High speed crashes

[zenten]

How much damage would a head on colision do, with both cars moving fast?  Would the drive roll be an all or nothing thing, or would it lower the damage by some amount?

I'm thinking of a situation where a BCV will have a Renfield jump the yellow line while the PCs are driving to make an ambush easier.

[tetrasodium]

How much damage would a head on colision do, with both cars moving fast?  Would the drive roll be an all or nothing thing, or would it lower the damage by some amount?

I'm thinking of a situation where a BCV will have a Renfield jump the yellow line while the PCs are driving to make an ambush easier.

I was in a similar but different situation a couple years back (guy ran redlight, plowed into the engine area of ,y car & spun me like a top while I was going 45ish & him whatever he was doing)... all those movies where they show the hero/villain  cranking the steering wheel around while their car is doing acrobatics are bunk.  I hit the seatbelt so hard/fast that I had seatbelt burns and it cut into my skinthrough my shirt.  the bruising was crazy, I gained about 10-20 or so pounds from swelling over the next couple days and had a big /purply-red area around my belly where I hit it hardest. it took me about two weeks before I healed enough to be able to just sit up in bed wityhout having to use my arms to push me up.  trying to do so without the arms was kinda like the morning after doing a zillion situps/crunches where you just can't get the muscles to do more than tell you to f'off and scream at your brain for making them try to move.  Immediately after the accident both me & the other driver were kinda shaking & wobbly from the shock of the accident & seatbelt trauma.  a head-on collision would be even worse because you have the speed f both vehicles adding to each other's speeds for purposes of the impact  force 45mph+45mph head on is the same as 90mph against a wall capable of withstanding the impact (I got spun like a top so didn't get the full force)

I thought I got out of the car as soon as I stopped, the cops were arriving as I stumbled out of my car  because the airbag dust was coming out of the vents & I thought the car was on fire. Had I realized what it was at the time, I would have fucking sat right there and waited to stop shaking like a chihuahua.

Needless to say, for the TL;DR version: for a head on collision, you are probably going to be there till EMS or someone else helps you out if you are human.  if you are not buckled in, you are going out the freaking window & laying there until someone scrapes you into a plastic bag.... don't go for realism & skip it altogether if your players are kids or impressionable.  Maybe go with speeding motorcycle tbones car like so
http://www.liveleak.com/view?i=db5_1249698859

[Selrach]

Consequential contest Driving vs Athletics of Renfield (if the Renfield is trying to hit the car) with the result being Moderate consequences and the car slowing down and/or stopping? As for what happens to the Renfield that's up to you, could be anywhere to consequences to just squish. It's a bit harsh but as tetrasodium  said car crashes are serious business.

[The Mighty Buzzard]

a head-on collision would be even worse because you have the speed f both vehicles adding to each other's speeds for purposes of the impact  force 45mph+45mph head on is the same as 90mph against a wall capable of withstanding the impact (I got spun like a top so didn't get the full force)

The Mythbusters did exactly that last season because they made the same mistake and some physics hobbyists called them on it.  Result: 45car vs 45car = 45car vs wall.

[tetrasodium]

The Mythbusters did exactly that last season because they made the same mistake and some physics hobbyists called them on it.  Result: 45car vs 45car = 45car vs wall.

I just looked up the episode& apparently we are both wrong.  the =45 vrswallis only accurate if both cars are the same weight, if they are it's true because the impact is spread over a larger area (but they are still pretty boned as human passengers  & scraped off the ground if not buckled in).  if it was a tank like a Buick/Cadillac vrs a little modern compact commuter  car, that compact car is freaking screwed 

[sinker]

To be honest Zenten, I would think less about stress and more about story. How do you want this to feel to the PCs? Obviously I'm assuming that you don't want realism in this case. It would be a pretty poor scene if they were simply killed (or captured, whatever) while they are sitting there stunned and struggling to breathe. I assume that you want your PCs to jump out of the wreck with a few cuts and bruises, ready(ish) for a tussle. The best way to do that is of course with aspects.

The consequential contest is a decent idea that would allow the driver to mitigate the damage (the better their roll, the less the consequence) but it's not likely to accomplish what you want (I.E. the PC driver is likely to be much better than the renfield). I might treat it as a cross between a simple action and a consequential contest, assigning a difficulty to avoiding the accident and then dealing a consequence based on how much the roll failed by.

Something to consider though is that this only effects the driver. Any passengers in the car haven't rolled, so you don't have anything to base a consequence on, plus it kinda sucks when you're playing and the GM goes "Take a consequence that is not a result of anything you did and that you can't avoid." I suppose you could allow the passengers to make an athletics or endurance roll (?) in a similar manner to see what kind of consequence they escape with. I dunno.

Finally something else that you can (and I would say definitely should) do is start the conflict with some aspects referring to the wreck. Then compel the players any time you feel that they should be limited  by those circumstances.

[ARedthorn]

Sinker's right- there's nothing wrong with fudging for the sake of story. That said- while there are no rules for car crash severity- there are rules for falling... namely, every 10 feet of falling = 5 stress (unavoidable, ie, always hits- but reduced by armor and rolling with it helps MARGINALLY).

Doing a little math (I actually am a rocket scientist. Well, astrophysicist- close enough)... ignoring terminal velocity:
-a 10 foot fall has you going about 17mph. 5 stress.
-a 20 foot fall has you going about 24mph. 10 stress.
-a 30 foot fall has you going about 30mph. 15 stress.
-a 40 foot fall has you going about 35mph. 20 stress.
-a 50 foot fall has you going about 39mph. 25 stress.
-a 60 foot fall has you going about 42mph. 30 stress.
-a 70 foot fall has you going about 46mph. 35 stress.
-a 80 foot fall has you going about 49mph. 40 stress.
-a 90 foot fall has you going about 52mph. 45 stress.
-a 100 foot fall has you going about 55mph. 50 stress.
-a 120 foot fall has you going about 60mph. 60 stress.
-a 150 foot fall has you going about 67mph. 75 stress.
-a 200 foot fall has you going about 77mph. 100 stress.
-a 250 foot fall has you going about 86mph. 125 stress.
-a 300 foot fall has you going about 95mph. 150 stress.
-a 350 foot fall has you going about 102mph. 175 stress.
-a 400 foot fall has you going about 109mph. 200 stress.
-a 450 foot fall has you going about 116mph. 225 stress.
-a 500 foot fall has you going about 122mph. 250 stress.

It gets fairly out of hand from there. Course- this is a good benchmark for what happens if a car hits a pedestrian (60mph = 60 stress, mostly going to the person = instant pudding).

For vehicle on vehicle, it needs some tweaking. A lot of that energy gets wasted in the form of movement (it's rare that both cars just stop in their tracks- usually they skid off eachother and bounce around a lot)... and of course, most of it gets absorbed by the car itself rather than going directly to the passengers... and the equivalent of "rolling with it" would be trying to steer away from the wreck at the last second, so it only provides a glancing blow.

Short form: I'd let the driver(s) roll to reduce (or increase, his choice) the damage... say, +2 stress per +1 on the roll?
Then I'd assume that any small vehicle is going to take at least 1/2 of the damage dealt, with the rest going to passengers... with most taking more like 3/4 of it.
The remaining damage occurs as a zone effect to all passengers (rather than being split up)... each safety feature is a taggable aspect they can use to reduce the damage (seatbelts, harnesses, helmets, body armor, airbags, roll-bars/cages, professionally armored vehicle, etc) IF it's being used.

Anyone in a 60mph head-on collision is looking at taking 45 stress to their vehicle, and 15 stress themselves if they aren't wearing their seatbelt. More than enough to kill, but also survivable with serious injury.


As for the mythbusters- the mistake they made was that they would've been right if they'd been talking about the total energy of the system... but the way that energy gets split up between objects of same or differing mass threw them.
Total damage should be based off the total speed of both vehicles combined, then split up between the 2 vehicles (which is why the mythbusters got it wrong- they were right that a head-on-head 60mph + 60mph collision had 2ce energy as a 60mph vs wall.... but that energy is split up because it also has 2ce the mass to affect)... if one car is a lot lighter than the other, then it'll get bounced around more... but most of the time, if both vehicles are fairly similar in mass, just split it evenly. (In game: Motorcycles and semi's involved? Fudge it one way or the other as appropriate).

[Tedronai]

Course- this is a good benchmark for what happens if a car hits a pedestrian (60mph = 60 stress, mostly going to the person = instant pudding).

What happens when a car hits a pedestrian is already addressed in the rules.  A 'mack truck' at high speed is a weapon:5 attack.  Which basically does mean 'instant pudding' for most mooks.

[ARedthorn]

Then, for whatever reason, falling seems to be WAY THE HELL LETHAL in this game, relative to anything else that should be equivalent.... weird.

[Tedronai]

Yep.

[sinker]

Yeah I really hate the fall damage in this game. I figure if you're going to do it that way you might as well treat it as a plot device. People fall to their death when they fall to their death and they don't when they don't.

[Sanctaphrax]

It's really weird. The game is normally so abstract, but it has specific rules for falling.

And they are terrible.

Maybe that's why the book seems so apologetic about providing them.

[TheMouse]

It's really weird. The game is normally so abstract, but it has specific rules for falling.

And they are terrible.

Maybe that's why the book seems so apologetic about providing them.

They feel to me sort of like they were glued on.

Me, I'd just use Consequential rolls. Throw together some sort of guesstimated correlation between distance and damage, roll, and move on. It seems a lot more applicable than saying, "Well, you're falling 50 feet, so you're taking 25 Stress. I, uh, hope you have insurance."

I mean, I know that in the real world, an uncontrolled fall of 50 feet just normally kills a dude. But so does getting hit by a big truck going 60 MPH. Why one is 25 Stress and the other is weapon:5, I don't know beyond guessing that the damage rules were an afterthought.

(Also, my spell checker recognizes, "Guesstimate.")

[sinker]

I mean, I know that in the real world, an uncontrolled fall of 50 feet just normally kills a dude.

My father fell five stories and managed to simply loose all the cartilage in one knee (he's about half an inch shorter in one leg now, which oddly enough is the source of my knee problems). He was a gymnast as a youth though, so maybe he just rolled really well. 

[ARedthorn]

Falls are ridiculously unreliable. You can fall 2 feet and die if you land just wrong. You can fall 100+ feet (onto a rocky surface, even) and survive if you fall just right. The exceptions don't happen often, but they do happen.
That's why most systems I've seen run it on a die-roll, to keep it random. Flat-growth systems are nice and simple, but never satisfying or realistic, and always run into these problems.
Personally, I'd tone the fall system down, and tone collisions up until they met somewhere in the middle, and be pretty happy with it, but I'd say best bet is to go w/ concessions all the time, every time.