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737-800 winglets

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Old 18th Aug 2010, 06:42
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737-800 winglets

hey all, i have a fleet of 737-800 with beautiful blends in my company.
but after one year operation, we found that this aircraft is much easier to get lightening strike compared to the -800 with no blends.
i am guessing is that because the -800 with blends has 2 static discharger on each wing tip? less than the -800 without the blends which it have 3 static dischargers on each wing tip.
do you have the same situation in your companies?
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Old 18th Aug 2010, 07:00
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Not that I know of, but then I don't think we get many lightning strikes.
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Old 18th Aug 2010, 10:08
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The -800's are damned lightning rods as far as I'm concerned.
Without doubt they get hit more often than any of our other types.
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Old 18th Aug 2010, 10:15
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I'll second that, but if I remember well they were just as bad before we started to receive/refit winglets.
In any case they are several scales worse than classic (300/400/500) in my experience, why? the engineers have no clue either , they just know that they are often called to patch/repaint burn holes.
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Old 18th Aug 2010, 11:04
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we fly airbuses with winglets,737 -800s and 747-400s and the -800 win hands down.I doubt it is winglet induced.They get hit all over the place.
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Old 18th Aug 2010, 12:31
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Search for it, but I asked the question a while ago about why the -800 wingtips do not have the static wicks on the their tips but on the end of the hard wing surface. I can't remember all the responses. Perhaps this has some effect.
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Old 18th Aug 2010, 13:00
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thanks a lot RAT , i`ll check that out~
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Old 18th Aug 2010, 13:18
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Citizensun,

It has nothing to do with the winglets. Also the static discharge wicks do not stop an aircraft from being hit by lightning as you allude to by the number of wicks. They merely provide a point of static discharge on aircraft (lightning being one instance of increasing the value of which) to atmosphere.

The placement of the wicks is all to do with the construction materials used in the manufacture of the winglets, and their ability to conduct electrical charges.

GB
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Old 18th Aug 2010, 13:44
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Hi,

Static wicks are not used for lightning protection, they are more to discharge static electricity, and can be used as good indications if airplane was hit by lightning.
Link

Static Discharge Wicks

Sorry jes realized, GB has already explained what my point was. My bad!
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Old 18th Aug 2010, 13:48
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GB thanks,
i was told the static charger discharging the static has two benefits,
one is it can reduce the interference with the radios etc.
the second is it reduce the electric potential difference on the aircraft surface,then reduce the possibility of being hit by the lightening.
i don`t know if it`s true or not, please shed some light on it~
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Old 18th Aug 2010, 14:05
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Correct, The wicks do discharge the continuous buildup of static electricity an aircraft generates moving at high speed, and assists prevent interference with the communication systems.

Many aircraft types have flown in similar weather and I can not explain why the NG seems to get hammered by lightning where others dont, but it does happen.

If point two was the case you would see a lot more wicks on modern aircraft.

GB
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Old 18th Aug 2010, 14:32
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good point~
thank you for your effort!
wish Boeing company will do some analysis on the 737NG , why there are more lightening striked on it....
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Old 18th Aug 2010, 16:35
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I seem to recall being told that there are some very specific geometric parameters - sweep angles, nose/tip/tail distances, and so on - which can significantly affect lightning strike rates. It may be that the 737-800 is one of the "unlucky" types which has hit the "sweet spot" for being a lightning attractor.
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