X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 07 Jan 2013 13:45:17 -0500 Message-ID: X-Original-Return-Path: Received: from elasmtp-scoter.atl.sa.earthlink.net ([209.86.89.67] verified) by logan.com (CommuniGate Pro SMTP 6.0.1) with ESMTP id 5999526 for lml@lancaironline.net; Mon, 07 Jan 2013 13:39:26 -0500 Received-SPF: none receiver=logan.com; client-ip=209.86.89.67; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=JC14PVnQXqAzQsIOoFjQhbieXAFFjm81ON/GJjnKgB6TtKS75jzv4TCHjh5SBvZ7; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [70.105.250.129] (helo=[192.168.1.34]) by elasmtp-scoter.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1TsHas-00075v-QY for lml@lancaironline.net; Mon, 07 Jan 2013 13:38:43 -0500 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-22--827883163 Subject: Re: [LML] static discharge X-Original-Date: Mon, 7 Jan 2013 13:38:42 -0500 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: <82FB0563-89F7-45E5-AA6E-A1991A2DF954@earthlink.net> X-Mailer: Apple Mail (2.1084) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940764c702c3a54145e7216411b818fdfc6350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.105.250.129 --Apple-Mail-22--827883163 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Ralf, I'm not clear exactly what you did. ...but the question of interest is = what's the resistance from the leading edge to the end of the wick? You = could have good continuity from the wick to the engine without having = good continuity from the leading edge to the wick. Issues along the way: - paint on leading edge leads to carbon very nearby. Could be a = problem if there is a lot of filler there. - bonding cable from trailing edge to aileron and another one to flaps = should be buried in conductive epoxy both ends. Different products = have variable performance. Ask Brad Simmons what he uses. - attach point of wick socket needs to be buried in conductive epoxy - non carbon surfaces should be coated with anti-static paint to lead = the charge over to the carbon part. (wing tips?) Colyn On Jan 7, 2013, at 1:26 PM, wrote: Dear subscribers, =20 In 2011 I saw some static discharge with missing paint nicks on the = leading edge of my wings when flying in the clouds. I added the Lancair = static wicks (2 on each aileron and 2 on each side of the horizontal = stab). When I installed them I used the metal bands to connect = everything together and get a good electrical connection back to the = engine/ground. I thought the problem was resolved. =20 On Dec 25th I flew the plane from cold Ohio to Orlando. There was a lot = of weather coming up from the south-west and I had to go out to the east = coast to get around the worst part. The usual under 3 hrs flight took me = 3.5 hrs on this day. At least 2.5 hrs during the flight I was IMC (in = the clouds, somewhat between unidentified layers, light rain etc.) I = started out at 17.000 and had to decent half way into the flight to = 11.000 because of too much ice on the wings. There were airplanes at = FL250 this day still IMC. =20 Below the freezing level in IMC I saw again some sparks off my leading = edge. Down in Orlando the wing did not feel charged when I touched it. I = had some minor paint damage on the leading edges again. On the way home = I was again for about 45 min IMC below the freezing level =96 I did not = see any sparks but the wing felt charged after landing. I found some = more paint damage. =20 When I checked the electrical connection first I did not get a signal = from the wicks to the engine. After I cleaned up the aluminum of the = wick on the outside I had the signal back to the engine. On one little = paint damage hole where I was able to see the carbon I tried to get a = signal back to the engine and I did not get a signal ( I did not want to = dig deeper or grind of paint so I left it alone). =20 I have some safety wire corkscrewed around my wicks and they are covered = with heat shrink tubing (to keep them from vibrating in flight) =20 I got silver metallic paint with clear coat on top. I did not use = conductive primer. To fix the little holes I put clear coat in the = little holes and wet sanded the leading edge again (I can still see the = little holes but at least I cannot feel them any more =96 assuming the = air flowing over it is blind anyway=85.) =20 =20 Question: did I miss something? Is there maintenance required on the = wicks? Or are there just situations where you can=92t help it and you = get static discharge? =20 =20 Thanks for your help =20 =20 Ralf =20 =20 --Apple-Mail-22--827883163 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Ralf,

I'm not clear exactly what = you did.   ...but the question of interest is what's the resistance = from the leading edge to the end of the wick?  You could have good = continuity from the wick to the engine without having good continuity = from the leading edge to the wick.

Issues along = the way:
- paint on leading edge leads to carbon very nearby. =      Could be a problem if there is a lot of filler = there.
- bonding cable from trailing edge to aileron and = another one to flaps should be buried in conductive epoxy both ends. =    Different products have variable performance.   =  Ask Brad Simmons what he uses.
- attach point of wick = socket needs to be buried in conductive epoxy
- non carbon = surfaces should be coated with anti-static paint to lead the charge over = to the carbon part.    (wing = tips?)

Colyn

On Jan 7, = 2013, at 1:26 PM, <bronnenmeier@GROBSYSTEMS.COM<= /a>> wrote:

Dear = subscribers,
 
On Dec 25th I flew the plane from cold = Ohio to Orlando. There was a lot of weather coming up from the = south-west and I had to go out to the east coast to get around the worst = part. The usual under 3 hrs flight took me 3.5 hrs on this day. At least = 2.5 hrs during the flight I was IMC (in the clouds, somewhat between = unidentified layers, light rain etc.) I started out at 17.000 and had to = decent half way into the flight to 11.000 because of too much ice on the = wings. There were airplanes at FL250 this day still = IMC.
 
Below the freezing = level in IMC I saw again some sparks off my leading edge. Down in = Orlando the wing did not feel charged when I touched it. I had some = minor paint damage on the leading edges again. On the way home I was = again for about 45 min IMC below the freezing level =96 I did not see = any sparks but the wing felt charged after landing. I found some more = paint damage.
 
I have some safety wire corkscrewed = around my wicks and they are covered with heat shrink tubing (to keep = them from vibrating in flight)
I got silver metallic paint with = clear coat on top. I did not use conductive primer. To fix the little = holes I put clear coat in the little holes and wet sanded the leading = edge again (I can still see the little holes but at least I cannot feel = them any more =96 assuming the air flowing over it is blind anyway=85.) =  
 
Question: did I = miss something? Is there maintenance required on the wicks? Or are there = just situations where you can=92t help it and you get static discharge? =  
 
Thanks for your = help