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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Broken Rail and Rollout Detection to Support QMB Operations

Document Series
Research Results
Federal Railroad Administration
Report Number
RR 21-21
Subject Positive Train Control
Quasi-Moving Block (QMB), next generation track circuit, NGTC, track circuit enhancements

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: Tuesday, September 28, 2021