Yep, drop tanks make a big difference. It's a nifty design -- and for the Boughene-Regina run, the 6G maneuver drive is particularly useful: each world is a gas giant's satellite with a correspondingly deep gravity well and distant Jump Limit.Since you @Grav_Moped objected to the idea of using LBB2.77 drives in a 100 ton hull at TL=9 to achieve Jump-6 performance with L-Hyd drop tanks as detailed over here for the Canary Run ... I figured I might as well take a second stab at the issue using a TL=12 200 ton hull from LBB5.80 with LBB2.81 standard drives installed into it (Power Plant-6 is an absolute killer for fuel on small ships).
The biggest problem is that Jump-6 plus Power Plant-6 in a 200 ton hull requires 120 tons of jump fuel plus 60 tons of power plant fuel. That's 180 tons of fuel in a 200 ton hull if all the fuel is internal ... and you still need room for the drives themselves, bridge, computer model/6 ... crew staterooms (pilot, engineers, medic required ... navigator, steward, gunners optional) ... and there's just no way to make everything fit internally.
But if you use L-Hyd drop tanks to push some/all of the jump fuel requirement external to the hull, it can be made to work.
So ... yet another counter-proposal.
LBB2.81 ... 200 ton TL=12 J6 Business Courier
Total tonnage = 65+6+60+1+20+7+16+25 = 200 tons (wasted space: 0 tons)
- 200 ton custom hull, atmospheric streamlining = MCr22
- Jump-F (6), Maneuver-F (6), Power Plant-F (6) = 35+11+19 = 65 tons, MCr132
(EP:12 in LBB5.80)
- Fuel Purification Plant: 200 ton capacity = 6 tons, MCr0.032 (LBB5.80, p27 and p36)
- Refines 1 ton of unrefined gas fuel per 1 minute (120+60=180 minutes/3 hours total with L-Hyd drop tank installed)
- Refines 1 ton of water fuel per 10 minutes (1200+600=1800 minutes/30 hours total with L-Hyd drop tank installed)
- 60 tons of internal fuel (power plant only, 4 weeks/28 days endurance, 24 weeks/168 days powered down)
- 120 ton external L-Hyd drop tank (Cr130,000 new/empty, Cr12,000 reuse/empty)
Drive performance reduced to Jump-3, Maneuver-3, Power Plant-3 while drop tank is retained.- Triple Turret: Sandcaster, Pulse Laser, Missile = 1 ton, MCr2.5 (EP:1 in LBB5.80)
- Bridge = 20 tons, MCr1
- Computer model/6 = 7 tons, MCr55 (EP:5 in LBB5.80)
- Staterooms: 4 = 16 tons, MCr2 (20 person/days life support per stateroom)
- Crew (4): Pilot-2/Gunnery-2, Engineering-1 (chief), Engineering-1, Medic-1
- Cargo: 25 tons (5 tons mail vault, 20 tons cargo)
Total cost (first in class) = MCr214.662 (including new L-Hyd drop tank construction cost), 48 weeks construction time (LBB A5, p33)
10% discount volume production cost = MCr193.1958, 44 weeks construction time
Recurring overhead expenses per jump on a 12 day cycle on the Canary Run:
Total costs per jump = Cr23,833 per 12 days
- L-Hyd drop tank rental: Cr12,000
- Berthing Fees: Cr100
- Life Support: Cr100 per person per day / Cr4800 per 12 days
- Crew Salaries: Cr16,175 per 28 days / Cr6933 per 12 days
Revenue generation per jump:
Net profits per 12 days = Cr1167 profit (mail only, no cargo) to Cr21,167 profit (mail, 20 tons cargo)
- 5 tons mail: Cr25,000
- Cargo Transport: Cr1000 per ton (max Cr20,000)
Net profits per 12 days with 50% subsidy rake on revenues = Cr11,333 loss (mail only, no cargo) to Cr1333 loss (mail, 20 tons of cargo)
Basically a high priced "business jet" type of fast transport that isn't expected to make much of a direct profit on starship operations (and certainly not enough to earn back the construction cost over 40 years).
Although there shouldn't be much trouble filling the cargo hold (20 tons of cargo would be pathetically easy to come by reliably on the Boughene to Regina route of the Canary Run) ... even with full manifests of mail and cargo to transport, annual revenue generation on 30 jump cycles of 12 days each (so 360 days, just in time to return to home base for annual overhaul maintenance!) would deliver a maximum of Cr440,374 in profit per year after all expenses (including annual overhaul maintenance) have been paid for if the ship is not operating under a subsidy. With a subsidy ... ship operations are simply a money pit, generating deficits on every jump.
So basically you buy and crew one of these ships to lose money (just like most business jets), since Cr440,374 per year amounts to a maximum of MCr17,614,960 over 40 years ... which is less than 10% the cost of construction for even a volume production version. Therefore, the return on investment with ships of this class would have to come from transport of high value speculative cargoes and the privileged information carried in the mail vault that would lead to economic deals and opportunities "external" to the operation of the ships on the Canary Run themselves.
The 20 ton cargo bay (not including the 5 ton mail vault) is a useful size for transport of high value cargoes, up to and including "modular offices" for business executives (4 staterooms plus 1 workshop is enough for 2 business associates, 2 secretary/stewards and a shared office space workshop that the business associates can each use during time in jump to continue working while en route). I figure that such 20 ton "modular offices" would be a relatively simple pre-fabricated design that can be rented by persons of sufficient means (and social standing and security clearance) to be loaded into the cargo bay of a Canary Run courier for a "fast business trip" between Boughene and Regina so as to facilitate coordination between interests at Boughene and the subsector capital.
20 ton hull, configuration: 4 close structure = MCr1.2 (LBB5.80)
4 staterooms = MCr2
1 workshop = MCr0.5
Total cost (first in class): MCr3.7
80% discount volume production: MCr2.96
Alternate configurations would be available, of course, but that gives you an idea of the variety of possible items to transport that can make a cargo bay more than just merely a cargo bay. Just slide the "modular office" into the cargo bay and you're ready for transport. The "modular office" can also continue to be used at the destination until your business dealings have been completed, at which time the "modular office" can be loaded right back onto another Canary Run ship for the return trip.
Note that a similar setup can be used to transport personnel who want to maintain a low profile and need cover stories (such as intelligence operatives) as well as other adventure hook scenarios.
The reason for the Maneuver-6 in addition to the Jump-6, Power Plant-6 is because the difference between Maneuver-2 and Maneuver-6 is the difference between a Maneuver-B drive (3 tons, MCr8) and a Maneuver-F drive (11 tons, MCr24) ... which all things considered is a pretty minimal/marginal difference in a J6 Courier ship (that is designed for SPEED rather than for direct mercantile PROFIT). Unlike LBB5.80 custom maneuver drives, with LBB2.81 standard drives it is possible to "pile on" the maneuver capacity relatively cheaply (in terms of tonnage needed).
From a LBB5.80 USP perspective, the ship would have a standard Agility=3 powering the pulse laser (EP=1) and model/6 computer (EP=5) ... but an Emergency Agility=6 if the pulse laser is powered down (which in a Break Off By Acceleration situation would be an excellent idea to avoid an unwanted intercept).
1x TL=12 Sandcaster = 1 battery code: 3
1x TL=12 Pulse Laser = 1 battery code: 1
1x TL=12 Missile = 1 battery code: 1
Hardly a scary prospect until you realize that model/6 computer does extremely nasty things with to-hit rolls (offensively and defensively) under LBB5.80 combat rules. LBB2.81 starship combat rules, particularly with extensive computer programs running, are ... different.
So ... there you have it, @Grav_Moped.
If you didn't like my 100 ton TL=9 LBB2.77 version (which was about 1/3rd the price of this beast) ... here's an alternative using LBB2.81 for you that relies on L-Hyd drop tanks and a fuel purification plant to make it almost break even economical in a paid off condition.
If you want to get really cute, make it 199Td (the hull's custom anyhow) and you don't "need" the engineering crew. (Well, the rules say you don't, but this thing's rocking a full set of Size F drives and probably should have a couple of techs back there despite the rules.)
For my own reasons*, I'm still going with the Israfel-class 400Td courier in my narrative, but others using this thread for ideas about Boughene as a setting should definitely consider it.
------
* Narratively, I needed Jump-6 without drop tanks because it'd be really awkward for the PC party to have to reroute such that each Jump layover point would be able to supply drop tanks.
In-universe explanation:
The Israfels were proof-of-concept on the Canary Run, with the expectation that the Duke of Regina would rapidly replace them with state-of-the-art couriers under his control and on his dime (which he did). However, they were really built for the Pretoria Doomsday Alert Shortcut (the Canary Run was just the official justification/pretext to get them funded), and for that they needed to be able to operate without external logistical support.
Last edited: