Tom Morgan builds our snowvan conversions for us. In this photo, Tom is building the part of the conversion that connects to the front wheel hub of the van. Not only does this crucial part support the front of the van, it also controls the steering of the front skis of the conversion. It is an amazing thing to watch Tom turn a pile of steel into a snowvan conversion.
In the photo to the left, Sarah has removed the rear axle and driveline of the wheeled van "Zillah". She is now in the process of lifting the van a little over 2 feet into the air in order to slide the conversion undercarriage under the van body.
Removing the Conversion... The 22 second video below shows us taking a snowcoach conversion undercarriage off of the van.
Converting a wheeled vehicle into an over snow machine is not a new idea. This over snow conversion unit (on a 1923 Model T Ford) is on display at the Smithsonian Museum of American History in Washington D.C. The vehicle in the Smithsonian display was used to deliver the United States mail.
* (Trivia) Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds is actually a quote from book 8, paragraph 98, of The Persian Wars by Herodotus, a Greek historian. During the wars between the Greeks and Persians (500-449 B.C.), the Persians operated a system of mounted postal couriers who served with great fidelity. More than two thousand years later those words were chiseled in gray granite over the entrance of the New York City Post Office (James A. Farley building) at Eighth Avenue and 33d Street in Manhattan and became the United States Postal Service motto.
The roadways within the interior of Yellowstone National Park are not plowed during the winter season. In order to travel to the Yellowstone Yurt Camp and to the many cross-country ski and snowshoe trail-heads around the park, Yellowstone Expeditions uses tracked 10 passenger vans.
The normal wheels and axles of a standard passenger van are removed and in their place is attached a track conversion kit. This allows for the comfort of a modern van with heater, large viewing windows, comfortable ride, and low noise level in an over-snow situation. All over-snow vehicular travel in Yellowstone Park is restricted to the unplowed roadways. No oversnow vehicles may travel off of the established snow roads. This leaves all of the Yellowstone backcountry available to the cross-country skier and snowshoer.
These van conversions place over 40 square feet of track and 20 square feet of ski surface on the ground. This results in a ground pressure of less than one pound per square inch. That is about the same pressure that a cross country skier places on the snow while skiing.
A few of our snowcoaches use low pressure tires (they run at about 8 psi) for traveling through the snow. These snowcoaches are best when the snow conditions are low, with occasional thin spots on the snow roads.
We offer several different "difficulty levels" of snowshoe trips each day. Some of the snowshoe trips start right from the Yellowstone Yurt Camp, while other trips start from trailheads a few miles from the camp. We travel to the trailheads in one of Yellowstone Expeditions Snow-vans. Here snowshoers get dropped off at the trailhead for Dunraven Pass and Washburn Hot Springs.
The National Park Service does not plow the interior Park roads during the winter season. During a normal winter, several feet of snow builds up and covers the road surface. Because of this snow, the only access to the interior of the park is by snowmobile or "snow-coach". All oversnow vehicles in Yellowstone are required by law to stay on the snow covered summer time roads. This leaves the other 2 million acres of Yellowstone accessible only to cross-country skiers.
Spring road plowing in Yellowstone starts just after the first Sunday in March. Our season at the yurt camp ends when the plows cross our driveway the second weekend of March. There is often four feet of snow packed on the road surface by the time the plowing starts.
The normal method for plowing is to mount a V plow on the front of a huge front end loader or road grader. A bulldozer (or two for deep snow) is then connected to the front of the V plow with a heavy chain or cable. The front end loader pushes, the bulldozer pulls, and presto, the snow is stripped off of the road in one pass. The Walters follows the V-Plow, pushing the snow that was torn up over to the edge of the roadway. Then several large snowblowers widen the road and do the final clearing.
Each year we feel a bit of sadness as we pack up the snowvans for the last time and head down the road in front of plows.
Snowplowing Video released by the National Park Service in Yellowstone.
This video can also be found at https://www.nps.gov/yell/learn/photosmultimedia/minute_springplowing.htm
Each spring, park roads close while crews clear a winter's worth of packed snow from the Grand Loop. Depending on conditions, the amount of road cleared in a day can be measured in miles...or yards. Here's a peek at what crews face while they ready the park for peak season.