Me too. Never been a depressurisation in an airliner due to a lightning stri
ke that I know anything about, and that hole is half the size of one of the o
utflow valves. The way the paint has been removed, and scorched.....hmmmmm, v
ery sus.
Tony R.
Sent from my iPad
> On 13 Nov 2014, at 4:50 am, Ivan Shaw <ivanshaw@btinternet.com> wrote:
>
> I don=99t think that this photo is a lightning strike!!!
> Ivan
>
> From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-ser
ver@matronics.com] On Behalf Of Pete Lawless
> Sent: 12 November 2014 17:42
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Re: Electrical bonding
>
>
> Hi Guys
>
> I sobering pic of lightning damage to a fully bonded all metal aeroplane -
I suspect in a Europa it would ruin your whole day!
>
> Plus an interesting Boeing article. http://www.boeing.com/commercial/aerom
agazine/articles/2012_q4/4/
>
> Regards
>
> Pete
> G-RMAC #109
> <image001.jpg>
>
> On 12/11/14 17:24, davidjoyce@doctors.org.uk wrote:
> Peter, Thanks - absolutely no apologies needed - it is very pertinent! I h
ad pored over this in great detail when preparing my Oz trip! Both in this a
nd in the other GRP glider strike quoted the lightning ran from wing tip to w
ing tip, with arcing causing enough heating/shock wave to break open or dela
minate the wing. It was very much because of this report that I hoped to pro
vide a more attractive (both to me and the lightning) path running essential
ly outside the wing. Regards, David
>
>
>
>
> On 2014-11-12 16:07, PETER MORGANS wrote:
>
> Hi David,
> Apologies for diving in on this topic.
> You may be interested to read AAIB Bulletin 12/99 (attached pdf) regarding
the disintegration of Schleicher ASK21 over Dunstable. Back in my gliding d
ays in the late 1960's it was mandatory for all gliders which held a B.G.A c
loud flying category to have electrical bonding. I think the answer is to st
ay away from large Cu unless you have a parachute.
> The following link, ref. this accident, also shows photographs of damage:-
www.pas.rochester.edu/~cline/.../ASK%20accident%20report.htm
> It's sobering to look at the damage to fittings.
> Regards
> Peter Morgans G-CFKZ Trigear XS
>
> From: "davidjoyce@doctors.org.uk" <davidjoyce@doctors.org.uk>
> To: europa-list@matronics.com
> Sent: Wednesday, 12 November 2014, 14:00
> Subject: Re: Europa-List: Re: Electrical bonding
>
>
> 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 l
ightning protection for the Airbus series did not produce clear answers and m
y memory of the Europa lightning strike account is that there were burn mark
s 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 a
ileron controls or wing light wiring to conduct it. Having been in a tram st
ruck by lightning in my youth and lost a neighbour to a lightning strike, I a
m not at all keen to go anywhere near a cu nim, but a large proportion of th
ose flying 'VMC' from UK to Australia have been unintentionally caught in el
ectrical storms. I did not imagine I could make my plane immune to damage bu
t just to lessen the likelihood of control run welding or instrument burn ou
t.
> Regards, David G-XSDJ
>
> On 2014-11-12 13:17, rampil wrote:
>
> Bonding together small bits of metal inside a sea of plastic insulator wil
l
> 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 infiltrat
e.
> 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 engine
er, I would also have to say, I can not see any benefit to bonding wingtip t
o
> wingtip, etc. The goal can not be to conduct a strike - you can not! Rath
er,
> the goal of bonding to discharge wicks is to bleed off areas of air fricti
on
> 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
>
>
>
>
>
>
>
> ectric.com
> ">www.buildersbooks.com
> builthelp.com
> lotstore.com
> m
> .matronics.com/contribution
> ttp://www.matronics.com/Navigator?Europa-List
> ics.com
>
>
>
> www.aeroearget="_blank" href="http://www.buildersbooks.com/";>www.build
ersbooks.c* My Pilot Store www.mrr --> http://www.matronics.com/Navigator?Eu
ropa-List=========
>
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