Grounding for fuel

Stewartb said:
Bonding is the more correct description. Most of us bond the plane to the fuel dispenser with a separate wire but likely the fuel hose is also bonded so some guys count on that.
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Pretty bad technique I think. You could get the spark between nozzle and tank if the plane isn't already grounded.
 
Grounding has nothing to do with anything. Watch the video I just linked. This isn't new science.
 
I maintained and drove fuel trucks here at NAS back in the 80's, when we replaced a fuel hose on a truck we would solder a #10 copper wire to each end of the hose by threading it thru the hose so that each end was bonded to the other. When that hose is connected to the truck and the nozzle it will bond the truck to the aircraft in the event the the crew does not. I believe this is a standard practice, but you know how that goes.

When you exit the aircraft, do you know absolutely that the aircraft holds no static charge? (it is mounted on rubber tires) when you open the fuel cap doesn't the fuel fumes start to exit the tank thru the open filler? wouldn't that be an ideal time to fine out that the aircraft is discharging the static charge thru the hose?
 
Easily mitigated by tapping the airframe with the nozzle prior to sticking into the filler. Not perfect but effective when done properly. And it's controlled by me, unlike the attachment of a bonding line that's provided. i can't verify whether the bonding line is attached correctly or that it has continuity. Should I have absolute trust in that? No matter, my typical fuel ops utilize my own equipment. I've been filling my truck tank and my airplane tanks for 20 years without incident and honestly? I get more careful as I get older. I used to drag plastic jugs across the frozen lake on a plastic ahkio sled while wearing nylon and gore-tex. I'd climb onto the plane and pour those jugs using the bellows nozzles that came with the jugs. I did everything wrong and I never had a fire. No matter, I'll never be that careless again.
 
EdFred said:
Maybe he'd been trying to sell his plane and couldn't get a buyer....
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Duh, then you get Henning to fly it to Osh........hello!


Edit: Just joking, Henning, but that was served on golden platter.
 
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Stewartb said:
So..... you pull up to a self-serve avgas place and the bonding cable clamp has fallen off or been cut off. Do you add fuel or go on your way without? That isn't just a hypothetical question. My local self-serve place had that condition more than once this year. What would you do?
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Touch the nozzle to the airframe before uncapping and maintain that bond as you uncap and it should be fine.

The trick is to just make sure everything is at the same potential. The nozzle, you, the fill hole, etc....

Edit in: I'd probably take my Kershaw and strip the bonding wire enough to tie it around the exhaust pipe.
 
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The trick is to just make sure everything is at the same potential. The nozzle, you, the fill hole, etc....
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Which you can not do if you don't have continuous electrical contact. Again, the falling fuel will generate static.

I always find it amusing when the fuelers connect the ground line to the nose wheel alignment tab in the Navion. It's a non-conductive piece of bakelite.
 
flyingron said:
Which you can not do if you don't have continuous electrical contact. Again, the falling fuel will generate static.

I always find it amusing when the fuelers connect the ground line to the nose wheel alignment tab in the Navion. It's a non-conductive piece of bakelite.
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Never heard the falling fuel argument until this thread.

Wouldn't the fuel be at the same potential as it leaves the nozzle? It's passing through a metal bonded conductor.

I don't know how conductive avgas is ... I know pure water (notice I said pure) is NOT conductive.
 
txflyer said:
Wouldn't the fuel be at the same potential as it leaves the nozzle? It's passing through a metal bonded conductor.
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Fuel hoses are typically conductive, but once it leaves the hose it's falling through the air and building up a static charge.
I don't know how conductive avgas is ... I know pure water (notice I said pure) is NOT conductive.
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Not very.
 
flyingron said:
I always find it amusing when the fuelers connect the ground line to the nose wheel alignment tab in the Navion. It's a non-conductive piece of bakelite.
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I had a line person at Daytona clamp onto the painted metal scissors of my nose gear.

Even if it gouged it's way down to bare metal (I don't think it quite did), the nose gear is bolted to composite structure, with no attempt to ground it.

The proper place in a Sky Arrow or Cirrus is the exhaust. But again, every pilot should read the section on "Servicing" and not just guess.
 
Would be nice to pull up to a self-serve pump where I didn't have to jam the cable under my nose wheel to keep the rewinder from yanking the clip off of wherever I put it and rewinding it's self.
 
Stewartb said:
Grounding has nothing to do with anything. Watch the video I just linked. This isn't new science.
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Got it. I'm bonding the plane to the pump when I make the hookup. I'm relying that the nozzle is bonded to the pump and the pump is properly grounded (which I guess just means it's bonded to the earth). I don't think the next time the self serve pump asks if the airplane is grounded I'm going to go explain to the FBO that they have this grounding thing wrong though. LOL. Thanks for posting the link.
 
Stewartb said:
So..... you pull up to a self-serve avgas place and the bonding cable clamp has fallen off or been cut off. Do you add fuel or go on your way without? That isn't just a hypothetical question. My local self-serve place had that condition more than once this year. What would you do?
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If you're saying the wire is still there, and the clip is gone, I can think of a number of ways to get that "attached" to the airframe.

My favorites ever saw was some place had soldered on a spring clip, and left the little rubber protectors on the tips of the clip. LOL. They found their way to the nearest trash can. Idiots.
 
luvflyin said:
Got it. I'm bonding the plane to the pump when I make the hookup. I'm relying that the nozzle is bonded to the pump and the pump is properly grounded (which I guess just means it's bonded to the earth). I don't think the next time the self serve pump asks if the airplane is grounded I'm going to go explain to the FBO that they have this grounding thing wrong though. LOL. Thanks for posting the link.
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I notice that when being fueled by a truck that the truck and the airplane are bonded but the truck is not grounded to earth. The cable runs along the pavement but it is my understanding that asphalt is an insulator so that wouldn't have much grounding effect.
 
Grounding isn't convenient or important for most mobile fuel trucks. Including my own. Equalizing the static potential between the dispenser and receiver is what's important. It doesn't matter that static is present, there won't be a spark unless one has more static than the other. Bonding fixes that. It sounds like the majority of you get gas at fuel facilities. Most of those will have protections built in. Mobile fuel staff are trained to use a bonding wire. The bigger risk is fueling when out in the boonies with plastic jerry jugs. That risk is less understood and more difficult to manage. I use a Mr Funnel but lots of guys up here still use a metal tractor funnel and a chamois.
 
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