Ira, You may well be right and I am quite prepared to accept your
superior electrical training, but talking to British Aerospce engineers
involved in lightning protection for the Airbus series did not produce
clear answers and my memory of the Europa lightning strike account is
that there were burn marks at each wing tip and the strike had travelled
across the plane. That being the case, it seems to me to be a better
idea to have a path other than the aileron controls or wing light wiring
to conduct it. Having been in a tram struck by lightning in my youth and
lost a neighbour to a lightning strike, I am not at all keen to go
anywhere near a cu nim, but a large proportion of those flying 'VMC'
---From UK to Australia have been unintentionally caught in electrical
storms. I did not imagine I could make my plane immune to damage but
just to lessen the likelihood of control run welding or instrument burn
out.
Regards, David G-XSDJ
On 2014-11-12 13:17, rampil wrote:
>
> Bonding together small bits of metal inside a sea of plastic insulator will
> accomplish nothing except add weight to your airframe unless you
> have an array of static discharge wicks. No Europas I am aware off have
> them. The best thing for a builder to do regarding lightning strikes
> is to make sure there are no voids in the layups where water can infiltrate.
> The water will turn to steam and explode. Aside from that, Do not
> fly near Cu. If Cu are unavoidable, just remember: Flying IS avoidable.
> In this I respectfully disagree with David. As a former electrical engineer,
I would also have to say, I can not see any benefit to bonding wingtip to
> wingtip, etc. The goal can not be to conduct a strike - you can not! Rather,
> the goal of bonding to discharge wicks is to bleed off areas of air friction
> static charge back to the atmosphere, thus avoiding being an attractive
> nuisance for lightning.
>
> There is no such this as "earth" on a composite airplane. The only ground
> is the negative battery terminal. That's it.
>
> It's not a house! There's no neutral (white wire) and earth ground (green
> wire) dichotomy. Just make all grounds short, fat and tight.
>
> --------
> Ira N224XS
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=433500#433500 [1]
>
Links:
------
[1] http://forums.matronics.com/viewtopic.php?p=433500#433500
[2] http://www.aeroelectric.com
[3] http://www.buildersbooks.com
[4] http://www.homebuilthelp.com
[5] http://www.mypilotstore.com
[6] http://www.mrrace.com
[7] http://www.matronics.com/contribution
[8] http://www.matronics.com/Navigator?Europa-List
[9] http://forums.matronics.com
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