Static discharge associated with C/L handles/flying

RknRusty wrote:

roddie wrote:Here's a GOOD read... I searched CEF and didn't find anything on this. We all should know NOT to fly in the vicinity of elec. power lines... but you can still get zapped from atmospheric electrical discharges... even if the weather isn't "immediately" or "noticeably" threatening...

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=385707&mesg_id=385707&page=

I read that some time back. I was surprised so many people had experienced being shocked. And most said it was in humid conditions, just the opposite of what I would have guessed. My Sullivan Insta-Just handle has enough metal in it to be susceptible. It'll probably happen to me while I'm flying in my upcoming contest.

Don't even "think" that Rusty.... 

Never even considered that. I'll let you know if it's true!  

Just kidding... Thanks for the info Roddie.

Ron

It used to happen to me all the time flying in Denver on summer afternoons.  The thunderstorms would roll in and you knew it was time to stop for the day when you pulled into a wingover and got zapped through the adjustment loop on the back of my EZjust handle.  Spent the rest of the tank flying level as close to the ground as possible holding onto the handle by your fingertips with your wrist at a ninety degree angle to get your palm as far away from the cables as possible.  Then packed up and got out of the park as fast as we could.

The storms didn't even have to be visible as clouds in sight.  Just the build up in the afternoon was enough.

The voltage gradient in the air can reach very high numbers, as much as several hundred volts per inch.  Think about having even fifty volts per inch and sixty foot lines, that's 36KV between your plane and you at the top of a wingover.  Breakdown of dry air is on the order of thirty KV per cm, so you can easily get a shock from those metal cables.

There was an article in some magazine of the time that took advantage of this gradient.  They had designed sensors for the wing tips and tail that measured the gradient and used it as an autopilot to keep an RC plane level, well at least level compared to the atmospheric gradient.

Jaye