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Married a Canadian 4th Apr 2006 14:40

Lightning strikes
 
Poor weather in Toronto yesterday and quite afew aircraft were getting struck by lightning. Poor BA and Air France got multiples!

I have never been on an airline when it has been struck. I know that all modern airliners are equipped to deal with it but from a cockpit perspective I would be interested to know what happens when you are struck?. Lights flashing, instruments flicker etc etc.

How accurate is the weather radar in cockpits nowadays?

Just curious

mcdhu 4th Apr 2006 15:37

....in my limited experience of (3) lightning strikes, all you really notice is a VERY LOUD BANG !!!!

Cheers
mcdhu

LastCall 4th Apr 2006 16:51

Lightning Strikes
 
Was in the second spin in the OCK hold at FL090 one morning last October. The conditions weren’t the best, as we were holding in towering CU with heavy rain and continuous moderate turbulence. It wasn’t very comfortable. As we started the turn back to OCK from the south end of the hold the F/O read my mind and stated, quite prophetically, that the conditions were about right for a lightning strike.

No sooner were the words out of his mouth when there was a bright flash on the left side and the immediate clap of very loud thunder, which drew my immediate attention to the screens & instruments. Not even a flicker! Everything continued normally.

It didn’t surprise us too much as we were both expecting it. I think it would have been quite spectacular had it been at night.

Inspection on the ground revealed a bit of scorching at the strike point on the left engine intake cowl, with the exit point at the aft end of the engine. Otherwise, no damage and no adverse instrument effect.

As far as the radar goes, it is very accurate for rain. But in a small space, like in a hold and the immediate approach area, you tend to use the short ranges which are going to show the rain to be everywhere, so it isn't going to tell you what you don't already know. Also, at the short ranges, like 20 miles and less, the radar tends to be overly sensitive and in a lot of cases makes things look worse than they really are. It's best used on the medium to longer ranges for weather avoidance.

Human Factor 4th Apr 2006 16:52

I got struck out of YUL at night a few months ago. Huge bang and all the screens went to full brightness. Otherwise ok, until we got to the Atlantic and found none of the HF radios worked!! CPDLC and Satcom got us across and we found a large scorch mark just below the flight deck on arrival.

Dani 4th Apr 2006 17:23

All the above is correct. The problem is that lightning also can happen outside of a thunderstorm cloud or propagate from inside to the outside.

The results of a lightning strike can be manifold, from nothing happening to holes in the structure to instrument and other components failure. The complete instrument failure can happen, but it is rare, and according to my observation rather happened on the last generation electro-mechanical generation than on the latest gadgedery.

I had one a multiple lightning strike on a turboprop and after the flight it showed that the lightning entered the cell, exited and reentered again, thus producing three holes in the upper left front fuselage. Those holes can be from tiny to one or two centimeters in diameter (that's up to an inch). But surprisingly the cabin pressure isn't really an issue, because the bleed system can provide more pressure than air is leaking.

Interesting lightning strike had been observed when lightning entered the cockpit and/or cabin and generated some light shows.

Dani

tilewood 4th Apr 2006 18:26

I was in a Canadair CL44 turbo-prop freighter enroute from Lagos to Kano in the 1970's when we were struck one night.

St Elmo's fire turned the windscreen laminate into a mass of purple veins,
like a leaf, and the tips of the propellers looked like Catherine Wheels!

When we arrived at Kano and did a walk round there was a small hole
in the skin near the base of the fin. Apart from that the aircraft was
fully serviceable, and it did not affect the integrity of the pressure hull.

The turbulence was interesting though!!

skywerd 4th Apr 2006 18:50

Don't look now, but the ERJ that I fly is very susceptible to lightning strikes. The company for which I work has had numerous lightning strikes.
On the ERJ, instruments are often affected, holes are left in the nose,tail and sometimes the wing.
Several of our aircraft, after being struck by lightning, had constant static in the radios. On further inspection, it was found that the static wicks were burned to a veritable crisp.
The worst scenario, however, is one in which the elevator cables weld to the frame of the aircraft. We have had two aircraft do just that.
Rumor has it, however, that each of our aircraft, just prior to being struck, were in the following configuration:
1. Down low and slowed down for turbulence.
2. Radios began to "crackle" and "hiss" (all ERJ pilots know what I am talking about).
3. The smell of ozone came, then the "big bang."
The loud bang was so loud in one aircraft that the flight attendant, who was sitting in her jumpseat at the time, had an ear drum rupture.
So much for lightning strikes being benign.
Somebody help me get on with CX....:sad:

Human Factor 4th Apr 2006 19:10

Forgot to say, we lost about half a dozen static wicks...

nostep737 4th Apr 2006 19:49

Man thats hurts
 
Last year going into BKK on a dark night with to much traffic to go around the red wall of death so through we went, we had vertical lighting all around then one big flash (luv the smell of ozone) a big flicker and my symbol gen fell over then suddenly it wasnt fun any more, got through and landed ok and on looking found we had being hit in the engine cowl put a nice big hole in scary stuff, I think a common place for 737's

Greenfinch 4th Apr 2006 21:55

Been hit a few times - no big deal, just a bright flash and a bang (one was pretty loud, but had a couple that were just a dull 'thud'.

That said, I once saw the wreckage of a glider that was hit - it peeled open like a banana and the alloy aileron pushrods were just lumps that had been completely melted ! (luckily the 2 crew had parachutes and escaped with minor injuries and brown underpants !!!).

steinycans 5th Apr 2006 07:33

http://www.pprune.org/forums/showthr...ight=Lightning

phnuff 5th Apr 2006 09:01

From a passenger perspective, I was in cattle class on a KLM 747 combi which got hit about 10 minutes before landing at AMS. There was an intense purple light in the cabin, a slight bang, the lights flickered and it was over (for us) although for some reason which I cannot explain, I got the feeling of being near a lot of energy. The Captain announced that there had been a lightning strike and not to worry

(I love the video above btw)

Lou Scannon 5th Apr 2006 09:09

I once got struck in a Fiat car at 8,000 feet over the Central Massif!

Well actually, I was sitting in the car that was in the back of a Hastings when that took the strike. I went back up on the flight deck to find one chap who had his helmet off sitting there with his hair standing on end, a smell of sulphur and the compasses spinning round.

Fortunately the trailing aerial had been wound in so there was not too much damage to the signallers kit (or the siggy) and we had one VHF set still working. Paris and London gave us compass less guidance and we continued to a landing at Lyneham.

The aircraft was bonded but not as well as they are today.

One more amusing fact. In those days the ops manual stated that when freighting it was a good idea to fly into the odd Cu-nim to give the pilots practice at turbulence flying!

Rainboe 5th Apr 2006 09:52

At 17000', 747 descending into BDA in heavy cloud, a stream of not brilliant lighning appeared coming through the cloud dead ahead streaming straight to the aeroplane. It must have lasted about 6 seconds or more. We had that funny atmosphere you get- our hair was standing on end because we were really scared- it looked at if it was heading straight between each of our knees. Ended with a very big flash and bang. I simultaneously felt something like a flick on my watch, which was new and rather expensive, but undamaged. That was one of the unusual strikes. Lots of flashes and bangs and holes made, but the scary stories are the ones about ball lightning appearing in the cabin and wandering about for many seconds. Still nobody knows anything about them. A prize for the first guy with the guts to stick a finger in one!

Elroy Jettson 5th Apr 2006 09:54

Watched a great doco on Discovery channel about sprite lightning. Google it or check this out. http://www.newscientist.com/channel/earth/dn8733.html.

They think designers will have to rethink how much energy will have to be dissipated through bonding...

They are attributing it to a number of previously unexplained hull losses. One of them a Pan Am B707!

Interesting stuff!

Anyone seen ball lightning cruise down the cabin? Or is that the aviation yeti equvalent?

(Holding inside towering CU? Seriously? :eek: )

Mod Flight 1 5th Apr 2006 13:37

I remember a 747 taking off from Heathrow that got struck. The crew saw some fluctuations in the engines and a bang. Everything seemed normal. Landing in Toronto the lead noticed something and advised the captian.

There was a 2 foot dent in the nose from where they were struck.

:ooh:

Tired Old Man 5th Apr 2006 13:39

Lightning & ball lightning are very complex phenomena see link for some interesting information.

http://www.amasci.com/weird/unusual/bl.html

Regards

Frangible 5th Apr 2006 15:29

Metal a/c seem to do well with lightning. But what about composites? AAIB report into a Super Puma ditching -- lightning strike caused a composite tail-rotor blade to fail -- suggested that lightning protection standards were set way too low because the failure occurred at an unexpectedly high charge, four or five times higher than the max envisaged in the standard. Then and now, there haven't been enough lightning encounters with planes with a high proportion of composites to see this work out in real life. The current standards may be good enough for metal, but possibly not for composites. Interesting question for A380 and B787.

Rainboe 5th Apr 2006 16:05

Elroy, I knew a steward who swore to me this story was true. He and a stewardess were sitting in the rear vestibule seats of a VC10. They're by the door right back between the engine intakes, so very noisy. Night, seat belt signs on, turbulence, facing rear, trying to hold a conversation. Around the bend next to his shoulder a ball of lightning had come down the cabin, gently around the bend and floated gently past them at shoulder height, heading towards door, moving very slowly. It then passed through the door and disappeared. Very funny atmosphere, hair on end (it would be!), stewardess hysterical, unable to swallow. Several other similar incidents known over the years in BA.

ALLDAYDELI 5th Apr 2006 16:15

I heard a similar story on the BA285 B747-200 going LHR-LAX back in late 90s.
I watched it take off and saw it get struck by lightening somewhere Slough direction. Pax in question said the flash entered the cabin forward and exited rear. I didnt see that bit.

captjns 5th Apr 2006 19:19

The two lightening strikes I've experienced started with a hiss increasing in volume followed by a loud report. On resulted in a 2" hole in the horizontal sabilizer which drilled a hole in the hinge plate. No loss of generators or inerruption of nav/comm resulted in either strike.

JW411 5th Apr 2006 19:35

We have had this conversation before on a previous thread but I have sat through a ball lightning event once about 40 years ago over the Massif Centrale at night.

The ball appeared on the flight deck went downstairs and worked itself backwards through the cabin and exited the aircraft to the rear.

No damage was done apart from several underpant changes but I remember the dust and general crap that had been lying around for years behind the instrument panel suddenly being in suspension.

Afterwards, the loadmaster was quite adamant that he saw the ball come down underneath the wing and enter the aircraft.

JackOffallTrades 6th Apr 2006 00:04

Got struck once. Climbing through fl70 between two cells. Thought we had lots of clearance from them both. Wasn't expecting it. Big bang and a flash. Incredibly bright, it went in infront of my windshield and out the elevator trim tab. Since then I've been alot more cautious around cbs.

perkin 6th Apr 2006 17:57

I'm not a professional here, but I was pax on a flight that was struck by lightning on the approach to Gatwick in December of all times, while flying through a very heavy shower...Seemed to strike the fuselage just ahead of where I was sitting (or does it pass along the fuselage, giving the effect of it striking ahead of my window? I'm not too sure of the mechanics/physics of lightning strikes) and there was just a very loud 'crack' and obviously a nice flash too. Didn't seem to be a particularly big deal, but made a few fellow pax go a bit quiet...! It certainly gave the 737 a fair old thump which I felt through the floor...An interesting experience!

outoftheblue 6th Apr 2006 20:50

A little bang....
 
PAX on BA 737 EDI-LHR February 2001 on downwind leg to 9L. Lightening hit nacelle directly outside my window. Deafening bang that was over v.quickly and wing lit up green which would probably have been quite pretty but I was contemplating my imminent death.
Captain came on straightaway and said that some of us might have noticed a little bang (a little bang! It probably was up the sharp end!) but a plane was the safest place to be when lightening strikes and we would be landing in 5 mins.
As we turned onto what turned out to be a short final we got hit again! Everybody was anxiously awaiting the reassuring tones of the Captain but none came. He had his hands full with the landing and we all had white knuckles!!
:eek:

haughtney1 6th Apr 2006 23:15

B757 on descent into Murcia last summer...Id literally just said to the Capt that the CB's we were dodging around seemed very tame.....then BANG BANG BANG, three strikes in about 2 seconds..with the last one just below my DV window...various expletives then uttered..and umbridge paid to murphy :uhoh: :}

Capt Claret 7th Apr 2006 00:45

MaC,

I took my first known strike in Feb last year. The F/O was the pilot flying a BAe146-200 - analogue instrumentation.

Whilst completing some paperwork I noticed him duck. This was followed by a flash and an almighty bang. Once the F/O's heart started beating he advised that the lightning had struck the nose, near his windshield wiper post.

Sadly there was no damage to the aircraft or any of its components. It was a dog of a machine and whilst we didn't want it to fall out of the sky, we wouldn't have been at all sad if it was determined upon inspection, to be unsalvagable.

Oh, and after we'd landed and disembarked the pax, the F/As advised that they, and many of the pax had seen a fireball pass down the starboard side of the aircraft, outside not inside.

Ultralights 7th Apr 2006 01:07


Originally Posted by Capt Claret

Sadly there was no damage to the aircraft or any of its components..

:confused: :confused:


seeing as there is plenty of us who have experienced Lightning strikes, Ball Lightning, and St Elmo's fire, there surly must by some photos of such events?? i have never seen st Elmo's fire, but would love to see a pic of it!

Dan Winterland 7th Apr 2006 02:39

I've been struck several times and received shocks twice. The first was in a composite glider. There was no damage to the airframe but my left hand was on the airbrke lever and the charged arced from the metal part of the lever ovedr the plastic grip and hit my palm. I still have the scar today.

The second shock came in a VC10. I always thought that a metal airframe should a act as a farady cage and protect the occupants. Not so in this case. The strike was on the refuelling probe just above the radome. I was the PNF and was transmitting - telling ATC we were deviating for weather! The shock went throught the left pedal, up the left side of my body and through my left hand. The F/O felt a shock through both feet and lightning path went through the centre of the cabin. Everyone was sitting down so no-one in the cabin was struck. The aircraft had holes in the refuelling probe and both wingtips. I get aches up the left side of my body, parcticularly in the left wrist and ankle.

kenparry 7th Apr 2006 14:13

I had only 2 strikes in 20+ years of airline flying.

First on a B737 going into NCL, about 6 miles finals, only moderate Cu around. No warning, big flash, big bang, as we got a strike on the nose just outside the FO's front window. No effect on the aircraft at all. We did find a small burn mark on the nose afterwards.

Second was on a B767, again on the nose, very similar.

For some years I monitored the stats of my (former) employer's fleet, and the rate was about 1 strike per airframe per year, utilisation being about 4000 hr per year.

Doors to Automatic 7th Apr 2006 14:28

Can commercial aircraft withstand a rare positive strike (as opposed to the far more common negative) as this is many times more powerful?

False Capture 7th Apr 2006 14:30

Ultralights,
Try this link:

http://www.airliners.net/open.file?i...v_id=&next_id=

airship 7th Apr 2006 14:38

Not a lot of people know this I'm told, but just before lightning strikes an airliner, the GPWS will often go off with a whoop whoop pull up... :O

(Hope it makes more sense here False Capture) :confused:

Farrell 7th Apr 2006 19:17

Lots of this phenomenon can be experienced around France at the moment :E

banewboi 8th Apr 2006 00:04

hi guys

i was involved in an incident over the mid atlantic, mid turbulence (the usual do) and everythin went quiet. there was a low pulsing purple light that went from front to back (767-300 series) really really slowly, like if you watched a flourescent tube come on from one end over 5 mins in slow motion and then it was gone.

scorch marks below flight deck and apu!

212man 8th Apr 2006 09:08

It can be fairly bad news for helicopters; composite blades, sharp angles at the tail rotor tips, lots of gear teeth to spot weld each other etc. My last company lost an aircraft shortly after a strike (tail rotor shook itself to bits) but the 18 POB survived the ditching, and another a/c lost a main blade that had been previously damaged (but cleared as serviceable by the manufacturer) in a strike. sadly, you don't survive blade shedding!:(

blue up 9th Apr 2006 07:17

Seem to remember an FO in the UK losing his medical after a strike hitting the side window and Btzzzzing him. Might (?) have read it in the Balpa mag years ago.

btw. 14 scorch marks on my 757 passing a single small cell at 12,000 over POS vor near Palma,Majorca. No night stop, though (bugger!)

Charles Darwin 9th Apr 2006 08:52

This is how it can hit you. Has some negative side effects on the weather radar :ugh: .
http://img107.imageshack.us/my.php?image=00000299xv.jpg

DC10RealMan 9th Apr 2006 11:17

I was a passenger on a flight on finals for LHR once. A load bang occurs when the aeroplane gets a lightning strike. The five year old boy in the row in front of me leaps to his feet and exclaims "**** me!, What was that!. The cabin was in uproar, but not his parents I hasten to add.

aidey_f 9th Apr 2006 18:27

There is an interesting AAIB report into a lighting strike on an Embraer ERJ here:

http://www.aaib.dft.gov.uk/cms_resou...RJXG_11-05.pdf

Potted version:
Looks like the hot air from the lightning discharge along the fuselage caused an EGT overtemp so the FADEC shut down the engine. An interesting report, particularly the recomendations at the back end.


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