Question: Can trains get flat tires?
Someone apparently found their way here searching for the answer to this question. I hadn’t answered it yet, so here it is now. The answer is yes, sort of – a train will not get flat tires like a car can, but train wheels can develop flat spots. You’ll know if you’re on a train with a flat because it will sound like this:
Westbound into Sunset TC, sitting over the C truck of a Type 4 that had a flat
The trains should run pretty quietly – a “chugging” sound like that is indicative of a flat.
Flats can form on slippery rails or when the train makes a sudden hard stop, and bad flats on a train will get it pulled out of service so the wheels can be repaired.
Camelopardalis
A UIC professor of mine who used to work at the CTA spearheaded a “noise pollution” study to find out where/how the trains made noise.
A conclusion was that if they rounded the wheels and greased the curves, noise (measured in decibels) could be cut almost in half.
Yep, TriMet uses those greasers as well in a number of places for noise reduction.