Northgate LRVs on schedule, but risks remain

Siemens and Kinkisharyo vehicles in Bellevue last weekend (image by author)

The Sound Transit System Expansion Committee received an update yesterday on the availability of new Siemens vehicles to support the beginning of service to Northgate this Fall. Significant risks remain, but progress has been made since a previous report in November. CEO Peter Rogoff expressed confidence that Northgate Link will open on the intended schedule.

A minimum of 30 cars must be available to open Northgate service with the full complement of four car trains at eight minute headways.

Sound Transit had baselined the Northgate project with 40 cars being available by end of 2020. That plan was knocked off track by a series of early supply chain holdups and later testing issues, and further complicated by COVID. Manufacturing is now on schedule and on budget. Commissioning, the lengthy series of steps between manufacturing and putting cars in service, remains behind schedule. When we last reported on this in November, Sound Transit was pursing a recovery schedule' to get the needed minimum of 30 cars ready by the opening of Northgate in September 2021.

Are they on track? 37 cars are now in Seattle (vs. 26 in November), with 20 ready for mainline testing (vs. 12 in November). The largest single problem remaining in November, a signals interference issue between on-board subsystems, has been resolved.

If all goes as scheduled, the first six cars will be available by the end of March. That's enough to put the first train into service (with two vehicles as spares). The significance of the qualification vehicle' goes beyond just having one train available. In important ways, it verifies the design is performing as expected, and prepares the way to move the following vehicles through burn-in to verify reliability.

Staff characterized the path forward as a reasonably achievable schedule with 42 days of float (at the time of the November report, there was still two months of float).

Whether all the needed LRVs are ready by September seems to hinge on whether there are any more adverse surprises, with the greatest unknowns in the next several weeks. There will be another update to the Committee in Spring 2021.