The DD Harriman

[Drakon]

Got around to writing up this ship up for a game I am playing. The writeup is done using Brilliant Lances.

The Harriman is owned by Gilbert Buchanan, a retired free trader and founder of Buchanan Star Lines of Terra.

Delos David Harriman (GS 771907)
General Data:

Displacement 200 Dtons; Hull Armour: 28
Length: Volume: 2,800 m3
Price: 82.38 MCr Target Size: S
Configuration: Wedge/ SL Tech Level 14 (TL 12 electronics)
Mass: empty/full 1058.4/2442. tonnes

Engineering Data:

Power Plant 250 MW fusion power plant (XX.X MW per hit) I year duration (24.7075 MW shortfall)
Jump Performance: 2 (420m3 fuel)
G Rating: 2 G (200MW), Contra-Grav lifters (20 MW)
G-turns: (20, 36.8 turns with Jump Fuel)
Maintenance: 110 points

Electronics: (TL 12)

Computers: 3-TL 12 Model, 2 Standard and 1 FIB, (1.6MW total)
Commo: 30,000km radio (1 hex; 1 MW), 1 OOOAU maser (-; 0.6 MW)
Avionics: TL 12

Sensors:
Passive EMS fixed array 30,000km (1 hex; 0.03 MW)
Active EMS: 300km(O hexes; use extreme range for task difficulty in same hex 5 MW)

Controls: Flight Deck with 5 Workstations, plus 2 other workstations

Armament: 2 turret hardpoint sockets fitted (Loc: 16/1 7, 18/19; Arcs: All)
2-150Mj lasers

Accommodations:
Life Support Extended (0.56 MW), Gravitic Compensators (1G; 14 MW)
Crew 6 (2x Maneuver, lx Electronics, 2xEnginneering, lx Steward)
Crew Accommodations: 5xSmall Stateroom (0.0005 MW ea.)
Passenger Accommodations: 6xSmail Stateroom (0.0005 MW ea.)
Air Lock 2
Cargo: 679.6 m3

Notes: The Harriman is a 200 ton starship owned by Gilbert Buchanan, of Terra. (SR 1827)

Constructed at the Drakonian Aerospace Shipyards, Burroughs, Terra IV (Mars) (SR1827) in 1114, she is a TL 14 (with TL 12 electronics) A-BS22, Beowulf/Moraine style star ship. With everything on, including M drive, and weapons, the ship consumes 274.7 MWs meaning that it cannot operate them all at once with its 250 MW plant. Lifters are not needed once away from a planet, so those are shut down.
Fuel Purification machinery (0.9 MW), 7.667 hours to refine 720 m3 (65.7 tons)

So what do you think?

 

[AnotherDilbert]

Initial reaction:

Very little manoeuvre fuel. Why bother with 2 g drive when you only have fuel for an hour or two?

5 staterooms for 6 crew is a bit petty?

Woeful sensors. Why bother with turrets if you can't see the enemy?

Turrets, but no gunners?

An MFD or two would be a trivial cost, but make the turrets significantly more effective.



I get something like this:
200 Dt, MCr 72, 1250 m³ cargo (added MFD)

Notes:

Your ship is a bit undercrewed? Needs a commander and gunners?

I believe we disagree about how to calculate manoeuvre fuel?
The lack of manoeuvre fuel makes it very slow, and is a severe problem if the target star system (or possibly even the target world) has a different velocity vector than the origin system.

You could save almost 10% of the ship's cost by using 1 g drive?

We must be calculating something differently, since I get much more cargo space than you, but we both get the same loaded mass?

I would want better sensors; ~4 hexes should be affordable. If the environment is dangerous enough that we need a significant investment in turrets, we need to see the dangers.



I might prefer something like this:
200 Dt, J-2, M-1, 12 small staterooms (single occupancy), 1000 m³ cargo, MCr 71.
1 g drive, with 40 Gturns of fuel.
Much better sensors and radio. (OK, I might have gone overboard a bit with the sensors.)
Still lacking a bit of power, so can only use power hogging radio and AEMS when drives are offline.

 

[Drakon]

1) One thing that confused me was that originally, the Beowulf needed a crew of 4. Going to Brilliant Lances the full crew swells to 6 (or 7). The difference between a Moraine and a Beowulf, which is supposed to be the TNE version of the Beowulf, has me a bit confused. I realize there are differences in the design systems but the changes seem a bit radical.

2) Maneuvering fuel: There are 10 hours worth of maneuvering fuel at 2 Gs aboard the Harriman, as compared 28 hours at 1 G on the Moraine. (20 turns versus 56) Yes, this means less duration for a full burn. I have not done the calculations for a 1 G burn. Because you have 2 Gs available does not mean you have to burn at 2 Gs throughout

3) We have extremely different cargo space volumes. Yours is almost double. This discrepancy is probably why maneuvering fuel is low (as well as staterooms)

4) Sensors, and comms are the same as the Moraine, except upgraded from TL 10 to TL 12. Computers were upgraded as far as TL (from 10 to 12) and one of the Moraine's 3 computers was also upgraded to a FIB.

5) I see her as more of a freighter than a warship. She has some defensive capability but her primary mission is hauling cargo, not fighting.

Thank you for your input. This is a big reason I posted it here was to get just this kind of feedback. We may differ on a few issues, but your feedback is appreciated. Thanks

 

[Drakon]

Original Moraine writeup from Brilliant Lances, for comparision

Moraine/Beowulf Class Freighter:

General Data
Displacement: 200 tons Hull Armor: 10
Length: 43 meters Volume: 2800m3
Price: MCr46.47 Target Size: S
Configuration: Wedge SL Tech Level: 10
Mass (Loaded/Empty): 1908.146/1074.746

Engineering Data
Power Plant: 156MW Fusion Power Plant (52 MW/hit), 1 year duration (17.967 MW power shortfall)
Jump Performance: 1 (280 m3fuel)
G-Rating: 1G (100 MWJG), Contra-Crav lifters (40 MW)
G-Turns: 56 (78.4 using jump fuel), 12.5 m' fuel each
Maint: 89,

Electronics:
Computer: 3xTL-10 Model St (0.3 MW ea.)
Commo: 30,000km radio (1 hex; 1 MW), 1 OOOAU maser (-; 0.6 MW)
Avionics: TL-1O+ Avionics

Sensors:
Passive EMS fixed array 30,000km (1 hex; 0.06 MW).
Active EMS 300km(O hexes; use extreme range for task difficulty in same hex 15 MW)

Controls: Flight deck with 3xWorkstation, plus 2 other workstations

Armament: 2 turret hardpoint sockets fitted (Loc: 16/1 7, 18/19; Arcs: All)

Accommodations:
Life Support Extended (0.56 MW), Gravitic Compensators (1G; 14 MW)
Crew 6 (2x Maneuver, lx Electronics, 2xEnginneering, lx Steward)
Crew Accommodations: 6xSmall Stateroom (0.0005 MW ea.)
Passenger Accommodations: 8xSmail Stateroom (0.0005 MWea.)
8xLow Berth (0.001 MW ea.)
Cargo: 764.8 m^3: 2 large cargo hatches
Air Lock 2
Notes
The Moraine is the TL-10 version of the more popular and useful Beowulf class. The Moraine's systems consume 174 MW of power, meaning that it cannot operate them all at once with its 156 MW plant. In space, the contragrav drive is shut down to conserve power. When taking off from a planet, the Moraine cannot power its G-Compensators, and thus ail crew and passengers must be strapped in for this evolution.
Fuel Purification machinery (1.53 MW), 30.8 hours to refine 980 m3 (70 tons)

 

[whartung]

I agree on the fuel. 20 G Turns on a 2G ship, resulting in 10 full burn maneuvers, I think is simply too small, especially for a combat vessel. Particularly for a patrol vessel.

There's no reason to not leverage jump fuel for an in-system patrol ship, theorizing that when it does, indeed, come time to jump, you just top off an go.

But that's a different aspect for an assault or intruder role where the expectation is full boat combat on exit, at which point your jump fuel is not available for maneuver.

So if the ships role is more for picket duty, then by all means leverage the jump fuel space for maneuver.

 

[Drakon]

I agree on the fuel. 20 G Turns on a 2G ship, resulting in 10 full burn maneuvers, I think is simply too small, especially for a combat vessel. Particularly for a patrol vessel.

The Harriman is a freighter, not a patrol or combat vessel.

 

[Drakon]

AnotherDilbert: I like your numbers better, and hope that you are right and I screwed up the math. If 20 Gturns is 250m3, and cargo is 1250, that solves my issue immensely. I can add another 250m3, or possibly more and still have plenty of cargo space to be viable.

 

[Timerover51]

I assume that the power requirements for your electronics and life support are set by the rules, but they seem to be quite excessive, except for the power requirement for the small staterooms and low berths, which seem to be too low.

Electronics:
Computer: 3xTL-10 Model St (0.3 MW ea.)
Commo: 30,000km radio (1 hex; 1 MW), 1 OOOAU maser (-; 0.6 MW)
Avionics: TL-1O+ Avionics

Sensors:
Passive EMS fixed array 30,000km (1 hex; 0.06 MW).
Active EMS 300km(O hexes; use extreme range for task difficulty in same hex 15 MW)

Three hundred kilowatts per computer for the computers? I would argue for more like a kilowatt apiece. The megawatt for commo and 15 MW for active EMS seem off be a factor of at least 10 on the high side. As for the maser, that would be its peak output when used, not a continuous power drain. It would also make a good weapon to burn out active and passive microwave sensor arrays.

Accommodations:
Life Support Extended (0.56 MW), Gravitic Compensators (1G; 14 MW)
Crew 6 (2x Maneuver, lx Electronics, 2xEnginneering, lx Steward)
Crew Accommodations: 6xSmall Stateroom (0.0005 MW ea.)
Passenger Accommodations: 8xSmail Stateroom (0.0005 MWea.)
8xLow Berth (0.001 MW ea.)

Five hundred and sixty kilowatts for life support? What precisely are you powering? You have water recycling, atmosphere monitoring, CO2 scrubbing, and oxygen renewal along with food preparation and refrigeration. How is that going to take 560 kilowatts? Five kilowatts sounds a lot more reasonable.

With respect to the staterooms, 50 watts apiece seems to be excessively low. You have to light them and maintain a reasonable temperature in them. A budget of 500 watts seems more appropriate.

As for the low berths, one kilowatt strikes me as too low, assuming that the low berths maintain a much lower body temperature, which means refrigeration along with sensor monitoring. You might make it work, but I would tend to be more conservative and go with somewhere between 5 and 10 kilowatts.

Again, I assume that the power requirements are set by the rules, but as I see it, rules are guidelines, and if they seem wrong, change them.

 

[AnotherDilbert]

Jump Performance: 2 (420m3 fuel)
G-turns: (20, 36.8 turns with Jump Fuel)
...
2) Maneuvering fuel: There are 10 hours worth of maneuvering fuel at 2 Gs aboard the Harriman, ...

I suspect that you have included 40 Gturns = 500 m³ of manoeuvre fuel. That would go some way towards explaining the difference in cargo space.

420 m³ jump fuel is 420 / 12.5 = 33.6 Gturns, double the 16.8 you used above.

Note that 1 Gturn for a 200 Dt ship is 12.5 m³, as you have noted in the Beowulf stats.


1 Gturn is 1 g for 1 turn (half hour), 2 g for 1 turn is 2 Gturns, 2 g for 2 turns (1 hour) is 4 Gturns.

20 Gturns is 2 g for 10 turns = 5 hours. 2 g for 10 hours = 20 turns is 40 Gturns.


This would make your design something like this:

Note that I have used TL14 equipment, except for the computers.

Required crew is highly dependent on the computer and Cp. You could use cheaper computers, but probably at a cost of more required crew.

 

[AnotherDilbert]

The megawatt for commo and 15 MW for active EMS seem off be a factor of at least 10 on the high side.

The power requirements for radars and radios increases exponentially with range. I would call a high resolution radar with 240 000 km range for only 13 MW a bargain, and count myself lucky.

 

[Drakon]

so, 40 G turns at 2G, is 20 turns or 10 hours so.. back to where I started from.

The electronics were set to TL 12, partly because it was pointed out that it is harder for the local star ports to repair much higher.


Let me think about it

 

[Drakon]

One thing that occurs to me, is that having 40 G turns of fuel should be sufficient, I can't run 2 G full burn for long, but I can run 1 G for sufficient time to do most of the things a freighter may need to do. Having overpowered engines means short bursts at higher acceleration.

It's more a manner of use,

 

[AnotherDilbert]

One thing that occurs to me, is that having 40 G turns of fuel should be sufficient, I can't run 2 G full burn for long, but I can run 1 G for sufficient time to do most of the things a freighter may need to do.

Sure you can have 2 g drives, it's your ship.

But it costs MCr ~7 and about 7 Dt cargo, yet the ship will not be faster, it will just attain top speed a little sooner.



I just used TL14 commo&sensors because my spreadsheet automatically use the Ship's TL for such equipment. The difference is not great.

 

[whartung]

One thing that occurs to me, is that having 40 G turns of fuel should be sufficient, I can't run 2 G full burn for long, but I can run 1 G for sufficient time to do most of the things a freighter may need to do. Having overpowered engines means short bursts at higher acceleration.

It's more a manner of use,

You don't need the G Turns for acceleration per se. You can get up to a pretty good clip with a few G turns of burn. And most routine acceleration is to get you to the planet and/or 100D.

Rather, particularly for a combat ship, it's the turning and course corrections that burn up the fuel.

Simply, you need as much fuel, and ideally more fuel than, the ships you fight. Because once you hit zero -- you're out (or very soon will be) of the fight.

 

[Drakon]

Simply, you need as much fuel, and ideally more fuel than, the ships you fight. Because once you hit zero -- you're out (or very soon will be) of the fight.

Very good point. Against another 1 G ship, the faster drive will win, with short sprints. For a freighter, it seems to me all about getting to the jump point first. Even by just a little bit.

 

[Drakon]

I am missing something here,

Power Plant 250 MW fusion power plant (XX.X MW per hit) I year duration (24.7075 MW shortfall)

Where do I find the per hit reductions? I looked through Brilliant Lances and am just not seeing it. Old eyes

 

[AnotherDilbert]

All components take 1 major hit for every 100 tonne mass.

A TL-14 fusion power plant of 250 MW has a mass of 250 tonnes, so takes 3 major hits, so 250 / 3 = 83 MW per hit.


Edit: Technical Booklet, p17, "Evaluate System Damage".

 

[Drakon]

All components take 1 major hit for every 100 tonne mass.

A TL-14 fusion power plant of 250 MW has a mass of 250 tonnes, so takes 3 major hits, so 250 / 3 = 83 MW per hit.


Edit: Technical Booklet, p17, "Evaluate System Damage".

Yep there it is, thank you very much. Thank everyone for all their efforts and apologies for my bad eyes and math.