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Icy/snowy mountain highways following how close?

What are the vehicle to vehicle distance ( V2V ) behaviors of drivers in your ski

region when driving on mountain highways when there are enough vehicles on a

road that cars back up end to end in a chain and road surfaces contain variable amounts

of snow and ice?  In other words not when such highway road surfaces are either dry or

simply wet but rather contain ice and or snow?

Of course when vehicles on slippery road surfaces follow too closely or

tailgate, if a leading vehicle brakes there is a possibility a following

vehicle might cause a rear end collision if they react too slowly and or

braking is not adequate to stop.   Generally on level dry pavement surfaces the 2

second rule suffices:

The two-second rule is useful as it can be applied to any speed. It is

equivalent to one vehicle-length (15 feet) for every 8 km/h (5 mph) of the

current speed, but drivers can find it difficult to estimate the correct

distance from the car in front, let alone to remember the stopping distances

that are required for a given speed, or to compute the linear equation on the

fly. The two-second rule gets around these problems, and provides a simple and

common-sense way of improving road safety.

For instance 40mph/5mph = 8 car lengths.  60mph/5mph = 12 car lengths (180

feet).  And obviously when road surfaces are icy/snowy the safe distance increases.  V2V distance also decreases more as downhill gradient increases as well as when roads bend and turn.  And V2V distances increase as uphill gradient increases.

Depends on the time of travel when you have more experienced weekend warriors who've driven the road every weekend for years, or first-timers/once a year folks.

Regardless of the # of seasoned drivers, there are always gapers who are in go-go-go mode, and don't respect that there are sections that are specfically very dangerous.

For examples, on echo summit, usually during chain controls, it's 2lanes and *most* people have the sense to just go single file when it's a lineup as passing isn't saving you anything.  But there will always be some dude who is going to take the passing lane, to pass 5 cars even though it goes back to single file, half a mile later.

On the particular most uphill grades past twin bridges, there are 2 curves which are also 2lanes that turn into single-track convoy during chain controls.

If it's particularly icy, you better be giving enough distance that if someone loses traction and stalls out you can go around them chugging along at your 20-25mph.  (if you decide to brake, you're going to lose momentum, and likely conditions were just particularly interesting to cause you to spin out too, and you'll crabwalk right into the guardrail.

Interestingly, the engineering road design standard reaction time in Ontario is somewhere between 3 and 4 seconds.  So I don't know that 2 seconds is a good rule.  By the grace of god people don't get in accidents, not by sensible reaction time selection.

Just one guy's thoughts... I've driven in some pretty heavy snow storms (and fog thicker than snow) in New England (mountains and flats), Mid-Atlantic (flats), and Colorado (front range, high-desert, MOUNTAINS) over several decades (as a young man and lately as a pretty freaking aging one).

Get a feel for the vehicle you are driving.  If it is yours you probably know it well already.  If a rental, gently feel it out.  Just because it is a giant SUV doesn't mean it handles well in bad conditions (or good).  Try to find the HINTS of its limits.

Try to leave more room than you think you need.  If you are climbing you will slow down faster.  If you are heading down a serious Continental Divide type downhill you might need some serious space to get slowed down or stopped.   I say "try to leave" because leaving room ahead of you can be challenging and you have little control of the room left behind you.  Clowns will climb up your butt, clowns are like that.  Might be funny at the circus but it sucks when driving in serious weather.

What is your visibility?  Adjust accordingly.  Anyone who has driven in an honest-injun-whiteout knows what I'm talking about.  When you are tracking the guardrails to keep yourself centered because you can't see 50 ft ahead and clowns are climbing up your butt because it is easier to follow your taillights than figure out what's going on in in the whiteness ahead...  I've had them flash their lights, start to go around, and then back off and climb back up my butt.  If I'd been armed I would have ended that issue, let me tell ya'.

Judge the traffic around you - is everyone pretty "peaceful, easy feeling, I won't let you down", then just go with the flow.  Or is they guy ahead of you braking with every snow flake that splats on his windshield.  Sometimes safety lies with the pack, sometimes it lies with getting AHEAD of the soon-to-be-victim-of-circumstance.

Ultimately, your task is to arrive safe and sound and ski.  If you lose some time 'cause you are playing it safe but arrive safe and sound, there's no loss.  If you lose hours to dealing with the tows and insurance info exchange, or worse - an injury - then you lose.

Drive slow. Ski fast.

The reason the 4 second rule has sucumbed to 3 or 2 second rule has to do with modern traffic conditions and the expectations of driving behaviors.

The best Safety occurs when people know what to expect from other drivers and to stay with the flow rather then rules thought up in an ivory tower.

Unfortunately, in these modern times, people are both busier and everyone has to deal with commute traffic to fill the lanes provided rather than always having lanes open when you can drive how you wish.  The old 4second rule is in conflict with the modern concept of traffic.

What happens now is if you're leaving a 4second gap in a locale that doesn't expect it culturally; is people will keep trying to pass you to fill the gap.  So counterintuitively you actually become a bit of a hazard and less safe rather than more safe as people keep wanting to jump in front of you the moment your gap is enough for them to fit their car in.

Even as taught in the driving books and driving classes they changed the 4 to a 3 here awhile back.  I don't know if they changed the 3 to a 2 though.  I think they put a lot of thought into that change (at least here in CA),  they didn't just change it willy-nilly.

Quote:
Originally Posted by raytseng

The reason the 4 second rule has sucumbed to 3 or 2 second rule has to do with modern traffic conditions and the expectations of driving behaviors.

The best Safety occurs when people know what to expect from other drivers and to stay with the flow rather then rules thought up in an ivory tower.

Unfortunately, in these modern times, people are both busier and everyone has to deal with commute traffic to fill the lanes provided rather than always having lanes open when you can drive how you wish.  The old 4second rule is in conflict with the modern concept of traffic.

What happens now is if you're leaving a 4second gap in a locale that doesn't expect it culturally; is people will keep trying to pass you to fill the gap.  So counterintuitively you actually become a bit of a hazard and less safe rather than more safe as people keep wanting to jump in front of you the moment your gap is enough for them to fit their car in.

Even as taught in the driving books and driving classes they changed the 4 to a 3 here awhile back.  I don't know if they changed the 3 to a 2 though.  I think they put a lot of thought into that change (at least here in CA),  they didn't just change it willy-nilly.

Oh not arguing that..more that, the accepted reaction time for highway design is 4 seconds (3.8 I think in actuality..been a while since I did this stuff..) and we're telling people 2 seconds is enough. Tough to reconcile that!    I get the driving habits..but the science of reaction times and collisions doesn't support it!

given the number of rear enders I see on crowded freeways the 2 second rule ain't working. I learned 3 and I still think it's reasonable. Thee aren't arbitrary standards--they're based on the physics of reaction time and stopping distance. As far as people who want to fill the gap let em, it isn't going to get them there any faster. I do vary my following distance by the distance to the person behind me--the closer they get the more room I give to the car in front, so I don't get rear ended by my having to stop suddenly. Also consider that there's a 50-50 chance that the driver behind you is texting. I also consider the sight distance--if I can see that traffic is moving smoothly ahead I would follow closer than if there are curves or a big car in front of me I can't see around. I always make sure to know where the cars are on the neighboring lanes are and if traffic allows try to keep a bail-out space to one or both sides. I have never understood people who have to drive right next to you on an uncrowded road. There seems to be a reflex to match the speed of a car you are passing or that is passing you. Even worse are people who match speed with semis. Death wish?

Quote:
Originally Posted by Scott43

Oh not arguing that..more that, the accepted reaction time for highway design is 4 seconds (3.8 I think in actuality..been a while since I did this stuff..) and we're telling people 2 seconds is enough. Tough to reconcile that!    I get the driving habits..but the science of reaction times and collisions doesn't support it!

yea, you try to teach the lesser of two evils.  For a new driver, I guess they determined it's safer for them to have the short distance, versus getting cut off all the time. Getting cut off probably would lead to more swerve accidents then rear-enders.

Quote:
Originally Posted by raytseng

yea, you try to teach the lesser of two evils.  For a new driver, I guess they determined it's safer for them to have the short distance, versus getting cut off all the time. Getting cut off probably would lead to more swerve accidents then rear-enders.

Yeah, I think that's about it.  Balance defensive driving and being able to keep up to the flow.  Most of the time it works.

FYI, I will pass you any time and every time I can.

I'm definitely closer than two seconds, but in my defense, when I've been to the a science museum (more than a few times) my reflexes have always tested out at much much less time than the average.  In my judgement I'm far enough back that I can stop faster than you can, decades of licensed winter driving various vehicles and tire combinations has given me a pretty good feel for it.  If things get dicey, I will sometimes cover the brake pedal with my foot when expecting driver in front of me to suddenly brake, or when approaching closer than my auto-pilot comfort zone for one reason or another.  I always pay very close attention to my driving.

I had a series of vw. beetles and vans in the mid 70s to mid 80's. Those windshield washers rarely worked.

Then close enough that the spray from car in front still contained enough liquid to clear the windshield, before passing .

Now its far enough back that "random brake light guy" does not make me touch my brakes, before passing.

Quote:
Originally Posted by Toecutter

FYI, I will pass you any time and every time I can.

Like the guy who thought I wasn't leaving the ice-covered Alpine Meadows lot fast enough, passed me on a blind curve, spun out and skidded across the oncoming lane between 2 cars, narrowly missing both of them, before he wound up nose down in a ditch. I was also taken out on 89 near Homewood on a blizzard day by someone who decided to pass me in a Camaro, spun out, and hit me, with a wife and 2 little kids in the car. But of course you're far too good of a driver to ever do something like that, or so you think.

Quote:
Originally Posted by Ghost

I'm definitely closer than two seconds, but in my defense, when I've been to the a science museum (more than a few times) my reflexes have always tested out at much much less time than the average.  In my judgement I'm far enough back that I can stop faster than you can , decades of licensed winter driving various vehicles and tire combinations has given me a pretty good feel for it. Oh, please. If things get dicey, I will sometimes cover the brake pedal with my foot when expecting driver in front of me to suddenly brake, or when approaching closer than my auto-pilot comfort zone for one reason or another. Great--another two foot driver with brake lights coming on for no good reason. If you're so close you feel you need your left foot on the brake BACK OFF.  I always pay very close attention to my driving.

If there's one thing that's been shown time and time again--everybody thinks they're a much better driver (and a much better skier) than they are. You guys want to prove how macho your are--do it on a closed ski race course or an auto racing course, not on the road. Thank you.

Every time I pass someone on an icy or snow covered road I'm very conscious of not wanting to be that guy.   If the road were empty I would be driving the same speed but being much more relaxed about it.

You do have a point though.  How safe you are does not depend so much on your skills, once you have a minimal set, as it depends on how much of a safety cushion you give yourself, how well you know the limits and how far away from them you stay.

P.S.  I said hovering, not touching.   I only touch my brakes if and when it's needed.

One other thing to consider. Following too closely makes traffic worse. Watch a tailgater--brake lights keep coming on. When cars behind see brake lights, they brake, then the cars behind them--a chain reaction that can bring traffic to a complete stop despite there being no significant blockage ahead. If everyone backs off a little and keeps off the brakes, we all get there sooner. Same applies to lane changing and that compulsion to pull into to any open spot greater than a car length (if only by a few inches). Traffic engineers have shown repeatedly that once a road reaches capacity all lanes move at the same average speed--one lane might be faster for a while, then another, but none is faster overall. All the lane changing does is force the car behind to brake, with the chain reaction slow down I described above. If we all drive more patiently we all actually get there faster.

Eat my slush oldgoat.

While the rest of you are adding comments the below is good for several laughs.

The "good" part starts about 1:20 into the Youtube video.   And yeah I have come across black ice and it really is scary even with 4WD.  Fortunately one is  uncommonly going to run into such on highways though as conditions change it can happen hour to hour where melting water has flowed across pavement and then temperatures drops temps rapidly.   One reason I've always valued having a thermometer on the outside of my Subarus even before they became a standard item because sometimes one really notices weird changes on icy/snowy road surfaces right about the freezing point.  As someone driving for decades I've never run into another vehicle including lots of mountain winter driving.  Am one who keeps a safe distance behind other cars when roads are snowy/ icy and am not at all amused when some urban commuter traffic behavior bozo drives close behind me like snow/ice makes no difference.

The conditions in that youtube video look like snow is coming down now but falling onto ice.  I live in the coastal central NJ area where ice storms are not at all uncommon and they are, IMHO, much trickier to drive in than snow.  And snow over ice is even worse because it brings out the worst in drivers unfamiliar with it.  They think they are driving in snow which generally affords some traction but they are driving on slicked up ice which affords virtually zero traction.  On ice you have to drive incredibly sensitively, especially if you don't have studded tires and those are rarely used where occasional ice storms happen.  I've seen scores of cars and trucks stuck on a single bridge in those conditions (and got around them and over and down the other side just fine). On ice, accelerate as gently as possible, stay off your brakes, use engine braking - if you need your brakes you're rolling too fast.

Quote:
Originally Posted by Toecutter

FYI, I will pass you any time and every time I can.

Yeah but that's because you get to use the hero lane..

You guys sound like rookies.
There's an old saying in trucking. There's fast drivers and there's good drivers. But there's very few fast good drivers. Old goat sounds like about the only guy I'd want driving around me. I didn't stay at a Holiday Inn but I've drove 3.5 million miles in places most people only have nightmares about.
In Montana, there's no one on the highways. Makes it much easier.
Quote:
Originally Posted by Scott43

Yeah but that's because you get to use the hero lane..

I use the passing lane. That's why it's there.
Quote:
Originally Posted by Toecutter

Quote:
Originally Posted by Scott43

Yeah but that's because you get to use the hero lane..

I use the passing lane. That's why it's there.

You mean the passing lanes on I80 on two steep upgrades where the slowest drivers camp out? Good luck with that.

The interstate brings up different problems--like the people driving too slow stay in the right lane which is plowed and you can't pass in the left hand lane because the snow is up to your axles.

I'm thinking of 2 lane roads though.

Two weeks ago, I was driving south on I-89 near Montpelier, VT when light scattered snow showers started increasing in intensity.  I pulled into the right lane and slowed down, and then several cars proceeded to pass me at high rates of speed, while following each other far too closely in any condition.  I thought to myself these guys are crazy.  Just minutes later, we approached a multi-car accident that had just taken place, and resulted in the highway being shutdown.  Scary scene; about a 1/8 mile stretch with cars, trucks smashed up or off the road, and a turned over box truck.  Learned later that a total of 15 vehicles were involved.  Good reminder to respect changing, deteriorating conditions and be ready to adjust.  I don't think any of them followed the 2 second rule.

Edited by Hoss - 1/29/16 at 8:53am
Quote:
Originally Posted by oldgoat

You mean the passing lanes on I80 on two steep upgrades where the slowest drivers camp out? Good luck with that.

I've never skied in California.

Here we have two lane undivided for about 17 miles then a three mile section of four lane highway for the final approach. There's always someone without any cars ahead and 20 cars stacked up behind, completely oblivious. I wish they'd pull over like they're supposed to. At least there are a few passing zones where a few cars can get by.

Jesus, last week during a particularly icy morning a school ski team van was parked in the middle of the lane trying to chain up 300 yards past the chain up zone. Total mayhem that was.
Ha, if you thought backseat driving was annoying we have now invented internet seat driving.

I realize I wont be able to change your driving habits so i wont try, but I will roll down my window and flip you off as you are tailgating and passing just to remind you that I see you, and you are the ahole not me, and enjoy the 10 seconds you gained until we hit the next backup in 1 mile and we're in the same spot again.
Not to say that you should never pass if indeed its slower but in the situation of a bumper to bumper convoy who are slowed due to congestion for miles a section of passing lane isn't getting you anywhere faster, you're just dangerously wanting to skip ahead within the line thst everybody is jn. Everyone wants to go faster they just have 400 cars in front of them same as you. (Need those guys passionate about singles lines etiquette to come and argue this travesty of justice)
Edited by raytseng - 1/29/16 at 9:18am
If you make the drive up before 0800 its clear sailing. I pay taxes so I'll drive anyway I like said everyone.

Reality is that many drivers follow more closely than the two-second rule especially when driving in chains of cars in single lanes of traffic.  That is in great part because in urban areas where most drivers live and develop driving habits, leaving a standard safe vehicle distance between cars in more dense traffic on multi-lane in each direction roads is certain to result in other drivers that had been behind, speeding up, passing, then merging into that space.  If so any drivers behind the vehicle leaving such a space will become annoyed as their lane moves them relatively back into traffic.  Just reality of the herd mind set we need to deal with pragmatically.   No place does that play out worse in The West than as I80 westward, ten lanes wide approaches The San Francisco Bay Bridge.

Accordingly there are all too many urban drivers driving up to Tahoe on icy/snowy highways that follow behind other vehicles too closely by habit alone without considering the icy/snowy slippery road surface difference.  The same result occurs in foggy conditions more widely across the country with major news stories about dozens of vehicles rear ending each other.

Generally one can expect that local mountain residents who grew up in such communities are most likely to drive in winter conditions safely because they have seen it all and learned.  Next would be those who moved to the mountains and have through the years become locals.  Then would be old urban skiers like this person that have been winter driving to ski resorts for decades.  And at the other extreme are young urban twentysomethings with money, SUVs, impatience, and little experience driving in snow and ice.  A bit of poking fun at their behavior.

Others have already mentioned those who race ahead at every passing lane only to end up slightly further up in a long chain convoy of vehicles that by time one reaches the destination amounts to a piddly few minutes.  Yet at every passing lane it is game on.  The only reason I'll move up is to put some distance between a trailing tailgater that was behind.

Because they have developed the urban habit, some of the latter may be obviously annoyed if on a two lane highway where they cannot easily pass, they drive behind another vehicle that leaves a reasonable safe space even though no other drivers are going to merge into that space.  An advantage to driving with such a space in chains of vehicles besides safety issues is that one can smooth out the otherwise inevitable herky jerky braking that drivers with a lack of mountain driving skills tend to make. In other words the impatient urban habit driver behind likely tailgating may be annoyed for no reason other than they have been psychologically conditioned so and are too emotionally thick-headed to realize that.

Not sure about the picking at the youth as the only offenders.

Equally obnoxious there are plenty of mid-aged men (some with families) that because they are already well accomplished in their careers and are a big shot back at the firm, and had to deal with a commute for 20 years; paid for their new luxury SUV themselves to have the entitled to just drive as fast as they want too as well

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