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Black ice on the road and my Model S

Discussion in 'Model S: Driving Dynamics' started by ElectricAvenue, Nov 24, 2013.

  1. ElectricAvenue

    Joined:
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    Nashua NH
    I took a trip from the beach in NH to southern NH yesterday evening. Left the restaurant after dark and found it had started to lightly snow with strong winds, outdoor temps were 32 degrees.
    On the highway I was going a little above the speed limit and saw emergency vehicles on the other side of the highway at 4-5 separate locations, then started to see cars on the side of the road and it still hadn’t occurred to me these cars that had slid off the road. Only after I came to a toll booth did I realize there was black ice on the road ( I am a very careful driver and being the first snow shower of the season it took me some time to realize how dangerous the conditions were.)
    Well the first curve in the highway after the toll booth came 3 stationary cars on my side of the road that were on the hard shoulder with their hazards on. There was one car in front of me travelling forwards and slowing down, I moved into the fast last lane and that is when the rear end started to fishtail, I steered into the skid the back end caught and then fishtailed the other way. I know I didn’t touch the brakes but I don’t know if regen turned on when I let off the accelerator because it happened so quickly.
    It was definitely black ice, 3 cars were unable to recover and I was in the fast lane.
    I don’t know if I would have been safe in my previous car (probably would have been) but I was definitely impressed with the way the Model S handled, especially being the first rear wheel drive car I have driven. I continued home safely.

    By the time I got home I past about 15-20 cars that were off the road.

    Funny thing is I have a set of winter wheels and tires sitting in the garage waiting to be installed by Tesla SC in a couple of weeks.
    I am running the OEM 19” right now.

    Been careful of that first snow!
     
  2. SCW-Greg

    SCW-Greg Active Member

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    Thanks for sharing, and to be alert!

    Always have wondered how instant regen would affect knee-jerk reactions that often happen in these scenarios. Sounds like a white knuckled drive none-the-less.

    I just don't plan on putting my a Model S into these possible weather conditions... if I can at all help it.

    Although, I suppose this is the safest vehicle to be in, in the most treacherous of conditions.
     
  3. Doug_G

    Doug_G Lead Moderator

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    One lucky thing about regen is that braking from the rear tends to pull the car into a straight line. But do be careful to feather off the gas pedal. If you really start to lose it plant the friction brakes so the ABS engages, that will both slow the car and maintain some steering control.
     
  4. ElectricAvenue

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    Doug, I did some 'testing' on the roads when I realized there was black ice after I saw the 3 cars, that included pulling off the accelerator fully to see if the car skidded from the rear end and you are right, the ABS kicked in and the car kept straight. I know I did not feel the ABS kick in when I passed the 3 cars, therefore I must not have pulled off the accelerator too much!!! Thanks.
     
  5. skdave

    skdave Member

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    I do not plan on driving in this type of conditions unless it sneaks up on me. I have a H2 Hummer for playing in the snow and ice.
     
  6. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    I'll have a good test tomorrow because it appears as if it will be an ice day.
     
  7. Doug_G

    Doug_G Lead Moderator

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    In my experience, real black ice usually sneaks up on you, especially at night. It's totally black, and crazy slippery. Many years ago I did multiple 360's on a highway ramp, had no idea it was coming until the back kicked out. By some miracle I came out of the spin still on the ramp, but going backwards at ~ 70 kph. Managed to stop safely. These days I pay very close attention when the weather is conducive!
     
  8. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    When I lived in Vancouver it was almost impossible to tell when there was black ice and when the streets were just wet with rain. Here in Texas, it's just plain ice but there is advance warning and on an ice day it's everywhere--no guessing required.
     
  9. ChadS

    ChadS Petroleum is for sissies

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    I agree it's best to feather off the accelerator, but some of us were trained to pull off the accelerator quickly when anything slides. I did that last winter when I hit a surprise slippery spot (frozen fog, I think - the road LOOKED dry) in my Model S, and I think it made things worse as the rear went back and forth quite a ways.

    For now, I turn regen down if I think I could hit a slippery spot.
     
  10. Doug_G

    Doug_G Lead Moderator

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    Wow, that sounds like really bad training. You should pretty much never do anything abruptly in a car, especially when you're at the limit of grip.
     
  11. patp

    patp Member

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    Last winter I've set regen to low for winter driving. I think it's safer that way.
     
  12. mknox

    mknox Well-Known Member

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    True, but sometimes easier said than done. Idiots around here like to jump into your front buffer zone and slam on their brakes for some reason. Actually, I think it's because they rush into the opening and have to slam on their own brakes to keep from hitting the car in front. In any event, you pretty much have to get off the gas and on to the brakes asap.
     
  13. ChadS

    ChadS Petroleum is for sissies

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    I agree it was bad training; but it's the training I got, and more to the point exactly what I did when I felt something slip. I will try to retrain myself...but I'm still keeping regen on low when it's freezing out. Regardless of what I do, it's helpful if the car doesn't make sudden moves in slippery conditions either.

    At least I've got tires that work in cold weather. A lot of owners in this area run summer tires all year round because freezing weather is rare, and they figure they can stay lucky.
     
  14. Alysashley79

    Alysashley79 Member

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    At least I've got tires that work in cold weather. A lot of owners in this area run summer tires all year round because freezing weather is rare, and they figure they can stay lucky.[/QUOTE]

    +1
    I live by issaquah chads but at about 2100' elevation I as we'll have good winter tires on ALL my vehicles and carry chains just in case but completely agree with you. I'm usually pulling my neighbor out of the ditch for this very reason! And we typically get around FEET of snow
     
  15. neroden

    neroden Happy Model S Owner

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    Shortly after I first got my Model S, last March, I was going too fast (45 mph) on a steep downhill slope on a country road and hit a patch of black ice (with all-weathers on). The *front* end started to fishtail.

    I hit the brakes and the ABS stopped me within 1000 feet. I didn't even leave my lane.

    The car is very good on ice.
     
  16. EdA

    EdA Model S P-2540

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    I was shocked by the pellets of snow falling when I left work last night.
    I got my snow tires put on a few weeks ago and I took things slowly but the snows do give you a lot of confidence!
    Don't think we had the exact black ice and I took the back roads since the highways were jammed and didn't
    encounter cars off the road.
     
  17. wcalvin

    wcalvin Member

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    There is a diagram on page 61 of the Best Ever book on how the Electronic Stability Control works. It compares desired and actual direction of travel. Usually the steering wheel angle and the car's actual direction agree. But when they don't, the ESC adjusts individual brakes (and even engine speed) to correct it. Sounds like it doesn't require your foot on the brake pedal. Anyone know more?
     
  18. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Vehicle stability control prevents doughnuts when turning. The 2004 Prius has this, and boy is it great for ice days. (Haven't had a chance to try the Model S' yet--our ice day that was supposed to happen on Monday fizzled out.) If I try really hard (on an empty street) I can get the car to go sideways and it immediately straightens out.

    This isn't the same thing as ABS which is about stopping. VSC and ABS complement each other but they do different jobs.
     
  19. jaw

    jaw New Member

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    Sipped tires have innumerable cuts to add traction in all conditions. The added grip is very noticeable, rain or snow. Discount Tire and other tire shops will make these sipe cuts at a small cost.
     
  20. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Tire manufacturers spend a great deal of money developing their tread and sipe patterns. Using an aftermarket sipe cutter is a bad idea (although it comes around about once every ten years or so). Proper tires such as Michelin Xce xi3 or Nokian Hakkapeliitta R2 will perform far better than some amateur sipe cutting.
     

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