Gas Stations, or....

...How many parsecs does your Superdreadnought get before it runs out of hydrogen?

Don't know why this question popped into my mind, but given that most of the on-board power for all Honorverse ships are Gravity-pinched Fusion Reactors and that they use (IIRC) Hydrogen for their primary fuel (after all, if it's good enough for Stellar evolution, it's good enough for us).

I guess why I was thinking about this is adding up the LY's on Mikes Tenth Fleet. They have been from Manticore to Spindle to Montana to Tillerman to Meyers to Mesa, and I would think that their fuel bunkers would be getting a bit thin if they haven't "gassed up"). (I won't mention that some are probably in need of a visit to a dockyard in the near future for routine '1000 ly' maintenance--except that I did--if someone else wants to explore this idea, go for it).

Now, there have been bits and pieces of textev that indicates most systems have some sort of 'hydrogen mining' and the ability for fueling ships, but we've never seen (IIRC) how the RMN (or for that matter, the RHN) fulfills it's requirements.

Never been a hint (again, IIRC) of a 'tanker' auxilary, even for the longest deployments, which would tend to indicate that either this is not an issue or it is no more problem than us pulling up to a filling station (having an SD pull up to your planet and say 'fill'er up' would be an interesting experience....

However, going into the SL might make this slightly more important, as systems are not quite as SL systems are not likely to be so accomodating as before, perhaps to the extent of voiding their stocks into space prior to GA ships arrival. Depending on the range of the GA ships and how many systems refuse (or act) to fuel them, things could get a little pinched for Our Heroes.

Or perhaps it is a molehill and hydrogen supplies are so plentiful and abundant and SD's can travel halfway across the Galaxy on a single load of Hyrogen...but I doubt it is that simple.

It never is that simple. Anyone who has read/dealt with the military knows that in their bones.

Comments and data would be most welcome.

Some of it is going to depend on the route they took and the availability of grav waves.

While undersail in a grav wave you can pull power from the wave to power your ship. Now I doubt a military ship would be willing to put all it's reactors in cold shutdown mode, but you should still be able to save a lot of fuel by sticking to grav waves.


I have a vague recollection that Manticoran BCs have fuel and stores for months of operation (raiding), so that might be enough fuel to do an out-and-back raid at least 300+ lightyears into an enemy's rear - 40 days one-way in the Eta bands. (And presumably that's counting on relatively little grav wave time)
I'd be surprised if SDs were shorter legged than that...

Hutch wrote:...How many parsecs does your Superdreadnought get before it runs out of hydrogen?

Don't know why this question popped into my mind, but given that most of the on-board power for all Honorverse ships are Gravity-pinched Fusion Reactors and that they use (IIRC) Hydrogen for their primary fuel (after all, if it's good enough for Stellar evolution, it's good enough for us).

I guess why I was thinking about this is adding up the LY's on Mikes Tenth Fleet. They have been from Manticore to Spindle to Montana to Tillerman to Meyers to Mesa, and I would think that their fuel bunkers would be getting a bit thin if they haven't "gassed up"). (I won't mention that some are probably in need of a visit to a dockyard in the near future for routine '1000 ly' maintenance--except that I did--if someone else wants to explore this idea, go for it).

Now, there have been bits and pieces of textev that indicates most systems have some sort of 'hydrogen mining' and the ability for fueling ships, but we've never seen (IIRC) how the RMN (or for that matter, the RHN) fulfills it's requirements.

Never been a hint (again, IIRC) of a 'tanker' auxilary, even for the longest deployments, which would tend to indicate that either this is not an issue or it is no more problem than us pulling up to a filling station (having an SD pull up to your planet and say 'fill'er up' would be an interesting experience....

However, going into the SL might make this slightly more important, as systems are not quite as SL systems are not likely to be so accomodating as before, perhaps to the extent of voiding their stocks into space prior to GA ships arrival. Depending on the range of the GA ships and how many systems refuse (or act) to fuel them, things could get a little pinched for Our Heroes.

Or perhaps it is a molehill and hydrogen supplies are so plentiful and abundant and SD's can travel halfway across the Galaxy on a single load of Hyrogen...but I doubt it is that simple.

It never is that simple. Anyone who has read/dealt with the military knows that in their bones.

Comments and data would be most welcome.

Traveling between one system and another would be done primarily under Warshawski sail (free power, allowing shutdown of the ships' fusion reactors as long as the ships are in the wave) and impeller drive only between gravity waves and in normal space from the hyper limit to the destination.

While in orbit around a planet, unless a tactical reason exists, or is suspected to exist, where a rapid response requiring maneuvering using the impeller wedge is necessary (such as faced by Zavala at Saltash), ships would shut down their impeller wedges and all but one fusion reactor (for maintenance, and conservation of reactor mass).

IIRC, Meyers is mentioned as having a gas mining industry, and Mike would have topped off 10th Fleet's fuel bunkers there.

Vince and Johnathan, good points, but one thing to clarify:

Vince wrote: Traveling between one system and another would be done primarily under Warshawski sail (free power, allowing shutdown of the ships' fusion reactors as long as the ships are in the wave) and impeller drive only between gravity waves and in normal space from the hyper limit to the destination.

Like Jonathan S. mentions, that only applies in a grav wave; if you're in normal hyperspace, you're burning hydrogen.

I guess it depends on how much H an SD can carry (and under what pressure) and how much its' Fusion reactors require to perform their operations.

And unless we have any nuclear physicists with us on the Forum (which is not impossible, I suppose), we'll probably never know.

But it is fun to speculate.

Hutch wrote:...How many parsecs does your Superdreadnought get before it runs out of hydrogen?

Don't know why this question popped into my mind, but given that most of the on-board power for all Honorverse ships are Gravity-pinched Fusion Reactors and that they use (IIRC) Hydrogen for their primary fuel (after all, if it's good enough for Stellar evolution, it's good enough for us).

I guess why I was thinking about this is adding up the LY's on Mikes Tenth Fleet. They have been from Manticore to Spindle to Montana to Tillerman to Meyers to Mesa, and I would think that their fuel bunkers would be getting a bit thin if they haven't "gassed up"). (I won't mention that some are probably in need of a visit to a dockyard in the near future for routine '1000 ly' maintenance--except that I did--if someone else wants to explore this idea, go for it).

Now, there have been bits and pieces of textev that indicates most systems have some sort of 'hydrogen mining' and the ability for fueling ships, but we've never seen (IIRC) how the RMN (or for that matter, the RHN) fulfills it's requirements.

Never been a hint (again, IIRC) of a 'tanker' auxilary, even for the longest deployments, which would tend to indicate that either this is not an issue or it is no more problem than us pulling up to a filling station (having an SD pull up to your planet and say 'fill'er up' would be an interesting experience....

However, going into the SL might make this slightly more important, as systems are not quite as SL systems are not likely to be so accomodating as before, perhaps to the extent of voiding their stocks into space prior to GA ships arrival. Depending on the range of the GA ships and how many systems refuse (or act) to fuel them, things could get a little pinched for Our Heroes.

Or perhaps it is a molehill and hydrogen supplies are so plentiful and abundant and SD's can travel halfway across the Galaxy on a single load of Hyrogen...but I doubt it is that simple.

It never is that simple. Anyone who has read/dealt with the military knows that in their bones.

Comments and data would be most welcome.

For the Fleet train, there probably is a fuel ship along with the repair/ammo ships. Most systems will maintain some sort of hydrogen farm for refueling visitors; capacity is questionable.

But there is textev to support shutting down most power systems until just before you come out of a grav wave; unless you are actually fighting, you don't have the energy weapons hot, sidewalls, EW--the load is thus also reduced in hyper, under sail anyway.

The Hali Sowle had enough fuel and provisions that Zilwicke was complacent about spending as much as a year drifting. And if you have power and grab some ice, you can get the hydrogen yourself. Maybe.

Rob

It all depends on the needs of the plot.

kzt wrote:It all depends on the needs of the plot.

To borrow from Lyonheart:

Always with the negative waves Moriarty, ALWAYS with the negative waves!

--Sgt. Oddbal, "Kelly's Heroes"

I'm thinking that what RFC did is make the availability of "fusion fuel" ubiquitous, certainly that's what I would do as an author.
Given that "we" the reader in "post X thousand years diaspora" have had starships for x-hundred years now, and all ships are fusion driven... Which would mean that any system capable of supporting even freighters would have the equivalent of a refill your bunkers" bunkerage sales point. Which works just as well as a fleet train of ships. I think the USN does that in some areas, the DD commander actually has a sort of "fill my ship up" credit card for fuel, fresh food, etc. at the local great big allied harbor.

If that were the actual mechanism for fueling the ships wouldn't need to be stated except for a specific mission profile, aka "for this special mission, we need to XYZ" which is not standard-fleet practice, etc. Similarly, totally abandoning a system such as Grendelsbane would include nuking the fueling point. Thoughts?

Hutch wrote:

kzt wrote:It all depends on the needs of the plot.

To borrow from Lyonheart:

Always with the negative waves Moriarty, ALWAYS with the negative waves!

--Sgt. Oddbal, "Kelly's Heroes"

Poor baby, he took the fiction out of science fiction and added a little science to the mix with his snarky comment. (Numbers accelerations, velocities, for 100% hydrogen ships have been bandied about on this forum for years) Boo Hoo.

Power of plot reigns supreme. Distance traveled between fuel ups is completely handwavium.

Otherwise, even with the pearl saying "up to" 60% of energy is from across the hyperwall to power the ships' impeller drive, the ship would still have to be 100% hydrogen to get anywhere in the time/velocity, let alone hundreds of light years distance. Reality would require 95% of the ships energy budget come from the impeller drive if not more just to reach Grayson from Manticore.

Why stop at 300LY RoO? May as well state 1000's. You will note RFC has never even hinted at distance limitations other than in terms so abstract as to be wholly meaningless.

--snip--

wastedfly wrote:...Power of plot reigns supreme. Distance traveled between fuel ups is completely handwavium....

--end snip--
I disagree, though the actual numbers, yeah, that's whatever RFC says it is. One of the reasons we play here is that at least David is consistent book to book with the tech.

The only times range is really mentioned is relative to a freighter (all freighters nee needs uber-big, extended range fuel supplies, same way a supertanker or super-whatever-they-call the marine transports do on the wet-seas. Slow as snot compared to mil-spec ships, but they get there), and the wormhole exploration ship that got blown up by the Mannerheim SDF.

That ship has specially purposed to have very low crewing requirements in return for the ability to get back to someplace known just in case the wormhole goes off into "weirdspace" (uninhabited) and can't just transit back through the wormhole to get home. Seems like the range was stated somewhere at around 800LY?

Personally, I like the way it's done, otherwise there's no ship range limitation, presumably any impeller/hyper capable vessel could just have a ship extend a "super-hydgrogen fuel harvester sail" and go by Jupiter or wherever, and handwavium, lah-de-dah! back to full power.