The Case Of The Lost Indication

My train stopped in the tunnel today. “I lost the indication. Do you have it?” — called out the operator to the conductor over the PA system. Sometimes instead of using walkie-talkies they use overhead PA to communicate. Probably by mistake, because hearing subway jargon spewing from the loudspeaker in a stopped train freaks out passengers.

“I lost the indication here too ” — said the conductor. We were stuck for at least half an hour before the train started moving again.

As it turns out, a signal is called and “aspect”. For instance red light is a red aspect. And an “indication” is the meaning of an aspect in a context. Red aspect’s indication is usually (but not always) – stop. So apparently what the machinist and the conductor meant was that the signal light they were expecting was off. When there is a power loss to a signal a trip arm automatically extends up from the track (it’s up motion is powered by a spring, so it automatically engages when a signal loses power). If a train passes an extended trip arm it trips an on/off switch on the train and you get stuck for much longer.

I need to get a scanner with subway frequency.

Blue Lights In The Tunnel

Was taking pictures from the front window of an R40 train again. By the way, in theory it’s ok to take pictures in NYC subways without a permit unless you use “lights” (this may or may not include flash), a tripod for non-commercial purposes. It’s a complicated issue and is pretty open to interpretation, and in fact transit cops might not be aware of it at all. I had been asked by a transit cop once to stop taking pictures and erase what I already shot because of “the 9/11 stuff”. I told her politely about MTA rule Section 1050.9, Paragraph (c), but as I had no desire to argue with her also erased the pictures. You see, if I wasn’t lazy and got an official permit which supposedly “can be obtained from Division of Special Events by contacting Connie DePalma (718) 694-5121, 9 a.m. to 5 p.m., weekdays” I could show that to her. Besides, nobody likes a dorky smart ass with a camera.

Anyway, the pictures are pretty, but “hold on Luke, we are going into hyperspace” effect becomes tiresome fast enough. So I’ll spare you. Here’s a slightly more interesting shot taken handheld at 1/10th sec., f/2.0 ISO 400 while the train was standing in a tunnel (if your monitor brightness is set too high, you might not see the details). For all the coffee that I consume my hands are pretty steady.

I always wonder how it was for the people stuck in the tunnels during the blackout. They probably actually had to walk through whole tunnel stretches like that to get out after a while.

The train signaling system is not too complicated. I think I figured out a sizable chunk of it from just watching the tracks, and the rest can be picked up from here. There’s even a “train simulator” for Windows (but for some reason the coolest part, “cab view”, doesn’t work for me.

“… The color aspects of subway signals are vaguely similar to those of street traffic lights — red means “don’t go, but stop,” yellow means “slow down,” and green means “go”. The similarity, however, ends there. Green does not just mean “go”, but certifies that the next signal, the one after the green one, doesn’t say “stop”. Yellow is even more different in meaning: While a yellow street traffic signal means “slow down, because this signal is in the process of changing to red” (which many motorists, of course, interpret as “speed up so as to pass it before it does”), a yellow subway signal means “slow down, (most often) because the next signal already is red, and you must slow down and proceed with caution before reaching it. While street traffic signals usually go from green to yellow to red, subway signals usually go from red to yellow to green…. “

Blue lights probably indicate locations of emergency phones, but could be something else. I am not sure.