Electrostatic Electricity

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Hi, In my physics lesson earlier I was learning (supposedly) about electrostatic electricity and apparently in flight an a/c generates 1,000,000s of volts of electricity that circulate the skin of the a/c. He said that the first thing that happens when an a/c pulls up to the ramp is that it is earthed. Furthermore he claimed the fuel tankers do the same. I do not believe this - but if it is true please tell me. Thanks in advance, if anyone has taken GCSE Module exams in Science can you tell me what their like, im sh!ting myselfa about them, i got them next week, cheers, wozza
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Profile picture for user bmi-star

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Fuel tankers are earthed, as there is a severe risk of a spark from the static, created by the friction of the fuel rubbing against the pipe. Also there is static in mid-air, as on my SWISS MD-11 DVD, there is Elm's Fire on the windshield, where it looks like lightning is on the shield, but it is the static discharging! Looks amazing, but i'm frightened of thunderstorms, and i'd be very cautious if i saw that on my window! :eek:
Profile picture for user Speedbird 12T

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Of course static electricity build up, its the air rushing past and there are high levels of friction etc. Its like when you get out of your car, you sometimes touch it after being on a journey and youll get a shock, its because of the build up of static electricity. Also fuel tankers do use this because large build ups of static electricity can sometimes spark (bad for fuel tankers ;) ) So, they are earthed to let this static charge leak out. Dont worry me and my mate done the triple award, tests were really hard and we both came out with top results! Best of luck and wish for a hard test, because in an easy test you can make stupid mistakes AND the grade boundaries are high!

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Cheers for that, thanks for the confidence with the Exams, I'm also doing the seperate award,
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Ooooh GCSE's....i can't remember them now, you wait till you get to Uni, ooops better get one with those 3 assignments for tomorrow!! (Who said 1st year was easy???)
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I donĀ“t know how much static electricity (voltage) builds up on an aircraft skin during flight. My basic knowledge tells me it might be quite a bit, the total amount of static electricity must also be a variation of flight time and speed. But 1.000.000 volts will certainly never be present on the aircraft's skin at any one time. Reason is, that aircraft have so called Static Wicks at their extremities to get rid of the static while in flight. These Static Wicks look like short pieces of string (about 15 cm. long), and can be seen (usually) on the outboard ends of ailerons and elevators, and at the top of rudders. Regarding the grounding of the aircraft while on the ground, your teacher is right. If you look at the undercarriage of some aircraft you will see a kind of static wick touching the ground to transfer any residual static to the ground during landing. Also, all aircraft are grounded during refueling with an extra ground wire. That is because static can be generated in the fueling nozzle by the flow the fuel, for that reason the fuel truck/ground source is grounded, AND the aircraft as well just to make sure no Spark will be able to jump the gap between nozzle and aircraft, potentially causing fire.
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Just to back up your point galdi, heres a picture from A.net. Just wondering does this electricity just 'leak' into the air? http://www.airliners.net/open.file/620049/L/
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Yeah... definitely correct... wherever there is friction you will get some sort of electricity generated... I'm working as an electrician at the moment... and all gas and water pipes have to be earthed. The same is true of metal sinks... metal lightswitches etc... Dont worry about your GCSE's... they wont be that bad... I did the dual award science ones back in 1999... they were'nt that difficult... I didn't bother revising for mine! Wait till A-level and degree... then it starts getting hard! Good Luck anyway!
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good luck Warren - you'll be fine. I've got my GCSEs in June and not worried at all, but just do your best

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Thanks guys
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i think that's why some airlines, such as EasyJet and Jet2 which i've been on recently, put a barrier around the wing to stop you walking under it and they say "Don't walk under the wing".
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Aircraft Tyres have a metal strip on the inside which conducts the electricty generated away apon landing. Same applied to Helicopters as when someone is winching down from one they have a rod which has to tap the surface they are landing on before they do so that they become earthed.

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i think that's why some airlines, such as EasyJet and Jet2 which i've been on recently, put a barrier around the wing to stop you walking under it and they say "Don't walk under the wing".
They stop you walking under the wing because there might be de-icing fluid, Skydrol or eaven fuel dripping from the wing, passengers don't like being dripped on! Modern aircraft tyres are conductive so any electrostatic charge built up on an aircraft is discharged on landing. Fuel bowsers have conductive rubber straps dragging on the ground grounding them to earth. The bowser driver bonds the bowser to the aircraft with a bonding lead and the fuel hose is also conductive. The trick is to try and prevent any potential difference and thus any possibility of a spark near any fuel vapour. Rgds Cking Oh GCSE's?... be afraid, be very afraid!!!!!!!
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Also there is static in mid-air, as on my SWISS MD-11 DVD, there is Elm's Fire on the windshield, where it looks like lightning is on the shield, but it is the static discharging! Looks amazing, but i'm frightened of thunderstorms, and i'd be very cautious if i saw that on my window! :eek:
I've had St. Elmo's Fire twice in the last week thanks to the heavy amount of rain we've been getting. Very spectacular. I'm less worried about charges the aicraft produce than I am about charges from storms. ;)
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I'm in Jo'burg at the moment and as usual we had some fantastic St. Elmo's while overflying the storms at the ITCZ (inter tropical convergance zone) near the equator.
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I'm sure for you guys that is a spectacular feature, only you see! And the ITCZ is one very active and volatile band isn't wysiwyg, thats what i did my A-Level Geog Project on
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It's probably the most significant meteorological concern when doing a long haul north-south flight.