Regular surveillance of transmission pipelines is required to comply with IGE/TD/1 and T/PR/MAINT/5, and forms a key protection measure within the National Grid Gas safety case. At present, surveillance comprises mainly of aerial patrols by helicopter (covering ~12,000 km every 2 weeks) plus some line walk and vantage point surveys. The latter are used where aerial surveys are not possible due to flight restrictions, flight cancellations and also for areas where third party damage poses a significant threat.
Helicopters have been the preferred method for performing the aerial patrols for many years. The helicopters operate at low altitude (generally around 500 feet) with an on-board observer looking out of the window and manually entering any potential threats into the SRP system.
Benefits
Key success criteria at the end of each stage are as follows:
Stage 1 Successful demonstration of the first iteration of algorithms and report
Stage 2 Successful demonstration of new / updated algorithms and report
Stage 3 Successful demonstration of new / updated algorithms and report
Stage 4 Report detailing the comparison between the current patrols and the new system.