Stats for GAU-8 Avenger?

[Tomsdad]

Originally Posted by Ulzgoroth

You misunderstand. If you take any Maneuver other than Move or Move and Attack you do not count as controlling the vehicle, as written. There's no skill roll to avoid that because, by definition, there's no one to make the roll.

It's a 1d roll under the vehicle's stability, with 6 as automatic loss of control.

No I understand I'm saying either give big bonuses to the inevitable ensuing out of control roll from "who's at the wheel" (i.e you not really out of control, you have in fact remained at the wheel even while pressing the button). Or just ignore the whole you either controlling or firing in a way that would normally follow an AoA suppressive.

TBH the vehicles rules in Basic are somewhat truncated, and I think as it stands they're more more suited to a driver hanging out the window firing a gun, then a pilot actively lining up an attack run and pulling the trigger on his control stick as he puts the boxes on his HUD over the targets and fires the weapon his plane is built around.

This leaves aside that fact that at different scales suppressive fire means different things for different weapons and their firers.

An A10 pilot flying at a couple of hundred miles an hour firing a rotary cannon with 4000+ rpm firing suppressive fire in order to hose down a column of vehicles is rather different from a solider concentrating on keeping some heads down with his rifle even if in GURPS terms they are the same.

Basically it comes down to what the weapon is designed to do, and how its used. This is what the GAU is designed to do, and if GURPS says doing so has this high chance of ploughing your plane into the ground than I suggest it's more that the Generic suppressive fire rules as they interact with the Generic control of vehicles rules when firing weapons doesn't quite match the specifics of the reality of single pilot ground attack planes vis a vis the A10 the GAU and it ancillary systems.

[panton41]

Originally Posted by Ulzgoroth

I'm not certain it's accurate in any context. Even if it's true for airplanes it's certainly nonsensical for spacecraft (though spacecraft having true fixed guns is also improbable). It would also make it very dangerous for a fighter pilot to attempt to get a missile lock.

The simulator DCS A-10C Warthog displays the behavior Langy mentions. When you pull the trigger to the first detent it turns on the Enhanced Attitude Control System which trims the aircraft to keep the gun pipper on target. Once the mode is activated (by pulling the trigger slightly) the aircraft maintains a flight path to keep the nose of the plane where it was when that trigger detent was pressed. I'm not sure how long it can maintain that but in my experiences in the simulator the aircraft will end up taking on a deeper and deeper dive until the trigger is released.

Considering the simulator is a civilianized version of the U.S. Air National Guard conversion simulator from the A-10A to the A-10C I'm sure it's as accurate as you can get. (It was written by DCS under contract to be the conversion simulator and the company got permission to turn it into a game. I've seen photos of classrooms from ANG bases with computers, Thrustmaster Warthog HOTAS and the military version of this game.)

[Ulzgoroth]

Originally Posted by Tomsdad

No I understand I'm saying either give big bonuses to the inevitable ensuing out of control roll from "who's at the wheel" (i.e you not really out of control, you have in fact remained at the wheel even while pressing the button). Or just ignore the whole you either controlling or firing in a way that would normally follow an AoA suppressive.

You could give a +20 to the 1d6 roll, it doesn't change that you fail on a roll of 6.

Originally Posted by Tomsdad

TBH the vehicles rules in Basic are somewhat truncated, and I think as it stands they're more more suited to a driver hanging out the window firing a gun, then a pilot activating lining up an attack run and pressing the button on his control stick as he puts his boxes on his HUD over the target and fires the weapon his plane is built around.

They are certainly lacking in some respects.

Originally Posted by Tomsdad

This leaves aside that fact that at different scales suppressive fire means different things for different weapons and their firers.

An A10 pilot flying at a couple of hundred miles an hour firing a rotary cannon with 4000+ rpm firing suppressive fire in order to hose down a column of vehicles is rather different from a solider concentrating in keeping some heads down with his rifle even if in GURPS terms they are the same.

Basically it comes down to what the weapon is designed to do, and how it used. This is what the GAU is designed to do, and if GURPS says well if doing so has this high chance of ploughing your plane into the ground than I suggest it's more that the Generic suppressive fire rules as they interact with the Generic control of vehicles rules when firing weapons doesn't quite match the specifics of the reality of single pilot ground attack planes.

...Why do you think that's suppressive fire particularly?

[Tomsdad]

Originally Posted by Ulzgoroth

You could give a +20 to the 1d6 roll, it doesn't change that you fail on a roll of 6.

TBH honest set 1 in 6 results are a bad idea anyway, but to answer you question you fail on result of 6, 1d6+20 wouldn't get many results of 6.

(and before we get into semantics of 'result' vs. 'roll', this is roll that doesn't usually have mods IIRC).

But in reality if I had to use this I'd give a a A10 a pretty good handling score and apply enough negative to the 1d6 roll meaning that unless other factors were involve it wouldn't go out of control.

That or just not use this rule full stop and go with the alternatives I suggested.

Originally Posted by Ulzgoroth

...Why do you think that's suppressive fire particularly?

Because firing lots of rounds into an area attempting to hit large targets within that area is the closest thing in GURPS to what is happening here, the fact that's what GURPS calls suppressive fire is a matter of GURPS definitions.

However your other options are to fire 70 rounds at one target, or to fire several times at different targets, or to fire at one target and hope you missed rounds hit another. etc. I'e it's the best fit, not an exact fit.

Again until we get a more complete set of vehicles (and vehicle combat) rules and or specific rules for attack runs against platoons of vehicles with 70 rounds of 30mm a second, we're going to have accept that a combat system thats really calibrated for skirmishes between individuals may have some interpretive issues when dealing with A10's and convoys and attack runs.

But IMO none that can't solved with a bit of common sense.

If nothing else 'Who's at the wheel' pretty much indicates the original pilot has "left the controls". Only this isn't the case with A10 pilots firing their guns, so I don't think it's an appropriate use of that rule in this situation anyway.

[scc]

Originally Posted by Ulzgoroth

The problem has nothing to do with what hardware you have. (You can Aim anything, it doesn't have to have sights.)

The problem is that "To control his vehicle, the operator must take a Move or Move and Attack maneuver on his turn" (BS467). It goes on to say that if this isn't done the vehicle maintains speed and course, but that's not entirely accurate. Who's at the Wheel?, BS470, indicates a roll every turn to determine whether the vehicle goes out of control.

So technically a pilot could Aim and then All Out Attack with the plane's gun. There'd just be at least a 11/36 chance that the plane would go out of control in those 2 seconds, which would probably be fatal during a low-altitude strafing run.

Easy (If broken) fix, the weapon is spinally mounted, in fact I've heard it said the plane is built around the weapon, thus a Move action can count as a Aim one as well (To Aim the weapon you must also Move the craft)

[Celjabba]

In fact, couldn't you use a piloting skill roll (at a suitable penalty and with associated technique ) as the attack skill ?

Since you cannot stop moving, and aiming the gun involve aiming the aircraft, I think asking for a piloting roll, with success granting aim bonus could work ?

I have little to none Gurps vehicular combat experience, so ... no idea if it would be balanced/workable.

Celjabba

[Figleaf23]

It seems to me that this issue could be improved, if not solved, by adapting the high cyclic rate of fire rules from HT83.

[ColBosch]

I've been out of the GURPS arena for...what, a decade now? So, please excuse me if what I'm about to suggest opens an ancient can of worms.

It would seem that, given no Fourth Edition equivalent of the 3e Vehicles volumes, it might be best to model a solution based on Vehicles, Second Edition until a new, official rule comes down the line. Skills work pretty much the same, right? So, here's what the sidebar on Vehicles 2e, p. 177 has to offer for relevant modifiers:

Weapon firing from air: -1, Firing vehicle has SR 5 or more (I'll give it the benefit of the doubt here; it does have computer assistance): +1, Weapon mounted in body: +2, Vehicle operator firing weapon built into body: Gunner skill limited to vehicle operation skill -3.

So, our base attack is Gunner-1. That sounds reasonable. Page 185 goes on to give rules for Strafing (which seem to be a special action of their own; call it a subset of Move and Attack since no provision is given to use other actions to modify this attack). Nutshelled: the "beaten zone" is 1 yard per Speed/Range modifier, +1 yard per 200 mph of Speed, and is 1 hex wide. Pick a hex and make a Gunner roll, ignoring cover, target size, etc. (because you're aiming at the ground) but do modify for Accuracy, range, and targeting systems. On a critical success, the beaten zone is centered on the desired hex. On a regular success, it scatters randomly by one hex per 200 mph. On a regular failure, it scatters by 5 hexes per Speed/Range modifier. On a critical failure, the GM basically places the beaten zone wherever it would suck most, but no shots can hit the target hex.

You then work out how many rounds hit each hex: at RoF 65 that's 22 in the center hex, with the other 43 distributed evenly among all the other hexes in the beaten zone. Anyone in the beaten zone gets attacked as if by a burst of that number of rounds at a skill of 9 - cover modifiers only.

So, maybe not 100% Fourth Edition compliant, but I don't see why it won't work. (Cue a thousand posts about why it won't work.)

[Tomsdad]

Originally Posted by Figleaf23

It seems to me that this issue could be improved, if not solved, by adapting the high cyclic rate of fire rules from HT83.

That would work well for targeting single targets, but would not help with hitting several targets in a single run (in fact high cyclic ROF doesn't allow suppressive fire IIRC).

Or are you suggesting a free choice between the two to model concentrating on one target or firing in a way to hit several.

[Ulzgoroth]

Originally Posted by Tomsdad

But in reality if I had to use this I'd give a a A10 a pretty good handling score and apply enough negative to the 1d6 roll meaning that unless other factors were involve it wouldn't go out of control.

That or just not use this rule full stop and go with the alternatives I suggested.

I don't think I've seen any well defined rules proposals other than cheating the d6.

Originally Posted by Tomsdad

Because firing lots of rounds into an area attempting to hit large targets within that area is the closest thing in GURPS to what is happening here, the fact that's what GURPS calls suppressive fire is a matter of GURPS definitions.

Not sure it's actually better than Spraying Fire. Actually, it's likely worse than (if slightly easier than) Spraying Fire plus Hitting the 'Wrong' Target.

Originally Posted by Tomsdad

If nothing else 'Who's at the wheel' pretty much indicates the original pilot has "left the controls". Only this isn't the case with A10 pilots firing their guns, so I don't think it's an appropriate use of that rule in this situation anyway.

That implies that the conditions on 470 and 467 are intended to be different. Do you seriously believe that?

(Also, "left the controls" is not an actual quote. What it says is "taken out of action (killed, fell off, abandoned the controls, etc.)")

Originally Posted by scc

Easy (If broken) fix, the weapon is spinally mounted, in fact I've heard it said the plane is built around the weapon, thus a Move action can count as a Aim one as well (To Aim the weapon you must also Move the craft)

Yeah, that seems like a pretty broken fix, though.

Originally Posted by Celjabba

In fact, couldn't you use a piloting skill roll (at a suitable penalty and with associated technique ) as the attack skill ?

Since you cannot stop moving, and aiming the gun involve aiming the aircraft, I think asking for a piloting roll, with success granting aim bonus could work ?

I have little to none Gurps vehicular combat experience, so ... no idea if it would be balanced/workable.

Celjabba

That doesn't actually help with anything. And the existing rule for fixed mounts is to roll against the lower of Gunner or control skill. (BS467)

Originally Posted by Figleaf23

It seems to me that this issue could be improved, if not solved, by adapting the high cyclic rate of fire rules from HT83.

That would let your margin of success generate more hits, but I'm not at all sure that's a real problem here, and it doesn't remotely solve the generalized high-RoF hit rate problem.

Originally Posted by ColBosch

I've been out of the GURPS arena for...what, a decade now? So, please excuse me if what I'm about to suggest opens an ancient can of worms.

It would seem that, given no Fourth Edition equivalent of the 3e Vehicles volumes, it might be best to model a solution based on Vehicles, Second Edition until a new, official rule comes down the line. Skills work pretty much the same, right? So, here's what the sidebar on Vehicles 2e, p. 177 has to offer for relevant modifiers:

Ranged attacks, I gather, have had rather significant changes.