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July 16, 2018

Fred Dyson’s Alaska Winter Driving Safety

Special Guest Post from Assemblyman Fred Dyson (Eagle River)

WHEN THE ROADS GET SLICK AND THE FOOLS ARE OUT DRIVING

(ADVICE FROM AN OLD RACE CAR DRIVER)

The first snowfall of the year brings a rash of ditch divers and car crashes.  My kids and I used to have a game of rating the wrecks when we drove between Eagle River and Anchorage.  The ditch divers, whom we scored as a 10, managed to cross four lanes of traffic, clear the guardrail, do a complete roll or summersault, and land on their wheels without hitting another car.  You can come up with your own way of scoring these esoteric accomplishments.

PLANNING FOR SAFE(ER) WINTER DRIVING

Keep your brakes and steering in top condition.  Have your windows and mirrors clear, your headlight lenses clear, and the wipers and window washers working well.  Carry a tow strap, flashlight, a CELL PHONE, warm clothes, probably chains, and have the best winter tires you can afford FOR YOUR KIND OF DRIVING CONDITIONS.  All four tires should match in size, wear, tread design, and studs.

Knobby snow tires are good for deeper snow, but they have less contact surface between the rubber and the road and are not as good as a smoother treads on ice and compact snow.  Technology keeps working for us and the new winter tires are far better then what was available a few years ago.  Read the consumer reports, make your best choice, and then keep the warm tire air pressure close to the recommended level.  If you drive a pick up, put four hundred or more pounds in the bed and tie it down.  Unloaded pickups have poor traction and squirrelly braking.

HOW TO GET CRACKS ACROSS THE BOTTOM OF YOUR WINDSHIELD

Many Alaskan vehicles have a horizontal crack across the bottom of their windshield.  This is invariably caused by turning the defrosters up full bore while the interior of the vehicle and the windshield are very cold.  The defroster heats up the bottom of the windshield glass, which expands before the middle and top of the windshield.  This differential thermal expansion fractures the glass at the location of the greatest temperature difference.

DRIVING PRECAUTIONS

Put your winter tires on before the rush of the first snowfall.  Know the weather forecast and give yourself more then ample time to get where you are going.  Plan for accidents, ditch divers, and tow trucks.

Drive defensively.  My wise truck-driver father said, ”Drive like porcupines make love – slowly and carefully”.  Leave lots of room between you and the car ahead of you.  You need room for reaction time, stopping, and maneuvering.  Never “overdrive your headlights”, which means to not drive faster than a speed at which you can deal with any situation that appears at the limit of your head lights.  Watch for flashing brake lights ahead of you and look for soft safe ditches to drive into if you can’t stop before hitting the vehicle ahead of you.  If you start to slide on ice, get off of the brakes and look for white snow on the shoulders to get a wheel onto.  The white compact snow always provides better traction than black ice.

If you have great tires and anti-lock brakes, watch your rear-view mirror when you are braking because the driver behind you may not be able to stop as quickly and may rear-end you.  Slow down BEFORE you get to traffic lights, off-ramps, or curves.  Avoid all sudden maneuvers if possible.  They will cause your tires to break traction and you lose control.  If there is deep snow on the road shoulders, beware of getting your passenger-side tires into that snow.  If the shoulder snow is deep, avoid exploration of the ditch.

Concentrate.  There are times in life that demand all of our attention.  Driving on slick roads in traffic with limited visibility is one that ranks right up there with landing on bush strips with a crosswind, angry bear encounters, divorce settlements, and political promises.  Split seconds of inattention can lead to very bad encounters with vehicles, immovable objects, ditches, cops, tow trucks, and insurance companies.

FOOLS

We seem to have a new crop of fools on the road each fall.  They drive too fast for conditions, follow too closely, weave in and out of traffic, pass unsafely, and endanger everyone on the road.  It would be only an annoyance if they had accidents by themselves, but they must like company and attention, because their stupidity and dangerous conduct often involves many others, often with tragic results.  Get their license numbers and call the police if you can.  Let them go and get out of the way.  Shake your fist, swear at them, or pray for or against them, as is your proclivity.  I wish we could mark their vehicles with paint balls.

HOW TO HIT A MOOSE

Hitting a big moose is a non-trivial event.  A moose is bigger than a saddle horse with longer legs.  If you hit one amidships, the body of the moose will hit your windshield and crumple the front of your cab.  Even if your seat belt and air bags work perfectly you will have hair, guts, and glass fragments all over you and your front doors may be jammed.  I recommend hitting the moose’s hindquarters if you can.  After the accident, get your vehicle off the road if you can, and watch out for the vehicles behind you.  They may not be able to miss your vehicle and this may be an inopportune moment to meet new friends.

SLIPPERY ROAD DRIVING PHYSICS

You cannot steer, stop, or accelerate if your tires are spinning or sliding.  If you lock up your front wheels, you lose all ability to steer.  If they are sliding, you will get very little braking and no steering effect.  Modern anti-lock breaking systems (ABS) are very good at keeping your wheels from skidding.  If you do not have ABS, pump your brakes gently as you steer through the skid.  DON’T LOCK UP YOUR BRAKES.  One of the most difficult thing humans are ever called to do is to get off the brakes when you are sliding toward an imposing obstacle.  It ranks up there with the difficulty of keeping your mouth shut in the presence of idiots.

If you lock up your brakes in a curve, your tires will lose their lateral grip and centrifugal force will start taking you to the outside of the curve.  An unloaded pickup, without ABS, will generally lock up the rear wheels first and go off the road stern first.  A front wheel drive car without ABS will tend to go off the road front-end first.  If you lock up all four wheels simultaneously in a curve, you will tend to have the end of your vehicle with the engine leave the road first.  Those of us who drove air-cooled Volkswagens or raced early Porches, got used to going off the road backwards.

If you are in a curve and back off on the accelerator, the so-called trailing throttle phenomena, the driving wheels will tend to loose traction and head for the outside ditch.  A front-wheel drive car will go off frontward (under steer) and a rear-drive rig will go off backwards (over steer).  If you apply more throttle (leading throttle) in a curve and the driving wheels start to spin, your vehicle will, again, start heading for the outside ditch with the driving wheels leading the way.  With a rear wheel drive vehicle, you should get off the throttle gently, and turn your front wheels in the direction you are sliding to retain control.  With a front-wheel-drive car, you should turn the wheels in the direction you want to go and accelerate gently without spinning the drive wheels.  Prudent winter driving practice requires not changing power or braking applications significantly in a curve.  Adjust your speed before the curve.

CROSS WINDS AND ADRENALYN RUSHES

Sudden gusts of wind from the side will generally not cause a problem with most modern car aerodynamics.  Slab sided vans, SUVs, and high loads or campers can be a different matter.  Vigilance is required.  If there is snow on the road, blowing snow may give you a warning of what is coming.  Bending trees are also a good indication of wind velocity and direction.  Slow down and stay to the upwind side of the road.

GREMLINS IN YOUR CRUISE CONTROL, AUTO TRANSMISSION, AND “TRACTION CONTROL”

These modern devices are very useful but they can sabotage you on an uphill.  On a hill, if you are holding a constant throttle, or the cruise control is trying to maintain a constant speed, there may come a point at which the increased load from the hill will signal the transmission to downshift.  The resulting increased torque to the driving wheels may cause them to spin.  If you are on a curve, you will once again start heading for the outside ditch with the driving wheels leading you.  Regardless, your driving wheels will start spinning and you will slow down.

I recommend not using cruise control on ice and reducing throttle gradually on long uphill grades to eliminate the possibility of a transmission downshift and wheel spin.

If you are using the breaking effect of your idling engine to hold your vehicle back as you descend a slippery hill, you want to move the gear selector into a lower gear BEFORE YOU START DOWN THE HILL.  If you shift down during the descent, you may once again be in a trailing throttle situation with the driving wheels sliding and you heading for the ditch.  Shifting up does not provide the same problems, or thrills.

Some “traction control systems” will cut power to your engine if the tires start spinning.  This is great for retaining control, but it does not allow you to get a run at a hill or to bust through a snowdrift.  I recommend having a traction control system that can be switched off.

_____________________________________________________________

That’s it.  Being prepared, planning ahead, understanding the physical principles involved in driving on ice, paying attention, avoiding fools, and having the presence of mind to use the correct technique at the right time should get you home safe.  If not, have warm clothes, a flashlight, a good book, toilet paper, drinking water, baby wipes, and a change of underwear with you in the car.

Winter driving in Alaska is fraught with, anxiety, excitement, and life changing spiritual experiences.  There is some evidence that fervent, even panic, prayer may be efficacious.  When my wife was looking for comfort for her winter driving fears, she found this Bible verse, ”I shall trust in the Lord with all of my integrity and therefore I shall not slide.”

I hope YOUR integrity and brains keep you safe this winter.

Editor’s note:  Fred Dyson is a mechanical engineer who has been collecting and working on cars since childhood.  He built, tuned, and raced drag racing and sports cars for several years (with very little success); and closely follows automobile technology.

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