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TC.RET
14th Oct 2005, 17:11
Recently a flight from Gerona to Bournemouth had a lightning strike and had to divert back to Gerona. What effect does a lightning srtike have on modern aircraft neccesitating it's immediate diversion?

Someone_Else
14th Oct 2005, 17:56
Could have fried the Nav equipment or caused some sort of eletrical problem.

Some bad strikes can cause structural problems, but I belive this is rare.

phnuff
14th Oct 2005, 19:53
I was a passenger on a KLM 747 going into AMS about 5 years ago when it was struck. My recollection was a kind of purple light, electrics being disrupted and nothing else. Oh, and this incredible feeling of being very close to a lot of energy

I loved it

captplaystation
14th Oct 2005, 21:00
Captain in this case was just being cautious.About 15 dodgy burned rivets was about it. As everything continued to operate normally he could have just as well continued to STN where maintenance was avail, but made instead the decision to return GRO for same reason.He was one of 3 strikes in GRO that day;engineering staff seem to feel 800 very prone to strikes,no-one knows why,but it really is.Similar thing in same vicinitya year or so ago resulted in a scorched/jammed alpha vane and false stick-shaker(not surprisingly he came back too!)but most common damage seems to be small holes/burns on skin,knackered rivets and a tell-tale scorch mark on trailing edge of starboard stabiliser,which seems to be the preferred exit point.Did see one last year with interesting little trails of molten metal on a leading edge but that(so far)is about all.There you go,nothing juicy there for the Ryanair-knockers,is there?By the way if you don't want to p*ss off the Catalans you better spell it GIRONA next time.

Ranger 1
14th Oct 2005, 21:30
A bit like this one phnuff.
http://www.thaivisa.com/forum/lofiversion/index.php?t44816.html

slingsby
15th Oct 2005, 09:00
Not a great deal of affect on an aircaft, sensible precaution to return if any anomolous readings or instruments flagged. Generally it passes along the on of the axis of the aircraft and exits through one of the static lines at the rear of the trailing surfaces. Popping of paint from rivets is a common result of a mild strike, heavier strikes tend to cause some electrical disturbances but nothing that isn't normally handled by the boards downstairs. The worst of all is a strike on the window wipers, damn it cra&&ed the life out of me while doing the crossword, huge flash and bang. Thats why we have flood lights on when near storms.

The video previous shows the entry somewhere around the cockpit, probably on or near one of the static tubes, and the exit on the left outboard elevator.

His dudeness
15th Oct 2005, 09:40
In our company, years ago a kingAir had a strike, entering the airframe via a propblade, leaving it via the wing. Result: no probs inflight, maintenance to planetary gear inside engine required. (hardened gear parts getting "soft" by the heat, I was told) Very expensive. Cheyenne was struck 3 times in a row and had just 3 little holes...
Neither cases showed any probs in avionics.
But another KingAir had a intermittend working GPS sensor, which was blamed to a strike.

wawkrk
15th Oct 2005, 13:00
A few years ago I was a passenger on an Ansett 737 waiting to depart from Sydney to Perth.
There was a severe electrical storm over the field.
The captain told us there were many delays and Ansett reported 7 lightning strikes. I assume Quantas had even more because of the larger fleet.
Is this a record for one day?

Flap 5
15th Oct 2005, 13:18
I have had 3 strikes on the A330 with no effect. It's just like someone has thumped the aircraft where it hits. One hit around the nose gear doors causing them to open and shut rapidly. Fortunately we were on the descent and were below 250kts, or the nosegear doors might have been ripped off!

Swedish Steve
15th Oct 2005, 13:23
Lightning strikes on transport aircraft rarely produce more than burnt rivets and missing static dischargers.
But there was a really bad one in ARN some years ago.
A DeutsheBA Fokker 100 was struck on rotation. The strike disabled both engine oil pressure transmitters. The ECAM (or whatever its called on a F100) called for L Eng Shutdown, and as soon as the crew had shut it down, R Eng Shutdown, which they didn't! It quickly returned when we replaced the transmitters and carried out the Lightning Strike Insp. This was a known problem according to TAT who were the maint organisation and had happened before.
The lightning strike insp on this aircraft was much more involved than any Boeing or Airbus that I have worked on. Usually you look for entry and exit points and if the crew have reported no problems then usually that is it. On a line station the damage has never been so great as to ground the aircraft.

Lost in Saigon
15th Oct 2005, 13:57
from http: www.answerbag.com

http://www.answerbag.com/c_view.php/508

There are only a handful of accidents on record due to a strike. Most notably was 08 DEC 1963 when lightening hit a Pan Am Boeing 707 directly on the fuel vent causing it to explode inflight. After that accident, the vents were redesigned and static wicks were required to be installed on aircraft.

These are the 13 accidents on record where ligtning was a cause or contributing factor:
http://aviation-safety.net/database/dblist.php?Event=WXL

Lightning strikes are more common than one might think. Statistics show that the commercial airlines average one hit per aircraft per year or an average of once every 1500 flight hours.

cwatters
15th Oct 2005, 16:17
I imagine that the metal airframe acts like a Farady cage and protects the contents much like the metal mesh suit this man is wearing. what about composite aircraft? Do they have a metal mesh layer?

http://hot-streamer.com/ross/Biggg/P2010007.jpg

Farrell
15th Oct 2005, 18:18
Is that Jerry Garcia kneeling down in that photo? :p

gengis
17th Oct 2005, 02:12
I had a lightning strike at about 13000 ft during a descent in IMC on a 777 which hit somewhere right of the radome. Up until that point, i used to harbour some doubts about how a new generation high tech, fully electronic airplane would really hold up in such a situation, notwithstanding all the flight testing that has been done. In this event, there was hardly a flicker on the flight instruments, both FMCs, AFDS panel, and most importantly, the fly-by-wire Flight Control Computers didn't even flinch! None of the avionics (radios, transponder, dme etc) were affected. I was a believer from that day.

Old Smokey
17th Oct 2005, 05:06
With the other respondants here, I agree that damage to the aircraft / avionics etc., is at worst minimal. In my experience a few pin holes and a lost ADF antenna were the worst cases that I've experienced.

An important aspect to flight safety is the effect upon pilot vision in the event of a strike in the proximity of the cockpit. In one strike close to the nose, both of us were blinded for up to 3 to 4 minutes. Thank God that the Auto-Pilot was engaged, and cockpit lighting was at maximum intensity. They don't call it the Thunderstorm Light for nothing.

Regards,

Old Smokey

fruitloop
17th Oct 2005, 13:01
Worst that i have seen is completly burnt out static straps and 2 welded bearings in a elevator ...737

Jetstream Rider
17th Oct 2005, 13:32
I have been hit on two occasions. First time was multiple strikes and the second time was a single strike. Both were just below the flight deck on the right hand side i.e. not far from my bum! God has missed twice - hope he isn't third time lucky!

First time we lost a generator which we reset, second time there were no problems at all. In the first instance there were some scortch marks and the second time no evidence at all except wide eyed cabin crew!!!

mono
20th Oct 2005, 10:17
Earlier this year there were several strikes on a/c on the same day at LGW. 2 a/c in particular (different airlines) suffered extreme damage to the Radome and more minor damage to the elevators.

Tha radome damage was so severe that at first I thought the a/c had suffered a bird strike until I realised there was no blood. There was a 10 inch hole in the front of the radome where (I think) the lightning earthed itself via the RADAR scanner rather that the diverter strips which were fractionally further away. Remarkably the 2nd a/c suffered almost exactly the same sort of damage.

prop jocket
20th Oct 2005, 21:20
Everyone says that lightning strikes are innocuous on modern aircraft. On the whole I would agree unless the aeroplane in question is a die by - sorry - FLY by wire machine.

The Air France Airbus didn't get off too lightly after a lightning strike! Word on the street ( originated by Airbus themselves ) was that all of the flight computers tripped/blew as a result of a total electrical failure. That beast ended up in three pieces.

Flap 5
20th Oct 2005, 21:55
See my post above. 3 strikes, A330, no effect (except nose gear doors opening and closing rapidly).

See also other posts above. Non fly by wire are equally or worse effected. :hmm: