Ship Design Philosophy

Discuss the Traveller RPG and its many settings
baithammer
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Re: Ship Design Philosophy

Postby baithammer » Tue Feb 20, 2018 11:53 pm

There is no such rule in the new edition. Do we apply all the rules from first edition to second edition - or just cherry pick?
Its called inferred from examples provided where no capital ship in the new system has a thrust value over thrust 6, that isn't a cherry pick its what has been presented. You also keep bringing past editions up in discussions so I backed up precedence from the earlier edition.
You have no medium to exchange energy with. As a result ships in space can not bank and turn like aircraft, nor can the suddenly stop and reverse direction - handbrake turn.
Dogfighting is getting into range where a missile exchange would be less than ideal and where maneuver is more important than speed, which doesn't limit itself to a particular medium.

As for banks and turns, a spacecraft can certainly simulate banks and turns but would be rather wasteful given the environment they operate under.

Stop and reversing direction in a spacecraft is rather easy in space unlike air.
Sigtrygg
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Re: Ship Design Philosophy

Postby Sigtrygg » Wed Feb 21, 2018 12:11 am

To stop and reverse direction you have to completely cancel your current vector.
A space fighter moving at 75km/s 'north' has to apply enough thrust to cancel that before it can move south. You can't just blast across space building up a thrust related vector as you go and suddenly have no vector relative to your target - not physically possible.

Play Triplanetary or Mayday to learn about vector/Newtonian movement
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Re: Ship Design Philosophy

Postby AnotherDilbert » Wed Feb 21, 2018 12:43 am

Sigtrygg wrote: Dogfighting in space under Newtonian physics with 6g+ drives is preposterous, ...
Of course.

I guess the dogfight rule was added to make fighters viable in space combat, which was rather successful, since many people like fighters.

If you do not like it simply remove the dogfight rule and fighters will cease to be a problem...
baithammer
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Re: Ship Design Philosophy

Postby baithammer » Wed Feb 21, 2018 7:47 pm

Sigtrygg wrote:
Wed Feb 21, 2018 12:11 am
To stop and reverse direction you have to completely cancel your current vector.
A space fighter moving at 75km/s 'north' has to apply enough thrust to cancel that before it can move south. You can't just blast across space building up a thrust related vector as you go and suddenly have no vector relative to your target - not physically possible.

Play Triplanetary or Mayday to learn about vector/Newtonian movement
Outside of transit you wouldn't want that amount of speed and would start reserving some of your thrust in order to maneuver.
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Re: Ship Design Philosophy

Postby SSWarlock » Thu Feb 22, 2018 3:42 pm

Sigtrygg wrote:
Wed Feb 21, 2018 12:11 am
To stop and reverse direction you have to completely cancel your current vector.
A space fighter moving at 75km/s 'north' has to apply enough thrust to cancel that before it can move south. You can't just blast across space building up a thrust related vector as you go and suddenly have no vector relative to your target - not physically possible.

Play Triplanetary or Mayday to learn about vector/Newtonian movement
Better yet, play "Elite Dangerous" using fixed weapons and turn off the Flight Assist setting while in ship-to-ship combat. Not perfect but a decent intro to Newtonian physics.
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baithammer
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Re: Ship Design Philosophy

Postby baithammer » Thu Feb 22, 2018 4:56 pm

Funny you should mention Elite and Dangerous as I've had that game for awhile.

It also follows the point about differing speeds.

1.) Has maneuver speed, in combat you can slow down to dedicate more thrust to agility.
2.) Transit speed which handles movement in system.
3.) Has a jump mechanic.
SSWarlock
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Re: Ship Design Philosophy

Postby SSWarlock » Fri Feb 23, 2018 1:08 am

baithammer wrote:
Thu Feb 22, 2018 4:56 pm
Funny you should mention Elite and Dangerous as I've had that game for awhile.
Heh. I made my last post while my ship was supercruising across the Alpha Centauri system to a starbase at Proxima Centauri. I truly hate that star system; takes freakin' forever to cross it.

Elite dangerous is a pretty decent Travelleresque MMORPG. Using a Voice Pack with the VoiceAttack voice control system is fun when I get to say "Engage the jump drive!" LOL
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Re: Ship Design Philosophy

Postby Condottiere » Fri Feb 23, 2018 7:07 pm

Condottiere wrote:
Tue Feb 20, 2018 4:45 am
Starship: Cutlass Class Commercial Cruiser

This would be a combination of the Broadsword with one of it's cutters.

A two hundred tonne hull, with a performance of three gees and three parsecs, with a payload of a thirty man platoon, one air/raft, and two all terrain vehicles.

With the engineering compartment limited to thirty five tonnes, the basic crew would be a pilot, a navigator and an engineer, with two gunner positions.

Electronics would be a ten tonne bridge and military sensors.

Engineering would allocate twenty tonnes to a jump drive, six tonnes to a manoeuvre drive, and nine tonnes to a power plant.

Sixty one tonnes of fuel, enough for thirty one plus days of operations, and a three parsec drop down the rabbit hole.

. Hull
.. two hundred tonnes
.. streamlined
..... twelve megacredits
.. armour
... crystaliron
... factor four
... ten tonnes
...... two point four megacredits
. Engineering
.. thirty five tonne compartment
.. propulsion
... manoeuvre drive
.... thrust factor three
.... six tonnes
...... twelve megacredits
.. hyper transition
... jump drive
.... three parsec range
.... twenty tonnes
...... thirty megacredits
.. power plant
... fusion
.... one hundred thirty five scotts
.... nine tonnes
...... nine megacredits
. Bunkerage
.. sixty one tonnes
... three parsec range
... thirty one plus days operations
.. fuel scoops
.. fuel processing
... twenty tonnes per day
... one tonne
...... fifty kilocredits
. Electronics
.. bridge
... ten tonnes
...... one megacredits
.. computer
... twenty bandwidth
... fibre
...... seven point five megacredits
.. sensors
... military
.... two tonnes
...... four point one megacredits
. Armament
.. turret
... triple
... beam lasers
... thirteen scotts
...... two point five megacredits
.. turret
... triple
... missile
... one scott
...... three point two five megacredits
. Defences
.. none
. Systems
.. repair drones
... two tonnes
...... four hundred kilocredits
. Accommodations
.. staterooms
... standard
.... fifty tonnes
...... megacredits
.. barracks
...
...... megacredits
.. low berths
...
...... megacredits
.. common areas
... none
.. armory
... hour tonnes
. Cargo
.. vehicle allocation
... all terrain vehicle
.... two
.... twenty tonnes
...... three hundred ten kilocredits
... air/raft
.... one
.... four tonnes
...... quarter megacredits
. Software
.. Jump Control
... three
... fifteen bandwidth
...... three hundred kilocredits
.. Library
.. Manoeuvre
.. Auto Repair
... two
...... ten megacredits
.. Evade
... one
... ten bandwidth
...... one megacredits
.. Fire Control
... one
... five bandwidth
...... two megacredits
. Crew
.. pilot
.. navigator
.. engineer
. Operating costs
.. maintenance
...... per month
. Purchase cost
......98.66megacredits
. Power requirements
.. manoeuvre drive
... sixty scotts
.. jump drive
... sixty scotts
.. basic ship systems
... forty scotts
.. sensors
... one scott

preliminary
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Re: Ship Design Philosophy

Postby Condottiere » Sat Feb 24, 2018 3:30 am

Starship: Cutlass Class Commercial Cruiser

Scaling downwards requires compromises, since some items are just fixed volumes.

Personally, I doubt that the iconic Broadsword is fit for stated purpose in Mongosian space (or Mongooseverse?).

I'm looking at purchase price of about a third of the Broadsword, with a quarter of the firepower and no smallcraft. In theory, you could patrol with the Cutlass, but you aren't likely to catch up with most commercial traffic, and a pirate is likely to be able to outgun you, probably outrun you as well.

Armament mix is divided between a laser and a missile battery, allowing the Cutlass to provide ground support.

If it acted as a straight out dropship, you could retain the spherical configuration, but I thought a neat twist would be to take a standard template, hollow it out and it really does become a commercial cruiser (and possibly a Q ship).

Image

The hull could be built in any technological level ten shipyard, assuming you keep the armour; you could in fact half the armour.

And if you aren't chasing anything, or tagging along as convoy protection, you probably don't need a three parsec range range.

Using a commercial model allows more discretion and easier infiltration; making it streamlined, allows landing at covert locations.
baithammer
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Re: Ship Design Philosophy

Postby baithammer » Sat Feb 24, 2018 7:31 am

Tl12 is typical commercial hull and TL10 has way too many limits.

- TL 10 limits you to jump 1
- Don't see any missiles listed ( Unless your limiting to only what the rack can hold)
- Barracks take up 2dt per person
- Don't see an Armoury

Here's a different take on the same setup.

Image

Replace the Comp 35 /bis with Core 40 as the former is TL15.
Condottiere
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Re: Ship Design Philosophy

Postby Condottiere » Sat Feb 24, 2018 7:24 pm

They're default values, rather than optimized ones. I don't think there's a spare kilogramme. I'm sort of feeling my way here.

I allocated four tonnes to the armoury, that would support either twenty marines or eighty crewmembers, not that I think it would be interchangeable.

What it really comes down to is how large a party is or should be feasible. Sure, the Sulaco is huge, but in the end you have a squad of twelve Marines, one android, one supercargo, and one adviser.

You could also crowd in personnel, though that's likely to effect morale over the long term.

A troop transport doesn't have to be fast, nor well armed or protected, just convoyed; the Broadsword is not a troop transport, and I don't think it qualifies as a commando and/or assault platform either.

As for the hull, in theory, sourcing the hull from a lower technologically based spaceyard should be cheaper, if you bear in mind that the default factor zero armoured hull can be technological level seven titanium steel, since it makes no difference in protection, price or performance; nine if you want artificial gravity, and ten for crystalironed on armour plating, since I don't recall any ship having armour factor greater than ten using it.

It should also make hull repair cheaper and easier.

The engines can be manufactured at a higher technological levelled facility.
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Re: Ship Design Philosophy

Postby Sigtrygg » Sat Feb 24, 2018 7:53 pm

A long time ago Games Workshop produced a book of ships called the IISS Ship Files for Traveller. In there you will find the Iylvir class IN Light Assault Troop Carrier designed to carry a 28 man marine platoon.
Jump2, m2, 2 turrets, factor 9 hull armour, 28 marines, 4 g-carriers and equipment or 72t cargo.

War surplus versions may make it into private hands post FFW...
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Re: Ship Design Philosophy

Postby Condottiere » Sat Feb 24, 2018 9:54 pm

I'm working with existing templates, and while I don't mind breaking them, I'd like to know what I'm breaking, so I can rationalize it.

A two parsec range looks reasonable for a low end troop transport, though one by it's lonesome needs protection or the means to avoid combat; thrust factor two is likely the legacy of power plant factor two, much like thrust factor three for the Broadsword is the legacy of power plant factor three.

Another issue is crewing.

I tend to craft engine sizes to conform with engineer requirements precisely; so, at what tonnage is it a requirement for a spaceship to have an engineer on tap? The scoutship can get away with not having one.

For the mercenary aspect, once negotiations are concluded, how fast would an employer expect their new troops to be deployed? Two parsecs per jump with commercial transport seems about right, whereas having their own duojump ships seems the same speed, the difference is that they don't need to hire or buy passage on commercial shipping, so removing most unexpected, or expected, delays.

Equipment is less likely to be damaged, or subject to inspection by third parties; I'm not sure why they would bother shipping All Terrain Vehicles interstellar distances, except that there are no Toyora pickups at destination.
baithammer
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Re: Ship Design Philosophy

Postby baithammer » Sun Feb 25, 2018 2:00 am

The 2 parsec jump requires TL11 minimum and the general tech level for commercial ships is TL12, so going TL10 isn't really advantageous.

Thrust 2 and Jump 2 is reasonable for a transport but with it not having an auxiliary to handle landings needs its own defenses. ( Also benefits from higher thrust /jump )

As to engineers, if the craft is going to operate more than 24 hrs at a time than an engineer should be on board but this doesn't mean you need a separate assignment. For example, you can have someone with both the mechanics /engineering skill covering both roles.

Having ones own atvs is useful to have when not on contract and having to move to better employment areas.
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Re: Ship Design Philosophy

Postby Condottiere » Sun Feb 25, 2018 7:32 pm

I think you may be missing that assembly is not necessarily the same as construction.

Your phone case doesn't necessarily need the same technological finesse to manufacture as the embedded CPU. The hull could be prefabricated, and individual more advanced shipyards could purchase them, and just concentrate on the internal components.

Technological ten hulls would seem ideal as the default commercial platforms, having artificial gravity and a frame which to attach crystaliron armour plating. Any technological level yen shipyard can then fairly easily repair them.

As for onboard terrestrial transport for mercenaries that you schlep across interstellar distances, the air/raft may be ideal.

They are more flexible than an all terrain vehicle, and I suspect you could stuff them together tighter in the cargo hold.
baithammer
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Re: Ship Design Philosophy

Postby baithammer » Sun Feb 25, 2018 8:33 pm

Notice how there is very few designs at TL10 compared to TL12 and how the trader designs as well as the scout are TL12?
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Re: Ship Design Philosophy

Postby Condottiere » Sun Feb 25, 2018 11:08 pm

You can only speculate, though I'd say part of it was that technological level twelve is recognized as a mature interstellar civilization.

The stated technological level of construction would be more of a cap on how advanced the components available are to the shipyard.

What's the minimum technological level requirement for a bridge? There's a great deal of difference between an Apollo capsule and the Enterprise of the Kelvinverse. Going by High Guard, technological level seven suffices. Technological level nine introduces holographic controls, but isn't a requirement for high technology manufactured spaceships.

Another reason to use technological level twelve is access to fusion power plants, that are fifty percent more powerful than early fusion, available at technological level eight.
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Re: Ship Design Philosophy

Postby baithammer » Sun Feb 25, 2018 11:41 pm

The number of designs listed as standard all center on TL12, which infers that the most common shipyard is TL12 otherwise standard designs would be set at whatever the common tech level would be. Would be more effective to buy a used TL12 ship then buy a new TL10 one.
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Re: Ship Design Philosophy

Postby Condottiere » Mon Feb 26, 2018 12:36 am

It's quite possible that most spaceyards are all tooled at technological level twelve, like I think starports probably are.

However, new tooling tends to cost money, and in a lot of cases, electronic companies tend to build new factories to incorporate them, while maintaining the older ones that are specced to older manufacturing processes that then cater to clients and products that don't need cutting edge technology.

There is no stated benefit in building a hull, especially an unarmoured one, higher than default of the stated requirement, as compared to engineering and weapon systems that can be tweaked to take advantage of a higher technological level manufacturing processes.
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Re: Ship Design Philosophy

Postby baithammer » Mon Feb 26, 2018 2:54 am

On the same argument, there is no advantage to building at lower than common TL either. Given that security forces are generally TL13 with the military being at TL15 the tooling costs wouldn't be an issue and appear to have been at TL12 for a significant period of time.

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