Lightning eats SSA Excom Minutes

Mike the Strike wrote:
From the latest SSA news:

"While I know this is going to sound like an excuse right up there with
"The dog ate my homework assignment..." last week the Carswell house in
Midlothian TX was struck by lightning (really).


Well, here in Tucson, we are sometimes known as the "lightning capital"
of America...and I have to tell you, we have a tree in the front yard
that was struck last year, while we were sitting in the house...sounded
like a terrorist bomb attack. The house shook, the power wavered off
and on, and the dogs went to hide. I firmly believe the story!

I have yet (lo, these many years) ever been able to recover a hard
drive from any power surge that great....sorry, I don't hold much hope!
Good luck.

micki minner

My mobile medical unit was struck by lightning while traveling on the
interstate near Junction, TX some years ago. The bolt struck the left
forward corner of the trailer and traveled forward to the tractor
wiping out the lights, engine computer, gauges, head, taillight and
marker bulbs and much of the wiring and rearward through the trailer
where the only damage was to the ceramic insulators in the x-ray
processor heater located at least 25 feet aft of the strike. The
trailer framing is steel so the charge apparently traveled through it
to the road protecting the x-ray equipment; the entire cab on the
tractor (GMC Astro), however is fibreglass and the wiring, gauges,
engine, frame rails and computer were the pathway. The driver was
badly frightened, but otherwise OK.

I'm mildly curious as to what pathway lightning might follow through my
carbon and glass fibre glider (not curious enough to experiment
however). Like Micki, I also believe the story.

Ray Warshaw
1LK


MickiMinner wrote:
Mike the Strike wrote:
From the latest SSA news:

"While I know this is going to sound like an excuse right up there with
"The dog ate my homework assignment..." last week the Carswell house in
Midlothian TX was struck by lightning (really).


Well, here in Tucson, we are sometimes known as the "lightning capital"
of America...and I have to tell you, we have a tree in the front yard
that was struck last year, while we were sitting in the house...sounded
like a terrorist bomb attack. The house shook, the power wavered off
and on, and the dogs went to hide. I firmly believe the story!

I have yet (lo, these many years) ever been able to recover a hard
drive from any power surge that great....sorry, I don't hold much hope!
Good luck.

micki minner

I'm mildly curious as to what pathway lightning might follow through my
carbon and glass fibre glider (not curious enough to experiment
however). Like Micki, I also believe the story.

Ray Warshaw
1LK



Vehicles are quite often struck by lightning and the damage varies from
nothing at all to (most often) damage to electrical and electronic
components, occasionally blown tires and (rarely) broken glass.
Lightning injuries inside vehicles are rare, but have been reported.

Damage to gliders depends on the current magnitude and duration of the
strike. Many gliders have survived weak cloud flashes with little
physical damage - I have personally examined two. The larger currents
of ground flashes can be more exciting as the arcs inside the glider
structure cause a large pressure pulse that can split a wing or blow
off the canopy. A severe positive ground flash blew a glider apart in
Britain a few years ago.

You may get a few warning signs when approaching an electrified cloud.
My Discus 2 produces small sparks from the release handle to my left
leg! Definitely a sign that you should fly somewhere else!

Mike

Mike the Strike wrote:
A severe positive ground flash blew a glider apart in
Britain a few years ago.

That was a K-21. The strike entered at one aileron push rod and traveled
to the other aileron push-rod, where it exited, through the spanwise
alloy push-rods and control linkage.

Ohmic heating in the control linkage produced a strong enough pressure
pulse to cut the fuselage in half and to blow out both canopies. The
skins were blown off both wings as well.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Martin Gregorie wrote:
Mike the Strike wrote:
A severe positive ground flash blew a glider apart in
Britain a few years ago.

That was a K-21. The strike entered at one aileron push rod and traveled
to the other aileron push-rod, where it exited, through the spanwise
alloy push-rods and control linkage.

Ohmic heating in the control linkage produced a strong enough pressure
pulse to cut the fuselage in half and to blow out both canopies. The
skins were blown off both wings as well.

Did the pilots report noticing any sparks, tingling, or other
"electrification" before the strike? I've had lightning strike within a
mile of my glider without noticing any signs of it, before or after.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric Greenwell wrote:
Martin Gregorie wrote:
Mike the Strike wrote:
A severe positive ground flash blew a glider apart in
Britain a few years ago.

That was a K-21. The strike entered at one aileron push rod and
traveled to the other aileron push-rod, where it exited, through the
spanwise alloy push-rods and control linkage.

Ohmic heating in the control linkage produced a strong enough pressure
pulse to cut the fuselage in half and to blow out both canopies. The
skins were blown off both wings as well.

Did the pilots report noticing any sparks, tingling, or other
"electrification" before the strike? I've had lightning strike within a
mile of my glider without noticing any signs of it, before or after.

No, nothing reported by either pilot. Additional support them not being
directly or indirectly affected is that the AAIB report says that only
the aileron control system showed signs of damage from the strike: even
the airbrake system showed no signs of electrical damage and probably
didn't carry any current.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

You must mean the ASK21 GBP which was destroyed near the London Gliding
Club, Dunstable on 17th April 1999.

The AAIB report may be found at
http://www.aaib.gov.uk/cms_resources...pdf_500699.pdf .

The pictures and other illustrations do not appear to be available, though I
have them, downloaded when the report was first published.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Mike the Strike" wrote in message
oups.com...


I'm mildly curious as to what pathway lightning might follow through my
carbon and glass fibre glider (not curious enough to experiment
however). Like Micki, I also believe the story.

Ray Warshaw
1LK


Vehicles are quite often struck by lightning and the damage varies from
nothing at all to (most often) damage to electrical and electronic
components, occasionally blown tires and (rarely) broken glass.
Lightning injuries inside vehicles are rare, but have been reported.

Damage to gliders depends on the current magnitude and duration of the
strike. Many gliders have survived weak cloud flashes with little
physical damage - I have personally examined two. The larger currents
of ground flashes can be more exciting as the arcs inside the glider
structure cause a large pressure pulse that can split a wing or blow
off the canopy. A severe positive ground flash blew a glider apart in
Britain a few years ago.

You may get a few warning signs when approaching an electrified cloud.
My Discus 2 produces small sparks from the release handle to my left
leg! Definitely a sign that you should fly somewhere else!

Mike

Sounds like the bonding strap may be broken on your pedals, or possibly
it was not replaced properly when the tow hook was serviced. Although
fixing this may make your early warning less effective, you will be
better off in the long run.

Mike the Strike wrote:

You may get a few warning signs when approaching an electrified cloud.
My Discus 2 produces small sparks from the release handle to my left
leg! Definitely a sign that you should fly somewhere else!

MickiMinner wrote:
Mike the Strike wrote:
From the latest SSA news:

"While I know this is going to sound like an excuse right up there with
"The dog ate my homework assignment..." last week the Carswell house in
Midlothian TX was struck by lightning (really).


Well, here in Tucson, we are sometimes known as the "lightning capital"
of America...and I have to tell you, we have a tree in the front yard
that was struck last year, while we were sitting in the house...sounded
like a terrorist bomb attack. The house shook, the power wavered off
and on, and the dogs went to hide. I firmly believe the story!

I have yet (lo, these many years) ever been able to recover a hard
drive from any power surge that great....sorry, I don't hold much hope!
Good luck.

micki minner
http://www.lightningsafety.noaa.gov/images/map.pdf shows the propensity
for lightning.

Florida has the most casualties, mostly on golf courses, but trails
behind many states in intensity.

The most intense storms I've personally experienced were in Nebraska
and Turkey.

Colorado has a lot of tornadoes, but tipping a shed or cow makes little
news.

Frank Whiteley