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KYT
17th Oct 2018, 14:17
Hi all,
Could anyone give me an idea about the specifics of gas pipeline inspection flights in the UK?
Interested to know how often an area gets inspected, how high and fast you fly, do you need to hover and if so, for how long. Also, what lasers, radar or anything else you use to detect methane etc, not tech spec but general info.

Thanks

MightyGem
17th Oct 2018, 19:42
I believe that they are inspected about every 6 weeks. More to check that no one is doing any sort of construction work over the pipeline than anything else.

KYT
17th Oct 2018, 19:54
Thanks, I’ve found they use LIDAR, laser radar to detect leaks. Wonder how high or low they go?

MikeNYC
18th Oct 2018, 01:03
Thanks, I’ve found they use LIDAR, laser radar to detect leaks. Wonder how high or low they go?
LIDAR's really not used for leak detection. LIDAR primarily is for mapping, generating a point cloud of the surroundings for later analysis. Some leak detectors use lasers, but those require the helicopter to fly through the leak plume, and the plume interrupts the laser beam between the emitter and detector, both on the detecting unit, enough to generate a reading

Leak detection is mostly done with Infrared cameras tuned to the proper wavelength, such as certain FLIR units.

KYT
18th Oct 2018, 06:43
Thanks Mike, and would you know the sort of heights and speeds used? And whether the helps hover much while surveying?

meleagertoo
18th Oct 2018, 10:28
Thanks Mike, and would you know the sort of heights and speeds used? And whether the helps hover much while surveying?
We used to do ours fortnightly on an exemption to 200ft and at a notional 80Kts. Hover is of no particular use - you can orbit if needed for a closer look. Landing out was only ever in extreme cases (A Hymac actually found digging on the easement for instance) In reality of course it was flown as fast as you could go.

aa777888
18th Oct 2018, 10:29
Someone gathering data to support a noise complaint?

OvertHawk
18th Oct 2018, 10:32
Someone gathering data to support a noise complaint?

More likely trying to figure out if he can do it with a fixed wing instead.

meleagertoo
18th Oct 2018, 11:41
Someone gathering data to support a noise complaint?
There have been precious few gas pipelines dug recently so any noise is an established thing.
The inspections are a legal requirement.

I think you'd struggle with a noise complaint on that basis.

f/w really isn't a good alternative. Visibility is so much poorer unless you're in an Optica it just won't work, flying at 200' downwind in half a gale isn't safe f/w territory. Grubbing over hill and dale in 1500m vis (ahem, at least!) and drizzle is most cetainly not.

aa777888
18th Oct 2018, 15:03
More likely trying to figure out if he can do it with a fixed wing instead.
Or with a UAV, in which case the answer is, of course, "Yes."

Our local police departments give public notice of scheduled utility inspection flights so as to cut down on nuisance calls. There's been more than one notice of "drones" instead of "blue and white helicopter" lately. It's happening.

KYT
18th Oct 2018, 16:05
It’s because some bright spark wants to build a new housing estate over the top of a mains gas pipeline, 900mm bore and 80 psi I believe. They have to give it 15 m spacing or so, either side, but I think it won’t go ahead for obvious reasons. Remembered from my time in the RAF, we had to avoid the inspection routes if we were low level, just thought a bit more ammo against the planners. The helos could hardly do inspections over a built up area, esp single-engined, 1000 agl min over built up I’ve been told.

Thanks for for the input folks.

MarcK
18th Oct 2018, 20:21
Show the public this report of a gas pipeline explosion in San Bruno, California (https://en.wikipedia.org/wiki/San_Bruno_pipeline_explosion)

KYT
19th Oct 2018, 07:42
Ouch that looks bad, thank you. I would think even the most stubborn Councillors will pay attention to this.

gasax
19th Oct 2018, 08:21
I work in the technical safety area and 15m is nothing like far enough for the pipeline you describe. Make sure the council insist on some gas dispersion modelling being done - no way I would live that close to to a threat like that.

roybert
19th Oct 2018, 13:36
More likely trying to figure out if he can do it with a fixed wing instead.

Pipeline patrols in Alberta Canada are carried out with a fixed wing aircraft. I know of one company that uses a red Cessna 172 to do the checks around Edmonton.

Roybert

KYT
19th Oct 2018, 16:16
Thanks again esp gasax, gives my Micky Mouse Council something to think about!

Self loading bear
19th Oct 2018, 17:01
80 psi is about 5,5 bar
in the Netherlands pressure in Main transport pipe network is 50 to 80 bar
so approx 800 psi.

SLB

rotornut
20th Oct 2018, 12:05
Pipeline patrols in Alberta Canada are carried out with a fixed wing aircraft. I know of one company that uses a red Cessna 172 to do the checks around Edmonton.
The Enbridge pipeline that goes through my land southeast of Edmonton uses a Piper Aztec (I think) that passes over once a week. The underside of the wings is marked in big letters PIPELINE.