Difference beween Escort Destroyer and Fleet Destroyer?

[Hal]

Hello Folks,
Just tapping into the group mind on a minor question...

Fleet Destroyers are usually defined as those that can keep up with some sort of arbitrary Fleet speed (in this case, I think Jump-4). Generally, in order to be able to have a Jump-4 capability AND be able to engage in Destroyer activities, the ship's volume has to be somewhere in the vicinity of about 5,000 dTons right?

What about Escort Destroyers? Per Traveller's Aide #7, it seems that the definition of an Escort Destroyer is something that the Fleet Destroyer is not. It also seems to imply that it is any destroyer hull less than the 5,000 in the sense that tonnage can be between 1,000 to 5,000 dTons.

There was also mention of the fact that certain Destroyers tasked with escort duties tend not to have the heavier weapons, while the Fleet Destroyers tend to have heavier weapons.

So, if civilian ships tend not to be any faster (as a rule) than Jump-2, might not the Escort Destroyers be built more along the lines of either a smaller hull with Jump 2 capabilities and lighter weapons (More turret batteries than weapon bays or heavy weapons) - or both, while the fleet versions tend to be Jump-4 and have a mix of either heavier armor, heavier weapons, or some combination of both (where possible)?

I've created a Neyahuu class Destroyer, tentatively intended to be a Fleet Destroyer. Now I have to create some Destroyer Escorts for my TO&E for my Traveller Universe.

So, what are your thoughts on what a Fleet Destroyer should be versus what a Destroyer Escort should be - whether using CT ship building rules, MT ship building rules, GURPS Traveller ship building rules, or any other game version of Traveller.

Let's see what we can come up with here shall we?

Note: Just for giggles? Try to imagine life aboard the ships you're proposing or designing. Try to imagine having to set up a perimeter watch around your ship in the event you are in a neutral port or a civilian port or what have you. Try to imagine having to set up a watch bill to schedule what crew are on duty at any given time in order to run your ship 24/7.

 

[flykiller]

what a Fleet Destroyer should be versus what a Destroyer Escort should be

historically a torpedo boat destroyer was tasked with defending major fleet elements against torpedo boat attacks. this was necessary because 1) torpedo boats carried weapons that could inflict major damage on major warships and 2) major warships had difficulty defending themselves against these attacks and 3) the only cost-efficient solution was to build torpedo boat destroyers.

in traveller this dynamic does not exist.

as time went on destroyers came to be regarded as aggressive and available for probing and screening missions and, to some degree, expendable.

in traveller this dynamic exists.

you may wish to discontinue the destroyer concept and instead think of such ships as scouts or screens. a fleet scout would attached to a fleet to perform scouting and screening duties for that fleet (and thus have that fleet's jump rating), while an escort would perform scouting and screening duties for a convoy (and thus have relevant-only jump capability, perhaps only 2 or even 1). at the planetary echelon scouts and escorts would be indistinguishable from sdb's, though jump-capable boats might be assigned such duties from time to time.

 

[Xerxeskingofking]

So, what are your thoughts on what a Fleet Destroyer should be versus what a Destroyer Escort should be - whether using CT ship building rules, MT ship building rules, GURPS Traveller ship building rules, or any other game version of Traveller.

Let's see what we can come up with here shall we?

Note: Just for giggles? Try to imagine life aboard the ships you're proposing or designing. Try to imagine having to set up a perimeter watch around your ship in the event you are in a neutral port or a civilian port or what have you. Try to imagine having to set up a watch bill to schedule what crew are on duty at any given time in order to run your ship 24/7.

My thoughts (mainly system independent, so at least I think they are)

I'd say J2 or J3 ships, with a design emphasis on endurance. they should be streamlined, have ample fuel stocks and cargo space to ensure they can go months without needing a resupply. energy weapons might be preferred over missiles. Armour should be moderate, with enough to weather fire form pirate ships armed with light weapons.

At least one smallcraft for making customs inspections. Enough crew to be able to generate a customs inspection team without leaving critical systems unmanned (and to be able to weather the odd loss to accidents & Klingons). the ship should be "overcrewed", with a few more of everybody, and have its own medical team, QM's dept, ect, where a Fleet vessel might be able to offload these functions onto auxiliary ships.

the basic idea is that you can task the ship to go protect trade ships, and it can go off and potter about for six months following trade routes, and it needs nothing it cant buy over the counter (like foodstuffs).

 

[Hal]

SECTOR FLEET gives us a rough TO&E in the sense that it will say how many of what types of ships are to be used. I've always wondered why the Patrol Cruiser type T never seems to figure prominently in any of the organizational details.

This is largely why I brought this topic up here - to find out what might be the parameters necessary in a "successful design". I'm also of a mind to use the local ship yard technology for building any of the ship classes where possible for the Planetary navies, and a mix of "old" technology (ie Traveller Tech level 14) ships for those hulls that function as a "subsector naval reserve" rather than active Imperial Navy. One patrols, the other engages in training and keeping their fleet together in case of an emergency.

I've noted that in Fifth Frontier War, the ships were required to be able to transport battalion and larger sized ground fighting forces - seemingly inherent in its organization structure rather than needing a transport auxiliary (but since each counter MIGHT actually have freighters that can double as troop transports, that's not always a safe assumption to make!)

I try to make it such that Destroyers have at least a full platoon of marines aboard, and larger ships will have more capacity for carrying troops on board. Granted, a lot of my thinking is shaped by the GURPS TRAVELLER methodology, and I wish that Mongoose Traveller had run with the ball in having the same kind of modules that GURPS TRAVELLER did for its space ships. It's kind of neat being able to say that a ship has three brigs, a Battlesuit morgue, a Barracks Module, etc. It is also nice to be able to have Olympic sized pools aboard luxury liners etc. But - that's neither here nor there.

I think I'll go with the following guidelines then.

Most of the Escort Destroyers will largely be either old Fleet Destroyers that had to keep up with Jump-3 fleets back in the day, or they will be purpose built with lesser jump legs to keep pace with the merchant ships. They may be required to run anti-smuggling and anti-piracy patrols - but because of the anti-smuggling requirements, I suspect that the destroyers will constantly be checking Jump Emergence flashes are are not consistent with "Merchant Traffic". What constitutes "Merchant traffic?"

Simple enough - the adage "Time is money" means that many of the merchants are going to want to take shortest time duration trips, which means they'll want to appear closely near the ports they're going to and from. A ship that exits jump space in the outer orbits either has a bad navigator, or the ship doesn't really want to appear near sensors (such as smuggling etc). Likewise, if a "boat" is engaged in intrasystem asteroid mining, such a craft might have a ready made cover for smuggling - long periods of time outside starport sensors, hidden from normal view and so forth. So, an anti-smuggling patrol might routinely stop boats just to be meticulous in their duties.

That reminds me - I should open up a thread on "how does one smuggle in the Imperium", making it system agnostic, and using concepts and/or ideas that can be implemented to engage in the act of smuggling.

For instance, if I were to launch smuggled goods out my cargo bay door, attach an IFF style beacon to it, record its trajectory etc so that I can recover the goods later on - I'd have the perfect way to slide such smuggled goods past the sensors of anti-smuggling forces. I don't have the goods in my hold, I know where the goods are going to be (which means the navigator had better make his skill roll in determining the trajectory of the launched smuggled goods!), and I can either pick it up at its point later on, or have someone else pick it up after they get a coded message on where to look for it.

Ah well...

Specs for the Escort Destroyers: Tonnage ranges between 1 to 5 thousand dTons. Crew somewhat larger than necessary for purposes of potential boarding actions and/or inspections. Keep the ship logistically easy to supply, which means little in the way of missile armaments and such. Armor should be only good enough to handle in a half hearted way, larger destroyer style attackers, but be reasonably well armored to handle sub-1000 dTon enemy hulls and armaments. In addition, since these ships will be engaged in convoy duties, they should have a fair number of auxiliary craft to sweep for hidden foes ahead of the convey itself. Not exactly "light carriers per se, but over-represented by fighters more so than a fleet Destroyer might carry.

Any thoughts on how you might want to change the mission profile a bit or introduce a different approach? What I will do is build at least TWO different hull classes, since I'm sure that "experimentation" with new tactical doctrines will result in ships being designed for different tactical approaches to the same problem.

 

[kilemall]

All right, I would start with span of control to determine what the TO&E and mission structure is.

In other words, if you want to do ship captain, then someone plays the captain and other players are officers or key personnel.

If you want system command or squadron command, then admiral/commodore and most of the other players are other ship captains.

Decide your game scale, and then build forces and missions to match.

 

[blair]

I go by the implied Supplement 9 guideline that destroyer escorts are 1000 tons and below, but depart from S9 on destroyers, which I think of as 1000-1999t ships of fleet-standard performance with a missile bay.

To continue the sequence, for me escorts run 2-10kt with multiple missile bays, dampers, and maybe a repulsor or two; frigates go 10-20kt with anything but spinal mounts, typically with missile bays taking half or more of the weapon slots.

Again, this is "main sequence" of TL15, J-4, agility-6, comp-9/J ships with enough armor and bulk to avoid automatic critical hits or grave damage (700t and armor-4 for most purposes), meant for squadron service. Ships that trade those things off for specialized missions get other designations: scouts, intruders, corvettes, gunboats, monitors, and so forth.

 

[blair]

My own rationale is that there's a strong bias in planning towards units that can operate with the fleet, which means fleet-standard ships are what gets built and deployed. Subsector and local forces, with more focused needs and more constrained resources probably would turn out lower-jump escorts if they could. The main constraints are that small ships run out of hardpoints fast, and state-of-the-art computers eat small-ship budgets alive: a comp9/fib and its power supply represent about a third of the cost of a 1000t DE.

 

[Hal]

Hmmm...

Just had an epiphany of sorts.

I purchased a copy of GRAND FLEET some years back prior to the publication of SECTOR FLEET. Both PDF's were by the same authors, although they aren't IDENTICAL, they are largely the same. It seems that the one is a foundation for the other, seeing as GRAND FLEET was published first.

GRAND FLEET Has this to say about subsector fleets:

"Subsector Destroyer Flotilla
6-8 Fleet Destroyers (3000t) usually grouped as 2 squadrons
6-8 Escort Destroyers (1000t) usually deployed independently
Subsector Patrol Assets
10-20 Patrol Cruisers or Close Escorts (3-400t) grouped
administratively as squadrons of 3-4 but deployed individually"

Maybe this might be the key I was looking to find.

 

[blair]

Right, those correspond to HG2/S9 types, plus the Type T.

Under HG2, at least, it's hard to build a balanced warship at canonical TL15 fleet standard in the 2-5k range: if you're not going to be target practice for nuclear missiles, you have to invest in defenses, and those defenses (dampers and repulsors) are tonnage-based rather than percentage-based. As a result, you get ships low on punch, like:


Class: DH5000-96209
Type: destroyer-gunboat
Architect: wbh
Tech Level: 15

USP
DH-E1469J5-480905-96209-0 MCr 4,036.050 5 KTons
Bat Bear 1 1 111 2 Crew: 93
Bat 1 1 111 2 TL: 15

Cargo: 72 Passengers: 6 Crew Sections: 5 of 19 Fuel: 2,450 EP: 450 Agility: 6 Marines: 33
Craft: 2 x 50T BAs
Fuel Treatment: Fuel Scoops and On Board Fuel Purification

Architects Fee: MCr 39.361 Cost in Quantity: MCr 3,248.840


That's for ships with the stuff for independent action, of course. If you do a pure screening/escort ship that operates in mass and can depend on a tender for boat pool, Marines, ammo, barbershop and geedunk you can do better, although then maybe a bunch of A-size ships with more armor and no screen make sense. Likewise, a bigger ship gets you a lot more capability per ton/credit/crew-sophont, even though once you pass 10,000 tons you'd better add meson screens.

 

[Hal]

So the trick Blair, is to create the mission profile for the ships in question and take it from there.

For instance, a 1000 dton hull with but a single bay weapon, isn't really going to scare anyone other than the smaller ships that can't go up against that weapon and survive right? If using HIGH GUARD battle system, such a bay weapon gets "scrubbed" by low grade weapon hits when you have but one weapon! Having a 2,000 dton hull with a single bay weapon and 10 turrets becomes a bit more of a thorny problem right?

Can a Jump-2 destroyer with little to no armor against the big guns, but decent enough armor against smaller guns (less than 1000 dton weapon batteries) - be more than a match for corsairs, other raiders built on up to 2,000 dton hulls not ready for a HIGH G capability?

What if there were two fighter bays in that destroyer, along with some cutter bays? Would the extra platforms help in any small scale battle?

On idea that I visited once upon a time were "Jeep Carriers". Not intended to go head to head against major line of battle hulls, or even enemy commerce raiders in a big way, their ability to have a fighter screen of sensors more than made up for their lack of major punch. Being able to field 20 fighters unexpectedly, was like having a 2,000 dton hull appear unexpectedly and without warning.

For High Guard rules system, such a jeep carrier might not be worth the while. In GURPS TRAVELLER, where missiles at high velocity can cause serious damage, they might well be. Heavy Laser armed fighters can be especially nasty in GURPS. What might such a Jeep carrier do in say, MgT1 or MgT2? T20? T5? I couldn't say.

For purposes of SECTOR FLEET's TO&E, that' becomes the problem. How to set the mission parameters, and how to build them to meet those specifications.

On that note... time for me to nod off.

 

[Garyius2003]

Since Traveller ship classes appear to use the names of WWII US Navy analogues, the WWII destroyer escort would have similar weapons to a destroyer, same torpedoes and 3" v 5" guns, with less speed but a much longer range.

Traveller used close escorts for part of the traditional DE role, but classic Traveller ended up with both, with the destroyer not being twice as good as the DE even though it cost twice as much. There isn't a good reason in classic to have a destroyer instead of biting the budget bullet and buy the light cruiser.

Mongoose Traveller upends this with their torpedoes

 

[Murph]

I would look at them as Escort ships have a lighter weapon load out with the intention of being fleet anti-missile ships much like the Atlanta class cruisers of WWII were fleet AA ships rather than regular cruisers. Fleet destroyers would be more heavily armed, and more able to take on some of the independent cruising duties.

 

[kilemall]

I'd go with the distinction that fleet destroyers are built for maneuver and jump capability to match mainline units and effectively escort/protect/screen the fleet from smaller threats and detection, and escort destroyers are more for wartime expedience, cheaper to make as they don't have battle line duties or maybe not built for 80 years plus service, suited for convoy escort and long-term independent patrol.

 

[Ulsyus]

So the trick Blair, is to create the mission profile for the ships in question and take it from there.

That's a pretty sound point to start from.

Here's some shooting-from-hip thoughts...

From another perspective, in times of peace merchantmen travel singly as that's enables them to work to their own most effective/efficient schedule.

Because they're all over a set area, even if it's a defined set of shipping lanes delineated by the Port or some other Authority. To prevent bad things from cropping up or to mitigate risks of various types, patrol ships are needed to cover those areas/lanes. Hence the patrol cruiser.

In times of war, conflict, or reduced civil order, merchants may group together in convoys for protection. Less efficient schedule-wise, but enables some collective survivability. To keep them safe from raiders, they could have any range of vessels with them from a smallish vessel (Fiery?) upwards. This is where I reckon you'd insert a Destroyer Escort. Large enough to cause grief of any regular-sized corsair, but small enough to have a few of them in a squadron and able to present a risk to smallish (400-300t?) raiders deep behind the FEBA.

The Fleet Destroyers then become the fleet picket vessels. Large enough to cause grief to scouts, swat fighters in small numbers out of the way, but small enough to have enough of them to spread the screen out ahead of the fleet to extend sensor coverage for the cruisers and capital vessels.

But it all comes back to what are they for, so back to to list the mission profile and extend an offer to the ship builders to then submit their designs and tenders for you to select from.

PS: What's the tonnage capacity of the A Class starports you're working with? An A Class that that can only produce a hull of not more than 5000dt isn't going to be much good for building you heavy cruisers unless the whole thing uses hull modules that operate with a jump bubble rather than a jump field...

 

[Condottiere]

Depends on doctrine.

Escort destroyers would be screening elements, usually specialized against one threat, minimal crewed, and built by the lowest bidding shipyard during wartime.

 

[Carlobrand]

In the Traveller setting, the threat zone is from planet to jump and then jump to planet, except in-system traffic. Any decent port will be policing its orbital space with fighters and such, so threats aren't going to be hanging around causing problems unless they're big enough to repel whatever the port sends up, which limits threats to opposing Naval ships and means the danger lies in jumping into someplace you didn't know was being visited by a raider before the Navy got word and sent something to chase it out.

Whether a jumping escort has any value in that context depends on whether it can make the exit from jump space in concert with the ships it is escorting and whether it can survive an encounter with whatever size raider happens to be there, long enough for the merchants to get to ground (or within the range of the planetary defense batteries). Wartime escorts for merchantmen need to be small, agile, and heavily armored to fill the role, but they can give up a bit in jump range to achieve that since the merchantmen they accompany tend to have shorter jump ranges. The escorts won't be cheap.

As to the places without adequate ports - that's about the only place that Gazelle type escorts have any value, since that's the only place that the opponents in their weight class are likely to be hanging out. At that, they'll still get squished pretty quick if it's wartime and they are unlucky enough to encounter an opposing destroyer.

 

[Shadowrunner]

For me, tonnage is the criteria, so a Destroyer Escort is around 1000 - 2000 tons e.g. Fer de Lance or Chrysanthemum. A Destroyer is around 3000+ e.g Midu Agashaam. I'm quite generous with the term "Cruiser", around 7kton +.

 

[phavoc]

Hello Folks,
Just tapping into the group mind on a minor question...

Fleet Destroyers are usually defined as those that can keep up with some sort of arbitrary Fleet speed (in this case, I think Jump-4). Generally, in order to be able to have a Jump-4 capability AND be able to engage in Destroyer activities, the ship's volume has to be somewhere in the vicinity of about 5,000 dTons right?

What about Escort Destroyers? Per Traveller's Aide #7, it seems that the definition of an Escort Destroyer is something that the Fleet Destroyer is not. It also seems to imply that it is any destroyer hull less than the 5,000 in the sense that tonnage can be between 1,000 to 5,000 dTons.

There was also mention of the fact that certain Destroyers tasked with escort duties tend not to have the heavier weapons, while the Fleet Destroyers tend to have heavier weapons.

So, if civilian ships tend not to be any faster (as a rule) than Jump-2, might not the Escort Destroyers be built more along the lines of either a smaller hull with Jump 2 capabilities and lighter weapons (More turret batteries than weapon bays or heavy weapons) - or both, while the fleet versions tend to be Jump-4 and have a mix of either heavier armor, heavier weapons, or some combination of both (where possible)?

I've created a Neyahuu class Destroyer, tentatively intended to be a Fleet Destroyer. Now I have to create some Destroyer Escorts for my TO&E for my Traveller Universe.

So, what are your thoughts on what a Fleet Destroyer should be versus what a Destroyer Escort should be - whether using CT ship building rules, MT ship building rules, GURPS Traveller ship building rules, or any other game version of Traveller.

Let's see what we can come up with here shall we?

Note: Just for giggles? Try to imagine life aboard the ships you're proposing or designing. Try to imagine having to set up a perimeter watch around your ship in the event you are in a neutral port or a civilian port or what have you. Try to imagine having to set up a watch bill to schedule what crew are on duty at any given time in order to run your ship 24/7.

In my mind a fleet destroyer (DD) would be a fairly balanced ship able to do excel at nothing, but also not be bad at everything. It would have the jump capability of the mainline battle fleet (typically J-4), it would do 6G (DD's are screening and scouting elements), it would have light armor, light defenses and a light armament. Which pretty much sums up the role of most destroyers in the wet navy. And it may pack a punch (torps or heavy energy armament), but not at the expense of everything else.

A destroyer escort (DE) MAY be J-4, but most likely J-3, it MAY have 6G, but most likely 5G, it would be lightly armed and it's armament would be mostly a mix of lasers/sand with perhaps a few missile launchers thrown in for good measure. It's primary task is not to be part of the mainline fleets. It would find most of it's jobs playing escorts to merchantmen, hunting down lowly pirates and performing patrols. It's not awful at anything, but it's not terribly good at anything either.

Tonnage of these ships would really depend on what naval books you are looking at, which determines the rough tonnage for the smaller craft. If the average battleship is around 200k Dtons, and a CA is around 60k Dtons, then you'd see a DD come in around 10k Dtons, and a DE between 3 & 7k Dtons. But, if your biggest dreadnought tops out at 100K dtons, and you are running in a smaller ship universe, then your DD should be around 3-5k Dtons and your DE around 1.5-3k Dtons. In any case it's enough tonnage to give it some weapons capabilities, but not to be a full threat to it's much larger brethren.

 

[Condottiere]

In Traveller, there is a huge disparity in tonnage between ship categorizations as compared to historical ones.

So it tends to be more about form follows function.

 

[GypsyComet]

My take:

Fleet Destroyers are a taskable element of a fleet. If the Admiral wants a flanking maneuver the Fleet Destroyers are up to the task and large enough to draw attention.

Escort Destroyers are fly swatters, intended to keep the little stuff from bothering *their* Capital ships. While the Admiral can, of course, issue commands directly to the DEs it will generally be a waste of his time; he orders the BBs and the DEs follow the BBs.