CT Only: Type QJ False Seeker (100Td, J0/2G)

[Grav_Moped]

The Type QJ appears to be a standard Type S Scout/Courier converted into a standard Type J Seeker through removal of 10Td of fuel tankage, 2 staterooms, and the Air/Raft. It's not.

The conversion (or scratch-build) also removes the Jump Drive, re-configures the maneuver drive* to appear externally to be the Jump Drive, moves 10Td fuel into what used to be drive bay space, and makes 20Td of the (overtly 30Td) fuel tanks into hidden cargo space (or adds hidden staterooms back in, or some combination thereof). There is also a 10Td collapsible tank on board which would enable 2J1 range based on the apparent fuel tank size, if used (which it never actually is) and if it had jump drives (which it doesn't).

The drive bay remodeling costs as though the ship has a non-standard 100Td streamlined hull (maybe less, but that's a referee call).

What's the point of all this? It's a carried craft for a collector-drive ship that is hiding its existence (collector drive discussion thread). By appearing to be jump-capable on its own, it doesn't raise suspicion that it has a parent ship parked out there beyond Jump Limit. Small craft suddenly appearing in-system but not being jump-capable, would make people wonder how they got there -- and maybe go looking around...

In other words, it looks like a mini free trader (up to 2J1/2G) with almost 25Td of cargo space, but is actually a non-jump-capable shuttle with ~45Td of cargo space -- of which 20Td is concealed.


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*or power plant exhaust, depending on what flavor of technobabble you're using in YTU.

 

[AnotherDilbert]

Quite expensive (MCr 39), since it needs a custom hull, but that is perhaps not much of a problem for the use case.

Much cheaper to convert an actual Scout (or Seeker), and lose 10 Dt in the engineering compartment. MCr ~21 if built from scratch with 34 Dt payload:

QJ-12022R1-000000-00000-0       MCr 20,6         100 Dton
bearing                                            Crew=1
batteries                                           TL=12
                          Cargo=34 Fuel=20 EP=2 Agility=2

Single Occupancy    LBB2 design                    34,7      20,6
                                     USP    #     Dton       Cost
Hull, Streamlined      100 Dt          1          100           
Configuration       Cone               2                      3 
Scoops              Streamlined                                 

Engineering                                        10           
Manoeuvre D         A                  2    1       1         4 
Power Plant         A                  2    1       4         8 
Fuel, #J, #weeks    J-0, 4 weeks                   20           
                                                                
Bridge                                      1      20         0,5
Computer            m/1bis             R    1       1         4 
                                                                
Staterooms                                  2       8         1 
                                                                
Cargo                                              34,7         
Collapsible Tanks   30 Dton                 1       0,3       0,0
                                                                
Empty hardpoint                             1       1         0,1
                                                                
Nominal Cost        MCr 20,62            Sum:      34,7      20,6

If converted from a Scout, it can retain the jump drive, and actually do jump on its own; J1 with powered down drives or 3×J1 with collapsible tanks. Only basic difference from a Seeker is 10 Dt concealed cargo? Nothing is more covert than the real thing?

 

[Spinward Flow]

What's the point of all this? It's a carried craft for a collector-drive ship that is hiding its existence (collector drive discussion thread). By appearing to be jump-capable on its own, it doesn't raise suspicion that it has a parent ship parked out there beyond Jump Limit. Small craft suddenly appearing in-system but not being jump-capable, would make people wonder how they got there -- and maybe go looking around...

The collector drive tender isn't going to be "free" on the cost side of things.

My sense is that this approach is more convoluted than it needs to be. Also remember that Seekers required a laser (for mining operations) to be installed, and having a missile rack in the turret makes "too much sense" as a drone launcher for conducting surveys and the like (just swap out the missiles loaded into it for sensor types instead of warhead types).

A FAR better approach to this sort of thing would be to take a stock Type-S design (LBB S7, p15-17 and p46):

1. Swap out the Air/Raft (4 tons, MCr0.6) for a Prospecting Buggy (4 tons, MCr0.75). (Beltstrike, p9)
2. Spend 1 ton (and MCr0.07) to upgrade the default life support package for long endurance. (LBB S7, p16)
3. Reduce internal fuel from 40 tons to 21 tons.
4. Install a Pulse Laser (MCr0.5) and a Missile Rack (MCr0.75) to the (default: empty) Dual Turret.

At this point, you've got 3-1+19=21 tons to play around with, which then gets turned into cargo bay space for the next step.

10 tons of cargo space is considered minimal for ore processing and sample return (Beltstrike, p3), however this can simply be "cargo space" rather than a dedicated laboratory or workshop type facility.

Define the cargo space as being 21 tons and you can put a 20 ton collapsible fuel tank (0.2 tons, MCr0.01) (LBB A5, p13-14) and 120 person/weeks of reserve life support (0.8 tons, MCr0.12) (Beltstrike, p3) into the "spare" 1 ton of the 20+1=21 tons cargo hold. This then leaves 20 tons of cargo hold "flex tonnage" available for either fuel (to jump with) or ore processing (to prospect with) during operations.

In terms of fuel endurance, 21 tons of internal fuel is sufficient for:

1. (21/20*28=29.4) 29 days 9 hours of power plant endurance @ J0.
2. (21-10=11) ... (11/20*28=15.4) 15 days 9 hours of power plant endurance @ J1.
3. (21-20=1) ... (1/20*28=1.4) 1 day 9 hours of power plant endurance @ J2 (insufficient to complete the 1 week jump).

However, since fuel transfers from collapsible tanks to internal tanks "takes about 3 hours" (LBB A5, p13), what CAN be done is initiation of jump and then once in jump a fuel transfer from the collapsible tank to the internal fuel tank can be done, providing sufficient fuel reserve for the power plant to continue operating through to breakout from jump and maneuver to refuel.



In fact, I would even go so far as to say that "updating" the stock Type-S in this fashion (minus the prospecting specific items) "makes too much sense" from an overall perspective. Giving stock Type-S Scout/Couriers 20 tons of "cargo/fuel flex" capacity is an absolute game changer for the range of missions that they can undertake. It just multiplies and magnifies the uses to which they can be put, both in the interplanetary and interstellar contexts.

Of course, being able to do that kind of thing required "expansion of the rules" beyond LBB1-3 through LBB A5 and (in this case) Beltstrike ... but the underlying opportunity IS THERE ... it just needs someone to come along and pick it up.



Going with a collapsible fuel tank approach like I'm doing here would be (I'm thinking ) a FAR superior option to the alternative of needing to build a collector tender ship for interstellar mobility, where the "Seeker" is basically just a Big Craft masquerading as a starship.

To be fair, if you REALLY want to do the Tender+Rider concept ... you're actually better off doing a collector tender plus 50 ton Cutter for interplanetary runabout duties than trying to repurpose a Type-S like you're attempting to do.

 

[Grav_Moped]

First off, just using an ordinary S or J would be simpler and likely cheaper, because the S is underpriced to begin with, and it's probably "pre-owned" too. The idea here is to disguise a cargo craft, though. Building from scratch at 99Td (nobody'd notice) and using a computer and two seats for the bridge would make for a much more efficient cargo hauler if it wasn't intended to be the best-disguised decoy (if you don't look in the drive bay, you wouldn't know).

I used the "power-plant fuel in folding tanks" trick in the courier version of the 6-boat I did up a few years back. Mechanically, there's no reason it shouldn't work -- even the worst-case power plant fuel burn rate is nowhere near the stated fuel transfer rate. At worst, include a 1Td hard-tankage buffer tank to hang a lampshade on. Per RAW, though, it's flatly prohibited. (Friendly wave to AnotherDilbert!)

Playing it semi-straight (still not RAW), have hard tankage for all 20Td jump fuel and 6 Td power plant fuel for 9-10 days. [ETA: should be 7Td, see my following post.] The rest of the mandatory 20Td 4 week PP load goes into collapsible tanks. Only carry the fuel you'll actually use on the trip and the rest can be cargo.


Edited for clarity.

 

[Spinward Flow]

Actually, let me amend my above musings to adjust the mix ever so slightly so as to achieve a 25 ton cargo bay "free and clear" with a fraction of a ton added for a 20 ton collapsible fuel tank and slightly over 20 tons for internal fuel tankage. The way to do this is to drop the Air/Raft berth ... but you can always stow a 4 ton Air/Raft into a 5 ton cargo bay expansion.

Why go to the effort of doing that?
Courier = X-Mail = 5 tons of cargo space allocated to a Mail Vault

Pretty sure that I can shoehorn that all in to make a "better" Type-S2 standard as an LBB2 starship design that borrows collapsible fuel tanks from LBB A5.

 

[Grav_Moped]

ETA....

Edited for clarity

Was off by a ton or so of power plant fuel (needs 5.5Td for a 10%-overlong jump, 1.5Td for 2.2 days transit to/from jump limit, total of 7Td PP fuel in hard tanks, not 6).

Edit to add: make it only 2 days transit fuel and the 0.13Td for the collapsible tank fits into that 7Td too.

 

[Grav_Moped]

And all this is a bunch of hackery to get around the silly non-proportional 10Td per Pn for 4 weeks fuel rule from LBB2. (LBB5's 1%/Pn makes it not worth the effort.) Rules as written, though...

 

[Spinward Flow]

And all this is a bunch of hackery to get around the silly non-proportional 10Td per Pn for 4 weeks fuel rule from LBB2. (LBB5's 1%/Pn makes it not worth the effort.) Rules as written, though...

Fun thing is that for a 100 ton form factor, LBB5.80 custom drives are actually SMALLER than LBB2.81 standard drives.
LBB2.81 = 10+1+4 = 15 tons (engineering) + 40 tons fuel = 55 tons of hull + 20 tons (bridge) + 1 ton (model/1bis) = 76 tons
LBB5.80 = 3+5+6 = 14 tons (+1 waste ton engineering) + 22 tons fuel = 37 tons of hull + 20 tons (bridge) + 1 ton (model/1bis) = 56 tons

The trick is (though) that LBB2.81 scout drives do not require refined fuel ... while the LBB5.80 drives do.

LBB5.80 = 56 tons hull + 7 tons (fuel purification plant) = 63 tons

So the LBB2.81 drives (and default fuel) leaves 24 tons available in a Standard 100 ton hull (not including staterooms, fire control, etc.).
LBB5.80 drives (and default fuel) leaves 44 tons available in a Standard 100 ton hull (not including staterooms, fire control, etc.).

The big difference between these two options is tech level (LBB2.81 = TL9, LBB5.80 = TL11) ... and cost.
LBB2.81 Jump-A = MCr10
LBB2.81 Maneuver-A = MCr4
LBB2.81 Power Plant-A = MCr8
= MCr22

LBB5.80 Jump-2 = MCr12
LBB5.80 Maneuver-2 = MCr3.5
LBB5.80 Power Plant-2 = MCr18
TL=11 Fuel Purification Plant = MCr0.034
= MCr33.534

This means that functionally, you are looking at a surcharge of MCr11.534 (base cost) for a 13 ton rebate when switching to custom drives.

If you take that analysis of alternatives one step further with the 90% volume production cost (LBB2.81) compared to 80% volume cost (LBB5.80), you get the following results for the engineering (which is the supermajority bulk of the expense in construction):
22 * 0.9 = 19.8
33.534 * 0.8 = 26.8272

26.8272 - 19.8 = MCr7.0272 for 13 tons

In other words, the LBB5.80 custom drives make for "a better FIT" inside the (same) hull, but you're paying a premium for the privilege of doing so (~20-25% extra final cost and +2TL) relative to the LBB2.81 alternative.



For me, the really compelling reason to go with the LBB5.80 alternative is that after adding in 4 staterooms (16 tons) and 1 ton of fire control for the turret, you've still got 20 tons remaining to play with ... which is an almost ideal size for a cargo hold that can have a 20 ton collapsible fuel tank stored in it (19.8 tons cargo capacity when the fuel tank is not in use). This means that WHEN NEEDED, such a ship can perform 2J2 on internal + reserve fuel in order to "self deploy" across 4 parsec "rift gaps" at various points along the XBoat network.

When you don't need that much range/endurance for the ship's mission assignment, the 20 ton cargo bay can be quickly (and easily) repurposed for other mission sets (X-Mail courier, Air/Raft for surveys, reserve life support for extended loiter away from base support, etc.).

So a little more expense up front to get the custom drives, but a lot of back end flexibility in deployment options.



Ironically, the collapsible fuel tank "twiddle" that I outlined above around LBB2.81 standard drives achieves almost the exact same thing ... but not quite, due to the higher fuel consumption of the standard power plant (5 tons per week instead of 0.5 tons per week).

 

[Grav_Moped]

Ironically, the collapsible fuel tank "twiddle" that I outlined above around LBB2.81 standard drives achieves almost the exact same thing ... but not quite, due to the higher fuel consumption of the standard power plant (5 tons per week instead of 0.5 tons per week

While we're on the topic of ironic amusement, it's worth noting that the "mechanically mandatory minimum plus folding tanks" scheme requires less permanently obligated fuel space than the "Yacht Loophole" (2 weeks worth).

 

[Condottiere]

Sounds like a refurbished scrapped Scoutship, with someone salvaging available power plant and manoeuvre drive from the junkyard.

 

[Spinward Flow]

​

Scout/Courier
Ship Type: SP (Scout, Provincial)
TL=9 (hybrid LBB5.80 design fitted with LBB2.81 standard hull, drives and off the shelf weaponry) (LBB5.80, p18)

Tonnage (standard hull): 100 tons (MCr2) (LBB2.81, p13 and p22)
Atmospheric Streamling and Fuel Scoops (MCr1) (LBB2.81, p15)
Armor: 0

Engineering Compartment (15 tons)
Jump-A (code: 2, 10 tons, MCr10, TL=9, Scout, Capacitor storage: 1 tons = 36 EP maximum)
Maneuver-A (code: 2, 1 ton, MCr4, TL=9)
Power Plant-A (code: 2, 4 tons, MCr8, TL=9, EP: 2, Surplus EP: +0 @ Agility 2, Emergency Agility: 2)
Total Drives: 10+1+4 = 15 tons
Waste Space (Engineering Compartment): 0 tons

Main Compartment (85 tons)
Fuel: 21 tons = 0 + 21 tons (LBB2.81, p14-15, 23)

• Jump Fuel = (Tonnage/10) * Parsecs tons
  • 0 tons = 0 parsecs @ 100 tons
• Power Plant and Reactionless Maneuver Fuel = (10Pn * days/28) tons
  • 21 tons = 29 days 9.6 hours @ 2G M-Drive reactionless maneuver within 1000 diameters of gravity wells for 400 tons displacement

Bridge (20 tons, MCr0.5)
Computer: 1bis (Code: R, 1 ton, MCr4, EP: 0)
Hardpoints: 1 (MCr0.1) (LBB2.81, p15, p23)
Dual Turret: 1 (1 tons fire control, MCr0.5) (LBB2.81, p23)
Weaponry: none installed

External Docking: 100 tons capacity Ordinary Launch Facilities (0 tons, MCr0.2, Scout/Courier becomes unstreamlined while in use) (LBB5.80, p32) (LBB A5, p14)

Crew positions minimum skills required: 1 crew (Cr6000 per 4 weeks crew salaries)

1. Pilot-1 = Cr6000

Staterooms: 4 single occupancy (16 tons, MCr2)

Collapsible Fuel Tank: 25 tons capacity (0.25 tons, MCr0.0125) (LBB A5, p13-14)
Cargo Hold: 25.75 tons (Mail Vault or Air/Raft berth installation ready)
Waste Space (Main Compartment): 0 tons

Total Cost (starship only, not including vehicle and sub-craft)
MCr32.3125 (100% cost single production)
MCr29.08125 (90% cost volume production) (LBB2.81, p18-19)