Safe Speed Forums

Happened upon this :
Shaken & stirred : http://www.bbc.co.uk/news/world-latin-america-17150747

and 'Electric' here : http://www.bbc.co.uk/news/uk-england-17128357

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.

Power lines have always been a problem for chopper pilots! The vibration of the machine makes them difficult if not impossible to perceive!

AIUI the way it works is this...

It is not physically possible to "See" a power line from any great distance (Especially the small "Telegraph pole" types which seems to be implied here). The image of the wire on the retina is just too small, what you "See" is a series of dots which your brain infers as a continuous line. the problem is that if there is a lot of vibration this series of dots become smeared out and the brain ends up discarding the data as random noise, the power line disappears. The trouble is that this disappearence doesnt occur in a manner that would lead the pilot to believe that his vision is compromised, everything else looks just fine (Trees, other land features, instruments, the co-pilot, etc) If he is not otherwise aware that a power line is nearby (Navigation data, spotting the poles, etc) then he is likly to fly streight into it only realising his error when it is too late to do anything about it.!

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"The road to a police state is paved with public safety legislation"

To the trained eye the large, closely spaced, transmission towers are a subtle indication of the presence and height of horizontal lines

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When I see an adult on a bicycle, I do not despair for the future of the human race. H.G. Wells
When I see a youth in a motor car I do d.c.brown

Pardonez moi- but I took Dusty's post as refering to those 40-50 foot poles, with LN& E strung out in country areas .Not so easy to see . And there's possibly quite a few higher woods, used as Rhombic masts for Highland & Island phone links (single channel VHF) left straddled about the West Highlands . Not exactly easy to see, as these were one offs .

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Gliders and ultralights seem to have a hard time seeing them as well.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

Wouldnt be at all surprised if Ultralights have similar vibration issues, and by the time a Glider pilot gets anywhere near a power line I would imagine that he is already so far up $hit creek that the loss of the paddle is unlikly to be an immediate issue any more!....

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"The road to a police state is paved with public safety legislation"

They claim that the equipment will indicate the cables so they ought to have known about them.
At least all the crew were OK !

I dare say in time we will hear more about it ...

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.