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Broken Rail and Rollout Detection to Support QMB Operations

Document Series:
Research Results
Author:
  • Federal Railroad Administration
Report Number
RR 21-21
Office
RDI-23
Subject:
Positive Train Control
Keywords:
Quasi-Moving Block (QMB), next generation track circuit, NGTC, track circuit enhancements
Document
RR_Broken Rail and Rollout Detection-A.pdf (434.56 KB)

Transportation Technology Center, Inc. (TTCI) collaborated with a railroad advisory group to progress a track circuit concept that supports the Quasi-Moving Block (QMB) method of train control. TTCI performed proof-of-concept testing, capacity analysis, hazard analysis, and requirements development.


Last updated: Friday, August 15, 2025