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T4 merchant design challenge

warwizard

SOC-13
OK this is for the gearheads. Here are the rules:
Rules Trade and speculation + local Cr derated by starport and tech level. T4 FF&S
Technology: Any class A or class B Imperial starport in the Spinward Marches or Trojan Reach sectors. Starport must have the ability to build your hull. If a class B, the jump drive must be imported paying 1000Cr/parsc/DT to ship it.
Hull : 100DT to 199DT only. May be of any configuration or streamlining or material available at the constructing starport. External cargo pod is allowed, these are bolted down (House rule) (explosive bolts allowed) no grappel required unless you intend to provide services like power or air to the external cargo. A flexible jump mesh is allowed, however the volume is limited by the DT of jump drive installed (DT drive/enclosed DT>=2%) You may install environmental gravity to a limited volume such as crew quarters only, crew, controls, and engineering only, all except fuel tankage. Attached cargo pods and drop tanks changes your configuration to dispersed. If you use grappels for cargo pods, an interesting thing is to put a small power plant and a minimal maneuver package aboard the pods to maneuver them to the high port (with coms and a remote control station).
Maneuver Drives: You are not required to mount 1G+ maneuver drives, however your transit times will be taken into account based on acceleration=loaded mass in mt/thrust in mt/10. Lighter services are available at A through C ports. High ports are available at all AS systems other than X and all A and B ports. Systems with red giant or simular sized primaries will have a highport at the 100D point of the star. Default Maneuver drive is the HePLAR if you are using a fusion power plant. Thruster plates and antigravity drives makes you detectible by gravetic sensors see erratta. Fusion rocket, ramscoop, and deadaelus drives require a non radioactive secondary thruster or a tug for entering and leaving dock, (most systems will require you to utilize lighters with a hazard bonus.)
Jump drives: Drop tanks require the jump drive to have been made at a TL 15 or higher system with a shipyard. Replacement tanks can be made at any A or B starport. The capacity of the tanks will vary as the material toughness is changed, plan for this when allocating your fuel tankage. Jump drive capacity may be designed to jump more than the ship's hull volume. The TL of the Jump drive sets the maximum J-N possible, the current displacement tons determines the maximum jump if the drive is capable of that jump number Example: TL 10 drive with 20DT in a 100DT hull could perform J-1 with 900DT of external cargos attached (1000 gross DT), still performs J-1 at 100 gross DT. A 7DT, TL 15 drive can J-6 in a 100DT hull(151.2MW, 60DT fuel) or J-1 at 350DT(88.2MW, 35DT fuel), J-2 at 233DT(117.4MW, 46.6 DT fuel), J-3 at 175DT(132.3MW, 52.5DT fuel), J4 at 140DT(141.1MW, 56DT fuel), and J5 at 116DT(146.2MW, 58DT fuel). The power must be provided continually till the jump bubble collaspes.
Power plants: Piezo Nuclear fusion (TNE FF&S1) (PNF), Fusion+ is allowed, Fusion is allowed, Fission is allowed, Antimater is not available in the area. Scale efficiency is not applied to PNF plants, and they do not have a minimum size. Scale efficency is not applied to Fusion+
Fuel: Jump fuel sufficent for 1 Jump-1 must be carried inside the base hull, as well as a minimum of 30 days of whatever fuel the power plant(s) use. Please review JTAS alerts for worlds that do not allow wilderness refuelling. Drop tanks can be obtained within 1 week at A and B highports for spherical configurations, other configurations available but may require previous contact and payment. Throw 2d6 - pop <4 for immediate availability -2 if you have jetisioned your "special" drop tanks here previously. Please note: Heavy water and duterium are not commonly available in Spinward Marches and Trojan Reach Imperial worlds in 1105, and are subject to contracted deliveries at A through C ports. (place fuel contracts while your ship is under construction)
Communications: Carry both laser and radio 1000AU range systems. One additional 500,000KM range radio is required for ships that are under mortgage.
Sensors: MK1 eyeballs are not good enough. Install something reasonable, your lender may have suguestions.
Controls: At least one workstation, a workstation or crewstation per each required crew.
Computers: Three are required. These are cheap in T4, and help you reduce your required crew.
Automation level: Spinward Marches/Trojan Reach in 1105 you make your choice.
Weapons: Required only if you are going to take on a mail contract.
Life support: Class 3 minimum. Coverage of volume of drives, acomodations, electronics, and weapons is required. Other internal spaces is optional. Airlocks must be installed to access these non life supported internal spaces.
Environmental gravity: You have to cover at a minimum, the accomodations space. Crew need to have gravity or suffer adverse health effects over time.
Budget: You have 12MCr(IMPCr) for any drives purchased elsewhere and shipped in and for your 20% down payment.
Loan Terms: 20% down 240 payments of 1/120 th of purchase price in LOCAL CREDITS of the building shipyard!!!!!

Discussion of the rules are welcome and rules may change as a result. I intend to do a second design challenge for Terra TL-9 era prior to contact with the Imperium.
Edit: left off the example J-6 fuel usage of 60DT.
 
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OK First submission:
Main ship built at Glisten yards drop tank craft made at Aki J-1 away with imported computers and power plants. Cargo pod made at Aki.
Trade run is J1 from Glisten using internal fuel and 10DT disposible drop tank, mounting nothing, carrying modular power plant HePLAR drive, and computers for the drop tank craft that Aki is building. Return to Glisten and repeat till the drop tank and cargo pods are ready. Then it is pick up and mount the cargo pod, the drop tank craft grapples the ship, tops off the internal tankage and is retained through jump, gives the main ship delta V for meeting the main trade center, then detaches and proceeds to the gas giant skims and refines the fuel and meets back up to the main ship at Glisten port, reattaches and the pilot takes liberty. Meanwhile the cargo pod is detached, a local broker is hired to sell the load of raw materials imported from Aki, and obtain trade and speculation cargos bound for Aki to be loaded into the pod and have the pod ready for pickup in two weeks. Jump for Aki with the drop tank craft only, at Aki pick up the second cargo pod loaded with raw materials offload contract cargo attach the drop tank craft and jump for Glisten, swap out the cargo pods deliver internal cargo meet the now refuellled drop tank craft pick up internal cargo speculative trade goods from the broker, jump to Aki hire a broker in Aki give her the full cargo pod, and load of internal cargo, pick up a third cargo pod load bulk raw materials internal and cargo pod, meet the drop tank craft and jump for Glisten.
Now the tempo picks up, instead of spending a week at each port, only three days is needed for each port visit giving a 3 jumps every 30 days, as the broker has the internal cargo and pod already purchased/booked and ready to be loaded/grappeled, and the drop tank craft has three days to skim fuel from the gas giant.

Short description of the three designs:
Jump tug: TL 15 100DT unstreamlined sphere, armor 20, J1, internal jump fuel tankage 1.1 DT, provision for 1 10 DT drop tank unstreamlined, minimal Maneuver drive of .1m3 HePLAR drive, 1 DT internal maneuver fuel. Internal Fusion power plant only able to power J1 at 100 DT Note: Jump drive is 10 DT and is able to J-1@ 500DT with the support of the drop tank craft's onboard power. 2 airlocks 2 large cargo hatches, life support IV covering 90DT, Gcomp 20DT two half staterooms, crew 2, owner aboard and fuel tank/cargo pod pilot. Internal cargo tankage is estimated to be 80 DT. Can J-1 with internal tankage and 10DT drop tank retained.

Cargo pod: TL 9 300DT unstreamlined sphere armor 20 .6m3 imported modular TL-15 Fusion power plant 3.6 MW, .1m3 HePLAR 200kN TL-15 maneuver drive Laser comm 30,000Km range 2 TL 15 Flt computers one remotely piloted crewstation no internal Gcomp or life support, one airlock, 10 large cargo hatches. Grappel for 100DT unstreamlined sphere with fuel and power connections, 1 DT maneuver fuel. Internal cargo estimated at 280DT

Drop tank craft TL9 100 DT hypersonic airframe cylinder Armor 20, 20m3 modular imported Fusion power plant with 10% scale efficency above 6m3 256mt 128.4MW 6MCr imported TL 15, 12.0m3 HePLAR drive 12mt .12MCr 24,000kN 30m3/hr Lhd fuel. Gcomp using imported TL 15 modules for 6g compensation only for the 1 workstation, no life support 1 airlock, 2 flt computers TL 15. Basic sensors and communicators. Grappel for 100DT unstreamlined sphere, grappel is streamlined goal is 50 DT jump fuel, any extra tonnage is applied to maneuver fuel. Refinery for purifying jump fuel in 2 days imported TL 15. Note: if this design is too tight, I will build it at Glisten to save internal volume due to armor toughness.

Discussion: Once operational tempo is obtained the ship delivers a 360DT shipment of brokered trade and speculation cargo or contracted cargo every 10 days. (80 DT has life support, the rest must rely on the shipping container if pressure is required.) 1080 DT of cargo per month. As both worlds have populations of 2, and 8 billion and are HI IN (As TL F for Glisten, and Po TL 9 for Aki) The TL difference makes trade and speculation cargos into Aki from Glisten extremely profitable, and Aki's level H resourses makes bulk resourses a constant cargo needing shipping into Glisten, while there may be the ocasional speculative cargo that may make a profit in excess of shipping and broker costs. Another possible change is to use a 400DT cargo pod, carry a larger power plant in the main ship, and have two cheaper drop tank crafts one in each system. Once I get spreadsheet access again I will build out the three designs in greater detail. (Dog chewed apart the video cable for my old monitor that goes to my old desktop, using a steam deck (Linux system) to post this, no spreadsheet there.)
 
OK going to try designing the ship here, just using brain to finger interface. First posting hull and major drives & plants.

Hull 100 DT bonded superdense armor 20, sphere, unstreamlined, 2 airlocks, 2 large cargo pods ,1 10.01DT drop tank grapel for custom 10.01DT Drop tank sphere, unstreamlined.
Armor: Enhanced Bonded superdense factor 20 for 1400 m3 hull no mods for configuration sphere
area 605m2 Diameter 13.9m structural factor .233 toughness 47.1 density 15mt per m3 armor 20/toughness =.4246cm hull thickness area 605m2 times .004246m = 2.569m3 of armor in the hull plating mass is 3.553mt cost .08MCr. Internal structure: We are going to design for gmax=2 so 2 times SF of .233 /47.1= .0099m3 .1484mt. Damn, that is cheap looking at gmax=6 .03m3, .45mt 93 credits
-Total armor 2.87m3 43mt .089MCr -.00287MW gMax=6
2 airlocks 6m3 .4mt -4m2, -.002MW .01MCr
2 large cargo doors -40m2 .04MCr Note( no cargo handling equipment as will always be at class A ports.)
2 small staterooms 56m3 4mt -.001MW .08MCr
Grappel for 10.01 DT drop tank dia 6.44m -50% mod to area, so 6.44*6.44/2 =20.74m2 volume is .01m3 per m2 .2074m3 cost mod is 15% of .001MCr per m3 or .031MCr
Coatings bare metal cost -.005MCr*605=-3.025MCr errata for pp.65.

Totals for hull so far: Volume available:1334.9226m3 Mass: 47.6074mt Area available: 540.26m2 Power -.00587MW Cost:-2.775MCr, yes they are paying me to not have advertizing on my hull.
Life support IV air and water recycling food additional, gcomp 6g 1 workstation 1 crewstation
Life support for 1348m3: 21.568m3 .3235mt .021568MCr -.021568MW
Gcomp for 1362m3: 2.043m3 .04086mt .10215MCr -1.43MW
Food storage: minimal galley with good quality meals 3 weeks for two persons 15l day 72Cr per day.
Food storage for 3 weeks .331m3 .02152mt -5KW 1324CR
1 year of TL-15 emergency rations 2 people @ 1 ration per day 1.05m3 1.05mt .073MCr
1 workstation 14m3 .2mt
1 crewstation 3.5m3 .2mt
Automation standard -.105MW .21MCr
 
3 computers CM .6 CP 1.6 TL 15 .015m3 .003mt -.0129MW .0012MCr
Edit: graple now mounts 11DT tank increase M3 by .03
Totals so far: Available volume: 1293.436m3 Mass: 49.4247 Area available: 540.26m2 Power: -1.567MW Cost:-2.367MCr

power needed to J-1 @1554m3 *.018=27.972MW (power needed to J-1 @7000mt, 126MW)
Internal power 4.9m3 9.8mt .03m2 .98MCr 29.4MW Fusion .00034m3/hr LHg fuel
3m3 pp fuel for 365 days .214mt
HePAR .1m3 .1mt .1m2 200KN -1MW .001MCr .25m3/hr LHd fuel 56 hours per 14m3
Fuel 14m3 1mt
Jump drive 140.m3 280.mt 37.035m2 42MCr (126MW to jump volume 7000m3, 500DT)
Jump fuel internal .14m3 .01mt
Totals so far Volume available:1131.296 Mass: 341.5387mt Area: 503.096 Power:-1.139MW Cost40.614MCr
Note: drop tank retained in intial config, pumps for jump by powering down maneuver OR gcomp. 79.81DT remain, still need to add coms and sensors. Not retaining the 10.01DT drop tank saves about 2.5MW then can reduce internal pp by another .4m3, but then I have to buy drop tanks each jump till I get the drop tank craft built. Have to think a bit more on this. Nope too much of a chance I get held up waiting for drop tanks. Will jump retaining the tanks and go below intended cargo. Next posting sensors and coms. Edit: Can increase the drop tank to 11DT, and not carry internal jump fuel lose a bit (.03m3 on the grapple) gain 14m3 another -14*.018 MW -.252MW for jump, ok doing that. Now have .8DT for sensors and coms. Now I have to power down Gcomp while in jump.
 
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Coms and sensors and have 11.2m3 for all of them.
Coms first: 1000AU radio .05m3 .025mt 200m2 .2MW .15MCR
1000AU laser .015m3 .03mt 1m2 .003MW .18MCr
Not too bad there.
Sensors PEMS first 13.0 sensitivity PEMS array
.5m3 .1mt .5m2 .0005 MW 2.5MCr
No trackers, no active sensors, no anything else.

Finally: 80DT internal cargo 1120m3
ship's locker 10m3

Totals 0.7m3 remaining discarding it as rounding errors
allocating 10mt/m3 as max mass in cargo (expect to be carrying metal ingots a lot of trips)
Mass Max 11,542mt internal thrust 200N aproximately 1m/s every 400s 1 g every 1 Hr 11 min 56hrs/1.2 hours or 47gs total impulse. More reasonable times/acceleration curves if I do not carry max mass.
Area 301.5m2 available.
power -1.3425 (gcomp is -1.4, so can still use maneuver, and coms and sensors while pumping for jump.)
Cost 43.45MCr
Budget 12MCr down payment 8.6888MCr remaining 3.3112 MCr
Payment: .362083MCr per month for 240 months. Next up is the 100DT drop tank craft.
 
100DT drop tank craft design goals: 98MW to main ship to pump for jump, 9.8m3 HePLAR 19600kN 50DT jump fuel, 12.5% of surface for fuel scoops to fill tanks in 1 Hr. refine 700m3 fuel in 24 hours Hull must be able to enter gas giants to scoop fuel at high velocities. Solve for maximum maneuver fuel while meeting other goals.

Power plant 15.4m3 30.8mt .098m2 98.04MW 4.62 MCr Cannot buy this drive and ship it to Aki right now, I have to build the whole thing at Glisten. Sorry Aki have to build the expensive craft at Glisten.
9.8m3/year fuel
HePLAR 9.45 m3 9.45mt 9.45m2 -94.5MW .945MCr 18900kN
Maneuver fuel (variable)
Jump fuel 700m3 50mt
Fuel refinery 24 hours .05m3 per m3 of fuel refined. 35m3 70mt -3.5MW .026MCr
Fuel scoops 12.5% of surface area.
Going to need an active scanner for the gas giant scoping runs

Crunch time Volume available: 630.35m3 (45DT) Mass: 160.25 Area: varies Power .04MW Cost 5.096MCr
 
Active sensor 5m3 10mt 1m2 1MW 2MCr sensitivity 11.5 range 500,000km
passive sensor .5m3 .5mt .5m2 .0005MW 2.5MCr sensitivity 13 range 5,000,000km
1 workstation 7m3 .2mt
1 airlock 3m3 .2mt

1000AU radio .05m3 .025mt 200m2 .2MW .15MCR
1000AU laser .015m3 .03mt 1m2 .003MW .18MCr

gcomp 6g for just the workstation (7m3)*.0015*6=.063m3 .126mt .0441MW .00315MCr
minimal life support 8 hour endurance (once the scooping run is in progress the stale air is flushed and fresh is bled from the fuel purifier.)
Low automation, this craft is operated by pilot aboard, there is very little actual life support coverage it is expected that the operator will have vacc suit with spare bottles and a couple of emergency rations in case the mission runs long (assumming scoop run replenishes LS consumables, and vacc suit has 8 hrs of air max endurance 24 hrs.)
Life support minimal for just the workstation 7m3
Automation is not including the Jump fuel tankage or waste volume (70DT of 100DT)
OK Hull configuration and streamlining. We are going to put the grapples on the cargo pod I cannot manage a grapple for 100DT and still have maneuver fuel. This also requires that one of the 300DT cargo pods is built at Glisten.
TL 8+ hypersonic with airframe cone 30% waste volume of 1000m3 hull. Surface area mod 1.28 Cost mod 1.1
Base values vol 1400, L 13.9 area 605m2 (-300m3 774m2 (waste area 45%)) airframe cost mod 1.2
Hull area 774m2 armor 20 toughness 47.1 6g rated internal structure mod .233
hull plating 3.2866 m3 49.3mt .0032866MW .1345MCr
internal structure .0297m3 .4452mt 3W 92Cr
Hull coatings non-black discount of .00005MCR per m2 774*.00005 -.0387 MCR
(Error on posting #3 "Coatings bare metal cost -.005MCr*605=-3.025MCr errata for pp.65."
line should read: "Coatings bare metal cost -.00005MCr*605=-.03025MCr errata for pp.65."
 
edit of last page
Active sensor 5m3 10mt 1m2 1MW 2MCr sensitivity 11.5 range 500,000km
passive sensor .5m3 .5mt .5m2 .0005MW 2.5MCr sensitivity 13 range 5,000,000km
1 workstation 7m3 .2mt
1 airlock 3m3 .2mt -2m2

1000AU radio .05m3 .025mt 200m2 .2MW .15MCR
1000AU laser .015m3 .03mt 1m2 .003MW .18MCr

gcomp 6g for just the workstation (7m3)*.0015*6=.063m3 .126mt .0441MW .00315MCr
minimal life support 8 hour endurance (once the scooping run is in progress the stale air is flushed and fresh is bled from the fuel purifier.)
Low automation, this craft is operated by pilot aboard, there is very little actual life support coverage it is expected that the operator will have vacc suit with spare bottles and a couple of emergency rations in case the mission runs long (assumming scoop run replenishes LS consumables, and vacc suit has 8 hrs of air max endurance 24 hrs.)
Life support minimal for just the workstation 7m3 .007m3 .014mt 14Cr
Automation is not including the Jump fuel tankage or waste volume (70DT of 100DT) 420*.000075MW=.0315MW 420*.000150MCr=.063MCr
OK Hull configuration and streamlining. We are going to put the grapples on the cargo pod I cannot manage a grapple for 100DT and still have maneuver fuel. This also requires that one of the 300DT cargo pods is built at Glisten.
TL 8+ hypersonic with airframe cone 30% waste volume of 1000m3 hull. Surface area mod 1.28 Cost mod 1.1
Base values vol 1400, L 13.9 area 605m2 (-300m3 774m2 (waste area 45%)) airframe cost mod 1.2
Hull area 774m2 armor 20 toughness 47.1 6g rated internal structure mod .233
hull plating 3.2866 m3 49.3mt .0032866MW .1345MCr
internal structure .0297m3 .4452mt 3W 92Cr
Hull coatings non-black discount of .00005MCR per m2 774*.00005 -.0387 MCR
(Error on posting #3 "Coatings bare metal cost -.005MCr*605=-3.025MCr errata for pp.65."
line should read: "Coatings bare metal cost -.00005MCr*605=-.03025MCr errata for pp.65." add 2.99475MCr to ship cost.
Cost 43.45MCr now 46.445MCr
Budget 12MCr down payment 8.6888MCr remaining 3.3112 MCr now 9.28895MCr remaining 2.711MCr)

Remaining hull volume 311.3991m3
Maneuver fuel 308m3 22mt
ship's locker 3.4m3
loaded Mass 242.69mt 18900kN 7.788g 23.625m3/hr tankage supports 13 hours.
remaining uncomitted area 163.202m2
Cost 10.08805MCr down payment 2.0176112MCr
payment .08406MCr for 240 months.
budget remaining .6933888MCr
 
That leaves the TL15 build of the 300DT cargo pod budget is .6933888MCr
Specifications needed to meet:
two grapels 1st one is for a 100DT sphere unstreamlined needs plumbing for jump fuel and power transfer while pumping for jump.
2nd one is for a 100DT short cone with airframe also needing fuel and power transfer while pumping for jump
Nice to have power plant and a small HePLAR with maneuver fuel reserve.
Build hull first see if we have budget for the HePLAR.
Hull sphere unstreamlined 5400m3
Hull material superdense armor 20 toughness 20 1 cm thick 20m diameter area is 1259m2 structure factor is 1.21 stressed to 1g
Hull material = .001m*1259m2=1.259m3 mass is 18.885mt .017626MCr no power needed.
internal structure 1.21m3 18.1mt .01694MCr
Hull coating colored discount -.06295MCr
Grapel for 100DT sphere unstreamlined 19.321m3 19.321mt .019321MCr full services grapel.
Grapel for 100DT cone airframe 96.605m3 96.605mt .057963MCr Full services grapel
pass through piping with cutoff valves for fuels and power in 100MW range
14m3 2mt .001MCr
14 large cargo doors -280m2 .28MCr
No electronics, or controls except for mechanical ones for the doors. No heat, interior lighting by material handling equipment from the starport.
No computers no automation.
Internal cargo 4998m3 (357DT) 49980mt max load 3570mt average load cargo efficiency 357m3/cargo hatch
internal fuel tanks 385m3 27.5mt
empty mass 154.911mt average load 3,752mt max load 50,162mt
Cost .356589MCr
Buy cargo pod outright
remaining budget .3368MCr
 
OK there you have it, all three designs specified.
Cargo pod holds 357DT cargo with reserve fuel tankage 27.5DT costs about 356 thousand creditsand pays for itself with one carrying contract
the drop tank craft has 50DT jump fuel and 22DT of maneuver, fuel skims fuel in 1 hour purifies 50DT jump fuel in 1 day has life support for 24 hours pulls 7.7g for 13 hours cost is a bit more than 10MCr provides 98MW through the cargo pod to pump for jump. Cost 10.08MCr payment .08406MCr
Main ship can dock with the cargo pod and perform J1 with the entire 500DT can also do a J1 using a 11 DT drop tank and retain the drop tank.
Carries 80DT of internal cargo 2 large cargo doors 560m3 of cargo per door or about 50% efficiency. Cost 46.445MCr payment .33175MCr
budget:
.3368MCr
-.33175MCr
-.08406MCr
have to make .07901 in a month the first month.
As all three of these were ordered from Glisten and the 300DT cargo pod has literally no electronics or power systems it should be possible to have all three ready for delivery the same day or close to it, especially if I tell them that this is for a project the duke is funding to increase trade between Glisten and Aki. :) see my sig.

First trip I have had 10 months to line up cargos between two HI IN worlds.
Pod 357 DT general cargo no heat or lights provided must be containerized.
Main ship 80DT grav comped and life supported cargo
Expendables 50DT maneuver fuel, 50DT jump fuel, two weeks food at 72CR/day
Crew: Owner aboard: Pilot 2 navigator 2, engineer 2 vacc suit 2. big craft pilot: pilot 2 coms 1 vacc suit 1 mechanic 1 EVA trained (0)
Note: Drop tank craft provides refined fuel, and consumes most of it's maneuver fuel pushing the assy to jump point so purchasing 28.5DT of unrefined fuel and the meals at the high port.
baseline revenues 437DT cargo at 1000C/DT= MCr.437 per jump, 3 jumps per month is the goal, but depends on cargo mass. I can make my ship's payments and crew pay with just 1 jump a month carying other peoples stuff. Should be able to purchase the other two cargo pods in a couple of months and hire brokers when the pods are ready.
 
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