Model S Car Crash Help for After Action Review

[David99]

From what you wrote, it seems it's just black ice. Nothing you could have done different and nothing that the car caused. I have had a few situations with my Model S that were similar. I hit some black ice patches and the car went out of control. Luckily I didn't crash.

As you said, it's just the laws of physics. No friction/traction on an icy road means the car will go follow it's momentum. Winter tires make little to no difference on black ice. The only thing that helps is slowing down. The other thing as McRat suggested is practicing these situations. It is our normal reaction to panic and floor the brakes when we are about to slide off the road or into an object or we try to yank the wheel and swerve around it. Both can make things worse. Only training and practicing these situations can help to unlearn that got reaction and instead do something that can actually prevent a crash or at least limit the damage.

 

[murphyS90D]

Read the reviews on Michelin X-ICE tires and their competition. And yes you need them on all 4 wheels even if you have a RWD car. A RWD car has all wheel braking.

 

[rstefani11]

From what you wrote, it seems it's just black ice. Nothing you could have done different and nothing that the car caused. I have had a few situations with my Model S that were similar. I hit some black ice patches and the car went out of control. Luckily I didn't crash.

As you said, it's just the laws of physics. No friction/traction on an icy road means the car will go follow it's momentum. Winter tires make little to no difference on black ice. The only thing that helps is slowing down. The other thing as McRat suggested is practicing these situations. It is our normal reaction to panic and floor the brakes when we are about to slide off the road or into an object or we try to yank the wheel and swerve around it. Both can make things worse. Only training and practicing these situations can help to unlearn that got reaction and instead do something that can actually prevent a crash or at least limit the damage.

Thanks David!

 

[rstefani11]

Read the reviews on Michelin X-ICE tires and their competition. And yes you need them on all 4 wheels even if you have a RWD car. A RWD car has all wheel braking.

Agreed, they seem like great tires for snow going forward. All things considered though, I might just rely on public/hotel transportation if I go skiing again!

 

[chillaban]

From my driving experience, if any wheelslip happens while regenerating, the "ESP2" (all Teslas made since dual motors) cars will immediately cut out regen, which could feel like an acceleration surge.

If that happened during your conditions, it seems like you hit a slippery patch underneath and that would've been doom no matter what. Even snow tires don't magically provide traction if it's black ice underneath, though everyone is absolutely right in that snow tires or at least the first 10-20k miles of treadwear on a UHP all season is superior to standard all-seasons.

 

[croman]

Read the reviews on Michelin X-ICE tires and their competition. And yes you need them on all 4 wheels even if you have a RWD car. A RWD car has all wheel braking.

I have these tires on a set of Rial Luganos. My car still has them (put them on during my annual service in November -- Tesla will put on winter wheels (or take off winter wheels and put on your summer/all-season) for no charge during annual service). In 2-3 weeks I can take off my winter tires and enjoy only the rarest random snow after April in Chicago.

FYI, my winter tires provide excellent traction even with ice. Studded winter tires might be even better for some vehicles but I don't like the impact on the road and environment, so I chose studless.

 

[Kandiru]

Glad you are OK.
1. Snow tires in winter, ultra high performance summer tires outside of it. CR had a special, all seasons double the braking distance on ice and snow.
2. Winter driving: no AC just butt warmers. Leaving to anywhere an hour away with less than 100mi is suicide in winter.
3. Battery low, cut speed in half, flashers on for safety. You will double your range.

 

[rstefani11]

From my driving experience, if any wheelslip happens while regenerating, the "ESP2" (all Teslas made since dual motors) cars will immediately cut out regen, which could feel like an acceleration surge.

If that happened during your conditions, it seems like you hit a slippery patch underneath and that would've been doom no matter what. Even snow tires don't magically provide traction if it's black ice underneath, though everyone is absolutely right in that snow tires or at least the first 10-20k miles of treadwear on a UHP all season is superior to standard all-seasons.

YES! That is exactly what the experience was on the 'accel surge'. Thanks Chillaban, appreciated your insight

 

[rstefani11]

Glad you are OK.
1. Snow tires in winter, ultra high performance summer tires outside of it. CR had a special, all seasons double the braking distance on ice and snow.
2. Winter driving: no AC just butt warmers. Leaving to anywhere an hour away with less than 100mi is suicide in winter.
3. Battery low, cut speed in half, flashers on for safety. You will double your range.

Thanks Kandiru, appreciate the feedback

 

[McSaggler]

Just curious, did your car alert you that regenerative braking was limited due to cold weather?

 

[paixim]

Did you have a chance to check if your tires were michelin pilot super sport (Summer) or pilot sport A/S (all season)? We have been going on ski trips with Michelin MXM4 (all season) and seriously considering getting a set of dedicated snow tires.

 

[Snobun]

So sorry this happened to your car! I am originally from CA, then moved to MI for a few years. My husband and I survived 5 brutal, snowy MI winter in our RWD BMW with all season tires. We feel the key to our survival was good all season tires every winter AND driving slow - under 20mph, and that’s on flat land. When we go on ski trips in CO/Tahoe/Mammoth, we drive even slower, especially on slopes/around curves eventhough we now have an AWD SUV just for skiing. Once your car started sliding, there is nothing much you could do. We also noticed that having less snow on the ground (1/2” or dusting) is actually worse than having inches so that calls for more caution. We only have our S for a few months and have not taken it on snow yet so I cannot comment on how the Tesla can/should handle in the situation, but I’d say going 25-30mph downhill + curve was a bit too fast. Again, sorry to hear about your accident but glad that you walked away from it and can learn to do better next time! BTW, I LOVE Mammoth!

 

[brianp6621]

One thing I haven't seen people mention is that the car seemed to have "died". Is that due to the battery being completely depleted early than expected in the cold weather? In that case I think an additional cause here is that going into a harsh climate like that there should have been extra precautions taken to make sure there was more range left in the batteries to prevent being stranded/having the car completely die on you as it seems to have. Cold temperatures, significant mountain climbs, and extra use of the heater in cold conditions will all increase battery draw.

 

[rstefani11]

Just curious, did your car alert you that regenerative braking was limited due to cold weather?

No, it only gave an alert that battery power would reduce more quickly because of cold weather. At 55 mile range that was about 17% remaining power with 315 'optimal' range. It would have been a great notification. I know now based on others feedback to turn it off in the snow to minimize the risk of the 'surge' in acceleration that I felt when the car must have slipped on the regen

 

[rstefani11]

One thing I haven't seen people mention is that the car seemed to have "died". Is that due to the battery being completely depleted early than expected in the cold weather? In that case I think an additional cause here is that going into a harsh climate like that there should have been extra precautions taken to make sure there was more range left in the batteries to prevent being stranded/having the car completely die on you as it seems to have. Cold temperatures, significant mountain climbs, and extra use of the heater in cold conditions will all increase battery draw.

Before all the kind folks in this thread provided feedback I believed that to be the case as well... the feeling of the car shutting down, but it did have 17% power (approx 55 miles remaining)... distance between main lodge and village is 4 miles...but through the windy roads. The regen cutting out, feeling the surge of accel because it cutout and bad luck with black ice, no snow tires... it all makes sense.

 

[rstefani11]

So sorry this happened to your car! I am originally from CA, then moved to MI for a few years. My husband and I survived 5 brutal, snowy MI winter in our RWD BMW with all season tires. We feel the key to our survival was good all season tires every winter AND driving slow - under 20mph, and that’s on flat land. When we go on ski trips in CO/Tahoe/Mammoth, we drive even slower, especially on slopes/around curves eventhough we now have an AWD SUV just for skiing. Once your car started sliding, there is nothing much you could do. We also noticed that having less snow on the ground (1/2” or dusting) is actually worse than having inches so that calls for more caution. We only have our S for a few months and have not taken it on snow yet so I cannot comment on how the Tesla can/should handle in the situation, but I’d say going 25-30mph downhill + curve was a bit too fast. Again, sorry to hear about your accident but glad that you walked away from it and can learn to do better next time! BTW, I LOVE Mammoth!

Thanks, yep, I think it did not help going 25-30...then when the regen brakes stopped, the 'surge' and the impending doom for the car was inevitable with all the other previous issues (no true snow tires, etc). I haven't lived in Chicago for 18 years, so I was absolutely overconfident in driving in snow even if it was just 1/2 inch, and had not driven on icy roads in a long time. Preventable, and I'm just glad I didn't hurt the cop

 

[rstefani11]

Did you have a chance to check if your tires were michelin pilot super sport (Summer) or pilot sport A/S (all season)? We have been going on ski trips with Michelin MXM4 (all season) and seriously considering getting a set of dedicated snow tires.

The body shop is over an hour away and I completely forgot when I went to see it... Pulling out personal belongings. It was a miserable site to see the car in such bad shape. It was damaged as well during the tow. The good news is that it 'seems' like the car is repairable from the body shop service manager and so I will be able to report back. It's going to be a long road... predictions right now are 4 months for it to be ready. Dang my bad luck. At least something to look forward to...

 

[bhzmark]

I felt regenerative braking stop, steering wheel became unresponsive--tried turning left but no response. Brakes were also unresponsive and the car slid sideways down the hill where it then crashed into a post

One possibility, that I experienced and almost had the same result as you, was that on an icy road, the ABS doesn't quite work as it should and wheels totally lock up and you are just sliding like a hockey puck. Perhaps since all 4 tires lock up so easily, the ABS just thinks you are standing still with the brakes on. When the wheels are locked up, the steering wheel does no good at all, and the tendency is to just push the brakes harder which doesn't work.

My solution was to totally release the brakes and because of regen put the car in neutral. This gave me some rotation back to the tires and I was able to get some steerage back and barely steer away from the parked cars that were lining the icy hilly road I was on. The car had to go downhill faster than was ideal, but I had to give up the brakes in order to get the steering back.

I used to think all seasons were ok around town and only needed snow tires if going up a ski mountain or similar, but that changed my mind.

 

[rstefani11]

One possibility, that I experienced and almost had the same result as you, was that on an icy road, the ABS doesn't quite work as it should and wheels totally lock up and you are just sliding like a hockey puck. Perhaps since all 4 tires lock up so easily, the ABS just thinks you are standing still with the brakes on. When the wheels are locked up, the steering wheel does no good at all, and the tendency is to just push the brakes harder which doesn't work.

My solution was to totally release the brakes and because of regen put the car in neutral. This gave me some rotation back to the tires and I was able to get some steerage back and barely steer away from the parked cars that were lining the icy hilly road I was on. The car had to go downhill faster than was ideal, but I had to give up the brakes in order to get the steering back.

I used to think all seasons were ok around town and only needed snow tires if going up a ski mountain or similar, but that changed my mind.

Great feedback Bhzmark. I think you are right about the ABS. I genuinely can't remember now whether I had foot on brake the entire slide or if I let it go. One of the earlier feedbacks above was to 'not be a passenger' and engage the vehicle as best I can. I wonder if Tesla can offer a 'driver's course or performance course' given the unique capabilities of the vehicle. I did something like that with a BMW M3 in Spartanburg SC. It was helpful at the time. Just hoping my car can get fixed so I have something to look forward to. I'm supposed to find out tomorrow what the 'body shop' adjustment is (compared to the initial insurance adjustment). If it's declared totaled I'm going to be very depressed.