In this fifth podcast about the impact of software failures on railway asset safety, Dr Emma Taylor talks about the causes behind an accident that happened during testing on a city metro system. Checks from the V-model that should have been applied during the development, testing and implementation of the complex, software-based system.
02:04 Using the V-model to verify and validate the integrity of safety-critical software systems.
03:10 The signalling failure incident and the major changes that were being tested.
04:43 The system definition step in the V-model—opinion on some assumptions made about the dependability of the core software.
05:16 Latent software faults.
05:50 Risk assessment, identifying hazards, and designing software systems to avoid them.
07:25 Some personal thoughts on why a data synchronization issue might have been missed.
08:15 The practical stages of software development, system requirements, and recording design changes.
09:20 Failure of data copying between systems, and related process documentation.
10:22 The testing part of manufacture—verification and validation throughout the lifecycle.
11:38 The role of third-party, independent assessors in the development process.
Resources mentioned in this episode:
The V-model on Geeks for Geeks.org: https://www.geeksforgeeks.org/software-engineering-sdlc-v-model/
The V-model for humans on Wikipedia: https://en.wikipedia.org/wiki/V-Model_(software_development)
Loss of safety critical signalling data on the Cambrian Coast line, 20 October 2017: https://www.gov.uk/raib-reports/report-17-2019-loss-of-safety-critical-signalling-data-on-the-cambrian-coast-line
The digital bits of a system podcast https://www.orr.gov.uk/guidance-compliance/rail/health-safety/strategy/rm3
Other related resources:
LHSBR Infrastructure Asset Integrity section: https://www.rssb.co.uk/safety-and-health/leading-health-and-safety-on-britains-railway/infrastructure-asset-integrity
LHSBR Rolling Stock Asset Integrity section: https://www.rssb.co.uk/safety-and-health/leading-health-and-safety-on-britains-railway/rolling-stock-asset-integrity