# Seattle First Hill Streetcars out of service



## CHamilton (Mar 11, 2017)

> 2½-block skid has Seattle scrutinizing streetcar safety
> Originally published March 11, 2017 at 7:00 am Updated March 11, 2017 at 2:01 am
> 
> A train skidded last week on the First Hill line — a risk the city must address there, and on the future First Avenue streetcar near crowds of pedestrians, to open in 2020.
> ...



http://www.seattletimes.com/seattle-news/transportation/2-block-skid-has-seattle-scrutinizing-streetcar-safety/


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## CHamilton (Mar 23, 2017)

The First Hill Streetcars have been operating again since Monday. Here's a report on what happened.

https://sccinsight.com/2017/03/21/sdot-reports-first-hill-streetcar-failure-next-steps/


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## Devil's Advocate (Mar 23, 2017)

> The problem with relays is that they are mechanical systems with moving parts, and moving parts all eventually fail. The streetcar had one of these controlling the braking systems, and it failed. That’s not unusual; what is unusual is that it exposed a major design flaw in the streetcar: *all of the braking systems were controlled by the same load contactor*. That’s called a “single point of failure” and it’s a big no-no in electrical systems design — _especially_ critical systems like brakes.


That's not just dumb, that's DC-10-10 levels of stupidity.


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