Striker Book 3 DS 6 Lasers Installment 2: towed Crew and Gun shield

[snrdg082102]

I am totally confused by Striker Book 3 DS 6 Lasers Step B Crew and Step D Weight for a gun shield.

DS 6 Step B. Crew page 18: "...; a towed laser has a crew of 1 per ton of total weapon weight (round fractions up)."

DS Step D. Weight page 19: The weight of a laser is the weight of the laser itself (Power Input x 0.066) + its fire control + the batteries for pulse lasers (1 x Power Input ) + the gun shield (0.07 x crew) if any.

I am obviously very very confused here.

 

[sabredog]

1) determine the weight of the laser w/out the gunshield - this gives you the crew size.

2) figure out the size of the gunshield with this crew number.

3) So long as you don't have to round up another crew member (not often, but it sometimes happens) you now have the weight of the gunshield and number of crew. If you have to round up a crew number because the weight of the shield puts you over the hump then add the extra crew and redo the size of the shield. I doubt you will have to round up again at this point.

The majority of lasers will be small enough that you don't have to take the extra step of rounding up the crew number after figuring the crew size more than once if at all.

 

[snrdg082102]

Thanks again for coming to my aid sabredog,

1) determine the weight of the laser w/out the gunshield - this gives you the crew size.

2) figure out the size of the gunshield with this crew number.

3) So long as you don't have to round up another crew member (not often, but it sometimes happens) you now have the weight of the gunshield and number of crew. If you have to round up a crew number because the weight of the shield puts you over the hump then add the extra crew and redo the size of the shield. I doubt you will have to round up again at this point.

The majority of lasers will be small enough that you don't have to take the extra step of rounding up the crew number after figuring the crew size more than once if at all.

To recap:

Calculate the base crew using roundup(laser weight (Power Input x 0.066) + its fire control + the batteries for pulse lasers (1 x Power Input

),0).

Calculate the gun shield weight per DS 6 Step D of .07 x Base Crew size.

Add the gun shield and recalculate the Crew if the crew size is larger add a crew member or members.

Recalculate gun shield size and hope the crew size doesn't change again.

Did I get the steps down?

Did I get the pulse laser battery weight calculation correct?

 

[aramis]

Looks right, Tom.

 

[snrdg082102]

Evening Aramis,

Looks right, Tom.

Thanks for the feedback that my summary looks right.

Unfortunately I don't think I have the pulse laser battery calculation figured out yet.

I'm working with a TL 9 towed pulse laser with 4 lenses that has a power input of 10 MW. The weapon system has both direct and point defense fire control systems.

Pulse laser weight = 10 MW x .066 = 0.66 tons
Gun carriage weight = 2.5 x 0.66 = 1.65 tons
TL 9 Direct FC weight = 0.05 tons
TL 9 Point Defense FC weight = 0.5 tons

Total weapon weight without the battery is is 2.86 tons and at this point has a crew of roundup(2.86,0) = 3.

Using my battery weight formula of 1 x Power Input of 10 MW the required battery weighs 10 tons. This seems a bit high to me.

Looking on DST page 10 the Battery table indicates that 1 kg of battery has a certain storage value based on technology level.

At TL 9 1 kg of pulse laser battery stores 2.25 MW/sec of power. To get 10 MW/sec I need to have 10/2.25 = 4.4444 kg of batteries. 4.4444 kg = 4.4444/1000 = 0.004444 tons.

To me the second calculation seems like a better fit

 

[Carlobrand]

...Unfortunately I don't think I have the pulse laser battery calculation figured out yet.

I'm working with a TL 9 towed pulse laser with 4 lenses that has a power input of 10 MW. The weapon system has both direct and point defense fire control systems.

Pulse laser weight = 10 MW x .066 = 0.66 tons
Gun carriage weight = 2.5 x 0.66 = 1.65 tons
TL 9 Direct FC weight = 0.05 tons
TL 9 Point Defense FC weight = 0.5 tons

Total weapon weight without the battery is is 2.86 tons and at this point has a crew of roundup(2.86,0) = 3.

Using my battery weight formula of 1 x Power Input of 10 MW the required battery weighs 10 tons. This seems a bit high to me.

Looking on DST page 10 the Battery table indicates that 1 kg of battery has a certain storage value based on technology level.

At TL 9 1 kg of pulse laser battery stores 2.25 MW/sec of power. To get 10 MW/sec I need to have 10/2.25 = 4.4444 kg of batteries. 4.4444 kg = 4.4444/1000 = 0.004444 tons.

To me the second calculation seems like a better fit

Why are you adding a CPR gun carriage? The CPR Carriage table is for CPR guns. CPR guns produce vicious recoil and need a carriage designed to absorb that punishment. The laser produces no recoil - well, nothing noticeable on the human level, anyway.

The rules state, "The weight of a laser is the weight of the laser itself, plus its fire control, plus its batteries (if a pulse laser), plus its gunshield (if any). The weight of the laser is .066 tons times its input in megawatts. The weights of fire control systems are listed in the fire control section. A gunshield weighs .07 tons per crewman." No mention of a carriage. I admit I'd have expected at least the wheels to weigh something, but it's not part of the rules, and there's nothing in Errata either.

(If you continue to the energy weapons, you find that they have their own carriage rules; they do not draw on the CPR carriage rules.)

So:
Pulse laser weight = 10 MW x .066 = 0.66 tons
You do not need a direct fire control
TL 9 Point Defense FC weight = 0.5 tons
plus batteries

(The TL9 PDFC serves as direct fire control too. You only need a separate direct fire control if you want fire control of different tech levels - as for example a tank with a TL15 DFC to maximize its weapon's range, and a TL9 PDFC for a basic level of point defense. A TL15 PDFC costs 2.5 million credits, which can be as much as a third to a half the price of an entire TL 15 armored vehicle, while the TL 9 PDFC is less than 1/10 that cost.)

Where do you get your first battery weight formula? The Striker Design Sequence Tables (DST) is what is used to calculate battery weight, so your second calculation is correct: you need 4.44 kg of batteries.

So, now you have a 10 MW 4-lens pulse laser with a weight of 1.164 tons.

Don't forget you need to bring power to the laser: the battery only accumulates power for the pulse function. (Thanks to that battery accumulation function, a single-pulse laser can produce four times the penetration for the same power as a beam laser, though it pays a price by losing the hit bonus the beam laser gets.) The need for power means the laser is usually either mounted on a vehicle - with the vehicle power plant supplying the needed power - or at some fixed defensive point supplied with power, such as the walls of a fortification. Towed lasers are unusual.

 

[snrdg082102]

Morning Carlobrand,

Thanks for the reply and holding my hand through the process

Why are you adding a CPR gun carriage? The CPR Carriage table is for CPR guns. CPR guns produce vicious recoil and need a carriage designed to absorb that punishment. The laser produces no recoil - well, nothing noticeable on the human level, anyway.

The gun carriage is going to have weight regardless of the weapon mounted and logically will be included in the weapon final weight calculation. The only reference to mount weight is the CPR gun carriage table.

In order to ask my question using an example I selected the, obviously now, incorrect value. I also thought about using the mortar requirement, but there is still the little issue of recoil that the CPR carriage table is compensating for.

With your question I've been doing a little more digging in CT without finding anything more about determining the weight of a laser gun carriage for a towed system. In TNE FF&S Mk I Mod 1, since the design sequence is similar, I discovered that lasers are normally mounted in turrets. However, Laser Design Step 10A states the carriage has the same weight as the laser being mounted.

I also checked in the MT: Referee's Manual states that mass driver guns, lasers, and fusion/plasma guns must be vehicle mounted.

Looking over the information I've dug up I have two recommendations:

Recommendation 1: Use the TNE FF&S Mk I Mod 1 requirement that the laser gun carriage weight = the laser weight (laser tube + fire control + pulse laser batteries + gun shield).

Recommendation 2: Restrict lasers to vehicles per MT: Referee's Manual.

However, since that is not official the carriage weight should not not be included.

The rules state, "The weight of a laser is the weight of the laser itself, plus its fire control, plus its batteries (if a pulse laser), plus its gun shield (if any). The weight of the laser is .066 tons times its input in megawatts. The weights of fire control systems are listed in the fire control section. A gun shield weighs .07 tons per crewman." No mention of a carriage. I admit I'd have expected at least the wheels to weigh something, but it's not part of the rules, and there's nothing in Errata either.

I'll agree and the laser gun carriage can be omitted for the calculations.

(If you continue to the energy weapons, you find that they have their own carriage rules; they do not draw on the CPR carriage rules.).

I just noticed the energy weapon gun carriage requirement.

So:
Pulse laser weight = 10 MW x .066 = 0.66 tons
You do not need a direct fire control
TL 9 Point Defense FC weight = 0.5 tons
plus batteries

(The TL9 PDFC serves as direct fire control too. You only need a separate direct fire control if you want fire control of different tech levels - as for example a tank with a TL15 DFC to maximize its weapon's range, and a TL9 PDFC for a basic level of point defense. A TL15 PDFC costs 2.5 million credits, which can be as much as a third to a half the price of an entire TL 15 armored vehicle, while the TL 9 PDFC is less than 1/10 that cost.).

I included both fire control systems based on the Striker Book 2 Rule 36 Point Defense A3 Dedicated Support range of 10 cm and B. PD against Direct Fire range of 15 cm.

Where do you get your first battery weight formula? The Striker Design Sequence Tables (DST) is what is used to calculate battery weight, so your second calculation is correct: you need 4.44 kg of batteries.

My first formula was based on the opening statement of: "A pulse laser must have batteries with an energy storage capacity in mega-watts-second equal to its input in megawatts." and not having figured out the Battery Table on DST page 10.

Thanks for confirming I finally figured out how to use the battery table.

So, now you have a 10 MW 4-lens pulse laser with a weight of 1.164 tons.

Don't forget you need to bring power to the laser: the battery only accumulates power for the pulse function. (Thanks to that battery accumulation function, a single-pulse laser can produce four times the penetration for the same power as a beam laser, though it pays a price by losing the hit bonus the beam laser gets.) The need for power means the laser is usually either mounted on a vehicle with the vehicle power plant supplying the needed power - or at some fixed defensive point supplied with power, such as the walls of a fortification. Towed lasers are unusual.

At least I know my calculation process is on the right track if not coming up with the same numbers.

Based on MT and TNE I had gathered that a towed system was unusual, however Striker Book 3 laser design sequence allows one to be created. I can see having a towed gun that can be installed in a location and power leads strung between the gun and power source. That way knocking out either the gun or power source would to a total loss.

Thanks again for the help.

 

[sabredog]

Re: the mysterious laser gun carriage.

The Striker design rules can be seen as a flowchart: when designing similar systems in rules you can infer that parts of the design sequences may carry over from the prior designs to the current one unless certain parts are specifically dropped off or replaced. An example would this gun carriage.

CPR gun designs (and other CPR-ish weapons and mass drivers) come before lasers and may include a carriage for towed weapons. Lasers come next and the rules say a carriage is required for towed lasers. No rules specify the carriage but the next sequence for energy weapons does specify rules for carriages for its towed type.

We can then reasonably infer that until energy weapons come along a gun carriage is a gun carriage, whether it be for a rocket launcher, cannon, or laser.

 

[snrdg082102]

Afternoon sabredog,

Another thank you is in order for your help with my questions.

Re: the mysterious laser gun carriage.

The Striker design rules can be seen as a flowchart: when designing similar systems in rules you can infer that parts of the design sequences may carry over from the prior designs to the current one unless certain parts are specifically dropped off or replaced. An example would this gun carriage.

CPR gun designs (and other CPR-ish weapons and mass drivers) come before lasers and may include a carriage for towed weapons. Lasers come next and the rules say a carriage is required for towed lasers. No rules specify the carriage but the next sequence for energy weapons does specify rules for carriages for its towed type.

We can then reasonably infer that until energy weapons come along a gun carriage is a gun carriage, whether it be for a rocket launcher, cannon, or laser.

Part of the reason my original example used the CPR gun carriage parameters was based on the theory that a towed laser would follow the established rules. My first inclination was to use the guidelines for a mortar. Then I went with the "All others" without taking recoil into consideration now I'm more inclined to use the mortar parameters.

Of course they would be unofficial rules, aka house rules, until made official.

Thanks again sabredog for the help.

 

[sabredog]

I have a lot of house rules, myself - anyone running Traveller does, so house-rule away. I think the mortar/MRL type carriage works better myself, but the only caveat is that a mortar "carriage" isn't usually towed. Some are, but a mortar carriage is a base plate and stand, with nominal "indirect fire control".

An MRL carriage is a little more complicated, provided it isn't just rails like a Katyusha has, but it's still pretty simple.

A towed laser might not need recoil dampening, but that isn't going to be part of the carriage, either. Recoil dampening systems will be part of the CPR gun itself, which is why mortars are so light and guns/howitzers are a lot heavier. The carriage will consist of the tow bar system, wheels, and the supporting framework. There may be spades built into the tow bars, lift legs for leveling and bracing the gun, etc, but the weight of the weapon determines the weight of the carriage - and lasers are pretty light.

I would recommend (but you can ignore it) you stick with the CPR carriage since it will be simulating a ruggedized, wheeled system for fully servicing the laser as a weapon placement - not just for holding it up. It will probably be pretty light weight since lasers tend to be (except the Godzilla-killing size, but then you should be using the high energy guns or rocket artillery if you need it that big) so it will not be the same thing you see some 105 howitzer mounted on.

But part of the fun of Traveller is playing with the rules, and while Striker is first and foremost a wargame and a supplement to role-playing second, it has a lot of potential when you play around with it. I've used it for combat resolution and vehicle/weapon/armor designs since it first came out and love it. It can be a wee merciless in the damage resolution for players, though, so I use CT combat for small arms fire and Striker for the rest.

 

[snrdg082102]

Evening sabredog,

Overall house rules a good, especially with the huge wiggle room Traveller allows. The issue I have with house rules is when a shared design doesn't mention how the rule is used and I can't recreate the design.

Of course I do seem to inadvertently make house rules by interpreting the rules differently.

I have a lot of house rules, myself - anyone running Traveller does, so house-rule away. I think the mortar/MRL type carriage works better myself, but the only caveat is that a mortar "carriage" isn't usually towed. Some are, but a mortar carriage is a base plate and stand, with nominal "indirect fire control".

An MRL carriage is a little more complicated, provided it isn't just rails like a Katyusha has, but it's still pretty simple.

A towed laser might not need recoil dampening, but that isn't going to be part of the carriage, either. Recoil dampening systems will be part of the CPR gun itself, which is why mortars are so light and guns/howitzers are a lot heavier. The carriage will consist of the tow bar system, wheels, and the supporting framework. There may be spades built into the tow bars, lift legs for leveling and bracing the gun, etc, but the weight of the weapon determines the weight of the carriage - and lasers are pretty light.

I would recommend (but you can ignore it) you stick with the CPR carriage since it will be simulating a ruggedized, wheeled system for fully servicing the laser as a weapon placement - not just for holding it up. It will probably be pretty light weight since lasers tend to be (except the Godzilla-killing size, but then you should be using the high energy guns or rocket artillery if you need it that big) so it will not be the same thing you see some 105 howitzer mounted on.

But part of the fun of Traveller is playing with the rules, and while Striker is first and foremost a wargame and a supplement to role-playing second, it has a lot of potential when you play around with it. I've used it for combat resolution and vehicle/weapon/armor designs since it first came out and love it. It can be a wee merciless in the damage resolution for players, though, so I use CT combat for small arms fire and Striker for the rest.

I'm going to stick with the mortar gun carriage modifiers since they make more sense to me.

How I see the laser gun carriage is similar to yours which is a way to move a laser not installed in a vehicle from point A to Point B and house everything but a power source.

Again thanks for the help.

 

[Carlobrand]

Re: the mysterious laser gun carriage.

The Striker design rules can be seen as a flowchart: when designing similar systems in rules you can infer that parts of the design sequences may carry over from the prior designs to the current one unless certain parts are specifically dropped off or replaced. An example would this gun carriage.

CPR gun designs (and other CPR-ish weapons and mass drivers) come before lasers and may include a carriage for towed weapons. Lasers come next and the rules say a carriage is required for towed lasers. No rules specify the carriage but the next sequence for energy weapons does specify rules for carriages for its towed type.

We can then reasonably infer that until energy weapons come along a gun carriage is a gun carriage, whether it be for a rocket launcher, cannon, or laser.

No, we can't. That's not a logical inference.

The design sequences are distinct; when one depends on another, it is specifically mentioned as depending on that other. Mass Drivers, the immediate prior design sequence, specifically states they're designed using the CPR design system with the noted exceptions. MRLs, the design sequence before that, specifically state they use the CPR system with the noted exceptions. That being the case, you cannot assume a dependence where none is described - nor is that logical, since the gun carriage is far hardier than is needed for a laser.

Lasers offer an option for a towed weapon but then do not describe the carriage. In fact, the rule describing the weapon's weight mentions the gunshield but omits any reference to a carriage. It is arguably an error, but slapping a laser on a carriage meant to handle the recoil of a high-velocity gun is neither within the rules nor a proper solution. And let's be clear about what's happening when a CPR gun fires - that recoil dampening system does not make it a recoilless weapon as far as the carriage is concerned; it simply reduces the shock of recoil.

Here's an image of a 155mm howitzer firing:
http://www.youtube.com/watch?v=kb3tfk8dxvU

My guess is, if that were a laser it would not need quite what that 155 is needing.

As to the comments regarding mortar carriages:

http://en.wikipedia.org/wiki/Mortier_120mm_Rayé_Tracté_Modèle_F1

http://en.wikipedia.org/wiki/240_mm_mortar_M240

Please note these very wheeled mortars. A mortar is not towed when it can be readily broken down into man-carryable parts, typically barrel, baseplate, mount and the sight/fire control. When it gets up past a certain size, it's mounted on wheels.

Here's a rather fancy wheeled mortar being used by the Marines:

http://www.youtube.com/watch?v=v5wE1HEtSLQ&feature=related

Fortunately, the idea of a towed direct-fire weapon is pretty absurd by the time lasers become available - combat is too mobile, the crew and weapon are too vulnerable, and it needs to be powered anyway so mounting it on whatever you plan to power it with is easiest. Generally the laser's vehicle mounted or in a fixed installation like a fortification.

 

[Carlobrand]

...In TNE FF&S Mk I Mod 1, since the design sequence is similar, I discovered that lasers are normally mounted in turrets. However, Laser Design Step 10A states the carriage has the same weight as the laser being mounted.

I can't speak to TNE, and I'd advise caution before mixing game systems.

...I included both fire control systems based on the Striker Book 2 Rule 36 Point Defense A3 Dedicated Support range of 10 cm and B. PD against Direct Fire range of 15 cm.

"3. Dedicated Support: When committed to dedicated support, the point defense weapon is locked onto a specific friendly vehicle or stand and will follow its movement. Any missiles, rockets, grenades, or indirect fire rounds aimed at the friendly unit or at any target within 10 cm of it [the friendly unit that you locked onto] may be engaged by the point defense weapon in an attempt to destroy them. The weapon makes one attack against indirect fire rounds per turn, and one attack against direct fire rounds per phase, as outlined below."

For example, you're in a vehicle mounting a TL15 RP-X gun and a TL 9 point defense fire control. You're locked onto a friendly tank about a kilometer off, well within direct fire range of your RP-X point defense weapon. There's an APC travelling 8 cm (80 meters) behind the tank you're protecting, and a second following behind - it's 11 cm (110 meters) behind the tank. Suddenly an enemy infantryman pops up from the brush and lets loose an RPG aimed at the first APC. Your point defense weapon detects it, locks on, and fires: you roll a 5 which, with your +3 to hit bonus for the RP-X, is just enough to destroy the RPG round. Unfortunately, the second APC faired less well - it was too far from the tank for your PD system to protect it when a second infantryman stood and fired his RPG.

Note that the design example of the Imperial Marine Grav APC documents a TL 9 PDFC and gives ranges for it that are identical to the ranges of a TL 9 direct fire control.

 

[snrdg082102]

Morning Carlobrand,

Thanks for the links and of course the assistance being provided.

No, we can't. That's not a logical inference.

The design sequences are distinct; when one depends on another, it is specifically mentioned as depending on that other. Mass Drivers, the immediate prior design sequence, specifically states they're designed using the CPR design system with the noted exceptions. MRLs, the design sequence before that, specifically state they use the CPR system with the noted exceptions. That being the case, you cannot assume a dependence where none is described - nor is that logical, since the gun carriage is far hardier than is needed for a laser.

The laser rules state that a laser weapon can either be mounted on a vehicle or towed. If towed then per the quoted previous rules there is a carriage of some sort that has a weight, volume, and price that must be included in the final weapon data for weight, volume, and price.




The design sequence for energy weapons following laser design has does have a way to include a gun carriage which follows the same basic process as for CPR gun carriages. Multiply the weapon weight and price by a specified number to get the carriage weight/volume and price. The difference is the numbers and instead of the using the carriage weight to calculate price one uses the weapons price x .1.

You are correct that my original thought to use the all other CPR gun parameters of 2.5 x weight and .25 x price was not the best solution but I had to start somewhere.

My experience is that military equipment is usually over-designed so having a carriage hardier than the equipment installed isn't an issue just a pain in the butt.


The only question that remains is what parameters are used to calculate a towed laser gun carriage which is allowed by the rules. As indicated both MT and TNE reference how lasers can be mounted. In MT a laser can only be vehicle mounted, while in TNE the carriage's weight/volume is equal to the weapons and price is 0.002 x the carriage's weight.

I could slap the MT rule that lasers can only be mounted on vehicles, or TNE rules for the carriage, (which usually need more tweaking to fit CT than I like to), or create my own based on the Energy Weapon design sequence (not likely since I'm lazy and usually is more involved than tweaking TNE), or use something already in the rules.

Lasers offer an option for a towed weapon but then do not describe the carriage. In fact, the rule describing the weapon's weight mentions the gun shield but omits any reference to a carriage. It is arguably an error, but slapping a laser on a carriage meant to handle the recoil of a high-velocity gun is neither within the rules nor a proper solution. And let's be clear about what's happening when a CPR gun fires - that recoil dampening system does not make it a recoilless weapon as far as the carriage is concerned; it simply reduces the shock of recoil.

Here's an image of a 155mm howitzer firing:
http://www.youtube.com/watch?v=kb3tfk8dxvU

My guess is, if that were a laser it would not need quite what that 155 is needing.

As to the comments regarding mortar carriages:

http://en.wikipedia.org/wiki/Mortier_120mm_Rayé_Tracté_Modèle_F1

http://en.wikipedia.org/wiki/240_mm_mortar_M240

Please note these very wheeled mortars. A mortar is not towed when it can be readily broken down into man-carryable parts, typically barrel, baseplate, mount and the sight/fire control. When it gets up past a certain size, it's mounted on wheels.

Here's a rather fancy wheeled mortar being used by the Marines:

http://www.youtube.com/watch?v=v5wE1HEtSLQ&feature=related

Fortunately, the idea of a towed direct-fire weapon is pretty absurd by the time lasers become available - combat is too mobile, the crew and weapon are too vulnerable, and it needs to be powered anyway so mounting it on whatever you plan to power it with is easiest. Generally the laser's vehicle mounted or in a fixed installation like a fortification.

Absurd designs are part of the real world so having towed lasers guns is just as likely in Traveller.

 

[snrdg082102]

Hello again Carlobrand,

I can't speak to TNE, and I'd advise caution before mixing game systems.

I'm familiar with most of the Traveller design systems and TNE FF&S is more complex than the simplified Striker design system.

Over the years I've discovered that a lot of the designs posted by individuals mix and match items from other Traveller systems and some have even brought in stuff from other game titles.

"3. Dedicated Support: When committed to dedicated support, the point defense weapon is locked onto a specific friendly vehicle or stand and will follow its movement. Any missiles, rockets, grenades, or indirect fire rounds aimed at the friendly unit or at any target within 10 cm of it [the friendly unit that you locked onto] may be engaged by the point defense weapon in an attempt to destroy them. The weapon makes one attack against indirect fire rounds per turn, and one attack against direct fire rounds per phase, as outlined below."

For example, you're in a vehicle mounting a TL15 RP-X gun and a TL 9 point defense fire control. You're locked onto a friendly tank about a kilometer off, well within direct fire range of your RP-X point defense weapon. There's an APC traveling 8 cm (80 meters) behind the tank you're protecting, and a second following behind - it's 11 cm (110 meters) behind the tank. Suddenly an enemy infantryman pops up from the brush and lets loose an RPG aimed at the first APC. Your point defense weapon detects it, locks on, and fires: you roll a 5 which, with your +3 to hit bonus for the RP-X, is just enough to destroy the RPG round. Unfortunately, the second APC faired less well - it was too far from the tank for your PD system to protect it when a second infantryman stood and fired his RPG.

Note that the design example of the Imperial Marine Grav APC documents a TL 9 PD FC and gives ranges for it that are identical to the ranges of a TL 9 direct fire control.

The ranges should be the same since the difference is that a point defense fire control system is specialized direct fire control system per the details provided in Striker Book 2 page 21.

I now see where Striker Book 2 Point Defense Against Indirect fire got the 6 dice, thanks for the explanation on the dedicated support example.

 

[sabredog]

No, we can't. That's not a logical inference.

Of course we can - CT in particular, and Striker is part of that, is rife with errata and other issues with its rules since a lot of them evolved through supplements, LLBs, and articles in JTAS. HG went through a full rebuild even. And there is more than enough gray as a result to allow for reading between the lines here and there.

The design sequences are distinct; when one depends on another, it is specifically mentioned as depending on that other. Mass Drivers, the immediate prior design sequence, specifically states they're designed using the CPR design system with the noted exceptions. MRLs, the design sequence before that, specifically state they use the CPR system with the noted exceptions. That being the case, you cannot assume a dependence where none is described - nor is that logical, since the gun carriage is far hardier than is needed for a laser.

Lasers offer an option for a towed weapon but then do not describe the carriage. In fact, the rule describing the weapon's weight mentions the gunshield but omits any reference to a carriage. It is arguably an error, but slapping a laser on a carriage meant to handle the recoil of a high-velocity gun is neither within the rules nor a proper solution. And let's be clear about what's happening when a CPR gun fires - that recoil dampening system does not make it a recoilless weapon as far as the carriage is concerned; it simply reduces the shock of recoil.

It's perfectly logical since there is nothing in the rules to say otherwise. You have towed lasers, you have to figure out how much the carriage weighs, and you have nothing to guide you on that other than the rules that came before and after. Energy weapons are far more powerful and have enormous recoil..not to mention show up well after CPR guns have reached their limits in TL, while lasers co-exist for the most part with mass drivers at least. And mass drivers use the same rules for carriages as CPR guns. Yes, yes...I know mass drivers have recoil and lasers don't, but my point is that when there isn't anything the go by then it's safer to use the examples at least prior to the design on the TL tree.

Unless you house-rule. Which can add its own issues to the mix unless done carefully and consistently.

Here's an image of a 155mm howitzer firing:
http://www.youtube.com/watch?v=kb3tfk8dxvU

My guess is, if that were a laser it would not need quite what that 155 is needing.

As to the comments regarding mortar carriages:

http://en.wikipedia.org/wiki/Mortier_120mm_Rayé_Tracté_Modèle_F1

http://en.wikipedia.org/wiki/240_mm_mortar_M240

Please note these very wheeled mortars. A mortar is not towed when it can be readily broken down into man-carryable parts, typically barrel, baseplate, mount and the sight/fire control. When it gets up past a certain size, it's mounted on wheels.

Here's a rather fancy wheeled mortar being used by the Marines:

http://www.youtube.com/watch?v=v5wE1HEtSLQ&feature=related

Yes, pretty aren't they? And thank you, I had no idea how one decided on exactly when wheels might be needed on a mortar. Fascinating.

I understand that howitzers need heavier beams and support when firing than a laser might. And that the Soviets were big fans of wheeled mortars (and HMG's, BTW) even back in the 30's. In fact, if you look at pics from WWI you'll see siege mortars of amazing size on all sorts of wheeled contraptions.

But as for lasers, a ruggedized, battlefield laser might need a heavier carriage than you think, and since CPR gun carriages are based on the weight of the weapon and lasers are pretty light (like a 50mm AT gun is lighter in all ways than a 203 field howitzer?) then the carriage won't be ridiculous for a battlefield weapon. But that's just in my not-so-humble opinion, too. I suppose the argument could be made for spindly laser carriages in the future with developments in materials technology, but Traveller is kind of clunky that way, too, just think of the massive tape-driven computers on ships for an example.

And so....

Fortunately, the idea of a towed direct-fire weapon is pretty absurd by the time lasers become available - combat is too mobile, the crew and weapon are too vulnerable, and it needs to be powered anyway so mounting it on whatever you plan to power it with is easiest. Generally the laser's vehicle mounted or in a fixed installation like a fortification.

....this is, in fact, what I generally have done IMTU since Striker came out. In fact, I doubt if I have a single towed laser in my game anymore since they all tend to be point-defense systems, man-portable, or mounted on vehicles. By TL 13 they lose the instantly-acquired signature and are a little more useful on the battlefield, but by that time things are heading more in the energy weapon direction so lasers are pretty much relegated to point-defense and anti-personnel duty.

 

[aramis]

A towed laser should be a vehicle of its own, with a turret, not a naked weapon on a carriage. IMO.

 

[sabredog]

I agree, it should be, but the rules say they exist. Maybe somewhere in the vastiness of space someone tows a laser but who knows why.

Maybe "towed" means self-contained weapon system, and is to acknowledge that a laser will need to be followed around by a power plant of some kind. And fuel for the power plant. Which is about as close to a vehicle as you'll get if you throw wheels on it and a small drive gear....like those old self-propelled recoilless guns the Army had back in the 50's that looked like my home made go-cart with a gun on top?

Or, since lasers need a lot of power at the lower TL's they become available, and/or because they make ripping point-defense and anti-personnel weapons at those levels, the Striker designers thought they would be best used as part of a complete battery of lasers. One big vehicle to hold the power plant and several towed lasers behind it (in some modular configuration - not just a trail of the things) that would be in a circle around the power supply vehicle. Like a SAM installation. In any case I set them up that way, too, though the lasers are man-portable sized and the power plant vehicle hauls the trailer the lasers are carried in.

 

[SanDragon]

Railgun lasers!

 

[Carlobrand]

Of course we can - CT in particular, and Striker is part of that, is rife with errata and other issues with its rules since a lot of them evolved through supplements, LLBs, and articles in JTAS. ...

Yup, it;s full of errata - and when they publish an errata to Striker towed lasers, we'll have an answer. Stretching logic does not constitute an official answer.

It's perfectly logical since there is nothing in the rules to say otherwise. ...

You didn't seriously go there. We have to do it this way because they didn't say we couldn't??

You have towed lasers, you have to figure out how much the carriage weighs, and you have nothing to guide you on that other than the rules that came before and after. Energy weapons are far more powerful and have enormous recoil..not to mention show up well after CPR guns have reached their limits in TL, while lasers co-exist for the most part with mass drivers at least. And mass drivers use the same rules for carriages as CPR guns. Yes, yes...I know mass drivers have recoil and lasers don't, but my point is that when there isn't anything the go by then it's safer to use the examples at least prior to the design on the TL tree....

When there isn't anything to go by, you admit there isn't anything to go by. At that point, anything that sounds reasonable is acceptable - as a house rule, perhaps even as common convention if enough people agree to it (at which point one hopes the fix gets adopted as official errata). One does not however declare it to be the official way to do things until and unless it is officially embraced as an errata fix.

Inasmuch as there are in fact wheeled mortars, and as they seem to bear the weight of the associated weapon just fine, applying the mortar rules would seem to be an acceptable stop-gap. Though it is strictly speaking a stop-gap. I could also go the route of using the vehicle build rules to build a towed "vehicle" that served as a carriage.

Yes, pretty aren't they? And thank you, I had no idea how one decided on exactly when wheels might be needed on a mortar. Fascinating. ...

Fascinating and beautiful. Wait'll you see the videos on the atomic bomb tests. I have strange tastes.

But as for lasers, a ruggedized, battlefield laser might need a heavier carriage than you think, ...

Might. Might not. No real-world exemplars to go from, and the rules neglect that feature. Ergo the debate - and the uncertainty.

... and since CPR gun carriages are based on the weight of the weapon and lasers are pretty light (like a 50mm AT gun is lighter in all ways than a 203 field howitzer?) then the carriage won't be ridiculous for a battlefield weapon. But that's just in my not-so-humble opinion, too. I suppose the argument could be made for spindly laser carriages in the future with developments in materials technology, ...

A 165 kg carriage under a 660 kg laser is spindly future tech, but a 165 kg carriage under a 660 kg mortar is just fine.

...this is, in fact, what I generally have done IMTU since Striker came out. In fact, I doubt if I have a single towed laser in my game anymore since they all tend to be point-defense systems, man-portable, or mounted on vehicles. By TL 13 they lose the instantly-acquired signature and are a little more useful on the battlefield, but by that time things are heading more in the energy weapon direction so lasers are pretty much relegated to point-defense and anti-personnel duty.

I can't say that I've ever encountered a towed laser. Only honest way I could see it would be some TL 5 society taking some lucky find from a battle with a higher tech force and trying to put it to their own use. In which case, it'd go on whatever carriage they thought to put it on.

Let's do a thought experiment: a towed (and necessarily unmanned, at least inside the unit) laser "vehicle," with controls mounted outside the vehicle. My minimum comes out as follows:

TL 9
Dimensions 1.3m length x 1.25m width x 1.24m height
Front, sides, rear all vertical, no slope
Armor factor 1 all around: 0.13 cm comp. laminate (comp. laminate mainly 'cause my vehicle spreadsheet automatically selects armor by base TL - a weakness in my spreadsheet)
Suspension: wheeled, 0.63m width. Ground pressure 4 t/m^3 (won't ever get mired in soft ground or sand. Might get mired in mud on a roll of 11+)
TL 9 PDFC
Chassis-mounted 10 MW 4-pulse laser
Weight of laser + fire control: 1.16 t
Total weight: 2.075 t, an increase of slightly under 1 ton - a chunk more than a mortar carriage, but quite a lot less than a gun carriage, and as near as I can tell, it's completely "legal".

Increasing suspension to yield a ground pressure of 3t/m^3 requires a slightly larger vehicle and results in a weight of around 2.5 tons.

I could take off side, top and rear armor completely, but it doesn't actually save much.

By example, that Marine Dragon Fire weighs about 2 tons for a 120mm mortar and appears to have a pair of 8" (~40cm) wide wheels.