Of course it happened in my trigear Europa. I think it is one reason why gl
ider pilots always wear a parachute.
Date: Fri=2C 14 Nov 2014 17:54:38 +0000
From: davidjoyce@doctors.org.uk
Subject: RE: Europa-List: Re: Electrical bonding
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Karl=2C Was that in a Europa? I do not want to rabbit on endlessly but my o
wn plan had been also to link the engine frame to the tail spring of my mon
o in case the lightning came at me in that direction=2C Regards=2C David
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On 2014-11-14 14:53=2C Karl Heindl wrote:
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David=2C=0A
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There are always exceptions. When I was hit by lightning=2C or call it elec
trical discharge=2C in clear skies=2C it entered via the tailpipe and exite
d via the radiators. Apart from some melted metal there was no damage. I al
so have nav lights on the wing tips.=0A
It just illustrates that just staying away from cu nims is no guarantee for
avoiding a strike.=0A
Karl
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Date: Fri=2C 14 Nov 2014 10:49:26 +0000
From: davidjoyce@doctors.org.uk
Subject: Re: Europa-List: Re: Electrical bonding
John & Ira =2C With the greatest of respect for your professional electric
al & aeroengineering backgrounds=2C I think there are two rather different
issues here:
For certified commercial aircraft lightning protection standards s
eek to enclose all passengers and key aircraft components in a Faraday cage
conducting system that will cope with the fairly frequent strikes affectin
g commercial operations without any significant damage. To bring composite
aircraft to that standard clearly involves incorporating some conducting ma
terial in the entire surface of the plane and this is a nonstarter (or at l
east a non retrospective mod option) for a plane like ours.
The other issue is the possibility of minimising any damage to a pl
ane like ours in the event of a lightning strike=2C ( absolutely going alon
g with the assertion that it is much preferable to avoid it). There are thr
ee good accounts of fibreglass small aircraft strikes that I have come acro
ss and in every case lightning went from wingtip to wing tip causing signif
icant damage. These cases are the UK glider=2C previously mentioned (www.aa
ib.gov.uk/cms_resources/dft_avsafety_pdf_500699.pdf ) =2C another glider r
eferred to in that AAIB report of the first glider and the Europa strike su
ffered by Paul McAlister (www.sarangan.org/europa_forum/2004-08/msg00094.ht
ml ). In each case the pilot thought he was well clear of threatening cloud
s it seems. The gliders had the strike track along the aileron control rods
whereas with the Europa it tracked along the wing tip lights wiring killin
g a number of the avionics in passing. I would strongly recommend folk read
ing all these reports. Having personally done so I cannot avoid the conclus
ions that :
1. Getting struck by lightning is a real possibility for any sensible=2C c
autious pilot let alone someone contemplating flying through the ITCZ where
rapidly developing massive Cu Nims are endemic
2. Lightning can and will pass from wingtip to wing tip along the most ava
ilable conducting track
3. More debateable perhaps but my third conclusion was that there is much
to be said for offering a track that steers clear of vital structures=2C an
d in the light of this I had (in 2006) planned laying expanded aluminium me
sh in the wing close outs connected to aluminium foil over the wing tip and
to the rear lift pins/connecting rod. Nowadays I would no doubt use Alumin
ium Microgrid obtainable at modest cost from Aircraft Spruce. I would not
for a moment want to suggest that this would give commercial plane standard
immunity to damage=2C but that it would improve the chances of avoiding ei
ther the wing exploding or the loss of avionics or other key electrical sys
tems. I had toyed with the idea of static diffusers but without a system of
conducting static from other parts of the aircraft I was not convinced thi
s was workable ( and I guess that this non conductance of static is what sa
ves us from sparking when we touch ground - we are only discharging the imm
ediate area of contact.
Regards=2C David Joyce=2C G-XSDJ
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On 2014-11-14 08:42=2C John Wighton wrote:
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Ira=2C=0A
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You echo may own opinion on this subject. Fortunately my Europa does not s
eem to generate a lot of static (of a kind that can be detected at least).
There is not a lot that could be done if it did collect static whilst airb
ourne. =0A
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I had concerns about static build up and discharge on the ground=2C particu
larly whilst fuelling. I adopt the standard procedure of grounding everyth
ing to the same potential by touch=2C relying on terra firma to act as a gr
ound. So far there has never been the hint of a discharge even after a vig
orous polishing session.=0A
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Being involved in aircraft certification myself l am aware of the often hea
vy and costly solutions on larger aircraft. I am a structures signatory on
the A350=2C this has a high level of composites content and poses new issu
es and solutions on many fronts=2C including bonding and lightning protecti
on.=0A
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John Wighton=0A
Europa XS trigear G-IPOD=0A
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Read this topic online here:=0A
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http://forums.matronics.com/viewtopic.php?p=433644#433644=0A
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ectric.com=0A
">www.buildersbooks.com=0A
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ttp://www.matronics.com/Navigator?Europa-List=0A
ics.com=0A
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_blank">www.aeroelectric.com=0A
" target="_blank">www.buildersbooks.com=0A
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ank">www.mrrace.com=0A
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target="_blank">http://www.matronics.com/Navigator?Europa-List=0A
http://forums.matronics.com=0A
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ectric.com=0A
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ttp://www.matronics.com/Navigator?Europa-List=0A
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