Friday, October 10, 2008

CalTrain Studies Crashworthiness

The Federal Railway Administration sets safety standards for the nation's railway network. Their safety standards for passenger equipment emphasize crash survival through strength. The result is that US passenger equipment weights 2x3 times more than that used in other parts of the world, increasing energy consumption, and making off-the-shelf equipment from other parts of the world prohibited.

CalTrain, which would like to evolve from diesel-powered mainline-style trains to electrical multiple unit trains (i.e., a slightly scaled up version of BART) has studied the effectiveness of US and European safety standards, and concluded that the FRA's "build trains like tanks" mentality is probably not making passengers any safer; I'll excerpt a summary table:

Impact Object Speed Probability European CEM FRA-Compliant
Automobile All High Negligible Negligible
Truck 30 Low Serious Serious
Truck 50 Low Serious Catastrophic
Truck 70 Low Serious Catastrophic
Steel Coil 20 Very Low Marginal Serious

Collisions between passenger trains and freight trains are another matter--but could be avoided entirely by restricting freights to late night hours after CalTrain has finished running (this has been done elsewhere where light rail operates on freight lines), on the main SF/SJ part of the line. This would mean operating trains south to Gilroy with different equipment, but probably there isn't enough traffic to justify electrification of the south end of the line anyway.

Thanks to Peter Ehrlich for forwarding this report to the SFMuniHistory list.


Yokota Fritz said...

"...the end of a cab car must be able to sustain an impact with a 10,000 lb coil." I'd like to see video of that test.

I wonder how much institutional momentum there might be in FRA's rules? i.e. what do the rail unions say about going to Euro-style safety standards?

arcady said...

The FRA rules were made up sometime around the 30s for the safety of postal workers riding in mail cars. When the Acela was introduced, they bumped up the numbers by 25% with no justification for that particular figure. As for separation between freight and passenger trains, in Europe the general policy is that signals and automatic protection systems are adequate to provide separation, and the focus is much more on preventing crashes than on making them survivable, which seems on the whole like a much better idea, though it does require spending more. But if Caltrain installs something like the ACSES system that Amtrak uses in the Northeast Corridor, the chance of a collision between trains is reduced so much as to be insignificant, unless some horrible coincidence happens like a guy parking his SUV on the tracks, and two trains passing simultaneously.