Yesterday was a good example of why it is important to always clean your car’s windshield completely before driving. I didn’t see the accident take place, but a car that was parked on the street was pushed about fifty feet down the road, onto the grass, and into a tree. This caused quite a bit of damage to both ends of the car. The driver that hit the parked car left the scene. A few minutes later another neighbor showed up with a smashed bumper. What I think happened was this:

(Using standard cryptography alphabetical stand-in names)

It was warm but snowing (‘slushing’) just enough that car windows needed to be cleaned before driving. Alice was in a hurry and didn’t clean her windshield. In the half block between Alice’s house and where Bob was parked, Alice accelerated too much. I can tell Alice was driving too fast for a neighborhood street by how far Bob’s car was pushed given the relative masses of the two cars. Alice must have not cleaned her windshield, preventing her from seeing Bob’s car, even though it is common for a car to be parked where Bob’s was. Alice then drove back up the block, cleaned the snow off the car, and came back.

Now, imagine that instead of a parked car, it was one of the many cyclists or joggers in the neighborhood. So, please, completely clean and defrost your car’s windows before driving.

Yesterday the last of the big snow pile disappeared. There hasn’t been any skiable snow in two and a half weeks, but yesterday the last of the big pile of shoveled snow disappeared. This year had slightly more skiable days than the past few years. It was also the first time I remember that little dustings stuck around and added up to enough snow to open the ski rentals at Fox Island. We also had the best ‘big snow’ in years, even though 80 miles north of here it wouldn’t be considered a big snow. This was the first winter I really felt fast on skate skis. I’m not that fast, but my technique has improved so I can hold a higher speed with less effort, and don’t die on the uphills.

This winter also gave me the chance to re-compare ski poles. For the past several winters, I’ve been using relatively inexpensive race-style ski poles. These are a carbon fiber and fiberglass blend that is less expensive than fully carbon fiber racing poles, but are a large step up from fiberglass poles. They have a nice wide glove type cuff instead of a narrow strap, and the pole tapers into a small basket that works well in the thin crusty snow we usually have here in the land just south of real winter. But our ‘big snow’ this winter was the best we have had since before I bought the nicer poles. In the deeper snow, the racing baskets on my normal poles would catch on one of the upper crusty layers, then part way through the push would break through and sink several inches. This limited how hard I could pole. So I got out my old fiberglass poles with full size baskets. The improvement was amazing (but not surprising). Instead of light poling, I could push normally without the basket breaking through the crust layer in the middle of the snowpack. On a well broken in loop that had been taking 20 minutes, switching to the large baskets dropped my lap time to about 17 minutes. What I’d forgotten about the straight shaft fiberglass poles is just how much they vibrate. Every pole plant with the fiberglass poles starts a large vibration in the pole. With the better poles, this vibration is still there, but is almost not noticeable. This vibration wastes energy, but using the larger baskets saved enough that it was worthwhile. Next year I’ll be more willing to bring out the older ski poles.

Static friction is greater than kinetic friction.^*

In other words, if you aren’t sliding, it is easy to stay not sliding. Once you start sliding, it is hard to stop.

So stop stomping on the pedals when you drive. You’ll just make your wheels spin or lock and slide. When you spin your wheels, you are just turning the snow into an ice slick, making it harder for you and everyone after you to start or stop. So please go easy on the pedal mashing.

Suggested reading:

• Friction on Eric Weisstein’s World of Physics
• Car Talk’s Official Click and Clack Winter Driving Rules

^*Except for some cases you probably won’t encounter.

My hill-climbing technique on classic skis is much faster than it was at the start of the season. I now have much more glide for less effort. Since I had never skate-skied before this winter, my skating technique has improved even more than my classic technique. Over my first two days of skating, I became much more efficient. My style still needed a lot of work. A week ago I made a major improvement to my skating. I was doing a loop that was taking me twenty minutes at 90% effort. I tried some changes to my style and my time dropped to fifteen minutes and my effort dropped to 85%. I then spent a few hours waxing my skis, and my time and effort dropped even more. I think that I switched from a V1/V2A hybrid to a better almost-V2A technique. My V2 and V2A style really needs work, but I’m a lot closer now.

Last week was spring break, so I had time to iron many coats of wax into my skis. They should be much faster next winter. I finished with a thick storage coat of wax and put my skis away for the winter.

On Thursday, I spent some time on the Country Crown skis at Foster Park. There wasn’t enough snow to go over my tracks more than once. I ended up skiing in a spiral around the golf course. I missed the extra glide of the waxable skis. Foster Park used to be my standard skiing spot. The past couple years I spent most of my skiing time at Fox Island.

Friday, a few guys from the Fort Wayne Kayak (and canoe) Club went skiing at Chain o’ Lakes SP. I have spent lots of time canoeing at Chain o’ Lakes, but had never been there in the winter. The snow map showed twice as much snow there, so I decided to join them. I arrived late, but caught up quickly. The conditions were better than predicted. There were enough sticks poking through the snow that I decided to use my old skis. I skied with the group for a couple hours, then by myself for a couple more hours. It was a great day. The snow was (mostly) good, there were snow covered trees, cirrostratus clouds, and fresh trails to break. Chain o’ Lakes is a great place to ski. There are easy flat trails and some good hills. The winter traffic is much lower than I expected, so the snow was still in great shape. I skied an easy 25 km.

I was going to try the trails at Pokagon SP this morning, but the warm weather and rain started early.