DerekC
Established Member
I think many on this Forum may be interested in the above report which has just been published on the RAIB/Government website. The message (which I think might have been stated more clearly) is that the lessons of the Clapham accident are being forgotten and if the industry doesn't mend its ways we will have another serious accident with broadly similar underlying causes:
https://assets.publishing.service.g...side_failures_of_signalling_-_v2_May_2024.pdf
Here's the Overview
It's a very good report, but the overview only covers one (Assurance of Software Products) of the three areas of learning included in the report. I can't post the full text of the others, but here's am very quick precis:
Signalling line commissioning processes - Strict controls are needed on any temporary modifications to be carried out during all stages of a commissioning process. In 2016 the rules were not followed during stageworks at London Waterloo and resulted in a low speed collision between a passenger train and a stationary engineering train. The actions of staff in both incidents were inconsistent with the behaviour expected of licenced testers and the competence management processes operated by Network Rail. In addition, some of the contractors had not addressed the full requirements of the roles responsible for the design, testing and commissioning of the work.
Maintenance renewals - Signalling equipment, and its interfaces, require maintenance throughout its lifecycle. When routine maintenance or an arising failure requires equipment to be replaced on a like-for-like basis, the processes differ from those required for resignalling projects. These processes are less complex and reflect the need for simple changeovers to be undertaken quickly and efficiently, often at the site of the equipment concerned. Although maintenance replacements have a simpler method of working, the processes and culture must remain robust. In the incidents at Dalwhinnie in 2021 and Wingfield in 2022 there were failures with different immediate causes, but in both cases the equipment was put back into service without adequate testing, so failing to reveal an underlying fault involving incorrect wiring.
https://assets.publishing.service.g...side_failures_of_signalling_-_v2_May_2024.pdf
Here's the Overview
It's a very good report, but the overview only covers one (Assurance of Software Products) of the three areas of learning included in the report. I can't post the full text of the others, but here's am very quick precis:
Signalling line commissioning processes - Strict controls are needed on any temporary modifications to be carried out during all stages of a commissioning process. In 2016 the rules were not followed during stageworks at London Waterloo and resulted in a low speed collision between a passenger train and a stationary engineering train. The actions of staff in both incidents were inconsistent with the behaviour expected of licenced testers and the competence management processes operated by Network Rail. In addition, some of the contractors had not addressed the full requirements of the roles responsible for the design, testing and commissioning of the work.
Maintenance renewals - Signalling equipment, and its interfaces, require maintenance throughout its lifecycle. When routine maintenance or an arising failure requires equipment to be replaced on a like-for-like basis, the processes differ from those required for resignalling projects. These processes are less complex and reflect the need for simple changeovers to be undertaken quickly and efficiently, often at the site of the equipment concerned. Although maintenance replacements have a simpler method of working, the processes and culture must remain robust. In the incidents at Dalwhinnie in 2021 and Wingfield in 2022 there were failures with different immediate causes, but in both cases the equipment was put back into service without adequate testing, so failing to reveal an underlying fault involving incorrect wiring.
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