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From page 34... ... 26 Appendix G DOT Response to NAS Letter Report on Electronically Controlled Pneumatic Brakes This appendix contains briefing materials presented to the committee by DOT on July 6, 2017. Summary The NAS had three primary recommendations:  Consider specific brake response profiles  Confirm parameters through multivariate analysis  Additional model validation The DOT has responded to these recommendations as outlined here:  Conducted additional field and rack testing to capture brake response profiles - Included these in the simulations and analyses  Conducted regression analysis and interfaced with the RSI-AAR project on this effort - These confirmed that the variables included in the DOT's analyses were appropriate, inclusive, and prudent  Reasonable validation has been completed NAS Recommendation # 1 Emergency Brake Propagation Profiles 1.1 Use test racks to simulate the performance of the different braking systems 1.2 Measure the time required for the emergency application of ECP brakes and DP and EOT systems from initial train separation to the point at which all of the brakes on the train are fully applied. Read the entire page →
From page 35... ... Field May 31, 2 Test for the FR Obse At variou  B  T  D  B A total of Note that brake pipe testing was 017. ing and prim A Read the entire page →
From page 36... ... 28 Overview of Watertown, NY Tests Rack Testing was conducted on NYAB brake rack with:  Conventional air brakes in both DP and EOT configurations, and  ECP brakes in a standalone configuration Testing and primary data collection was performed by NYAB and Wabtec. Observers included representatives from AAR, NS, GE, BNSF, TRB, and FRA. Read the entire page →
From page 37... ...  M – – The data fo the GE dat field condi [NOTE: T The Derailmen Analys Original Revised 2.1 Use on model 2.2 Crea accident r 2.3 Dev relates to but are kn easured time DP/EOT/C ECP Syste r the conventi a. This data in tions better th he slide repr likely numbe t) Read the entire page →
From page 38... ... 30 DOT Actions in Response – Multivariate Analysis  Collaborated with RSI-AAR [Railroad Tank Car Safety Research and Test Project] on the potential for combining the databases and conducting additional analysis  Conducted multiple regression analysis of data from FRA's RAIRS database  Both of the above actions confirmed that the variables considered in the DOT's Analysis were appropriate, inclusive, and prudent Engagement with the RSI/AAR Data Group  The RSI-AAR data group graciously agreed to engage with the FRA on this effort  Several conference calls were held and the FRA shared a potential list of questions that could be answered by combining the data sets  In the end, both parties agreed that literally merging the FRA and RSI-AAR databases does not offer any value: - However, the RSI-AAR data group identified several key variables that should be considered. Read the entire page →
From page 39... ... Overall, th ed in the D 3.1 Vali ual derailm modeled s prediction Review o large leve  T co Ther  E  It Prior wor qualitative tured  T e DOT belie OT approac date the mod ent event w cenario shou is to be com f accident dat l of variabilit he level of sc mmittee for efore, simula specially, for is more critic k published b ly shown ex his work was ves that the s h are signific NAS R eling approac ith the actual ld be the sam pared. D a (in general) Read the entire page →
From page 40... ... 32 DOT Response to Model Validation In addition, the rear car distance traveled in a comparable set of LS-Dyna simulations was compared to the Aliceville locomotive's event recorder data, and found to match with a difference of less than four percent.  This shows that in spite of all the potential variations, our derailment simulations closely matched reality, as evidenced by the event recorder download. Read the entire page →
From page 41... ... NOTE: D York. ata were obtained from te sting conduct 33 ed at the New York Air Brake facility in Watertown , New Read the entire page →

From page 34...

... 26 Appendix G DOT Response to NAS Letter Report on Electronically Controlled Pneumatic Brakes This appendix contains briefing materials presented to the committee by DOT on July 6, 2017. Summary The NAS had three primary recommendations:  Consider specific brake response profiles  Confirm parameters through multivariate analysis  Additional model validation The DOT has responded to these recommendations as outlined here:  Conducted additional field and rack testing to capture brake response profiles - Included these in the simulations and analyses  Conducted regression analysis and interfaced with the RSI-AAR project on this effort - These confirmed that the variables included in the DOT's analyses were appropriate, inclusive, and prudent  Reasonable validation has been completed NAS Recommendation # 1 Emergency Brake Propagation Profiles 1.1 Use test racks to simulate the performance of the different braking systems 1.2 Measure the time required for the emergency application of ECP brakes and DP and EOT systems from initial train separation to the point at which all of the brakes on the train are fully applied.

Read the entire page →

From page 35...

... Field May 31, 2 Test for the FR Obse At variou  B  T  D  B A total of Note that brake pipe testing was 017. ing and prim A

Read the entire page →

From page 36...

... 28 Overview of Watertown, NY Tests Rack Testing was conducted on NYAB brake rack with:  Conventional air brakes in both DP and EOT configurations, and  ECP brakes in a standalone configuration Testing and primary data collection was performed by NYAB and Wabtec. Observers included representatives from AAR, NS, GE, BNSF, TRB, and FRA.

Read the entire page →

From page 37...

...  M – – The data fo the GE dat field condi [NOTE: T The Derailmen Analys Original Revised 2.1 Use on model 2.2 Crea accident r 2.3 Dev relates to but are kn easured time DP/EOT/C ECP Syste r the conventi a. This data in tions better th he slide repr likely numbe t)

Read the entire page →

From page 38...

... 30 DOT Actions in Response – Multivariate Analysis  Collaborated with RSI-AAR [Railroad Tank Car Safety Research and Test Project] on the potential for combining the databases and conducting additional analysis  Conducted multiple regression analysis of data from FRA's RAIRS database  Both of the above actions confirmed that the variables considered in the DOT's Analysis were appropriate, inclusive, and prudent Engagement with the RSI/AAR Data Group  The RSI-AAR data group graciously agreed to engage with the FRA on this effort  Several conference calls were held and the FRA shared a potential list of questions that could be answered by combining the data sets  In the end, both parties agreed that literally merging the FRA and RSI-AAR databases does not offer any value: - However, the RSI-AAR data group identified several key variables that should be considered.

Read the entire page →

From page 39...

... Overall, th ed in the D 3.1 Vali ual derailm modeled s prediction Review o large leve  T co Ther  E  It Prior wor qualitative tured  T e DOT belie OT approac date the mod ent event w cenario shou is to be com f accident dat l of variabilit he level of sc mmittee for efore, simula specially, for is more critic k published b ly shown ex his work was ves that the s h are signific NAS R eling approac ith the actual ld be the sam pared. D a (in general)

Read the entire page →

From page 40...

... 32 DOT Response to Model Validation In addition, the rear car distance traveled in a comparable set of LS-Dyna simulations was compared to the Aliceville locomotive's event recorder data, and found to match with a difference of less than four percent.  This shows that in spite of all the potential variations, our derailment simulations closely matched reality, as evidenced by the event recorder download.

Read the entire page →

From page 41...

... NOTE: D York. ata were obtained from te sting conduct 33 ed at the New York Air Brake facility in Watertown , New

Read the entire page →

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