Without the proper system (UNREP) you just can’t refill a ship in space, and even supply’s are hard to transfer. additionally there is maintenance to be considered. No the problem is still the fact that the design of a Xboat has not been updated and the concept of having a huge fleet of these expensive tenders to support the xboat network is facially stupid. Adding a maneuver 1 drive and placing a station about the ‘north/south pole’ of the Star to service and resupply the xboats is far cheaper that have a minimum of two or many more tender in 90% of the system and anywhere from 12 to 24 tenders in 10% of systems. Tenders make sense for temporary use when needed but not as your primary support system.
Why X-Boat tenders
- Thread starter tytalan
- Start date
Tenders make sense for their stated role. Nothing in their original description or published since says that XBoats *don't* mostly jump to deep space stations to be ferried in by small craft. But for rescue, recovery, temporary or casual coverage and ferrying boats around the network to and from the Depots where you would expect them to be overhauled and maybe built, you have the tenders.
(Which are able to ferry, refuel and supply Type-S ships if needed as well.)
But I'd also dispute that static stations are a much cheaper solution either. Those need to be maintained too. A tender on station can return to base for refit and repair without needing resources to be ferried to it from the Depot, with its replacement arriving under its own power.
"Placing a station about the north/south pole of the star"... yeah, orbits don't work like that. You can place something in a polar orbit, but that will still move the same speed as one in an equatorial orbit, or any angle between those. Space stations are not fixed locations; you may as well place them in orbit at 100D of the mainworld.
There's also no reason a Tender can't carry small craft to assist with the tending. It's got a 400ton ship bay, after all. It's a flexible solution.
(Which are able to ferry, refuel and supply Type-S ships if needed as well.)
But I'd also dispute that static stations are a much cheaper solution either. Those need to be maintained too. A tender on station can return to base for refit and repair without needing resources to be ferried to it from the Depot, with its replacement arriving under its own power.
"Placing a station about the north/south pole of the star"... yeah, orbits don't work like that. You can place something in a polar orbit, but that will still move the same speed as one in an equatorial orbit, or any angle between those. Space stations are not fixed locations; you may as well place them in orbit at 100D of the mainworld.
There's also no reason a Tender can't carry small craft to assist with the tending. It's got a 400ton ship bay, after all. It's a flexible solution.
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Condottiere
Emperor Mongoose
Could also depend on what else they might be doing.
Or, servicing.
Or, servicing.
Sigtrygg
Emperor Mongoose
"High population and high technology star systems can be expected to have up to twelve xboats presentat one time, probably distributed evenly between arriving and departing ships. Lower population systems will have fewer xboats. The presence of a scout base will increase the probability of xboats being present. Imperial Way Stations, maintained by the scouts to service and overhaul all scout vessels, will have many xboats present, although most will be in some state of disrepair."
Each boat requires 40t of fuel, a replacement pilot, life support, spares. So you need at least six small craft that can carry 40t fuel etc as a bare minimum. These smallcraft must then go back to a base to refuel for the next xboat they need to service - how often are the xboats arriving ans what is the flight time of the smallcraft to and from its base?
Why not just put a maneuver drive on the base so you can move it to the xboats?
The assumption is that the xboats arrive at a known location rather than scattered all over the system.
Each boat requires 40t of fuel, a replacement pilot, life support, spares. So you need at least six small craft that can carry 40t fuel etc as a bare minimum. These smallcraft must then go back to a base to refuel for the next xboat they need to service - how often are the xboats arriving ans what is the flight time of the smallcraft to and from its base?
Why not just put a maneuver drive on the base so you can move it to the xboats?
The assumption is that the xboats arrive at a known location rather than scattered all over the system.
Condottiere
Emperor Mongoose
It does tend to operate on a regular schedule.
Assuming a towing speed of factor one, since we'll assume there are no inertial compensators onboard, you could send a five tonne skiff to haul back an arrived express boat.
Assuming a towing speed of factor one, since we'll assume there are no inertial compensators onboard, you could send a five tonne skiff to haul back an arrived express boat.
Fluffy Bunny Feet
Banded Mongoose
If you are transferring fuel UNREP is assumed and that is supposed to be quick and foolproof, even a minimal unit would take just over 2 hours for refuel/resupply of an X-Boat. Supplies for 1 person should be minimal and UNREP is supposed to handle that as well. Maintenance after a single weeks flight should be minimal and likely not needed for at least 4 weeks (or 16 parsecs of travel) at which point you swap X-Boats. Which I did mention. Worst case you have to tow it in while it transfers data to a replacement and as soon as they meet essential packages or passenger can be transferred if no packages/passengers then the replacement can jump as soon as the data is verified.
Fluffy Bunny Feet
Banded Mongoose
You can with a POWERED orbit where the M-Drive is constantly running to keep you in that position. Robert L. Forward patented using a solar sail to "hang" satellites over the North and South pole of Earth and there is no reason that with a M-Drive you couldn't do the same over the Solar poles.
The whole concept of the Express network needs revision.
For my universe it is divided in 4 tiers.
Tier 1 is run by the central government and runs radially outward to all the Sector Capitals.
Tier 2 is run by the Sector governments and runs from the Sector Capitals to the Sub Sector Capitals. They are allowed to make runs laterally between otherwise unconnected Sector Capitals but not required.
Tier 3 is run by the Sub Sector government and runs from the Sub Sector Capital to the "Important Worlds" of the Sub Sector. They are allowed to make runs laterally between otherwise unconnected Sub Sector Capitals even in other sectors but not required. J-2 or J-3 couriers are often used for this.
Tier 4 is more ad hoc and worlds that want connections direct to the Sub Sector Capital but not deemed important enough can run their own connection. They can also connect to important trading partners locally or even across Sector/Sub Sector borders and this may result in tapping into the Tier 3 network either of their own sector or a neighbouring one even in another Sector. PCs may be involved in running or even creating such a link.
The higher the Tier the fancier the ships ranging for Tier 1 from J-3 X-Boats on the frontier to larger J6 X-boats using (reusable) drop tanks to make back to back jumps to speed things up in the high tech core, to Tier 4 using J1 freighters to deliver whenever they are going the right way. Most subsidized merchants on the frontier would be carrying mail routinely.
A different vision from the centrally run system of 3I
The maintenance cost for a ship is always much greater than a station it’s built right into the design. Maintenance is based on cost of the vessel/station which a station with maneuver of 0, no jump drive, and a smaller power plant needed without supporting these is going to be vastly lower. Add to that the size difference a tender is 1000dt while a station that does the exact same thing is only 800dt which is another great size reduction. In addition to this a station actually get cheaper the larger it is, a single station that does the job of two tenders is only 1500dt vs two tenders which are 2000dt. It’s simple math a station is by definition cheaper.
what this talk about Orbits they have no barring in the placement maneuver of 0 allows a station to maintain its position no matter where, orbits only matter if you have no maneuver at all so your statement doesn’t really work.
The simple fact is it’s cheaper to build xboats with maneuver 1 and stations to support them with tenders only used for temporary support.
A UNREP system requires tonnage not much mind you but you also need a maneuver drive for the small craft (minimum of M-3) and cargo plus all the other needed systems. Now for each tender replacement you need 3 to 6 of these small crafts which ends up again costing more than giving the xboat maneuver drive and using a station.
Here a station with everything the Tender has and the extra fuel and proper crew requirements and its price is half the tenders its maintenance is also half. I even added a modular cutter with the fuel skimming module to it. The cost savings makes the extra cost for the xboat with maneuver drive nothing. One note I built both at TL 15 because these are imperium craft and that only makes sense as well as it lower the costs but not by any margin that would change the numbers substantially.
Attachments
In that concept, the satellite is still in Solar orbit. The sail is just offsetting the Earth's gravitational vector. That's also the case with one placed in a Lagrange point - those are just where the satellite's orbits of the primary and the secondary bodies are in synch. I'm fairly sure a solar sail solution wouldn't work to hold position above a star, but a magic reactionless drive one might. That's imaginary physics, so let's say okay.
What advantage would that scenario, with a station constantly running the M-Drive it is now required to have, have over a station placed in normal solar orbit outside the jump shadow? If angle to and from another system is an issue, just use an orbit that's never, or rarely obscured by the jump shadow. Or... maybe you should use a mobile base that can change it's position every few months to optimise things?
In practice, unless the mainworld is inside the star's jump shadow, I'd have thought in most cases it would be most efficient to put a station in orbit outside the planet's jump shadow, where the local defenses can easily cover it and the station or tender is closer to the shipyard, starport and non-XBoats that are doing scout and courier work that involves the mainworld.
Condottiere
Emperor Mongoose
Factor/zero acceleration, in theory.
For the first part the rules literally state that a station with maneuver 0 constantly maintains its position. Also that’s not how orbital mechanics work if a station is in a stable orbit like Lagrange points it does not need anything to maintain its orbit that why those points are so beneficial, same with satellites orbiting the earth if it is in a stable orbit you don’t need to counter the effects of gravity because they are balanced by the centrifugal force trying to throw the satellite out of orbit. Most satellites don’t even have any sort of drive reaction or other.
As for advantages there are multiple
1) outside of normal traffic zones, Xboat traffic can be very heavy especially in hub systems with as many as 6 or more xboats jumping in out in any hour, that’s a lot of extra traffic especially since these very systems are also more likely to be commerce hub.
2). helping to prevent accidents and accidental piracy (no pirate in his right mind would attack a xboat or tender on purpose that’s the fast track to meeting a battle cruiser)
3). Clear transmission to the entire system this makes sense especially in systems with dispersed population.
4). There are many system that don’t have a consolidated main world such as systems where the main world is a asteroid belt
A station orbiting a world outside 100D isn't exactly cluttering local space, no matter how much traffic is arriving and departing from it. All the commercial stuff is happening inside that bubble.
Unless you're running some custom thing, even asteroid belts have one designated starport. If it's important enough to be on the X-Boat network, that's where the information hub it. Sticking the scout station half a system away from that makes little sense. If there's a need to relay communications to a secondary settlement, that can be done by the locals - the scout base is primarily catering to incoming and outgoing XBoats and turning over their data. Placing it in a station keeping position far from everything of interest in the system just seems like a strange idea.
But yes. In a particular system it may make sense to have a station in solar orbit. The common situation would be where the mainworld is inside the star's jump shadow, The base or tender needs to be located outside that.
Maybe the base is sited around an outer planet, or a gas giant for easy fuel gathering. Maybe there's a planet or moon of much more interest to the Scout service than the mainworld. Maybe there's an outer system Naval base and it makes more sense to co-locate facilities.
There are Scout Waystations. There are Scout Bases. I am more than happy for there to be Scout XBoat Stations in many systems. But there are also plenty of good reasons and roles for XBoat Tenders.
Even if you put M-Drives in the X-Boats, which everyone is fully entitled to do in their TU, the data transfer is meant to happen ASAP, well before the boat itself gets to the Tender, so an XBoat thrusting at 0.5G or 1G, or a tug bringing it in, or a station tractoring it will not affect that.
(And that's another point, and a reason to leave out a full 1G drive. Rating 0 thrusters will bring the boat in soon enough.)
Unless you're running some custom thing, even asteroid belts have one designated starport. If it's important enough to be on the X-Boat network, that's where the information hub it. Sticking the scout station half a system away from that makes little sense. If there's a need to relay communications to a secondary settlement, that can be done by the locals - the scout base is primarily catering to incoming and outgoing XBoats and turning over their data. Placing it in a station keeping position far from everything of interest in the system just seems like a strange idea.
But yes. In a particular system it may make sense to have a station in solar orbit. The common situation would be where the mainworld is inside the star's jump shadow, The base or tender needs to be located outside that.
Maybe the base is sited around an outer planet, or a gas giant for easy fuel gathering. Maybe there's a planet or moon of much more interest to the Scout service than the mainworld. Maybe there's an outer system Naval base and it makes more sense to co-locate facilities.
There are Scout Waystations. There are Scout Bases. I am more than happy for there to be Scout XBoat Stations in many systems. But there are also plenty of good reasons and roles for XBoat Tenders.
Even if you put M-Drives in the X-Boats, which everyone is fully entitled to do in their TU, the data transfer is meant to happen ASAP, well before the boat itself gets to the Tender, so an XBoat thrusting at 0.5G or 1G, or a tug bringing it in, or a station tractoring it will not affect that.
(And that's another point, and a reason to leave out a full 1G drive. Rating 0 thrusters will bring the boat in soon enough.)
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Actually according to HG a maneuver of 0 is only capable of station keeping “
A maneuver or reaction drive with Thrust 0 allows for an orbiting space station to maintain position but is not sufficient to move the hull any great distance.” not moving and there is no half ratings for a maneuver drive. What are you using for a hull dt percentage for your maneuver of .5? .75% of the ships tonnage.
As far as data transfer that’s done at the speed of light and the Tender rebroadcast the information (there a system that both have called “Mail Distribution Array”).
Here the thing you already do this by using a tender instead of a station. Another reason for having a tender station away from the actual star port is information control remember the xboat network is not the mail (actually mail is carried as freight on merchant ships) it’s command and control. Yes the xboats do carry important mail and news but that’s just to offset the costs its primary purpose is as the imperiums government’s information and command system.
Sigtrygg
Emperor Mongoose
Satelites require station keeping drives to maintain their orbits, even when at an L point. The JWST has station keeping engines to maintain its orbit.
James Webb Space Telescope - Wikipedia
"For spacecraft in a halo orbit around a Lagrange point, station-keeping is even more fundamental, as such an orbit is unstable; without an active control with thruster burns, the smallest deviation in position or velocity would result in the spacecraft leaving orbit completely"
taken from wikipedia article
Orbital station-keeping - Wikipedia
Condottiere
Emperor Mongoose
You have to define the actual thrust from acceleration factor/zero.
Remember, it's sufficient for a planetary soft landing.
Remember, it's sufficient for a planetary soft landing.
And where do you see that because HG 2022 doesn’t not say that at all.
Condottiere
Emperor Mongoose
The bridge has two weeks of life support and battery power, while emergency thrusters give it basic manoeuvring capabilities, equivalent to Thrust 0. A detachable bridge is even capable of soft-landing on a planetary surface.
My bad regarding the value of Thrust 0 M-Drives. I think I got confused because those are 0.5% of the hull and the other drives are all Thrust x 1% of the hull.
It's undefined, aside from "not sufficient to move the hull any great distance". Although... any constant thrust good enough to correct orbital decay is in fact quite sufficient to move the hull (It's not like you stop using the thrusters and then stop!). But it takes a long time to get anywhere. As with the Solar Sail, which is also Thrust 0 (P48).
I was sure there was a rule (possibly in an earlier edition?) that a ship with its M-Drive destroyed was still capable of limited maneuver, at thrust 0 on its attitude thrusters.
And yes. data is transmitted at the speed of light, but is also subject to the inverse square law, so signal gets four times weaker for each doubling of distance. And that affects bandwidth.
In addition, such a station at Sol would be about 8 light minutes away from the sun, with Earth eight light minutes away at a right angle; the straight line distance between earth and station being about 11 light minutes. 22 minute round trip to correct packet loss. It is NOT what you want to do if you can possibly avoid it.
It's undefined, aside from "not sufficient to move the hull any great distance". Although... any constant thrust good enough to correct orbital decay is in fact quite sufficient to move the hull (It's not like you stop using the thrusters and then stop!). But it takes a long time to get anywhere. As with the Solar Sail, which is also Thrust 0 (P48).
I was sure there was a rule (possibly in an earlier edition?) that a ship with its M-Drive destroyed was still capable of limited maneuver, at thrust 0 on its attitude thrusters.
And yes. data is transmitted at the speed of light, but is also subject to the inverse square law, so signal gets four times weaker for each doubling of distance. And that affects bandwidth.
In addition, such a station at Sol would be about 8 light minutes away from the sun, with Earth eight light minutes away at a right angle; the straight line distance between earth and station being about 11 light minutes. 22 minute round trip to correct packet loss. It is NOT what you want to do if you can possibly avoid it.
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