A not so current article related to a current thing -
Electronically controlled pneumatic brakes study ‘inconclusive’ NEWSWIRE
By R G Edmonson | October 5, 2017
National research board says it is unable to support government claims about electronic brakes -
A Transportation Research Board committee on Oct. 5 reported that results were “inconclusive” in a year-long study of the effectiveness of electronically controlled pneumatic brakes to reduce the risk of derailment and fire in a train carrying flammable liquids.
“The committee is unable to make a conclusive statement concerning the emergency performance of ECP brakes relative to other braking systems,” wrote Louis J. Lanzerotti, committee chair.
Computer models again. Government experts, are usually are not expert.
"The FRA supported the ECP brake rule with data from a computer model that showed the brakes could reduce the effects of derailments and tank punctures by 20 percent. The Association of American Railroads and the Railway Supply Institute used a different model to show that the safety benefits of the high-tech brakes was “marginal,” according to the Government Accountability Office. The government watchdog turned the problem over to the Transportation Research Board in October 2016."
Assumptions based on assumptions.
"The TRB committee looked at the FRA model, and ordered field tests to gather additional data. In the model, a theoretical train traveling at 40 miles per hour derails on a curve. Cars directly behind the motive power go off the tracks. All of the cars are the newest, most sturdy tank cars specified by the Department of Transportation, the DOT-117.
The FRA ran its simulations with the additional data and found that in a train equipped with conventional air brakes, an average of 25.5 cars would likely go off the tracks; six of them would puncture. The same train equipped with ECP brakes, 21 cars would derail; 4.7 would puncture.
The committee report concludes that FRA’s efforts to validate its simulation “do not instill sufficient confidence” that the electronic brakes performed better than conventional systems in emergency braking situations. However, the committee’s work orders did not include making recommendations to policy-makers."