[Basic] Skill of the week: Artillery (and Forward Observer)

[sir_pudding]

Originally Posted by Kromm

I'm a bit puzzled at "reintroduce," as I can find no evidence that artillery fire was ever handled by anything but Forward Observer and some sort of weapon skill roll in any edition of GURPS.

Weird. I just checked WWII and CI and you are of course correct. I suppose then I should say "introduce". My apologies.

[Kromm]

Originally Posted by sir_pudding

Yes, okay. Why does a TL4 bombard or mortar still use Artillery if they don't have an observer? Or does it? What happens at TL5, for that matter?

I'm guessing that's the authors' way of saying "these weapons can't respond to moving targets," which is the real Artillery-Gunner distinction, and why Gunner is DX-based (it can lead and plug moving targets).

Originally Posted by sir_pudding

Also in the case you describe, somebody is still translating observer corrections into gun dope, right?

Sure, but because the two PCs in question are almost on top of one another, the observer is seeing where the rounds are hitting, thinking "Hmm, my reflex would be to move my hand like so to hit closer to the target with this dorky little tube that has no sights or bipod," and then saying, "Move your hand like so!" This isn't perfect, but it's probably better than guesswork.

[Kromm]

Originally Posted by sir_pudding

Weird. I just checked WWII and CI and you are of course correct. I suppose then I should say "introduce". My apologies.

No worries. I keep rough stats on claims of "Why did x change between Third Edition and Fourth Edition?" The batting average on these forums is about .200; some 80% of such claims are in error. A lot of folks remember house rules, experimental Roleplayer articles, stuff from APAs, things mentioned on GURPSnet-l, and plain old misreadings as being part of the system when in fact they never were.

[sir_pudding]

Originally Posted by Kromm

I'm guessing that's the authors' way of saying "these weapons can't respond to moving targets," which is the real Artillery-Gunner distinction, and why Gunner is DX-based (it can lead and plug moving targets).

Well you can't really effectively hit moving targets with modern mortars either, except by aiming a point that you expect them to cross and then hitting that (that's one reason why you adjust sheafs for destruction missions, in order to cover a road that you expect a convoy to be on).

On the other hand weren't mechanical artillery pieces used to hit naval targets? Isn't that Artillery skill against a moving target?

Sure, but because the two PCs in question are almost on top of one another, the observer is seeing where the rounds are hitting, thinking "Hmm, my reflex would be to move my hand like so to hit closer to the target with this dorky little tube that has no sights or bipod," and then saying, "Move your hand like so!" This isn't perfect, but it's probably better than guesswork.

I don't think there are any mortars that work like that, pretty much anywhere. You don't do adjusting fires with the M224 in "assault mode", for example, it's just a way to use the weapon as a grenade launcher instead. These weapons are very unstable when fired without bipods (and that's only even possible for the lightest mortars, you'd kill yourself if you tried to fire an 81 without a bipod).

Would you use Artillery if the shooter was using an M-203 or other rifle mounted grenade launcher instead? What you are describing sounds more and more like observed fire with a grenade launcher than a mortar.

Originally Posted by Kromm

No worries. I keep rough stats on claims of "Why did x change between Third Edition and Fourth Edition?" The batting average on these forums is about .200; some 80% of such claims are in error. A lot of folks remember house rules, experimental Roleplayer articles, stuff from APAs, things mentioned on GURPSnet-l, and plain old misreadings as being part of the system when in fact they never were.

Yes, but not a mistake I usually make. :(

[Ulzgoroth]

Originally Posted by Kromm

I'm guessing that's the authors' way of saying "these weapons can't respond to moving targets," which is the real Artillery-Gunner distinction, and why Gunner is DX-based (it can lead and plug moving targets).

That seems redundant given the rules in the "Aiming Fixed-Mount Weapons" box on p80. Though if that's the real distinction it would seem correct anyway.

However, that being the real distinction seems bizarre, considering that every item on the list except maybe a catapult could be used to hit a moving target (and Guided Missile and Torpedo in particular usually are). They all take a certain amount of travel time, but so do all non-superscience missile weapons...

[benz72]

Originally Posted by Ulzgoroth

Possibly. On the other hand, if you do make that Artillery, then what about grenade launchers and low-velocity cannon? At what angle of elevation does the skill switch?

Also, when you get down to it...do you think it's an IQ/A skill?

At least from my NGFS based perspective, it isn't really about the angle but rahter about the method of aiming.

I'd throw the gunner/artillery dividing line at the single user/mulit user point.
Make the FO/artillery skill pair a team and make Gunner a self contained skill.

Take the following cases:
On a DD there was (somewhat crappy) device known as a target designation transmitter (TDT). It was very basically a set of binoculars with servo drivers that could slave a 5" gun to the pointer. It was operated by a single man looking through a device and pulling a trigger. I would make this a Gunner skill. To fire the exact same mount at the exact same target using a FO and a gunnery liaison officer/CIC combat team I would make it a pair of rolls (FO & Artillery). It really has nothing to do with the size of the weapon or the angle of fire.

With that distinction I can easily see many weapons using either skill depending on firing mode. Similarly I can see attaching penalties to some guner skill rolls for defilade fire. This penalty can vary based on the difficulty of using the weapon in that mode.

Also look at the new CIWS 1B http://en.wikipedia.org/wiki/Phalanx_CIWS which allows remote engagement from CIC through a camera. I'd call this a Gunner skill roll regardless of the other specifics of the situation.

I have no idea about mortars but in my mind I would expect them to be used almost exclusively as a FO/Artillery weapon and only at some kind of odd default direct (enfilade) aiming with the Gunner skill (probably at default).
Again, it has nothing to do with the angle of the SHOT but rather to do with the method of AIMING.

To apply this to ancient siege weaponry, If I am making adjustments to my trebuchet with calculations and a report or observation of previous impacts roll FO/Artillery (possibly from the same person... the accuracy of the corrections is inherently limited by the acciracy of the impact information).
If my trebuchet operator has somehow calibrated a device to let him put his eyes in line with the target and activate the mechanism then it would be a Gunnery roll.

[Not another shrubbery]

Regarding the Sotw: Another example of skills that have only seen 'color' duty in our games, although there have been occasions where they've been useful for associated NPCs.

Originally Posted by sir_pudding

Yes, but not a mistake I usually make. :(

As someone who has visited that address more than once, I'd say it's not such a bad place... gets a bit crowded sometimes, though.

"And bad mistakes - I've made a few."

[Ulzgoroth]

Originally Posted by benz72

Also look at the new CIWS 1B http://en.wikipedia.org/wiki/Phalanx_CIWS which allows remote engagement from CIC through a camera. I'd call this a Gunner skill roll regardless of the angle.

...Nobody uses a CIWS for indirect fire, do they? When we talk about 'high angle' fire we're referring to shooting at a high angle and having the shell fall back down, not pointing your gun up because that's where the target is.

Originally Posted by benz72

To apply this to ancient siege weaponry, If I am making adjustments to my trebuchet with calculations and a report or observation of previous impacts roll FO/Artillery (possibly from the same person... the accuracy of the corrections is inherently limited by the acciracy of the impact information).
If my trebuchet operator has somehow calibrated a device to let him put his eyes in line with the target and activate the mechanism then it would be a Gunnery roll.

As far as I can see this is exactly what I previously suggested, for multiple posts.

[benz72]

Originally Posted by Ulzgoroth

...Nobody uses a CIWS for indirect fire, do they? When we talk about 'high angle' fire we're referring to shooting at a high angle and having the shell fall back down, not pointing your gun up because that's where the target is.

Yes, I should have been more clear. I was specifically referring to the observer and aimer being the same person in that scenario and threw in the angle reference as a way to emphasize that it wouldn't matter whatever it was. It was a poor choice of words. Thanks for pointing out that it causes confusion.

As far as I can see this is exactly what I previously suggested, for multiple posts.

Yes, I'm only adding a specific perspective that corroborates your opinion. I'm not arguing with you.

[Ulzgoroth]

Originally Posted by benz72

Yes, I'm only adding a specific perspective that corroborates your opinion. I'm not arguing with you.

Okay, sorry. I've made that mistake a few times recently, I may need to recalibrate.