Thursday, 3 November 2016

National Grid helicopter

Jan and I went for another local walk yesterday. As we left the house we could hear a helicopter nearby. The noise stayed fairly constant, indicating that it was probably hovering. Air Ambulance? Police? We walked towards the sound and saw that the helicopter was neither ambulance yellow nor police blue. It was this, a National Grid machine.

It seemed to be gradually working its way along a run of transmission lines. Was it surveying the lines themselves? Or the pylons?

Or was it surveying the land for a new set of power lines to connect to a new offshore windfarm? These transmission lines have only very recently been upgraded (five years ago), as I wrote about here.

1 comment:

Halfie said...

Dave Ward comments:

Seeing that projection under the front of the helicopter I would guess it's an infrared heat seeking probe, and they are checking for any "hotspots" which would indicate potential faults. Looking back to your linked post, I believe the cylinders attached to the cables next to the insulators are harmonic dampers. These break up any standing waves that can occur in strong winds, which if unchecked could result in catastrophic failure. The helicopter is a Bell 429 - you can click on this link [] and type in RIDB to see more. At the bottom of the page are 2 photo links, which show the probe (if that's what it is) more clearly.

(Dave's comments never appear directly on my blog, for some reason)