Interesting article here from the WSJ about Congressional requirement for positive train control and what happens when Congress legislates technological fixes to perceived problems.
In a nutshell, Congress passed a law in 2008 that high traffic railroad lines had to have a Positive Train Control (PTC) system installed by this year. Unfortunately the mandate didn't allow much leeway in how this goal would be accomplished. From what I have read, the railroads weren't allowed to just use a computerized system and GPS but had to have transponders on trains, which of course required antennae along tracks. Years of arguing with the FCC over frequencies and transmission rates, along with the expense of installing all those antennas kept a decent system from being installed.
Congress never learns. If you mandate a specific technology rather than a specific outcome, you get an inefficient, backwards looking, expensive result. Often these mandates are the result of someone (the company or person who stands to benefit the most from the specific technology requirement?) lobbying Congress.
(Aside: We have a requirement here in Washington state that our state ferries be built by a Washington company. Only problem, there is only one Washington company building ferries. Wonder who pushed for that law?)
Perhaps it is time for Congress to back off and pass more general requirements that allow for the inventive use of existing and new technology to solve problems. Unleash the private sector.
PS In spite of all the political spin about the Amtrak crash, the operator was going 107 miles per hour in a 50 zone. Anyone who thinks that changing the limit at that curve to 45 is going to stop the next crash is delusional.
NOTE: WSJ is subscription only so I just linked to a summary from NCPA.