X-Boat Launch Stations

[aramis]

To maintain a daily trip, on a given linkage (remembering that only about 10% of worlds are actually linked by X-boat - hans, check the canonical maps; no line, no X-boats)...

on a given day, a single XMail linkage has...

Category	Hulls XB	Hulls XT
Ready @ A	1	1*
Ready to go @ B	1	1*
Traveling A to B	7 †§	0
Traveling B to A	7 †§	0
Spare in case of delay @ A	1§	0
Spare in case of delay @ B	1§	0
In maintenance‡	1	1/3**
	19	2§

[tc=3] [/tc]

* may be shared with other links, but only if they can target the same side of the system. Limited severely by the temporal fluctuation more than the physical fluctuation of exit.
** 1 per 3 systems allows annual maintenance and transit times for shuffling XT's to cover AM. Most XTs can be maintained in system, but you still have to cover the week downtime.
† 6-8 on any given day, nominally 7. Hence the requirement for spares for delay.
‡ Remember: annual maintenance nominally takes 2 weeks, so 1 per 26. You can probably push it out to 1 per 30, but don't really want to do that.
§ If running multiple trips per day, these need to be multiplied by that rate.

A daily X-boat is thus about 19 XB's and 2-3 XT's.

The thing about the XT is that while one can cover a good amount of space, its fuel stores aren't that big, and if it is shared between 2 or more links, they must needs be aiming for the same target spot so that it can get to them in a timely manner.

Also, keep in mind that about 3% of jumps go awry. In MT, MGT, TNE, and T4, they're normally outside the target window in time, and often in space. So you need an extra XT in system to go fetch the lost ships. And you cannot tell the incoming XB's to switch target points...

Assuming worst case - MT -
Once you get to 2 a day, once a month you are fetching one from out in the system. Once you get to 4 a day, you're losing one a year (random interstellar location), and fetching 2 a month from well away from the world.

 

[boomslang]

Aramis:

I am seeing a scheduling issue, however.

If using the common 168 hours ± 10% formula for Jump duration, any given "scheduled" outbound Xboat will in practice have a 33.6-hour departure window. You can tentatively schedule them for daily departures, but what do you do operationally when one Xboat arrives half a day late and the next Xboat coming down that same link arrives half a day early? Send two Xboats on down the line a few minutes apart? That seems logistically impractical, somehow...

On the grand scale, data moves down the line at the one-link-per-week-because-of-how-Jump-works rate (averaging 2.6 parsecs per week, we are told), and given that outbound ships are dispatched minutes after inbound ships arrive, I do not see daily departures making a significant contribution compared to the one-week-per-Jump constraint that dominates the overall throughput of the system.

 

[aramis]

Aramis:

I am seeing a scheduling issue, however.

If using the common 168 hours ± 10% formula for Jump duration, any given "scheduled" outbound Xboat will in practice have a 33.6-hour departure window. You can tentatively schedule them for daily departures, but what do you do operationally when one Xboat arrives half a day late and the next Xboat coming down that same link arrives half a day early? Send two Xboats on down the line a few minutes apart? That seems logistically impractical, somehow...

On the grand scale, data moves down the line at the one-link-per-week-because-of-how-Jump-works rate (averaging 2.6 parsecs per week, we are told), and given that outbound ships are dispatched minutes after inbound ships arrive, I do not see daily departures making a significant contribution compared to the one-week-per-Jump constraint that dominates the overall throughput of the system.

No. They always leave on time. they don't wait for the incoming. If it's early, great. If it's late, it goes on the next one. That's why it's a network, not a relay chain.

Which is why you have that spare... so the boat does 6-8 days in jump, jumps again on day 9...

 

[rancke]

To maintain a daily trip, on a given linkage (remembering that only about 10% of worlds are actually linked by X-boat - hans, check the canonical maps; no line, no X-boats)...

Wil, check logic and common sense. There are no rails in jumpspace. A link is simply an Xboat at one station being sent to another station within 4 parsecs. Interpreting the lines to be the only ones that Xboats are sent along gives us such absurdities as taking three jumps to get the news from Roup to Efate.

Of course, since the news get from Regina to Efate in one week by navy courier, one could argue that such massive inefficiency is nugatory, but it still seems very strange.

(Note that I'm not saying this isn't the interpretation the orginal writers meant, and for all I know is the interpretation that Marc Miller still favors. All I'm saying is that such an interpretation is absurd.)

A daily X-boat is thus about 19 XB's and 2-3 XT's.

Of which One or two are present in a system at any one time. I'm inclined to believe in a couple more spares.

Also, keep in mind that about 3% of jumps go awry. In MT, MGT, TNE, and T4, they're normally outside the target window in time, and often in space. So you need an extra XT in system to go fetch the lost ships. And you cannot tell the incoming XB's to switch target points...

Orr is assuming that the X-boat station is not in orbit around the mainworld but is stationary relative to the system.

Assuming worst case - MT -

These different rules can't all be true for the same universe. Who says the MT rules are the ones that are correct for the OTU?


Hans

 

[aramis]

Wil, check logic and common sense. There are no rails in jumpspace. A link is simply an Xboat at one station being sent to another station within 4 parsecs. Interpreting the lines to be the only ones that Xboats are sent along gives us such absurdities as taking three jumps to get the news from Roup to Efate.

Of course, since the news get from Regina to Efate in one week by navy courier, one could argue that such massive inefficiency is nugatory, but it still seems very strange.

(Note that I'm not saying this isn't the interpretation the orginal writers meant, and for all I know is the interpretation that Marc Miller still favors. All I'm saying is that such an interpretation is absurd.)


Of which One or two are present in a system at any one time. I'm inclined to believe in a couple more spares.


Orr is assuming that the X-boat station is not in orbit around the mainworld but is stationary relative to the system.


These different rules can't all be true for the same universe. Who says the MT rules are the ones that are correct for the OTU?


Hans

That's the edition I run, and know the odds best. TNE is actually more likely to have misjumps (because any failure on the 3 required rolls results in a misjump), and T5 I've not calculated the odds, but it's THE reference edition currently. MT's got the highest odds of minimal disruption misjumps.

T5 is dependant more upon skill, and still has the issue that distance becomes a term in the equation, setting the difficulty. If we list each edition by official setting, then Jumpspace is changing by 1900 to something much harder to navigate, but able to support much longer jumps.

 

[mike wightman]

No. They always leave on time. they don't wait for the incoming. If it's early, great. If it's late, it goes on the next one. That's why it's a network, not a relay chain.

Nope.

Read Traders and Gunboats, you will come across some interesting stuff:

it jumps, relays its messages to the station on arrival, and then waits to be
picked up by a tender, to be refuelled and sent on its way with a new load of
messages. The local station, meanwhile, accepts messages, encodes them, and
transmits them to a tender at the edges of the stellar system. Messages brought by
the arriving xboat and intended for further down the line are consolidated with the
new data and all are sent on to another xboat already fuelled and standing ready to
leave. The entire network operates like the pony express - messages are always
moving at top speed. Transfer time for messages from one xboat to another can be
as short as ten minutes, and is rarely more than an hour.

 

[kilemall]

Nope.

Read Traders and Gunboats, you will come across some interesting stuff:

Ya, that's what I remember about it.

Which begs the question, perhaps there should be a big transmitter and receiving dish/hull array to facilitate max speed transmissions? Could be a big chunk of that bridge.

 

[aramis]

Nope.

Read Traders and Gunboats, you will come across some interesting stuff:

T&G notes that it transfers to the one waiting to go. It doesn't say it immediately goes. Been down that rabbit hole in '96 on the TML. the only way the network works is if departures remain on schedule. If it's daily, then the next scheduled daily goes out with any data packets that make it in in time. Any that are late go on the next one out, which, logically, should be ready before the daily departure goes.

 

[McPerth]

Actually, a station would have 3 options:

Unless the incoming boat is scheduled for maintenance or signal need for repair, there is no need to get it into be serviced by a large tender or an orbital station

I disagree in this point, as even if the boat could jump again without XT servicing (fueling aside), the pilot would probably not.

We forget that inside the XB there's a person, that even if he/she must be quite solitary to endure the job, being a full week out of contact with any other person must be quite taxing, and will probably need some company for a while.

So, I guess the XB must be taken to the the XT, aside of minimal servicing for the boat, for the pilot to keep his/her sanity for any length, even if that means to change the pilot and leave the incoming one some rest.

A) The "pilot" of the Jumper calls the all clear and a resupply shuttle (more or less droned) shows up with50 t of fuel, the mail bag, the Life support supplies, whatever material for in jump maintenance... a Freight Handler, a J-drive expert to run extended diag on the iddle J-drive and the replacement crew

(bold is mine)

What do you mean with the mail bag?

I always have assumed that the XB carried mostly electronic mail, that skirt transmited to the next relay one (either directly or usen the XT as relay) for it to leave and before being taken by the XT in order to keep speed.

And IIRC the XB has not much cargo space for a mail bag. My guess is that phisical mail (be it paper letters, small packages, etc...) go by courrier or commercial shipping (the mai lcontracts), even through the XB network lines.

 

[McPerth]

A tender's hangar can hold two boats.

This may be version dependent, but in MT (As described in HT, page 81) the XT has hangar space for 510 dton of ships, meaning that it can hold up to 5 XB on it...

 

[rancke]

This may be version dependent, but in MT (As described in HT, page 81) the XT has hangar space for 510 dton of ships, meaning that it can hold up to 5 XB on it...

The deck plan in Of Xboats and Friends can carry four Xboats. With some waste space. And the figures given seem to be all over the place. The vehicle bay is said to be 40x28.5x12 meters, which by my calculation makes more than 1000T.

But the plans are nice.

(And as I said in a previous post, the original drawing seems to be of a 400T vessel or thereabouts.)


Hans

 

[McPerth]

I'm with Hans in the fact that any X-boat base should send XB to all such bases in range if information is to move with any speed, regardless they being united with a line in the map or not.

Let's imagine a message must go from Lanth (SM1719) to Lunion (SM2124).

By following the lines given in the map, and using only jups from one system to the next in the line, the message will travel Lanth (SM1719) => D'Ganzio (SM1920) => Ivendo (SM2319) => Icetina (SM2418) => Fosey (SM2621) => Resten (SM2323) => Lunion (SM2124), for a total of 6 jumps (6 week delay).

Alternatively, by using Hans logic, it could travel Lanth (SM1719) => D'Ganzio (SM1920) => Ivendo (SM2319) => Resten (SM2323) => Lunion (SM2124), for just 4 jumps, and 4 weeks delay, speeding it for about 33%.

Similar thing happens to send a message from Glisten (SM 2036) to Trin (SM3235), where folloing the lines is also 6 jumps but can be achieved with 4 is skipping them from X-boat base to X-boat base, and a paradigmatic one would be if you have to send a message from Chamois (SM3139) to its subsector capital in Trim (SM3235), that could be reached in a single jump with Hans logic but it needs 5 jumps by folloing the map lines....

 

[boomslang]

Ya, that's what I remember about it.

Which begs the question, perhaps there should be a big transmitter and receiving dish/hull array to facilitate max speed transmissions? Could be a big chunk of that bridge.

Actually, if you look at the exabytes or even zettabytes of data (14dtons of comp Model/4 auxiliary hardware and therefore TL10 storage) that are supposed to be transmitted across planetary (~10000km) distances in a few minutes' time, you are looking at something like a terawatt or even an exawatt gamma-ray laser to handle the bandwidth transmission.

Best to handwave it away and not think about it, I figure...

:CoW:

 

[McPerth]

The deck plan in Of Xboats and Friends can carry four Xboats. With some waste space. And the figures given seem to be all over the place. The vehicle bay is said to be 40x28.5x12 meters, which by my calculation makes more than 1000T.

But the plans are nice.

(And as I said in a previous post, the original drawing seems to be of a 400T vessel or thereabouts.)


Hans

In fact, in MT is told about 570 dtons of hangar. As the hangar needs are 150% of volume for vehicles (under 20 dtons), 130 for small crafts (20-100 dtons) and 110% for spacships/starships (100+ dtons), those 510 dtons are calculated for spaceships.

But also in MT the X-boat could have maneuver drive, as it needs only 25 dtons of jump fuel (due to the reduced needs in MT) and does not need the 20 dton bridge...

 

[boomslang]

T&G notes that it transfers to the one waiting to go. It doesn't say it immediately goes. Been down that rabbit hole in '96 on the TML. the only way the network works is if departures remain on schedule. If it's daily, then the next scheduled daily goes out with any data packets that make it in in time. Any that are late go on the next one out, which, logically, should be ready before the daily departure goes.

I never found that rabbit hole convincing. The historical Pony Express was able to work just fine with an "immediate departure" system.

And if you are going to be looking at a packet model, again, things like Signal Theory say that you get into diminishing returns once you try to move packets at more twice the transmission frequency, and even twice the frequency is a lot of work for a small return.

The Xboat network runs at a frequency of one Jump per week; pushing to two Xboats outbound on any link per week buys you perhaps +10% of your overall bandwidth in practice, any advantages of which you undercut by half or so when you take to loitering around waiting to leave on some sort of schedule.

The Xboat network is a classic "best effort" packet routing network, just like the Pony Express was. That how it is described, and there is little that can be done to improve it, because math.

 

[aramis]

I never found that rabbit hole convincing. The historical Pony Express was able to work just fine with an "immediate departure" system.

And if you are going to be looking at a packet model, again, things like Signal Theory say that you get into diminishing returns once you try to move packets at more twice the transmission frequency, and even twice the frequency is a lot of work for a small return.

The Xboat network runs at a frequency of one Jump per week; pushing to two Xboats outbound on any link per week buys you perhaps +10% of your overall bandwidth in practice, any advantages of which you undercut by half or so when you take to loitering around waiting to leave on some sort of schedule.

The Xboat network is a classic "best effort" packet routing network, just like the Pony Express was. That how it is described, and there is little that can be done to improve it, because math.

The historical pony express only ran for 19months, and only ran a single route (St Joseph MO to Sacramento CA), and was both expensive and very limited. Further, it only did the hot swap on (typically) 5-8 stations per day. TO send something, you took it to the nearest station where your stuff waited for the day's rider going the correct direction. The rider didn't hot swap at night - he stayed at the waystation, as did the mail, until morning, where additional local mail might be added. And only the mail and rider swapped; the horse generally went back and forth over the same 10-20 miles, unless sick or injured.

Since the canonical XBoat routes are regular service, and you cannot provide regular service without a schedule, and our "inspirational prototype" actually departed on a schedule every morning...

The only logical way to run the network is scheduled departures (since you cannot actually schedule the arrivals), and the canonical X-Mail is digital only. Canon also has the pilots swapping out, as well as the ships. And even with daily departures, it's still better for the network overall to depart on schedule, because few X-boat stops don't have multiple destinations served; what is there goes on schedule. What isn't waits for the next one going.

 

[Orr]

This may be version dependent, but in MT (As described in HT, page 81) the XT has hangar space for 510 dton of ships, meaning that it can hold up to 5 XB on it...

If you compare only volume to volume sure. Sadly, x-boats aren't liquid. We've got to deal with their shapes too.

That 510dTon has certain physical dimensions, a 100dTon x-boat has certain physical dimensions, and, given those physical dimensions, there will be a certain number of shapes which can fit inside another shape.

Admittedly, I only glanced at the T&G deckplan and maybe more than two boats can fit in that hangar but volume isn't the only concern.

I'm with Hans in the fact that any X-boat base should send XB to all such bases in range if information is to move with any speed, regardless they being united with a line in the map or not.

That's the Regency's xWeb system from TNE. It's a good system, but it's not the x-boat system. It has daily departures too.

The fact that the Regency's xWeb system is described as different from the Imperium's x-boat system is telling. The fact that we're explicitly told that the previous x-boat system was a control system rather than a communications system and that the xWeb system is communication system rather than a control system should be telling too.

The historical Pony Express was able to work just fine with an "immediate departure" system.

As Aramis explained, the Pony Express didn't exactly do that. There were "hot swaps" in which the rider jumped from one horse to another with his mochila, but most of the time the rider got a drink, grabbed a meal, visited the outhouse, etc. before galloping on to the next station.

And if you are going to be looking at a packet model, again, things like Signal Theory say that you get into diminishing returns once you try to move packets at more twice the transmission frequency, and even twice the frequency is a lot of work for a small return.

That's a very good point and it may be why x-boat departures are tied to a big percentage of a jump's temporal variation.

The Xboat network runs at a frequency of one Jump per week...

No, it's a jump a day. Individual boats jump once (or fewer times) a week, but a link is seeing one arrival and one departure every day.

The Xboat network is a classic "best effort" packet routing network, just like the Pony Express was. That how it is described, and there is little that can be done to improve it, because math.

That's a good way to explain it. You could have departures leaving every 12, 6, 4, or fewer hours but is the cost and effort worth the return? What good is shaving a few hours off the arrival of information a week or more old?

Anyway, getting back to my point...

... the frantic operational tempo presumed in several early posts in this thread does not exist. X-boats arrive/depart in a relatively small region, tenders can traverse that region quickly, a departing x-boat is one that has been previously prepped and staged instead of the one which had just arrived, T&G has message transfers between boats taking as much as an hour. There is plenty of time for the work to get done. There is no need for mass drivers slinging boats about, 6gee drones shuttling fuel, passenger, and parcels, or any of the other suggestions that were made. (It's not that those suggestions weren't good or weren't well thought out - they were good and well thought out - it's just that they aren't needed in the OTU's x-boat system.)

 

[Patron Zero]

The deck plan in Of Xboats and Friends can carry four Xboats. With some waste space. And the figures given seem to be all over the place. The vehicle bay is said to be 40x28.5x12 meters, which by my calculation makes more than 1000T.

But the plans are nice.

(And as I said in a previous post, the original drawing seems to be of a 400T vessel or thereabouts.)


Hans

The specifications from that article list that tender as having an 1100Ton displacement.

And agreed, the plans are very well presented, an additional profile view of the 'front-rear' wide face would have been a nice inclusion.

 

[Selandia]

...

What do you mean with the mail bag?

I always have assumed that the XB carried mostly electronic mail, that skirt transmited to the next relay one (either directly or usen the XT as relay) for it to leave and before being taken by the XT in order to keep speed.

And IIRC the XB has not much cargo space for a mail bag. My guess is that phisical mail (be it paper letters, small packages, etc...) go by courrier or commercial shipping (the mai lcontracts), even through the XB network lines.

you are right

The Mail Bag refers here to whatever "From Hand of Officer To Hand of Officer Only" Brown enveloppe/ attache case/ box ... or original documents the Scout service may wish to move for itself. You are right there is no canonical mention of commercial small package trade for Xboat. You may still think that a couple of cubic feet are available for internal use (I just thought that Purolator would not ship DHL its internal stuff). I did not intend to create a new business fot the Xboat.

have fun

Selandia

 

[aramis]

If you compare only volume to volume sure. Sadly, x-boats aren't liquid. We've got to deal with their shapes too.

That 510dTon has certain physical dimensions, a 100dTon x-boat has certain physical dimensions, and, given those physical dimensions, there will be a certain number of shapes which can fit inside another shape.

Admittedly, I only glanced at the T&G deckplan and maybe more than two boats can fit in that hangar but volume isn't the only concern.



That's the Regency's xWeb system from TNE. It's a good system, but it's not the x-boat system.

The fact that the Regency's xWeb system is described as different from the Imperium's x-boat system is telling. The fact that we're explicitly told that the previous x-boat system was a control system rather than a communications system and that the xWeb system is communication system rather than a control system should be telling too.

Given the dimensions of the bay and boats, you can actually fit 4 into the one in S7. No two of them will have the same orientation, tho... (I played around with the correct shapes/sizes in Sketchup.)