For my birthday, Nancy took me on a trip to Jackson Hole.Part of the trip was a journey in to Yellowstone National park in a snowcoach.The snowcoaches are modified vehicles to handle to snowy terrain.They come in two main forms.One is the tracked vehicle and the other is based on monster truck tires.The one we took was tracked.It was a pretty standard van design with four wheel drive but the wheels had been removed and replaced with triangular track arrangements called Mattracks.These can deal with pretty much any snow.The only downside is that they are a bit noisy, not too fast and boy do they guzzle fuel.One our trip we stopped for fuel twice and were pretty low by the time we got back.
We also saw some of the other vehicles out and about. The monster truck tired vehicles can attain better speeds and efficiency (plus the maintenance is so much lower) but they are not as reliable in dealing with the worst of the conditions. However, they do seem to be the way that everyone is going. Our guide told us the tracked vehicles are gradually being replaced. It should be noted that, after the winter, the tracks are taken off and they revert to normal road use.
I was photographing some evening arrivals at Vancouver and, as I went through the shots afterwards, I got to see some detail on the tires that I had not noticed before. The tires’ surface has a matt finish as you would expect of rubber. When they hit the runway they go from zero rotation to very fast rotation extremely quickly. The friction that causes this rapid run up scrubs a bit from the surface of the tire making the familiar smoke.
What I didn’t know is that the heat changes the appearance of the surface of the tires. They suddenly become very shiny. In these shots you can see wheels of a 777 just before and just after contact. Also there is a shot from an A321 where you can see some of the tires have touched down and others haven’t. Only with the low sum angle was this obvious.
Touchdown of an airliner almost always results in a big cloud of smoke as the rubber burns off the tires when they spin up to speed after first contacting the runway. Lots of tires can mean even more smoke and the 20 main tires on an A380 should mean a lot of smoke. Less often noticed is that the same thing happens when the nose gear touches down. As I shot this A380 landing at LAX, I happened to catch the smoke from the nose gear as it hit the ground.
I was skimming through some shots from Tucson to thin out the shots that I got from that day. I looked at one of the shots because I thought that there was something wrong with the shot. When I checked a few of the surrounding shots, I realized that there was nothing wrong. The shot was real. The F-16 had a tire that was looking very sad. I know that budgets are tight but I think they need to change the tires on this jet.