On Sheet – Kinetic Energy

On Sheet – Kinetic Energy

ad a life and death moment the other day. Was riding my bike on a thirty mile jaunt with a friend. I’m an experienced rider, commuted for twenty-five years. I know what I’m doing.

But sometimes, I forget.

We were a mile from the car, going along a wooded trail (asphalt with gravel shoulders), doing about 16 mph. I was to my friend’s right and reached up to wipe sweat from my eyes. And that’s when I dropped my road bike wheels off the asphalt step, onto the gravel.

When I was nine, I watched drivers ed moves during summer vacation (which explains a lot). And I clearly remember the lesson that if your wheels go off the road, take your foot off the gas, slow down, and only then tried to get back up onto the paved surface.

Yes, that’s what I knew. I was even thinking that as I instinctively yanked hard left to climb back, at fifteen mph.

The tire-sides caught, bounced twice against the raised step of asphalt, and then I flew onto the path, wheel wobbling. The left pedal struck my leg. The bike lurched right. And over the handlebars I went. Came down on my shoulder – hard – and then my head – helmeted. I remember thinking how fast I’d been going as I bounced and rolled, and just how long it seemed to take to bleed off that kinetic energy of a 220  lb guy on a 20 lb bike, moving at 15 mph. Bounce, bump, scrape.

When it was all done and I’d stopped, I lifted myself to my sorry ass and felt stabbing pain in my left shoulder (and a new bony lump there). I was sure I’d dislocated it. My friend helped me to my feet. I thanked the walkers who’d stopped to assist, and then (with nothing else for it) limped the final mile back to the car, rolling my bike and carrying my helmet in my belly-pressing left hand.

And even with the chain off and dragging, my shirt ripped and bloodied around my throbbing shoulder, the dirt and distress, with my friend next to me, there is still the retired guy who biked past us and called out “Bikes are for riding”. There is always someone.

Laying in the ER room, after being told that I had no broken bones and then whatever had come out of place seemed to have popped in, an order to see the orthopedic surgeon being written up with my discharge, I thought about my impact, the rolling, being unable to stop, bleeding off everything but energy.

It made me think of the trains we simulate and how easily they stop. At last weekend’s train show, guests running our trains would come up on red signals like the automobiles they were familiar with, stopping instantly, jackrabbiting off the line.

When you think about the raw tonnage these trains we simulate actually have, you get a grasp of the kinetic energy involved. Case in point – when a train is rolling downgrade, before putting on its dynamic brakes (engine-controlled – kinda like downshifting a car) they vent a little air off the brake line to activate the cars’ air braking – this retards the cars and keeps them from slamming together when the dynamics cut in.

There are other aspects of kinetics: when a train starts against a hill, it might back down, taking in the slack before starting. That way, the engines are only pulling one car, then two, and so on until the entire train is rolling.

Momentum on model trains is a curse – I can’t tell you how (much like my near-fatal crash) a train derails a car and before you can stop, half the train is on the ground. Experienced operators should be able to simulate that momentum (even naturally), gliding to stops, easing forward at starts, without the necessity of momentum. Look, if you like running with it, fine, but you can simulate it safer with solid throttle control.

Good train handling makes us better train operators. And if you run slow and methodically, you’ll notice everyone around you doing likewise. It makes for a better session and one that is more enjoyable. Like stopping to hand-throw turnouts, like slowing for a signal, all this adds up to a better session for you. They aren’t toy trains anymore. They are real locomotives.

So run your trains like they have velocity and energy behind them. Just the way I didn’t the other day with my bike on the trail.