trillion and a GDP of 140 PCr. If we assume 0,1% of the economy is building ships (probably too high?) that is 140 TCr worth of ships every year. If each ship is used for 40 years that is a total amount of 5600 TCr worth of active ships. If we assume a 10000 dT J3 freighter carrying 100 passengers and 5000 dT cargo costing MCr 2400 as average, that is about 2 million active merchant ships.

Each ship does 30 jumps per year, so that makes 60 million jumps with 6 billion passengers and 300 billion dT cargo carried.

A current major airport carries tens of millions of passengers per year, so the Imperium would have hundreds of starports as busy as current airports.

So as a quick estimate a stellar tech pop A world have a starport as busy as a major airport. Note that most of the Imperial population lives on such worlds.
A pop 6 world would have a much, much less busy starport, unless it's on a major trade route between pop A worlds.

I think those numbers are way too low. Multiple planets with populations in the billions will drive far more travel. And also you need to think about how the world's flying statistics are taken into account. According to IATA, the African subcontinent is woefully under-developed as far as air travel is concerned. But it's starting to catch up. And the two most populous countries, India and China, still have really anemic air travel industries for their size. And part of that is because the population is poorer than the average European or American, and also because of the population density it's easier and cheaper to use trains to move people (not to mention they still are building out credible aviation infrastructure).

And that begets the question, should we use the US/Europe and the western world for the example of what the Imperium is supposed to operate as? More likely the Imperium would be the same as Earth is. But the inelastic pricing model of both freight and passenger service for the game precludes using real world economic theory. If the cost of moving freight and passengers is so prohibitive, then you simply wouldn't seen the amount of interstellar traffic the game posits. Instead star systems would develop system-wide infrastructure and shuttle passengers and cargo INTRAsystem. With the technology of the Imperium, it would take a civilization a LONG time to exhaust the minerals of an entire star system. And with modern recycling tech you wouldn't need to consume as much either.

But that's reality, and I'm not wanting to play a fully reality-based Traveller game (taxes, piles.... ugh!). Still, I want the game model to make at least moderate sense, mostly because if I'm going to referee it, or play in it, I want to be able to dissasemble the rules so I know how the characters will and can accomplish things. It's no fun to be a corporate spy and find the computers are unencrypted and front door unlocked. It's also not realistic to have 50 guards surrounding the chairman's 13th removed cousin who knows the secret recipe that the players have been hired to steal. Or, in this argument, having to pay Cr2,500/ton for cargo space and Cr8,000 for a tiny room for a week on a tramp freighter that just showed up in the system and happens to be heading in the direction I'm traveling.

 

[Reynard]

"I get that. But the rules provide no real differentiation between military and civilian. So that merchie engineer is just as qualified as the military one. That Free Trader has just as good targeting software as the dreadnought, and that daredevil liner pilot is just as good as the one flying the heavy cruiser"

I know I'm invoking "In Real Life" again. I think it's more common for militaries to have the means and resources to put the right people in the right place whereas commercial ventures are far more willing to use the cheapest that gets the job done. Player characters would be the exception of course and should never be viewed as baseline for everyone else. That's why you don't see sea freighters armed and running with the best or even good crews in African pirate infested areas. The engineers on a destroyer or carrier are there by their merit because it's extremely important the ship does not fail.

If a mega-corp has financed a convoy fleet meant to be synchronized, there is something Very important to justify the expense and organization close to military level. That's when they also sink money to hire the best Chief engineer on each ship. It also means some very rare and important event created the need and not just Round up the Wagons.

Oh and being a merchie engineer doesn't automatically make you an outstanding engineer just willing to be hired on and the galaxy doesn't suddenly concentrate all high skilled merchie engineers in the same place, that's TIME and MONEY to do that. Militaries are often better at sending resources where they're needed and do it from a larger pool of candidates. I am almost assuring the dreadnought trained gunner running taxpayer financed software on a taxpayer installed computer will win even if only firing the exact same turret configuration rather than the Free Trader who must try to scrape up the Credits over months or, realistically, years for the same software and possibly a computer upgrade to hold it and their regular software simultaneously. Of course a 'daredevil liner pilot' will be as good or possibly better but they are, by definition, the rarest of the rare (i.e., player characters). The military pilot has a chance to be as good or better because the military has vast recruiting and training abilities. They take the Navy Career generator and pump out a LOT of characters then decide who goes where with the worst getting KP duty. Commercial outfits, except for their most important ships, will draw from the average NPCs pools. The number of NPCs for a needed career are created and most will be average and one may be above average but they all have to be used. Only one liner gets the good one again to save money.

The rules don't provide (yet) such differentiation but some people, and it seem especially on forums, then interpret it as in their favor. I've seen some Traveller games list the grade of unit skill such as Azanti High Lightning and Striker which often is a good indicator how they interpret military composition and why. For the most part, Mongoose give rules to create careers. It is the ref's job to determine what is needed to populate an exciting and reasonable story. Navies are naturally huge and resourceful and awesome whether a flotilla or a fleet. Pirate 'fleets' are only awesome because there are two or three ships against the players' one ship even if the pirates have lousy crews.

 

[Reynard]

"I think those numbers are way too low. Multiple planets with populations in the billions will drive far more travel."

I think 4th edition has a means to determine planetary ship traffic, possibly Pocket Empires. I know T5 has the formula and it doesn't show cinematic levels sometimes even for more favorable worlds on the average. Look at sector and subsector maps. High population, Class A/B ports and great trade codes don't rule the universe. The trade routes are not so common either based on the rules and much of a region can be mediocre to ship travel. High traffic area are exception and probably famous. Thing is, most people in the real world may never visit an airport, seaport or even rail stations but imagine they all huge, crowded 24/7 and gloriously... busy. I'm sure the vast majority of planetary populations have imaginary expectations of starports too.

 

[phavoc]

I agree with you. Traveller rules lump everybody together, and in most of the games I've played, all the adventurers were almost always ex-military. In reality that wouldn't be the norm.

In other games, like Starfire, crew quality did affect combat because a crack crew would typically eat the lunch of a green one, barring a number of just terrible dice rolls.

While I don't see large numbers of merchants traveling in convoys, I definitely see ships traveling groups of twos or threes. Say there is patron who needs to transport some people and cargo to an outsystem planet (the set of ships consist of 2 free traders and a subsidized liner). And because there is a small corp to corp war going on, the company decides to provide a couple of Gazelle's as escorts. That's 5 ships that need to travel together and jump/arrive together. And they are all civilian. In the Traveller universe it's not unheard of. Especially since megacorps will routinely engage in shenanigans against rivals and annoying planetary authorities to bring credits to the bottom line.

That's just one scenario. You may also have a couple of Free traders that decided to travel together for protection and to be able to pick up potentially better cargo rates. Or say you have the King Richard that is a luxury liner (since travel is apparently only for the wealthy), and because of it's passenger list it always travels with escorts. In that case the ships always need to be able to jump and arrive as a group.

And that's why I'm very much for any ship being able to synch their jump with others outside of war or convoys.

 

[phavoc]

"I think those numbers are way too low. Multiple planets with populations in the billions will drive far more travel."

I think 4th edition has a means to determine planetary ship traffic, possibly Pocket Empires. I know T5 has the formula and it doesn't show cinematic levels sometimes even for more favorable worlds on the average. Look at sector and subsector maps. High population, Class A/B ports and great trade codes don't rule the universe. The trade routes are not so common either based on the rules and much of a region can be mediocre to ship travel. High traffic area are exception and probably famous. Thing is, most people in the real world may never visit an airport, seaport or even rail stations but imagine they all huge, crowded 24/7 and gloriously... busy. I'm sure the vast majority of planetary populations have imaginary expectations of starports too.

Well, I can't say what the future will hold, but I can relate to the present. I live in Dallas, TX and from my window at work I see the constant lines of aircraft coming in to land at DFW. Using the 2015 numbers, it's the 3rd busiest airport in the world by aircraft movements and the 10th busiest in the world for passengers. Last year 64 million people arrived or left DFW. That's about 20 times the population of the DFW area.

So the busiest airports in the world for aircraft movements - https://en.wikipedia.org/wiki/List_of_busiest_airports_by_aircraft_movements#2015_statistics

Atlanta is number one with 874,000 movements.

The busiest by passengers - https://en.wikipedia.org/wiki/List_of_busiest_airports_by_passenger_traffic#2015_statistics

Atlanta tops again, with 100 million passengers coming through the airport.

Which is why I tend to think the models that Traveller is using are probably underestimating the amount of travel. Though this goes back to another point - what era of human history is Traveller trying to mimic? To me it seems like it's more of the turn of the century (early 1900s), which was the era of the big gunned battleship and fast passenger liners.

 

[AnotherDilbert]

US GDP / capita: ~$55000
Cheap airline return ticket: ~$200

Imperial GDP / capita: ~Cr7500
Cheap interstellar return ticket: ~Cr12000

Modern air traffic is not comparable to Traveller interstellar traffic. How many americans take month-long trips that cost $100000? Some do, most don't.

The assumptions built into the OTU gives rather sparse traffic. If you want more traffic you have to make the Imperium a lot more affluent, or starships a lot cheaper.

 

[Reynard]

"And that's why I'm very much for any ship being able to synch their jump with others outside of war or convoys."

And I agree IF they have the capital, resources and especially a reason but they will always be the exception and never the rule. There has to be a NEED to use those resources not just it's possible. Unfortunately, players too often think money is no object so everything is maxed out. Normally though, every Credit spent unnecessarily is a Credit lost. What is exceptionally deadly out there in the direction you need to go that justifies those incredible actions? Player paranoia is not a good reason.

 

[phavoc]

US GDP / capita: ~$55000
Cheap airline return ticket: ~$200

Imperial GDP / capita: ~Cr7500
Cheap interstellar return ticket: ~Cr12000

Modern air traffic is not comparable to Traveller interstellar traffic. How many americans take month-long trips that cost $100000? Some do, most don't.

The assumptions built into the OTU gives rather sparse traffic. If you want more traffic you have to make the Imperium a lot more affluent, or starships a lot cheaper.

No, it's not because the Traveller economic system isn't realistic. Ticket prices that do not vary, freight rates that don't vary, money that is universal and has the same value regardless of the local economy.

Which is why I question the underlying assumptions it's built upon. Because they couldn't exist in reality.

 

[phavoc]

"And that's why I'm very much for any ship being able to synch their jump with others outside of war or convoys."

And I agree IF they have the capital, resources and especially a reason but they will always be the exception and never the rule. There has to be a NEED to use those resources not just it's possible. Unfortunately, players too often think money is no object so everything is maxed out. Normally though, every Credit spent unnecessarily is a Credit lost. What is exceptionally deadly out there in the direction you need to go that justifies those incredible actions? Player paranoia is not a good reason.

Where in the example is there a need for capital resources? The examples I pointed out are nothing special. The need is there, as stated. My examples are meant to show need without special tech or economics being involved.

So I'm scratching my head a bit to understand what you are trying to say here.

 

[Condottiere]

1. You don't need convoys in the middle of the Imperium, even in wartime, unless it's a civil war or the enemy has managed to deeply pentrate with their commerce raiders.

2. Spacefarer traffic depends on population, since a certain percentage will have the means to become tourists, and another demographic will have their travel subsidized by military, bureaucratic, or commercial institutions.

 

[AnotherDilbert]

US GDP / capita: ~$55000
Cheap airline return ticket: ~$200

Imperial GDP / capita: ~Cr7500
Cheap interstellar return ticket: ~Cr12000

No, it's not because the Traveller economic system isn't realistic. Ticket prices that do not vary, freight rates that don't vary, money that is universal and has the same value regardless of the local economy.

That is just a simplification. High freight prices are a necessary consequence of expensive starships.

Which is why I question the underlying assumptions it's built upon. Because they couldn't exist in reality.

I fear I do not understand you.

Assumption A: People are poor.
Assumption B: Ships are expensive.
Consequence: Travel is too expensive for normal people.
Which part couldn't exist in reality?
Could 18th century Britain not exist in reality?