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Wiki Discussion: Ship Mission Codes

This gave me the idea of a general classification code that overlays the T5 mission codes. Many of them are obviously related. Perhaps taking a pass over the table can smallify the list as a General Ubercode System-Thing.

I'll highlight the bits that are different from your table.

I've got 15 codes. Can't say it doesn't hurt a little bit.
I've been trying to work this from the top level down. Starting from the Service code (Navy, commercial, non-commercial), and applying the Type code. I end up with 12 codes (navy fleet, navy independent, navy defense, navy auxiliary, commercial trader, commercial freighter, commercial liner, commercial resource, commercial general, non-comm lab, non-comm scout. non-comm private). However there are some overlap codes.

For example The naval service needs troop transports, which I've stuck into the commercial liner group. The non-comm needs a well armed (Naval Auxiliary / Fleet style) ship. Can these use the same codes because they are (essentially) the same design? Or should the be separate codes?

My brain very much want to force the design === primary mission code. If two (apparently different) ships end up with almost identical designs from a build point of view they should end up with the same primary mission code.
 
Thomas, let me come at it from another angle.



This gave me the idea of a general classification code that overlays the T5 mission codes. Many of them are obviously related. Perhaps taking a pass over the table can smallify the list as a General Ubercode System-Thing.

I'll highlight the bits that are different from your table.

I've got 15 codes. Can't say it doesn't hurt a little bit.


NOTES
I dropped the "Z" -- not because it's not cool, but because it is so seldom used.
I defer "Carrier"/"Tender" to secondary modifier code(s).

It hurts to paper over some of these codes; calling it an "overlay" takes a lot of the sting away.




(T5 B2 p68)

"Category D/E" Mission Code
(WIKI PROPOSAL)

"Category C" Mission Code
DescriptionExamples
T - Transport
A - Trader
U - Packet
A - TraderGeneral purpose mixed mode trade and passenger carriers. Designed for independent and unscheduled operation for opening new markets.free trader, orbital or far port, packet, cargoliner
C - Cruiser
G - Frigate
T - Assault
H - Ortillery
B - Battle


C - Cruiser
(B) Primary combat ships designed for task forces or fleet supporting each other.

(C) Combat ship designed for independent operation and mobility operating alone or in small groups.
battleship, dreadnought, assault, ortillery


cruiser, frigate, intruder
S - Sentinel
D - Defender
B - Boat
N - Monitor
D - Defense
Ship for defending assets like worlds, bases, and supply lines.

System Defense Boat, monitor, sentinel, picket, orbital fortress
V - Destroyer
E - Escort
T - Aux Navy Transport
W - Barge
T - Tender/Tug
P - Picket
P - Patrol
E - EscortArmed ship to support military operations other than the previous groups.Escort; mine-layers/sweepers gunships, customs enforcement, patrol, destroyer, corvette, sloop
J - ProspectorJ - Mining & SalvageShips to gather and process resources.gas giant skimmer, mining, prospector, salvage, refinery
K - Safari
K - Expedition
K - ExpeditionLong duration private chartered ship for recreation and tourism.safari ship, personal touring ship
L - Lab
N - Med
N - Survey
B - Beagle
L - LaboratoryResearch vessels. Detailed survey vessels.Sensor platforms, lab ship, Beagle, Survey
M - Liner
N - Med
M - LinerShips designed to transport people as comfortably as possible. Commercial are on scheduled routes.subsidized liner, clipper, megacorporate long liners and transports
P - Corsair
R - Raider
P - Marauder
P - Privateer
P - CorsairAnti-logistics ships designed to harm commercial traffic and supply auxiliaries.corsairs, raiders, marauders, privateers.
Q - Small CraftQ - Small CraftA catchall category for all small craft.Lifepod, fighter, gig, launch, ship's boat, pinnace, cutter, shuttle, drone
R - Merchant
F - Freighter
R - MerchantShips for primarily or exclusively carrying freight.bulk cargo, freighter, container cargo, subsidized merchant
S - Courier
S - Messenger
S - Scout
X - Express
S - Recon/CourierLong duration, independent scouting missions, for gathering intelligence beyond state borders and transmitting messages inside state bordersscout, explorer, military spy, diplomatic, first contact, system surveillance, express, search / rescue ships
T - Transport
T - Tug
W - Barge
T - General TransportA catchall category for commercial/non-commercial ships not covered by other codes.Mobile repair facility, tugs, barges, agricultural ships, factories, tenders.

Tanker, military resupply, military ordinance, transport, prison, medical, troop transport, colony ship.
Y - YachtY - LuxuryShort duration privately owned and operated luxury leisure ship.yacht, corporate packet ("business jet"), diplomat transport, head-of-state transport
Specific issues I have with this suggestion, which I like, but still have concerns.

The codes I select for the wiki table version are based upon previous canon, but I'm not married to them. If it makes the process work better to select one of the T5 letter codes for a given row, and this makes the wiki as strict subset of the T5 definitions I approve of that.

The Cruisers and Corsairs should be combined into the same group. They're both mobile independent operations ships. This way you also get things like the 800-ton mercenary cruiser and 1200 ton frontier cruiser. And the Privateers. All of which are very close in design.

The Barge, Tender/Tug are not armed and should not be in the E - Escorts group. But see previous message about military/non-comm splits. This also affect the picket/patrols ships as armed non-comm ships.

I'm not as as enthusiastic about keeping the K - Expedition ships and specific designs could be tossed into either the L or Y groups depending upon design.

I'd been putting the small craft under their appropriate working group (e.g. Trader, Transport, Navy Auxiliary) rather than having a separate primary code. Purpose trumps size. In properly defining ACS/BCS/FCS/WCS adding a QCS (Small class ship) for size up to about 200 tons but no jump drive for in-system work may be a thing.

As an aside: I've been trying to push for a single set of primary mission codes. You have stated there may be different codes for the different size classes. The ACS and BCS ships may have a different set of mission codes, with overlapping letter having different meanings. This would imply the size classification code (Q/A/B/F/W) be a leading qualifier on the mission code. This will just be confusing I think. So I've been ignoring the it.
 
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I end up with 12 codes (navy fleet, navy independent, navy defense, navy auxiliary, commercial trader, commercial freighter, commercial liner, commercial resource, commercial general, non-comm lab, non-comm scout. non-comm private).
13.
Add non-commercial courier, which can potentially be (but not necessarily always be) a "private" purpose.

Scout/Couriers and Express Boats would certainly fall into this category, but other non-commercial courier ships can also be given the role as well (including small craft for interplanetary courier duties). Couriers are important enough (methinks) for them to get their own category because it is a role different from others following "the mail must get through!" mentality/purpose which doesn't align all that cleanly with the others.

Yes, you can have multi-role ships like Scout/Couriers which do both depending on need, but they usually aren't going to be doing both simultaneously.

Naval courier falls under navy auxiliary.
Commercial courier falls under commercial trader (or even just commercial general if hyper specialized).
But in non-commercial service it really ought to have its own category because it is a pretty purpose built mission.
 
But yeah, then when we shift into the Imperial Navy, the patrol ship is not there at all -- the Close Escort takes over.

And the Close Escort was designed as a Merchant Convoy escort - and when it gets pressed into fleet duty in some Close Escorting (e.g. Anti-fighter/gunboat) role, it is said to fair poorly.
 
Since Destroyers and Escorts are not even secondary, then yeah. Makes me wonder what Destroyers are designed to Destroy that other ships aren't designed to Destroy, though.

This goes back to the core of the BCS Fleet debate: Is there some mode of attack or weapon system that another ship can help protect a fleet or other vessel against? If Torpedoes/Missiles are a meaningful attack mode that can do non-trivial damage to Capitals, or if a Fighter/Gunboat can mount a meaningful non-trivial attack against a Capital, then the Fleet Escort-Cruiser/Destroyer has a potential traditional role. If not, then is there some other attack mode that they can be designed to defend against?

Most Capitals rely on Meson Spinals and/or P-Accel Spinals as a primary attack mode; an appropriate damper-screen seems to be the only meaningful defense (or armor in the case of the P-Accel) against such an attack. I do not see an escort vessel being able to help defend against these attacks. If a Capital can be armored well enough to shrug off most other attack modes, what would an Escort defend against?

Certainly a Capital's sensor antennae and other surface mounted components could be vulnerable, but would that warrant a dedicated defensive-class, and how large and/or armed/armored would it need to be to screen the Capitals from such an attack?

But yes, Corvettes are below Frigates, and to me they seem to be on the same level as Escorts, but with a different mission.
T5: Patrol Ships look for trouble by definition

Because of their original tag name "Cruiser", and because they operate as pickets, customs, and patrol, their primary role appears to NOT be defensive, but rather patrol -- they're looking for trouble. Therefore, they qualify as Corvette rather than Escort.
  • Corvettes would likely attack small hostiles (Corsairs/Privateers) or pursue blockade-runners, or "patrol" looking for such (i.e. Picket Ships).
  • Escorts would provide defense and cover for transports or other valuable targets of opportunity.
 
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For example The naval service needs troop transports, which I've stuck into the commercial liner group. The non-comm needs a well armed (Naval Auxiliary / Fleet style) ship. Can these use the same codes because they are (essentially) the same design? Or should the be separate codes?

My brain very much want to force the design === primary mission code. If two (apparently different) ships end up with almost identical designs from a build point of view they should end up with the same primary mission code.

In the above case the Navy vessels should definitely have a qualifier/modifier distinguishing them as Military. (IIRC T5 has "N" as a modifier meaning "Naval").
 
S09: The Destroyers are Escorts
p14. The Chrysanthemum class destroyer escort is a small, fast vessel intended for fleet and squadron escort duties. ... This class of destroyer escort has been pressed into service in a variety of non-escort duties, including orbital patrols, police operations, garrison duties, and even limited strike missions.​
p15. [Fer de Lance] ...mid-sized escort vessel expressly for close protection of unarmed transport craft. ... this type of vessel can be found escorting most squadrons as well as more typical convoys.​
p16. The Midu Agashaam class destroyer is a streamlined escort vessel intended to supplement fleet defenses with anti-fighter and anti-small craft ships.​

Since their main purpose is to escort, they are Escorts, albeit multipurpose with some strike capability -- but their role is defense, not offense, so they are Escorts, not Corvettes. The "Destroyer" moniker might allude to them acting as an anti-fighter and anti-small craft screen.

In summary:
  • Frigates = Major Offensive
  • Corvettes = Minor Offensive
  • Fleet Escort/Destroyer - Major Defensive
  • Destroyer Escort = Multi-mission Minor Defensive/Offensive
  • Escorts = Minor Defensive
 
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Honestly most of these are moot as the roles tie to doctrine.

Consider the Escort.

Escorting what against whom?

Does a Tigress need an escort?

If an Escort is designed to engage fighters, are fighters even an actual threat worth defending against? How do you specialize against fighters?

The modern Aegis escort cruisers are (mostly) anti-air focused, specializing against aircraft and missiles. That's all well and good because an Aegis ship can fire against an anti-ship missile heading for, say, the Aircraft Carrier. But in HG, you can't augment the missile defense of one ship with another ship. So, the attackers can ignore the escorts and smother their target with all the missiles they want.

Since a ship can't help another ship defend against missiles, there would be no doctrine built up around that concept. Anti-fighter role, since, in theory, there can be something called a fighter, sure. But not an anti-missile role.

So, what does an escort do for a battle group?

Now, sure, there could be a convoy escort. A ship that accompanies other ships as they transit to and from Jump Space. But, that may well be argued to be more a "patrol" concept than a escort. They don't necessarily escort a specific ship, rather they patrol the space lane to keep intruders at bay. Ships in Jump space do not need an escort, and, honestly, if you don't have "space superiority", it's not wise to send a bunch of unarmed merchants in to uncontrolled space. So "escorting" them through Jump space doesn't make that much sense. Better to arrive early with the fleet and clear out any threat before the fleet train arrives.

Similar to having a minesweeping or mine laying ship. We don't have mines. I don't know, particularly with HG rules, if mines are a viable "thing" anyway. No mines, no doctrine for mine laying/sweeping, no dedicated ships.

So, anyway, the point is doctrine is driven by need. No doctrine, no mission, no ship. With the needs and doctrines being sussed out first (granted they can vary over time), you can't really come up with a coding system.

Consider, and I may be wrong, but it's my understanding that the Soviet military is very coarse, and very top down. That, for example, their armor groups have dedicated "leader" tanks that manage hierarchy of command and control and communication. The anecdote was that as a NATO defender, kill the tank with all of the antennas, and the rest of the tanks stop (I'm sure not literally, but effectively). Soviet doctrine mandated this kind of role for one of the tanks, thus they have a "specialized" Tank Leader model to fill that role. I'm sure it's just a normal tank with extra radios, but it is what it is. Purpose built and designed. Perhaps it carries less ammunition because they replaced some of the storage with the extra radios. Who knows, it's meant as an example.

So, thus my harping on doctrine. Doctrine drives design and mission.
 
This goes back to the core of the BCS Fleet debate: Is there some mode of attack or weapon system that another ship can help protect a fleet or other vessel against? If Torpedoes/Missiles are a meaningful attack mode that can do non-trivial damage to Capitals, or if a Fighter/Gunboat can mount a meaningful non-trivial attack against a Capital, then the Fleet Escort-Cruiser/Destroyer has a potential traditional role. If not, then is there some other attack mode that they can be designed to defend against?
This runs quickly into several meta-game issues which are only partly addressed by several different versions of Traveller.

The CT High Guard rules (and Book 2) have a defined set of weapons. This makes designing ships easier, and makes the ship to ship combat easier to manage. But it the limitations constrain the types of ships you can build. So now we're discussing the doctrine driven by design system.

If you start using FF&F or GURPS Vehicles to design ships, you get a much different set of design parameters. From here you can build weapons that a fighter craft can carry that will damage a large capital ship.

I'll defer to Rob about the Starship weapons design system for T5, but it looks reasonably complicated.
 
How you utilize close escorts depends a great deal on what set of combat rules are applied.

I'd certainly assign some to Tigressii.
 
This is a cross-post & modification of my Post #6 on the Naval History Terminology Thread as it relates to Traveller Ship Codes:

Traveller seems to divide its naval vessels into the following broad categories:
  • ACS – Colonial/Provincial/Planetary Assets (small-ship universe)
  • BCS – Capital/Imperial Assets (big-ship universe)
With Traveller’s divide into ACS and BCS ships, it seems that the ACS Naval Ships have traditionally drawn their terminology from a generalized version of the pre-1970’s USN Cold War usage, and the BCS ships use the post-1970’s Cold War terminology as their basis.

ACS – Colonial/Provincial/Planetary Assets ("small-ship universe")
  1. “Primary” = (Colonial) Cruiser -OR- Monitor (Heavy/Armored) (800-2000 ton)
  2. “Major” = Frigate -OR- Defender/Destroyer (Light/Fast/Attack) (600-1000 ton)
  3. “Minor” = Corvette -OR- Escort (anti-piracy / local patrol and action) (under 800 ton)

BCS – Capital/Imperial Assets ("big-ship universe")
  1. “Primary” = Capital/Primary = Battleship (largest/best are Dreadnoughts) (100 kton +)
  2. “Major” = Capital (“Imperial”) Cruiser (various classes) (20 – 100 kton)
  3. “Minor” = Fleet Escorts (Escort Cruiser/Destroyer or other Auxiliary) (5-10 kton or less) – equivalent to ACS “Colonial Cruiser” size – minor combatant

Putting these together (in decreasing size):
  1. BCS Capital/Primary “Battleship” ("Dreadnought" = Best-in-Class) ( - Principal Offensive - )
  2. BCS Capital Cruiser ( - Major Offensive - )
  3. BCS Fleet Escort ("Escort Cruiser" / Fleet Destroyer) ( - Minor Defensive - )
  4. ACS "Colonial" Cruiser * ( - Principal Offensive - ) // Monitor ( - Principal Defensive (Local) - )
  5. ACS Frigate ( - Major Offensive - ) // Defender ( - Major Defensive (Local) - ) -OR- Destroyer ( - Major Offensive/Defensive (Jump) - )
  6. ACS Corvette ( - Minor Offensive - ) // Escort (Close/Gunned/Destroyer Escort) ( - Minor Defensive - )
  7. ACS Gunboat or Torpedo Boat ( - Minor Offensive (Rider) - ) // SDB ( - Minor Defensive (Local) - )
* Note for ACS: CT, MT, and T5 have referred to naval small-ship universe cruisers explicitly in-print in 800, 1000, 1200, and 2000 ton sizes.


It seems that whereas ACS ships have the Sub-Categories of Principal, Major and Minor Combatants under two overarching categories: Offensive and Defensive, BCS ships seem to have only a single Overarching Category comprising both Offensive and Defensive operations-classes. This being the case, this makes the ACS Colonial Cruiser (a Principal Offensive under ACS) able to fill the role of a Minor Offensive equivalent under BCS, as it is potentially in the same size category as a BCS Minor.
 
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This runs quickly into several meta-game issues which are only partly addressed by several different versions of Traveller.

The CT High Guard rules (and Book 2) have a defined set of weapons. This makes designing ships easier, and makes the ship to ship combat easier to manage. But it the limitations constrain the types of ships you can build. So now we're discussing the doctrine driven by design system.

If you start using FF&F or GURPS Vehicles to design ships, you get a much different set of design parameters. From here you can build weapons that a fighter craft can carry that will damage a large capital ship.

I'll defer to Rob about the Starship weapons design system for T5, but it looks reasonably complicated.

Marc's general target of complexity was somewhere around MegaTraveller -- so, more choices than classic Traveller, but with less design complexity than FF&S. Generally, he used the design tables from MegaTraveller to generalize and develop a set of mini-builders.
 
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So, what does an escort do for a battle group?
In a Traveller context, the service provided is to screen the battle group.

The escorts protect the flanks, meaning that no "large" adversary can approach the battle group undetected.
So the escort is the front line and the rest of the battle group is in the reserve (HG styled combat).
This then denies an opponent the opportunity for a first turn contact attack on the battle group's primary ships.
You can "surprise kill" an escort (or few), but you can't surprise kill the primary ships of the battle group during the first turn due to the dispersion pattern of escorts around the battle group. That then buys the primary ships enough time to organize and orient to meet the threat.

So basically ... picket duty.
 
Specific issues I have with this suggestion, which I like, but still have concerns.

Same here. The exercise was useful for me, but left unresolved issues.

The codes I select for the wiki table version are based upon previous canon, but I'm not married to them. If it makes the process work better to select one of the T5 letter codes for a given row, and this makes the wiki as strict subset of the T5 definitions I approve of that.

First, an Argument for High Guard 2

And I believe that (conservatively) at least 50% of all Traveller starship designs are High Guard designs, so their mission codes carry extreme weight.

Consider that, if we went with the High Guard mission codes, that a high number of ship designs on the wiki would not have to be changed at all. That's a very strong argument. Moreover, it's an easy standard to MAP to something like T5. "The mapping of HG to T5's mission codes goes something like this..." and we have a page that includes describing generally what Traveller ship missions are, how they influence design, and how the two systems relate, and what variations exist in related rules systems.


Next, an Argument for High Guard 3

At the same time, I believe that the "Classic" designs (A,C,K,L,M,R,S,T) have high recognition, so their mission codes have some sort of trumping power. Thankfully, I think modifying HG with many of the Classic codes doesn't really affect the HG coding system, but actually improves it via backwards compatibility.

Call it "HG3", but defer anything beyond the mission codes.


The Cruisers and Corsairs should be combined into the same group. They're both mobile independent operations ships. This way you also get things like the 800-ton mercenary cruiser and 1200 ton frontier cruiser. And the Privateers. All of which are very close in design.

This is OK. There is even precedent for this in Book 2. So I'm on board.

The Barge, Tender/Tug are not armed and should not be in the E - Escorts group. But see previous message about military/non-comm splits. This also affect the picket/patrols ships as armed non-comm ships.

You're right. Your split is better, let's go that route.

I'm not as as enthusiastic about keeping the K - Expedition ships and specific designs could be tossed into either the L or Y groups depending upon design.

I know. The thrust of this argument is its very high recognizability in the Traveller community, and a desire to leverage that. In a way, it contributes an inordinate amount of oomph to the setting, in a way that single letters seldom do. I think it's even more important than the old Type T and Type X. "T" is just unfortunate (paTrol cruiser), but happily easily mapped to Corvette.

I'd been putting the small craft under their appropriate working group (e.g. Trader, Transport, Navy Auxiliary) rather than having a separate primary code. Purpose trumps size. In properly defining ACS/BCS/FCS/WCS adding a QCS (Small class ship) for size up to about 200 tons but no jump drive for in-system work may be a thing.

I see the small craft under High Guard as well. This depends on how popular small craft are in proportion to starships... if we've got oodles of them, then yeah I can go the HG-like route.

As an aside: I've been trying to push for a single set of primary mission codes. You have stated there may be different codes for the different size classes. The ACS and BCS ships may have a different set of mission codes, with overlapping letter having different meanings. This would imply the size classification code (Q/A/B/F/W) be a leading qualifier on the mission code. This will just be confusing I think. So I've been ignoring the it.

Actually the BCS codes could be the same. They're listed in Agent of the Imperium, but Marc's told me that they are not official mission codes -- they're informal terms used in conversation.

Since Marc's BCS rules are still incubating (and I'll start a new thread on that), we can lobby for a uniform code set.
 
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In a Traveller context, the service provided is to screen the battle group.
In that case you don't need much more than a fast sensor ship, yes? It's not so much a combat vessel as an E-2 Hawkeye, acting as the eyes of the fleet to pre-identify the combatants that the fleet knows is out there to something with a little more clarity than a "mark 2 fuzzy blob".

It would be an interesting design, from a TNE point of view, to have a forward fire director, sensor ship that's used to control missile sent by larger ships farther back. In TNE, you can hand off sensor contacts and missile control. So, you would have a larger launcher/magazine ship in the back, out of lock on, sending volleys of missiles forward to be handed off to the sensor and director ships, acting much like forward observers.

I dunno if it would work or not. You'd have ostensibly faster, cheaper, ships, with smaller target profiles on the front line ideally dodging more fire than they take, yet with "Cruiser" fire power since it can control cruiser level missile salvos.
 
I think the ACS/BCS distinction is very artificial. I don't see how you can have both ACS and BCS in the same "universe". Your ACS fleet is going to treated as popcorn to a BCS fleet. Seems to me you have either a ACS universe, or a BCS universe and then rate accordingly from that.
 
I think the ACS/BCS distinction is very artificial. I don't see how you can have both ACS and BCS in the same "universe". Your ACS fleet is going to treated as popcorn to a BCS fleet. Seems to me you have either a ACS universe, or a BCS universe and then rate accordingly from that.
It might be almost completely different than that.

Consider instead that ACS is the design system, and BCS specifically adds capital ships.
 
Consider instead that ACS is the design system, and BCS specifically adds capital ships.
My point is that an ACS "Battleship/Cruiser/whatever" is a meaningless statement compared to a BCS "Battleship/Cruiser/whatever". You can call them whatever you like, but there's an implied equivalency when you use the same terms for different items. I submit a 5000 ton BB is quite different form a 250,000 ton BB.
 
My point is that an ACS "Battleship/Cruiser/whatever" is a meaningless statement compared to a BCS "Battleship/Cruiser/whatever". You can call them whatever you like, but there's an implied equivalency when you use the same terms for different items. I submit a 5000 ton BB is quite different form a 250,000 ton BB.

Agreed.

But remember there are no BBs under ACS. ALL BBs are BCS. The overlap between ACS and BCS comes with the Large ACS/Small BCS Cruiser Classes. An ACS (Colonial) Cruiser is in the same general size category as a BCS Minor/Escort Cruiser/Fleet Destroyer. The Cruiser classification has always had a fairly wide range of specializations and sub-classes.
 
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