X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 08 Apr 2013 14:40:14 -0400 Message-ID: X-Original-Return-Path: Received: from mail-gg0-f173.google.com ([209.85.161.173] verified) by logan.com (CommuniGate Pro SMTP 6.0.4) with ESMTPS id 6188508 for lml@lancaironline.net; Mon, 08 Apr 2013 13:17:55 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.173; envelope-from=pjdmiller@gmail.com Received: by mail-gg0-f173.google.com with SMTP id 21so910480ggh.18 for ; Mon, 08 Apr 2013 10:17:19 -0700 (PDT) X-Received: by 10.236.77.101 with SMTP id c65mr13348101yhe.192.1365441439703; Mon, 08 Apr 2013 10:17:19 -0700 (PDT) X-Original-Return-Path: Received: from [192.168.1.144] ([68.202.59.203]) by mx.google.com with ESMTPS id o64sm38476909yhd.16.2013.04.08.10.17.17 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 08 Apr 2013 10:17:18 -0700 (PDT) Subject: Re: [LML] Re: Fw: Static Wicks References: From: Paul Miller Content-Type: multipart/alternative; boundary=Apple-Mail-FAEDA210-70B0-4ECB-81A6-099410B1A36D X-Mailer: iPad Mail (10B146) In-Reply-To: X-Original-Message-Id: <9F7E38C1-8E12-45D3-84B3-D4077B53F01E@gmail.com> X-Original-Date: Mon, 8 Apr 2013 13:17:17 -0400 X-Original-To: Lancair Mailing List Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) --Apple-Mail-FAEDA210-70B0-4ECB-81A6-099410B1A36D Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Static wicks are for releasing charges to the atmosphere. That generally oc= curs at the pointy parts of the airframe that extend the furthest from the b= ody. Static will collect on the vertical stab but lots of aircraft have boo= ts 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 sur= face, then why do you place static wicks on it? >=20 > Sent from my iPad >=20 >=20 > On Apr 8, 2013, at 3:24 AM, "Frederick Moreno" wrote: >=20 >>=20 >> Static develops based on the impact of precip and ice crystals on the fro= nt (forward facing surfaces) of the airplane, that is, what you see if you s= tand way in front of the airplane and view it front on with a telescope. Th= is includes all the cowl, the front of the wings up to the thickest point of= the wings, windshield, etc. Behind the line where the curvature of wing, t= ail, and such hide the surface from impacting particles, static is not forme= d. The rudder is in this region. =20 >> =20 >> The number of static wicks required it dissipate static is based on a cal= culation of the frontal areas as described above (some percentage of thewing= area, for example, like 30-50%) and the speed of the aircraft.=20 >> =20 >> Normal Lancair procedure is to put static wicks on the trailing edge of a= ilerons, elevators, rudder with number as calculated by the wick maker. The= se must be connected to a conductive surface or wire, and this means wires i= n the rudder. Ideally, all carbon surfaces are bonded together with straps u= sing conductive epoxy bonded to the bare carbon fibers exposed by sanding, a= nd wires that go from control surface in parallel to the hinges so that ther= e is a continuous electrical path to be followed via wire (not hinge) in the= event of a big discharge that may pit a bearing. Anti static radome paint= works on the fiberglass cowl and vertical stabilizer carrying charge (letti= ng it leak away) to the carbon fiber or local ground and thence into the shi= ps ground. >> =20 >> In the end, a group of us concluded that it was best to run 10 gage groun= d wires to each corner of the airplane, bond all carbon surfaces to this gro= und net (that means top and bottom skins, control surfaces, etc.) and take t= he ground net to the main battery ground at the firewall so that the battery= serves as a pulse absorber which it does well. This level of connective bo= nding has eliminated static discharge problems on aircraft previously affect= ed. >> =20 >> Fred Moreno >> =20 >> =20 >> =20 >> =20 >> -------Original Message------- >> =20 >> From: John Barrett >> Date: 7/04/2013 11:02:53 PM >> To: lml@lancaironline.net >> Subject: Static Wicks >> =20 >> This question has to do with the rudder in the IVP. It=E2=80=99s written= that because the rudder is fiberglass, wicks aren=E2=80=99t effective due t= o non conductivity.=20 >>=20 >> =20 >>=20 >> A build shop installed wicks on my rudder and they ran ground wires to th= ose wicks from a/c ground. It seemed logical that this would make them usef= ul, but last night I had a discussion with Dan Newland who got involved in s= tatic discharge problems on a satellite project in his working days and he s= cratched his head at the notion. Said he wasn=E2=80=99t sure but would gues= s that the wicks are not going to be useful in that configuration.=20 >>=20 >> =20 >>=20 >> Anyone on the LML have knowledge that bears on the subject? I would like= to learn more. >>=20 >> =20 >>=20 >> Thanks >>=20 >> =20 >>=20 >> John Barrett, CEO >>=20 >> Leading Edge Composites >>=20 >> PO Box 428 >>=20 >> Port Hadlock, WA 98339 >>=20 >> =20 >>=20 >> www.carbinge.com >>=20 >> =20 >>=20 >> =20 --Apple-Mail-FAEDA210-70B0-4ECB-81A6-099410B1A36D Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Static wicks are for releasing charges= to the atmosphere.  That generally occurs at the pointy parts of the a= irframe that extend the furthest from the body.  Static will collect on= the vertical stab but lots of aircraft have boots which are conductive and t= he 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 t= rue about the rudder not being a forward facing surface, then why do you pla= ce static wicks on it?

Sent f= rom my iPad


On Apr 8, 2013, at 3:24 AM, "Freder= ick Moreno" <frederickmore= no@bigpond.com> wrote:

Static develops based on the impact of precip and ice crystals on the f= ront (forward facing surfaces) of the airplane, that is, what you see if you= stand way in front of the airplane and view it front on with a telescope.&n= bsp; This includes all the cowl, the front of the wings up to the thickest p= oint of the wings, windshield, etc.  Behind the line where th= e curvature of wing, tail, and such hide the surface from impacting particle= s, static is not formed.  The rudder is in this region.  
 
The number of static wicks required it dissipate static is based on a c= alculation of the frontal areas as described above (some percentage of t= hewing area, for example, like 30-50%) and the speed of the aircraft.  <= /div>
 
Normal Lancair procedure is to put static wicks on the trailing edge of= ailerons, elevators, rudder with number as calculated by the wick maker.&nb= sp; These must be connected to a conductive surface or wire, and this means w= ires in the rudder.  Ideally, all carbon surfaces are bonded together w= ith straps using conductive epoxy bonded to the bare carbon fibers exposed b= y sanding, and wires that go from control surface in parallel to the hinges s= o that there is a continuous electrical path to be followed via wire (not hi= nge) in the event of a big discharge that may pit a bearing.   Ant= i static radome paint works on the fiberglass cowl and vertical stabilizer c= arrying charge (letting it leak away) to the carbon fiber or local ground&nb= sp;and thence into the ships ground.
 
In the end, a group of us concluded that it was best to run 10 gage gro= und wires to each corner of the airplane, bond all carbon surfaces to this g= round net (that means top and bottom skins, control surfaces, etc.) and take= the ground net to the main battery ground at the firewall so that the batte= ry serves as a pulse absorber which it does well.  This level of connec= tive bonding has eliminated static discharge problems on aircraft previously= affected.
 
Fred Moreno
 
 
 
 
= -------Original Message-------
 
Date: 7/04/2013 11:= 02:53 PM
Subject: Static Wic= ks
 

This question has to do with the rudder in the IVP.&n= bsp; It=E2=80=99s written that because the rudder is fiberglass, wicks aren=E2= =80=99t effective due to non conductivity. 

 

A build shop installed wicks on my rudder and they ra= n ground wires to those wicks from a/c ground.  It seemed logical that t= his would make them useful, but last night I had a discussion with Dan Newla= nd who got involved in static discharge problems on a satellite project in h= is working days and he scratched his head at the notion.  Said he wasn=E2= =80=99t sure but would guess that the wicks are not going to be useful in th= at configuration. 

 

Anyone on the LML have knowledge that bears on the su= bject?  I would like to learn more.

 

Thanks

 

John Barrett, CEO

Leading Edge Composites

PO Box 428

Port Hadlock, WA 98339

 

www.carbinge.com<= /a>

 

 
= --Apple-Mail-FAEDA210-70B0-4ECB-81A6-099410B1A36D--