Saturday, May 18, 2013

Light Rail Brakes

The most dangerous part of light rail is the lack of braking ... aside from the ludicrous Gateway light-rail-on-residential-roads fiasco.

Light rail can't brake. Yet it has hundreds of names for 2 ½ types of brakes.

  ½ Deceleration
Pulling back on the throttle on a light rail train -- deceleration or down shifting in a car -- has all sorts of needlessly complicated names: dynamic brake, progressive brake, regenerative brake, service brake... Really none of it is braking, just using the motor to slow down.

Sick of seeing horrific traffic accidents, a police officer angrily pulled over yet another motorist failing to stop at a stop sign. They argue. The belligerent motorist says, “Hey, I slowed down. What more do you want?” The cop starts beating the driver with a nightstick and says, “Now, do you want me to stop? Or just slow down?!?

  1 ½ Standard Brakes
Pulling back on the throttle decelerates the train down to 3mph. The standard brakes kick in at 5mph and below. Light rail train operators don't have a separate control for the standard brakes... no foot pedal... nothing. They might not even be aware they are applying brakes below 5mph. The non-standardized world of light rail has at least four names for standard brakes: air brake, disc brake, electro-pneumatic brake, and friction brake.

A train operator once said, “Any idiot can start a train; it takes skill and practice to stop it where you want it to stop.

Spot the emergency brake button & point it out to the operator
  2 ½ Emergency Brakes

Passengers on Minneapolis light rail trains can't see into the cab because one-way mirror film is on the windows. If they could see in, they would see a red button, a mushroom-shaped button, for the emergency brakes. Once again, there are many names for it -- magnetic brake, rail brake, track brake -- which doesn't matter so much as getting train operators to use the emergency brake in emergencies.

Looking over recent light rail crashes and deaths, it seems like some cities have a transit culture that permits emergency braking and some do not.

Emergency brakes activated on powered bogie

Does Minneapolis have a culture that prevents train operators from using the emergency brakes?

Transit documentation says yes and no.

A light rail train operator was reprimanded for using the emergency brakes to stop at a red light. The operator should have used the throttle to decelerate and stop but used the emergency brake instead and was reprimanded. The operator and the union took the reprimand to an arbitrator. Metro Transit rolled on about the dangers of using the emergency brake:

“[Metro Transit] indicated that it is possible to damage the wheels of the train by such a stop [using emergency brakes] as the wheels slide across the tracks. This can create a flat spot on the wheel which causes vibrations and may even necessitate the replacement of the wheel... and passengers could have been jostled” - arbitration of train operator reprimand for using emergency brakes - MCTO-ATU, BMS Case 13-PA-0462, March 21, 2013.

Yes. Using any mechanical device runs the risk of wearing it out.

The Metro Transit Rail Operations Rule Book claims:
Safety is of the first importance in the discharge of your duties... In the case of doubt or uncertainty, the safest course of action must be taken.” - Metro Transit Light Rail 2008 - Rail Operations Rule Book 5th Edition (pages 7-8)

The most recent emergency situation on the Minneapolis Hiawatha Line (Blue Line) was on March 23, 2013.

A northbound Hiawatha light rail train hit a westbound car on East 26th Street at 6:30pm. The train pushed and crushed the driver's side of the white four-door sedan for one block before coming to halt. A fire burned in and around the car. The car's driver, 49 year old Francisco Antonio Sanchez-Andrade, died at the scene, in front of the Metro Transit rail technical support center. One passenger described the impact as, “We didn’t even feel it, that’s how soft it was,” almost as if brakes were not applied.

Sanchez-Andrade died a bloodied, fiery death, but at least the passengers weren't jostled.

How do these train operators sleep? Do they justify the deaths over potential reprimands?

If train operators are willing to stop the trains, can they stop the trains?
          Siemens S70 LRV #201 emergency braking                2.25 m/s² (if used) to stop 25 tons per car
          Bombardier Flexity Swift LF-70 emergency braking    2.73 m/s² (if used) to stop 26 tons per car

If light rail train operators can't or won't use the emergency brakes, what can anyone do?

Victims of the inability of light rail trains to stop need to know the variety of information that can aid a lawsuit. (Most should start by getting a good lawyer.) Lawyers will seek information in a Request for Production.

Things to Request: accident & incident reports (police & transit), black box event recorder data, brake-rate test reports (annual, post-accident, recent), emails, police interviews (was the emergency brake touching the rail?), post-accident medical report, Rail Control Center (RCC) communication transcription, Rail Operations Rule Book (current edition), supervisory memos, train operator certification, transit & state inspection reports, video camera recordings (inside & outside the train), visual reports (track brake on the rail), witness reports (was the emergency brake touching the rail?)

Rail Volution 2014 in Minneapolis should address the light rail culture against braking.

They won't.

A Minneapolis mechanic denied being addicted to brake fluid.
He said he could stop anytime.

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