Using mobile phones while fueling

[ysababha]

Dear all members ,:ok:
first i would thank everybody here for the great informations they supplies,im new in here and really enjoy having all this knowledge.

my question is why its prohibited to use phones while the A/c is fuleing and is it serious risk for doing that ?
i know that the procedures mentions that but why ?
in technical words what would happenes ?
and why using PTT (push to talk) mobiles allowed while using GSM ones not?

[jpoth06]

Have a look here (http://www.pprune.org/engineers-technicians/145851-refuelling-cell-phone-use.html) :)

[con-pilot]

When you take into account of all of the possible ignition sources around an aircraft when it is being refueled, I would think the least likely source would be a low voltage battery powered cell/mobile phone.

To be honest I never given the use of using a mobile phone during refueling operations a second thought. You have the exhaust from the refueling truck, the APU exhaust, the hand held radios used by the re-fuelers, flight crews using the aircraft radios and then of course me walking around with a lit cigarette in my mouth.

Just kidding about the cigarette now, don't anybody have a coronary. :p

[sb_sfo]

At SFO, the fueling company prohibits their fuelers from using cell phones while in the refueling lift, but I think that's more to eliminate distractions/personal calls. It's sort of effective, but who knows? The outfit I work for prohibits pax on board when fueling, in most cases.

[Lightning6]

To be honest, I've never heard of any cases of mobile phones causing ignition of fuel when re-fuelling....But I stand to be corrected. And that goes for cars in petrol stations, never heard of any incidents.

[Leezyjet]

Just kidding about the cigarette now, don't anybody have a coronary

Never been to Spain then ?. Common occurance there, or certainly used to be to see the refueller sat in the truck with a fag hanging out of his mouth - not just the refueller either, but most of the other ramp tramps too !!.

:eek:

[john_tullamarine]

Kero based fuels probably are somewhat lesser risk - think back to Brabazon's little demonstration many decades ago in the kero versus widecut debate.

However, I have had a couple of reports over the desk from authoritative sources relating to automobile refuel fires attributed to mobile phone use.

For those who haven't observed a low flashpoint fuel catching fire .. it's an eye-opening matter ... and puts the whole thing in a different perspective.

[Graybeard]

I think petrol station fires are nearly always traced to static electricity, like from a woman in unnatural garments (not cotton or wool) sliding in and out of the car while refueling, then touching the nozzle.

In the early days of the KC-10A, transmitting on HF would cause the refueling boom to shake about. Turns out some bypass capacitors in the boom control computer, which was an MD-80 FGC, had some capacitors wired to couple, rather than bypass HF energy.

Everybody knows, of course, you aren't supposed to transmit on HF during refueling, which is prudent, considering the high currents involved with notch antennas, and high voltages with probe antennas.

Some people show concern about VHF, WX radar, etc., but totally forget the 500W peak DME transmissions.

GB

[Lightning6]

Yes Graybeard, I can understand that with HF transmissions, but how the hell do they prove a fire was caused by a pair of nylon knickers? Mobile phones don't produce a lot of power output (IMHO), which is why we have so many cells.

[rubik101]

Many years agom MAEL used to allow smoking in the hangar when mechs were working on the aircraft. However, watching eggs getting hard boiled when placed bewteen two mobiles calling each other is a whole new kettle of fish, so to speak. Look on youtube.

[Lightning6]

Many years agom MAEL used to allow smoking in the hangar when mechs were working on the aircraft. However, watching eggs getting hard boiled when placed bewteen two mobiles calling each other is a whole new kettle of fish, so to speak. Look on youtube.

You believe that!! I'm an ex-electronics engineer in the communications industry, whatever you have seen on youtube is false, give us a link, I can't be bothered to search for something I know is made up.

[call100]

Not Eggs....But Popcorn....Yes!!!
YouTube - Cell phone Pop Corn -Make pop corn pop with your cell phone (http://www.youtube.com/watch?v=jgjx4JROjR4)

[direct ortac]

It'a a hoax

Cell Phone Popcorn Hoax Revealed. - Video (http://www.metacafe.com/watch/1399627/cell_phone_popcorn_hoax_revealed/)

[Agaricus bisporus]

The company I work for allows pax to use phones while refuelling, but the nearest part of the grounded refuel rig is about 10m from the nearest pax and the other side of a pretty effective Faraday cage. Pax are not supposed to use phones on the ramp, tho no one bothers to stop them nowadays.

Whislt refuelling my C150 I was amazed to see the chap using a walkie-talkie clamped to the nozzle with the same hand! I told him to stop, pretty sharpish, and he claimed, vey huffly, that he'd never heard of any danger in fifteen years of refuelling!

Power output of a mobile phone is no more than several milliwatts, I doubt one could induce a spark if you tried in a laboratory. It does surprise sometimes that presumably technically trained people on this forum swallow such obvious hokum.

Cooking popcorn and eggs indeed! Heard the one about the moon and cream cheese?

[Rainboe]

Would appreciate some words of wisdom concerning static and refuelling aircraft with Mogas (car petrol). I understand (according to August Pilot) that it is NOT recommended to refuel aircraft with Mogas from plastic containers due to the possibility of static discharges. Does anybody know where this comes from? I can understand there may be a problem in dry and dusty Australia and Arizona, but Europe?

[call100]

Ah well! It was fun while it lasted.....;)

[con-pilot]

All kidding aside, I did witness a T-33 blow up during over-wing refueling because the aircraft was not grounded. Now the fuel was JP-4, which has a much lower flash point than Jet-A.

Well I actually did not see the actual explosion, I was standing around the corner of a hangar and saw a flash, heard the explosion and then felt the heat. When I did get around the corner of the hangar I saw what was left of one T-33 and two other T-33s on fire.

Nasty business that was. :(

[Graybeard]

.. how the hell do they prove a fire was caused by a pair of nylon knickers?

Typical scene: woman admits getting back in her car while it's refueling, then gets out and removes the nozzle, and the fire starts. We now have warnings at gas pumps to touch some metal part of the car before inserting or removing the nozzle.

Friction between certain insulators creates an electrostatic charge of up to 40,000 volts or more. Plastic loves to hold a charge. Plastic gas containers must be on the ground while being fueled. I recently hollered at a guy who was filling plastic gas containers while standing in the bed of his pickup with a plastic bed liner.

Same goes for refueling an aircraft from plastic containers. Everything must be brought to the same electrical potential, or ESD - a spark - will occur.

GB

[raffele]

Through a not very scientific experiment a programme in the UK called Brainiac proved that mobile phones don't cause fires/explosions at petrol stations.

They also proved that you can cause a very big fire/explosion through static electricity...

[Capetonian]

Ever seen the regional GM of an airline walking under the wing of an aircraft whilst it was being refuelled ...... bad enough ..... but with a lighted cigarette in his mouth? I have! (Again, no names ..... but I'd love to!).

When I confronted him he came out with the famous : "Do you know who I am?" As it happened at that point I didn't, but when he told me I made it very clear that he should :mad:ing well know better. I called the apron security to deal with him but the two guys walked off with a smile on their faces and slightly fatter back pockets! End of incident.

[Lightning6]

Typical scene: woman admits getting back in her car while it's refueling, then gets out and removes the nozzle, and the fire starts. We now have warnings at gas pumps to touch some metal part of the car before inserting or removing the nozzle.

Friction between certain insulators creates an electrostatic charge of up to 40,000 volts or more. Plastic loves to hold a charge. Plastic gas containers must be on the ground while being fueled. I recently hollered at a guy who was filling plastic gas containers while standing in the bed of his pickup with a plastic bed liner.

Same goes for refueling an aircraft from plastic containers. Everything must be brought to the same electrical potential, or ESD - a spark - will occur.



GB

Point taken, GB...Although that is the only case I've ever heard of, no such warning signs here in the UK, but, as you say, static electricity is not to be taken lightly, earthing yourself before touching a fuel line is a sensible thing to do.

L6.

[Pinkman]

GB is right - its almost always static, but the path is actually to the car body filler hole not the nozzle, which is isolated (or maybe the car to you). You have to try REALLY hard because the vapour is usually above the Upper Explosive Limit. As the fuel goes in, it displaces neat vapour out (we still do not have Stage II vapour recovery at more than a few retail sites the UK).

Rainboe, theoretically yes. See http://amd.nbc.gov/library/dm/fuel_hb.pdf

There are specialist conducting plastic cans and funnels for AVGAS I am told but I dont know how available they are.

The problem is due to get worse because Sulphur levels in fuel are dropping and the industry has had some really bad loading rack fires due to low conductivity Mogas (Sulphur acts as an internal static dissipator - not sure of the mechanism).

Don't get caught out by the desert is dry - Europe is wet thing. One of the worst incidents above was in Sweden in below freezing temperatures where the air was so dry but very conducive to spark transmission. And I have had first hand experience in Johannesburg of static ignitions when I was working there.

Again you'd have to be very unlucky. But you know what Clint Eastwood said.....

Pinkman

[prettygrumman]

I think you are all on the right track with static etc. but there could also be another reason.Any transmitting device be it a cellphone or transciever not only transmits a
modulated carrier but also third seventh and mutiples thereof of harmonics. However miniscule these harmonics are, they potentially can interfere with the electronics of the
fuel delivery circuitry, and thus cause errors in fuel readings and/or pricing. Maybe I should try it at Elstree I might get full tanks for a lesser reading!!!:=

[cwatters]

My understanding is that a problem was first identified at petrol stations when CB radio became popular. It was nothing to do with fires, the CB messed with the fuel metering in the pump leading to people being over or under charged. I believe the petrol companies started the fire risk story to stop people deliberately trying to mess up the pump while they were upgraded ti improve immunity. The ban on CB remained "just in case" and was later extended to phones.

If there is a risk to aircraft I supect it's more likely to be due to the potential for interference with the fuel metering but I don't know how that's done on a bowser.

[Sallyann1234]

Any transmitting device be it a cellphone or transciever not only transmits a
modulated carrier but also third seventh and mutiples thereof of harmonics. However miniscule these harmonics are, they potentially can interfere with the electronics of the
fuel delivery circuitry, and thus cause errors in fuel readings and/or pricing.

If interference did occur to the fuel metering (which is very unlikely but theoretically possible) it would be due to the fundamental transmission frequency rather than the harmonics, because (a) the harmonics will be several orders of magnitude smaller and (b) the metering electronics will be less sensitive to the higher frequencies.

[E & I]

Mobile phones are not banned during fuelling. They are banned in the "fuelling Zone" 6 metres radially from the refuel equipment and fuel vents. CAP 748 states they may cause a distraction and if they have an unserviceable battery there is a possibility that they may cause a spark. The CAP 748 does go on to say that there is a possibility that mobile phones may cause interference to the refuel equipment.

A few years ago a technician had a fire bottle squib on his bench when his mobile phone resyncronised itself the squib detonated on his bench.

The IATA fuel manual also provides interesting background reading.