Metro has submitted a plan to The Washington Metrorail Safety Commission (WMSC) that brings the return of 7000-series railcars a little closer, though there is still not an exact timetable for when they will be operational.
A derailment on the Blue Line in October led to the discovery of a fault on the 7000-series trains that allowed the wheels to drift too far on their axles and lose connection with the track. All 7000-series trains were then ordered off the system so an investigation could be conducted on how best to address the issue.
Metro said it conducted tests on the sidelined railcars and found that in worst-case estimates, wheel movements would lose conformity with Metro specifications (and thus could set up for a potential derailment) after 10 days of operation. The transit authority said it would inspect the railcars every eight days as an added safety factor.
In a letter to WMSC, Metro said the calculation of that rate required a few assumptions to be made, and so it has planned two tests that would simulate railcars under normal service conditions and compare the results against the estimates.
If the testing verifies Metro’s estimates, it will build the eight day inspection interval into the final safety proposal it will send to WMSC for approval in order to bring the 7000 series railcars back into service.
Metro is currently operating their service at a heavy deficit, as the 7000-series trains represent roughly 60% of the transit authority’s total fleet. Earlier this week, Metro began the process of bringing 2000- and 3000-series trains back into service from the Shady Grove Rail Yard, though delays are expected to remain until the newer railcars can return to service.