Could someone explain how this vehicle attribute works in SR4?

It will only depress you. It doesn't make sense.

Basically, vehicles all but stop moving 'in combat'; their Speed is basically irrelevant, and their 'Acceleration' is their Movement Rate. In addition to the time dilation effect, it also means you can spin on a dime, etc.

I see the logic of that, and it's still flawed. Someone assumed that "in combat", vehicles drive at a constant speed - imagine a SNES JRPG, if you may, with cars being static on the screen and the road scrolling under them. Acceleration is what allows them to change position - gun it, brake and throw off the attacker's aim or drive up and ram the opponent off the road.

It works fine if everyone is in a vehicle, and probably identical ones; that is, it never works fine. And Chase Combat is totally different, even though that's the closest match for the scenario you mention.

I think the assumption (intended or not) is more that every vehicle comes to a dead stop between every Combat Turn. In that case, Accel-as-Movement 'makes sense'. It works for people, because people more or less go from 0-to-fast instantly (allowing for abstraction).

Funnily enough this very section is what I was reading today. I'm afraid I still have more questions than answers at this point, but it seems like they've made a few flawed assumptions about Vehicle combat and maneuvering. But ignoring that and getting back to how the actual rules work:

Vehicle combat is assumed by the rules as written to be either Tactical Combat or Chase Combat. As I understand them, and some please correct me if I'm off base here, is Tactical Combat is the actual shooting each other while in or around vehicles. Chase Combat really just seems to be maneuvering, jockeying for position as it were. (So obviously in reality all vehicle combat would be a combination of both at varying points.)

A driver who is subscribed to a vehicle (s)he is actually piloting get's the benefit of an increased dice pool, but if they're actually jacked in in some way they then lower the threshold-number of successes needed to do something. Every driving test basically comes down to Attribute (reaction in this case) plus skill plus or minus modifiers-but these modifiers affect two different things. So Handling modifiers actually affect your dice pool; where as terrain, and the "Vehicle Test" (Basically a the complexity of the maneuver you're attempting) affect the threshhold you're looking for.

So if Drive Master has a Reaction of 6, and a Pilot Ground Craft skill of 4 he gets a total of ten dice in his pool. For our example let's assume he cannot subscribe or jack in to keep it simple. He get's a +0 to his handling because he's driving an older model BMW. He's cruising down I5 getting off at Spring street in heavy traffic-So the GM decides that on page 169 of SR4A that this qualifies on the Terrai Test Table as Light, which then increases Drive Master's threshold by one- when he see's that he's being followed by his old arch enemy Drive Apprentice! He decides to floor it, and run the red light pulling a hard right turn onto Spring Street and then slamming on the brakes for a sufdden stop. So the GM decides that this manuever on the page 168 of SR4A chart entitled vehicle Test Threshold Table qualifies as Average which means a base threshold of 2 plus the 1 from the Terrain test for a total of 3.

Drive Master rolls 11 dive, getting 3 hits! (Bad day for him right?) It's not pretty but he does it. Say he had rolled 9 hits his player then could have described something awesome about the scene in some cinematic fashion.

So all in all it's a little more complicated than I'd like-until I memorize all the charts and tables.

It might be a junky mechanic, but who wants to keep vector information about all vehicles in combat?

People with OCD or who are playing Car Wars?

It needn't be that hard, Daylen. Just acknowledge that things keep moving. It's the same as people, except their Speed=Accel (more or less).

SR rule writers occasionally decide to use totally inappropriate words for certain important aspects of the game. I have no idea why they can't afford dictionaries, but it seems that they can't. Velocity and Acceleration are two of the examples that spring to mind.

Alphas under the category "Hyperkinetic".

I think I'm missing the context of "Alphas".

TV show about people who are next evolutionary jumps. Not a bad show, but not much connection to SR.

More like its ok as long as everyone starts at the same initial speed in each turn. And only if everyone is heading in the same direction.

Tactical combat is basically normal SR combat, and mostly it is about drones being mixed in with the other combatants. This because unless your fighting in a parking lot or other open area, getting vehicles mixed in will be difficult (or your basically hovering there, like a combat helicopter providing air support). Chase combat, as the name suggests, is when one party is trying to get away (or somewhere else, like say a bombing run or similar) while the other party is trying to stop them. Hell, even a tank battle plays out pretty much like tactical combat. Only difference is the scale of movement. Rather then moving from rock to rock it is hill to hill...

Yes. If they'd called it something else (maybe just 'Combat Movement Rate'), and stipulated that they're assuming all vehicles stop every turn, then it would at least be consistent and clear. I think issue of drive-by attacks, etc. are more common than that summary implies though, especially with *orbiting* flying drones (and similar things). Under the existing mechanics for 'actions while running' or whatever, it would often make sense for vehicles to do things on the move, but outside of Chase Combat (assuming that domain even has functional rules, because I know many people say they're unplayable).

Meh, i have no problem with it being labeled acceleration. That it is not used as such in the combat section of the rules is a different matter. SR do not handle 100 meter dashes, nor drag races gracefully. Not should we expect it to. The rules are primarily built for in building/courtyard cover to cover battles. If you want military style strafing runs or similar, consider the strategic battle rules in War. Especially the bit about giving aircrafts their own range bands because they will be speeding in and out of the usual combat area.

Again, yes. … But. Drones and vehicles, especially quick and/or flying ones, have been made into a big deal in this edition (for good or ill). It's dumb to model them as constantly stopping to hover… especially because many of them *can't*.

Have they? Didn't notice. Seems to me like they have the same emphasis as they always has...

And if your bringing a non-hover drone to a fight, your doing it wrong (unless you happened to mount the weapons sideways, like on a certain flying artillery base)...

Heh - I was actually just going to suggest Car Wars as an alternative mechanic for working out more detailed vehicle combat.

Like melee, SR4 vehicle combat is an abstraction... and not a very good one. The way the rules are written they seem to assume that, instead of working out the details of a brawl or vehicle gun battle involving the whole table, you'd rather spend your time sitting around watching the hacker make a thousand rolls hacking his way from node to node coordinating his agents and fighting intense cyber battles.

hehe, they assume starcraft combat! Wraith flies up to the tank sooooo fast and STOPS! pew pew.

My group has always used Acceleration as the amount by which a vehicle can change it's speed in a given control action. If a Chrysler-Nissan P-1 has an Accel of 45 (its running rate, assuming the rigger trying to get the hell out of there will be running), it can go from 0-45 in the first turn, 45-90 in the second, and so on (assuming said rigger is getting no extra successes on the test to increase the speed). Slowing down is whatever it used to be, Accel x4 if I'm remembering right. Positioning is handled pretty much the way it is in people-based combat, and we deal with the physics as best we can on the fly, handwaving it where necessary.

My group has never run Chase Combat, so I'm the last person in the world to comment on how it works in play. I like the thresholds for the terrain conditions, but other than that I go more for a cinematic feel. Your mileage, so to speak, may vary.

My favorite moment was a car chase in which a samurai tried to jump out of moving vehicle (we weren't going very fast, maybe 40mpt) because he could "stop faster" at the same time I-- the rigger-- was slamming on the brakes. I stop the car on a dime while the sammie keeps rolling down the center of the street, stopping about halfway between our car and the people we were chasing who had crashed. I don't know why but that really got away with us at the table.

hobgoblin, I just assume that's why those drones exist.

Having read all that... its nice to see that it suffers from the same un-usability as it has in past editions...