Before service began in March 2008, SPRINTER-manufacturer Siemens added additional brakes on the vehicles to make them compliant with the California Public Utilities Commission’s standards for light rail vehicle brake rates. These specially-made brakes are unique to California and are not found on any of the approximately 600 other similar models running in Europe. Once mechanics and engineers saw the “unusual wear pattern” on the discs about a year after the SPRINTER began service, they started planning for their eventual replacement — “when the time came,” according to Berk’s email on March 10, 2013.
The “Sprinter” train is widely used all over Europe, where it has had an excellent record. So it is quite extraordinary that California’s PUC, which has no expertise in this area, ordered changes to a proven design.
Richard Berk, the agency’s rail maintenance engineer, seems to have been made into the fall-guy for the fiasco. He inherited the CPUC insane design, and spent 3 years trying to find a suitable replacement wheel disc to meet the spec. What follows is his resignation letter:
This is to disseminate some background information and more technical detail to the rail vehicle design and maintenance community about the situation at North County Transit District that prompted suspension of service on the SPRINTER DMU operated rail transit operation in San Diego County and my decision to resign as Rail Mechanical Officer.
CPUC “discovered” an unusual wear pattern on the non-powered wheel plate mounted brake discs with hollowing that exceeds the manufacturer’s recommendation. The finding escalated to a troubling decision to suspend SPRINTER service.
Rapid wear on the non-powered wheel discs is the result of the extraordinary high brake rates for this weight vehicle that was required by CPUC for operation in California. The problem is compounded by the fact that the inboard discs are trapped on the axle by the mounted wheel and can’t be replaced as part of routine maintenance. Also the design is unique to the 32 NCTD vehicles and not found on any of the other 600 (or so) Siemens Desiro Classic vehicles running in Europe.
Bombardier, under contract to provide SPRINTER vehicle maintenance services, had formally requested a proposal from Faiveley, the foundation brake OEM, about 3 years ago for split discs that would enable maintenance replacement of the discs when the time came. Faiveley, apparently absorbed with acquiring Ellcon National and Graham-White was non-responsive until last summer when we received an unrealistic proposal for development of a new product with 44 week lead time and an $11,000 per disc cost!
Since then, Bombardier has worked to develop a realistic supply source but the timing missed by probably 90-120 days.
I am quite confident that the present condition, although not comfortable, does not pose any unmanageable risk that can’t be handled like any other much more catastrophic crisis developments in our field – the MetroNorth wheel burn off and hollow axle scare comes to mind. The situation should be managed with stepped up inspections and testing that would allow a rational assessment of the risk and enable a prudent reaction period if an obvious problem becomes apparent before replacement split discs can be delivered an installed.
Personally, I decided to resign, abruptly, from NCTD Friday a week ago after the CPUC triggered “crisis” situation developed. The decision was prompted entirely by our CEO’s unconstrained rage and focus on pinning blame rather than learning about the problem and ways to resolve it.