OTU Only: A Funny Thing Happened on the Way from Collace

[AnotherDilbert]

Second, for combat (or other very short duration use) it's cheaper at most TLs to carry additional power as capacitors than as power plant+fuel.

Why hasn't this been used in canon?

Because it is specifically banned. You must have a PP (with fuel) to cover all consumption.

Perhaps we could use extra capacitors to increase agility, which is very handy for Riders as they have a Tender with a large PP nearby. Unfortunately that is banned by the LBB5 errata.

 

[Grav_Moped]

Because it is specifically banned. You must have a PP (with fuel) to cover all consumption.

Perhaps we could use extra capacitors to increase agility, which is very handy for Riders as they have a Tender with a large PP nearby. Unfortunately that is banned by the LBB5 errata.

Never saw that, but it's probably next to the bit that precludes building a missile/sandcaster ship that always declares emergency agility to get its computer power for free.

 

[AnotherDilbert]

Never saw that, but it's probably next to the bit that precludes building a missile/sandcaster ship that always declares emergency agility to get its computer power for free.

Sandcasters and computers are still usable during Emergency Agility, but no weapons or, even worse, screens allowed.

Perfectly usable to break off from the reserve, but hardly in the battle line.

 

[Spinward Flow]

6Boat:
It’s possible at TL 12 to build a 400Td J6 Xboat using the "Xboat fuel loophole" (Jump fuel requirement, plus only 1 week power plant fuel at Pn 6 for the time in Jump). It's pretty darn cozy in there: the 6-man crew is in double-occupancy and there’s only 3Td left over for either cargo, message databanks, or a token maneuver drive (Size A for 0.5G) and 2Td fuel (24 Hrs at Pn 6). The design is entirely LBB2 ‘81 compliant aside from the power plant fuel allocation, but that’s a “cheat” that is more than supported in canon.

Counter-proposal.

LBB2.77 ... 100 ton TL=9 J6 Courier

• 100 ton custom hull, atmospheric streamlining = MCr11
• Jump-C (6), Maneuver-A (2), Power Plant-A (2) = 20+1+4 = 25 tons, MCr42
• Fuel Purification Plant: 200 ton capacity = 9 tons, MCr0.038
  • Refines 1 ton of unrefined gas fuel per 1 minute (20+60=80 minutes total with L-Hyd drop tank installed)
  • Refines 1 ton of water fuel per 10 minutes (200+600=800 minutes/13h20m total with L-Hyd drop tank installed)
• 20 tons of internal fuel (power plant only, 28 days endurance, 56 days powered down)
  • 60 ton external L-Hyd drop tank (Cr70,000 new/empty, Cr6000 reuse/empty)
    Drive performance reduced to Jump-3, Maneuver-1, Power Plant-1 while drop tank is retained.
• Dual Turret: Sandcaster, Missile = 1 ton, MCr1.6
• Bridge = 20 tons, MCr0.5
• Computer model/3 = 3 tons, MCr9
• Staterooms: 2 = 8 tons, MCr1
  • Crew (2): Pilot, Gunner
• Workshop: Life Support (4 tons, MCr0.5, removes need for life support overhead costs every 2 weeks)
• Cargo: 10 tons (5 tons mail vault, 5 tons other cargo)

Total tonnage = 25+20+20+3+8+4+20 = 100 tons (wasted space: 0 tons)
Total cost (first in class) = MCr65.708 (including new L-Hyd drop tank construction cost), 40 weeks construction time (LBB A5, p33)
10% discount volume production cost = MCr59.1372, 36 weeks construction time

Standard operating procedure is for the ship to rendezvous with a Drop Tank "catcher" craft so as to rent a 60 ton drop tank after breakout from jump into a star system. Once the drop tank is installed, the ship proceeds to wilderness refuel via skimming (both Boughene and Regina are moons orbiting gas giants) before setting course for the highport in orbit around the mainworld. By wilderness refueling first, plenty of time is given for the fuel purification plant to refine the contents of the internal fuel tanks and exchange that refined fuel with the contents of the L-Hyd drop tank until all fuel aboard has been refined.

At the highport the contents of the mail vault and cargo bay are unloaded and turned over to starport authorities and revenue is collected. 16 hour standard post-jump preventative drive maintenance checks are conducted while docked at the highport while awaiting delivery of any mail or cargo that has already been delivered to the starport and is waiting on standby for transport to the the next destination. After routine drive maintenance is complete the ship is ready to depart at any time.

Once clearance for departure has been granted and the contents of the mail vault and cargo hold have been secured, the ship undocks from the highport and sets course for a jump point convenient for a drop tank "catcher" craft to pick up the L-Hyd drop tank after jump. The ship jumps using all the fuel in the drop tank (LBB2.77 drives have no jump governor), jettisons the drop tank and jumps.

Reference:
Canary Run: This project was established after the Fourth Frontier War by Dame Irshinri's father Zebulon, the previous Knight of Boughene. It's a J-6 messenger link to Regina at a 3-day cadence. This provides faster communication to the subsector capital than the 3-jump XBoat route or a 2-jump (J4+J3) alternative through Roup even when the latter run on daily intervals. The original ships were Israfil-class couriers (J6/1G, 400Td, TL-13, short-fueled*), five of which were built at Efate for this purpose with two serving as maintenance spares. (Why two spares? General Products knew they'd probably both be necessary at some point.) They have since been replaced by much smaller J-6 couriers sourced from Rhylanor by Duke Norris, who saw the value in this service.

Some high-importance message traffic from the County capital at Menorb is routed through the Canary Run, particularly when the transmission from Menorb aligns with the Canary's scheduled departure from Boughene.

It's called the Canary Run because the arrival of each courier is, in itself, the most important message it carries. In normal operation, one ship arrives every three days. In the event of a crisis (say, the Fifth Frontier War kicks off), the standby ship at Boughene carries the warning immediately; in the worst case the courier is prevented from departing at all -- and that's the message. Like a canary in a coal mine (or more precisely a warrant canary [Wikipedia]), the absence of a live canary is a warning of a danger that cannot be seen. Battle fleets are generally incapable of Jump-6, and would need at least 2 weeks to reach Regina from Boughene. So, at worst, Regina would have a few days, and possibly a week, to prepare for what's coming at them.

So for the Canary Run, the above 100 ton TL=9 J6 Courier would have recurring overhead expenses per jump of:

• L-Hyd drop tank rental: Cr6000
• Berthing Fees: Cr100
• Crew Salaries: Cr7000 per 28 days / Cr3000 per 12 days

Total cost per jump = Cr9100 per 10 days

Revenue generation per jump:

• 5 tons mail: Cr25,000
• 5 tons cargo transport: Cr5000

Revenue earned per jump: Cr25,000 (no cargo) to Cr30,000 (5 tons cargo)

In other words, even under subsidy the J6 Courier would be capable of turning a Cr3400-5900 profit every jump for the ship itself (after 50% revenue rake from the subsidy), with an expected turnaround time of 12 days/288 hours between jumps (including maneuvering, drop tank pickup, maneuvering, fuel skimming, maneuvering, docking, unloading, maintenance, loading, undocking, maneuvering, jump). 29*12=348 days per year per ship, so with 29 jumps per year profits on operation can run to Cr98,600-171,100 under subsidy per year (or MCr3.944-6.844 over 40 years, which is well short of 15% the purchase price of the ship in volume production).

If the ship is paid off in full and not subsidized, the profit per jump increases to Cr15,900-20,900 contingent upon transporting up to 5 tons of additional cargo beyond the contents of the mail vault. Again, with 29 jumps per year profits on operations can run to MCr0.4611-0.6061 per year (or MCr18.444-24.244 over 40 years, which is still short of 50% the purchase price of the ship in volume production)

A 3 day departure cadence of jumps would thus require 4x J6 Courier ships circulating each way in a two star system round trip scenario, with a preference for having 2 extra spares that can be rotated out of circulation for maintenance ... so a total of 10 ships would be desired for a 2 star sytem circuit (more ships would be needed for a 3 star system triangle rotation, such as Boughene/Regina/Lysen for example). L-Hyd drop tank services for 60 ton fuel tanks would be required at all destinations to be visited, which fortunately ought to easily be the case at both Boughene and Regina (and Lysen too if the Canary Run were expanded to cover Lysen/Jewell as well in a J6 triangle arrangement).

So although operationally the J6 Courier ships would be unable to earn back their construction costs over 40 years purely in terms of transport capacity, the VALUE of what they carry would in fact be far far higher in terms of advance warning of actions along the frontier. So while the transport revenues the ships generate might not be all that valuable, the information they carry could very well be considered invaluable/priceless as far as the contents of their communications can be concerned ... especially since the mail vault delivery method would not be subject to broadcast intercept and decryption methods, since it would involve a physical handoff of data drums and other "electronic paper" data transfers on physical media. So privacy of privileged communications would be assured in a different way from how the Express Network operates with completely different security protocols.

 

[Grav_Moped]

You'll run into a problem I hit when I tried to work out Jump Torpedoes: If you allow LBB5 for the drop tanks, you're also bound by its rules requiring Pn>=Jn and Computer Mod/#>=Jn. (I was trying to figure out how far a jump drive could jump itself and some fuel, scaling down the drive using the formulas underlying the LBB2 drive table*. Ended up needing drop tanks for higher JNs, then realized the Catch-22.)

But yes, drop tanks + LBB2 do allow some really overpowered low-interstellar-TL ships!

And the '77 version of LBB2 takes all the challenge out of it!


-------------
*If (as seems possible in LBB2 '77) you offload the course computation and drive control inputs to the launching ship, and don't need a power plant, a J-Torp is just a jump drive, fuel tank, jump cartridge player, cassette recorder, and a radio transmitter. Jump drive size is 5Td + (some percent I don't recall off hand) per Jn. Add the fuel percentage based on desired range, and solve for tonnage. Site search isn't turning up my posts on the subject (it's not in my "the littlest starship" thread).

For the record, I don't want J-torps in my game universe, but trying to figure out how they might have worked under LBB2 '77 was an interesting exercise.

EDIT: Added footnote.

 

[Spinward Flow]

If you allow LBB5 for the drop tanks, you're also bound by its rules requiring Pn>=Jn and Computer Mod/#>=Jn.

Negative.

LBB2.77 drives do not require Power Plant equal or above the Jump number.
Likewise, LBB2,77 drives do not require Computer model equal to or above the Jump number.
As someone pointed out to me previously (in a different thread) ... with unmodified LBB2.77 standard drives you only need enough computer CPU to run the Jump-6 program plus another program (or few) which can rotate through storage.

In the specific application of the Canary Run between Boughene and Regina you're doing ONLY Jump-6, so other jump programs are not needed (the ships are that specialized). If you expand the circuit out to include Boughene to Regina to Lysen and then back to Boughene, you still use Jump-6 exclusively since the use case for the ship(s) is a defined one that would use no other jump numbers (there's no tramp merchant stuff to see here). Under such conditions, the lack of a Jump Governor to require less than 60 tons of fuel for a 100 ton starship to jump fewer than 6 parsecs is superfluous, because the only jumps the ships of the class will be making are Jump-6.

So it's not like you need all the other jump programs to be able to jump a wide variety of distances.
6 parsecs is ALL YOU NEED (exclusively) for the Canary Run.

Oh and side note, Boughene, Regina and Lysen all have scout bases, so using the Canary Run a "faster XBoat" for exceptionally high value/privileged communications makes a lot of sense in this particular region ... enough so that I can easily imagine the IISS wanting to chip in a few credits to support the operation, even if it does operate at a loss of nearly MCr1 per year after accounting for construction costs over the lifetime of the starship class (so for 10 ships in circulation, that's about MCr10 per year net loss over 40 years).

Note that if you add Lysen into the mix, you only need to add 5 more ships, not another 10, to keep the dispatch tempo at 1 ship every 3 days if they all circulate in the same direction (in this case, clockwise ... Boughene, Regina, Lysen, Boughene ... as proposed above) in a triangle circulation. Default assumption is that if the Jewell subsector is attacked/invaded, once word is sent to Lysen then one of these J6 Couriers would be immediately dispatched directly from Lysen to Regina, rather than proceeding on to Boughene as normal.

And you had better believe that if a Canary Run ship needs to alter course to alert Regina about hostilities along the border, there's going to be a pre-arranged code for "We Need Priority SDB Escort To The Starport NOW!" along the lines of "in case of fire, break glass" so that the Canary Run ship can deliver their communications/intelligence to authorities as quickly as possible by physical handoff with the least amount of opportunity for intercept.

But yes, drop tanks + LBB2 do allow some really overpowered low-interstellar-TL ships!

Well, you need to be able to build the L-Hyd drop tanks (type A/B starports) and have enough quality control to reuse them (so they aren't one use disposable, just refurbish and refill) and you're good to go.

And the '77 version of LBB2 takes all the challenge out of it!

Well ... if the XBoats can use those standard drives (that way) and not need a wholesale redesign ...
Won't work with LBB2.81 standard drives+computer though, you're quite correct about that.

 

[Grav_Moped]

Negative.

LBB2.77 drives do not require Power Plant equal or above the Jump number.
Likewise, LBB2,77 drives do not require Computer model equal to or above the Jump number.
As someone pointed out to me previously (in a different thread) ... with unmodified LBB2.77 standard drives you only need enough computer CPU to run the Jump-6 program plus another program (or few) which can rotate through storage.
....

LBB5 explicitly allows building ships with LBB2 drives, but LBB2 does not provide for the use of LBB5 components (though it's a perfectly reasonable house rule to do so). If you're using LBB5 components from any edition (drop or demountble tanks, and you gotta admit those 10Td weapons bays from '77 are pretty nifty), the ship has to be a LBB5 build with LBB2 components, not the reverse -- unless you house-rule otherwise.

This is also true for LBB2 standard hulls. Without house-ruling it, the only way to put LBB5 drives into a LBB2 standard hull is through the TCS "refitting ships" rules, and that gets expensive. (I'd say you can do it, but that's just my opinion.)

 

[Spinward Flow]

but LBB2 does not provide for the use of LBB5 components

Because neither version of LBB5 (79 or 80) existed with LBB2.77 was written.

If you're using LBB5 components from any edition (drop or demountble tanks), the ship has to be a LBB5 build with LBB2 components, not the reverse

Uh ... no.
If that's true, then the Type-J Seeker ceases to exist (see: demountable tanks in cargo bay).

This is also true for LBB2 standard hulls.

Good think I used a LBB2.77 custom hull then.

 

[Grav_Moped]

Uh ... no.
If that's true, then the Type-J Seeker ceases to exist (see: demountable tanks in cargo bay).

Maybe not. It's a valid LBB2 '81 build except for the tank, and that's internal.

Edit: More to the point, it doesn't do anything that you can't do in HG (computer and power plant match Jump drive rating).

 

[Grav_Moped]

Maybe not. It's a valid LBB2 '81 build except for the tank, and that's internal.

Edit: More to the point, it doesn't do anything that you can't do in HG (computer and power plant match Jump drive rating).

And on a Traveller-philosophy note, I've stuffed LBB2 '77 into a parallel universe in my headcanon (and the Day in the Life writing exercise as well).

 

[Grav_Moped]

It does if the computer is a Mod/2, not a 1/bis.

(Re-reading a zombie thread...)
The un-accounted-for 1Td (in the A2 Far Trader in A3: Twilight's Peak) is the Jump Governor out of HG'79. In '81 it wouldn't be called out separately due to being implicit in the Jump Drive. In A3, it being a separate item allows it to be broken (and its repair being the initial objective) without affecting any other drive component...

 

[warwizard]

I did not see this mentioned, wern't drop tanks only allowed on ships built at TL-15 yards? And the answer for the external demountable tanks is you use them on a high jump ship on an aysmetric trade route: 100Dt J-6 ship with 2, 100 DT external demountible cargo pods and a 50 Dt drop tank (retained) does J-1 using 35 DT of jump fuel from the drop tank. Continue retaining the cargo and drop tanks till you are 6 parsecs out on the J-1 main, then J-6 back to starting point expending the drop tank and selling off your de-mountable for use as housing on that backwater world. (sold at the highport). Buy new cargo modules and drop tanks and repeat. Carrying 200DT cargo (actually 194 or so) of vaccuum safe cargo on a 100 DT ship with only 1 crewman (pilot/engineer) makes paying off a J-6 ship easy. The trade and speculation rules make going to lower TL world each jump profitable, and deadhead back using your long legs to avoid 6 unprofitable stops on the way back.
T4 FF&S TL 15: 100DT J6 (7DT) P6, M1, 1/2 stateroom, internal fuel (+14 from drop tank), bridge, computer. (you could carry another 49 DT cargo if you expend the drop tank after topping off the PP tanks before you jettision the drop tank on the J-1 stops) (FF&S 2 the external demountable tanks are armor 10, drop tanks are armor 5 and that takes volume, this is why the cargo totals are less than the CT's 100, or 50 per module).

 

[mike wightman]

TL12 according to 79 HG

L-Hyd Tanks: Disposable fuel tanks which are fitted outside the ship, and drop away before jump. The result is more interior space available for cargo and passengers. Cost: Cr 10 000 plus Cr1000 per ton of fuel. Usable only with jump drives if a special high capacity accumulator is installed (tech level 12; Cr500 000).

 

[Grav_Moped]

TL12 according to 79 HG

IIRC (away from my books at the moment) the cost is Cr10k for the fittings, and Cr1k/Td fuel capacity (plus the fuel, of course). It's in the TCS special rules.

 

[Grav_Moped]

Not positive that the extra cost of the oversized Jump Drive gets balanced out by being able to pull off an Escher Staircase trade route -- but it's not the worst idea I've seen.

Paging @Spinward Flow to the spreadsheet machine, since this is definitely in your bailiwick...

 

[warwizard]

Not positive that the extra cost of the oversized Jump Drive gets balanced out by being able to pull off an Escher Staircase trade route -- but it's not the worst idea I've seen.

Paging @Spinward Flow to the spreadsheet machine, since this is definitely in your bailiwick...

First off the 10k plus 1k/dt for the fittings (60k) is built with the ship and is part of the ship's loan. the extra MCr20 cost is MCr20/120= 2 MCR in additional cost per year total payment per year is MCr3. Just carrying freight 21*196k=MCr4.116 raw income. 915 DT Jfuel, 115 DT PP fuel, and let's say 300 DT fuel for the HePLAR 1330DT fuel total at CR500/DT or MCR.665 crew MCr.096 (pilot6) anual maint MCr.03 giving a raw income after basic expenses 0f MCr.325. Purchasing 8 armor 10 demountable external tanks and 4 drop tanks, selling 6 of the tanks, paying for 8 installs at A-15 and 6 unstalls and selling them at A-9 end the year with 2 100DT tanks installed and one drop tank installed. That is just carrying freight. This ship is intended for trade and speculation route. I am assumming the pilot is the owner aboard and handles the brokering. Been searching for my copy of FF&S 2 not found yet, though did find my stack of my other T4 books, though they had a pancake syurp spill in thier box, good news I was able to remove the syrup and get all the stuck pages apart and un-damaged other than discolorization. The worst damage was on my JTAS #4

 

[Spinward Flow]

Paging @Spinward Flow to the spreadsheet machine, since this is definitely in your bailiwick...

My napkin math research indicates that moving from J1 to J2 capability is a revolutionizing step change in terms of astrogation and routing.

Moving from J2 to J3 is ... really expensive (construction cost, revenue tonnage fraction, etc.) ... and only make sense in regions where you're going to have a LOT of 3 parsec gaps between destinations. If you aren't doing "a lot" of 3 parsec transits every year, you're often times better off using J1+2 via collapsible fuel tanks instead for the "few" times you'll need to make a 3 parsec transit. In a lot of ways, it's "more flexible" (economically speaking) to achieve 3 parsec range via double jumping (J1+2) rather than by single jumping (J3) if your trade route is not requiring a 3 parsec range more than 50% of the time. If you only need to make 3 parsec transits "a few times each year" between annual overhaul maintenance cycles, double jumping (J1+2 using collapsible fuel tanks) is the superior option.

For 4 parsec transits ... J2+2 via collapsible fuel tanks is going to be SO MUCH CHEAPER and affordable relative to any kind of J4 clipper merchant option could possibly be. There's also the added bonus that if you bolt on L-Hyd drop tanks you can potentially extend that range all the way out to J2+2+2 for 6 parsec transits where absolutely necessary (such as across abyss/rift features).

Double jumping does some very interesting things to the economics of starship design, with a lot of knock on effects for how to run operations. J2 with double jumping potential creates a LOT of flexibility for "reach" and routing to "marry up" otherwise distant markets for improved speculative goods arbitrage possibilities.

I know that MOST starship designs (and most stock merchant design) are built around single jumping. In CT, I'm hard pressed to think of another example of a starship capable of double jumping beyond the LBB2 Type-Y Yacht (of all things, but it was a J1+1 capable starship) so the precedent for the notion has a very long history. Collapsible fuel tanks combined with a J2 drive performance yields a remarkably flexible combination that really hits a LOT of "sweet spots" for design, cost and capabilities. Being able to J2+2 across 4 parsec gaps between destinations yields incredible flexibility ... and I would argue ought to have been a design criteria for Express Boat Tenders to be able to "self-deploy" to any destination along the Express Network (of course, that would require a redesign on the LBB S7 Express Tender to be an 800 ton starship, not a 1000 ton starship in order to "fix" that oversight).

Speaking of which, I'm now thinking that if the Express Tenders HAD to be redesigned (using LBB2.81 drives), what I would do is use an 800 ton hull with H/H/H drives (yielding J2/2G/PP2 performance @ TL=10) and give the design 3 hangar bays.

• 2x 100 ton XBoat form factor berths (220 tons required, because 110% for Big Craft)
• 1x 100 ton Scout/Courier form factor berth (110 tons required, because 110% for Big Craft)

So the overall hull dimensions reduce from 1000 to 800 tons and the internal hangar berth "slots" reduce from 4x 100 tons down to 3x 100 tons. Overall, I think that would work out as a much better combination of factors for mission performance reasons.

 

[Krikkitone]

I think the problem with double jumping is the time cost.
The J4/3 ship is more expensive and carries less cargo.
However, the crew salaries, life support, annual maintenance is all paid on a time basis. So most regular traffic between two hogh traffic worlds would be at the jump distance (up till about 3 or 4). Now smaller worlds could provide a benefit for the J2 path.

 

[Spinward Flow]

I think the problem with double jumping is the time cost.
The J4/3 ship is more expensive and carries less cargo.
However, the crew salaries, life support, annual maintenance is all paid on a time basis. So most regular traffic between two hogh traffic worlds would be at the jump distance (up till about 3 or 4). Now smaller worlds could provide a benefit for the J2 path.

Actually, the time cost "penalty" for double jumping isn't that severe ... except when you're needing to do it constantly.

Assuming 8 days per jump (to be conservative) and 6 days per "business week" at destinations:

• Single Jump = 8+6 = 14 days per destination ("two weeks") = 1 ticket
• Double Jump = 8+8+6 = 22 days per destination ("three weeks") = 2 tickets

However, if you're looking at it from a ticket revenues per unit time, you get this answer:

• 1 ticket per 14 days
• 1 ticket per 11 days

So, ironically, the double jumping starship is generating more ticket revenues per unit of time than the single jumping starship.
In other words, there is a ticket revenue "efficiency" to be found in double jumping which is NOT present for single jumping.
After all, when single jumping, 2 tickets requires 14+14=28 days to generate ... not 8+8+6=22 days.

Additionally, more powerful drives require more engineering tonnage, which in turn requires more (engineering) crew positions ... which raises crew salaries, life support overhead expenses and reduces revenue tonnage fraction ... all of which run create headwinds against profit potentials.



So on ticket revenues alone, double jumping is actually an ADVANTAGE relative to single jumping, when looking at the balance sheet exclusively.

Where that assumption is NOT true is when dealing in speculative goods arbitrage. Speculative goods in the cargo hold(s) is owned (temporarily) by the starship operator and generates no ticket revenue from outside the operator's finances. While speculative goods "occupy" cargo hold capacity, that tonnage is "not available" for selling tickets to third parties to generate revenue from external sources.

So in that circumstance, single jumping is better for speculative goods arbitrage (tramp) trading ... but double jumping is better for ticket sales revenues.

I know, it's counter-intuitive ... but that's what a Merchant College education is for.

 

[Grav_Moped]

However, if you're looking at it from a ticket revenues per unit time, you get this answer:

Assuming you get to charge per jump rather than world-to-world, of course. It's easily justifiable as a house rule interpretation. That said, if I'm house-ruling freight/pax rates I'll go with per-parsec rates plus promptness bonuses instead. (That is, rates cover operating expenses for a reasonably-efficient ship of that Jn, but the cargo volume available is reduced proportional to the cost. Someone'll pay for J-5, but they'll be few and won't have a lot to send.)