Police stop MUNI train

I live on a Muni LRV (light rail vehicle) line so the various different noises the train makes become second nature, some of the conductors ring a bell if there is a pedestrian on the right of way ,some honk the horn ,some only honk for cars , and then there is the sound of the brakes , well there are at least two distinct sounds, from what I   under overstand (I just learned how to use strike through!!) there are three seperate braking systems on the LRV's( more on that later). One of them ,which I assume must be the standard one they use at the lights and what not is a short hydraulic sounding PFFTT, followed by a slight sound like sanding sheetrock right before you paint, this is the one I hear most of the time.

      Once in a while there is a different sound ,it's a louder release of air with a loud clunk after a few seconds followed by a much louder sanding sound that sound more like metal on metal , once in a while this will be interuppeted by the sound of impact and thats what I heard the other morning. I looked out the window and it was a patrol car that got hit (last time it was an 18 wheeler). Well I grabbed a camera and went to make sure everyone was still alive. This was about dawn of the last day of 2011.
      I got down to the corner and one of the officers was guiding his partner back on the sidewalk (UMM.. we have to stay out of the street) , I asked them if they were alright and they both said yes thanks. I then asked them if they wanted me to call 911.. they almost laughed. I took a shot with the digital camera I had grabbed and it looked really bad, I had just put a roll of 3000 speed in the polaroid  180 the night before ,so I went back inside and fetched a tripod and the polaroid I was back outside just as the first responders were arriving.
  You would have thought there were free donuts ... the sad thing is no matter who was a fault the taxpayers are paying for this one, not like when the 18 wheeler truned into the train next to him little more clear cut in that instance (couldnt find my photos of that)..in any case it barely made the papers some of the LRV conductors I talked to said that if it was MUNI's fault it would have been on the front page.