lml@lancaironline.net Mailing List Archive

Sorry guys I couldn't resist. Paul's right and the most graphic illustration I've ever seen is enclosed. This is a NASA pilot in an F-106 modified and instrumented for thunderstorm penetration. Whenever it was struck by lightning, the cockpit aft-facing camera tripped. You can see that the lightning is shedding off the pointy tips of the delta wing and trailing down the vortex filaments, where the pressure is very low and the air ionizes easily.

Static is essentially the same thing. Static wicks are really pointy and you put them at the aft corners of the airframe.

Boeing did a similar study of unintentional lightning strikes and found that wherever the lightning first attaches to the airframe, it migrates quickly (milliseconds) to the aft edges.

On Apr 8, 2013, at 1:40 PM, Paul Miller wrote:

Static wicks are for releasing charges to the atmosphere. That generally occurs at the pointy parts of the airframe that extend the furthest from the body. Static will collect on the vertical stab but lots of aircraft have boots which are conductive and the area is not the same as cowls, wing tips and leading edges.

Paul

On 2013-04-08, at 12:54, John Barrett <2thman1@gmail.com> wrote:

So if the comment is true about the rudder not being a forward facing surface, then why do you place static wicks on it?

Sent from my iPad