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Grounding your home base fuel tank

I still don't get why you'd ground a DC system. The requirement to bond is exactly the same with or without. Grounding is an electric code thing. 120vac is grounded. Nothing I know that's 12 or 24vdc is.
Didn't say to ground the DC source to the tank ground, would have to research that. In my view, AC or DC a tank can build up a static charge just as can just walking up to it on a really dry/cold day can do and I want that charge to go to ground via a path that doesn't include me or what I'm fueling but mostly I'm thinking grounding for lightning protection. I often see diesel fuel tanks like this on our project sites and the majority are grounded.
 
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A bonding ground is a connection to eliminate or at least minimize static charges and stray voltages. Has absolutely nothing to do with any powered equipment, whether AC or DC.

Have you seen old school fuel tanks that were built uphill in order to use head pressure to get the fuel to flow? They don't even need fuel pumps installed and they are connected to ground rods. Static charges in fluids can build up simply from the motion of the fluid over a surface. So when fuel is moved into or out of a tank it can generate a static charge big enough to cause a spark (in a dry environment, the wind blowing sand over a surface will build a static charge). If the tank does not have continuity to the ground and/or structure around it, the static charge continues to grow until the spark jumps. If that same tank has a connection to a ground rod, static charges will flow through the connection to the dirt around the tank. This 'bleeds off' the static before it can grow large enough to cause a spark. If you need to refuel from a tank, truck, or even a barrel, connecting the bonding wire from the unit to the aircraft will allow a static charge on the tank OR the aircraft to flow to the other unit, making them equal in voltage. This eliminates the chance of a static spark when touching the nozzle to the filler neck.

Someone else tag me out, here.

Web
 
The only thing I could add to Web's summary is the importance of getting a good power company neutral to the tank. Then you get the benefit of all the grounds rods in the area. Important in sandy soils.
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?


You should be concerned for good reason...To be safe, you need to bond the fuel in the can and the plane to a ground. I have been fueling some with plastic race jugs but only when it’s humid. I use a metallic 90 on the spouts that I contact to the aircraft tank when fueling which makes me feel better but I have also ordered a large diameter ring-connector that I can put on the 90 and attach a bonding conductor too and plan to attach it to the lifting rings and then bond the aircraft frame to a grounding point.

Still trying to figure out how to test my contraption, without trial and error.
 
Another question- is a floatplane in the water grounded, and thereby bonded to the fueling system(assuming its grounded)? I’ve been around a lot of 135 and other floatplane ops here and have never once seen one grounded/bonded during fueling. For that matter, I’ve never seen them do it on their wheel planes either, except at the airport... Not saying it’s a good idea, just what I’ve observed.
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?

Do a search on this site. There is at least one VERY long thread on that very subject.

MTV
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?

Be cautious with plastic, funnels or jugs. The good ones are conductive. The bad ones aren't.

Web
 
Another question- is a floatplane in the water grounded, and thereby bonded to the fueling system(assuming its grounded)? I’ve been around a lot of 135 and other floatplane ops here and have never once seen one grounded/bonded during fueling. For that matter, I’ve never seen them do it on their wheel planes either, except at the airport... Not saying it’s a good idea, just what I’ve observed.

No. Freshwater is not very conductive. Saltwater is phenomenally conductive but don't land your airplane in saltwater, lol.
 
I used to deliver methanol in Prudhoe Bay, Alaska. Being the north slope, static electricity is a huge deal. I have had static jump through my leather gloves from doorknobs.

Anyway, the methanol would flow from my 10,000 gallon tanker to the storage tank filling from the bottom up. This prevented a static charge from being created by free falling fuel from the top down.

Soo, now that I will be grounding and bonding my fuel supply system, I will add one more precaution which may be Overkill. When I insert the nozzle into the wing tank, I will minimize fuel free fall by getting it in there as far as it will go. At some point the fuel will begin to cover the filler tube of the nozzle and there will be no more free fall which may cause static.
 
All it takes is once of course. But after 55 yrs of transferring fuel in Alaska year round all seasons into anything that uses it - I've never had a spark that created a fire. I do keep a fire extinguisher handy. The one fire I was made aware of involved a Lower 48 Cub draining a main tank into a container on the ground from an open quick drain during summer. The owner moved the plane but the fire was faster. Every year thousands of town and bush people fuel their vehicles from ungrounded plastic and gasoline tanks. Safe? No. Works? Sometimes.

Gary
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?
I think there is some confusion in the use of the words "ground", "grounded" and "bonded". They are similar in practice and meaning. They are often used interchangeably without much thought. The whole idea is to use an unpowered metallic connection (ground wire or bonding wire) between the originating container of the gasoline and the place where you are putting the gasoline. This will ensure there is no electrical differential between the two locations. With no electrical differential there will be no spark.

Plastic jugs have the ability to make their own static charge.
 
Ive had one fueling with a chamois The winter of 69 in hughes alaska. metal cans. when i tipped the can into the funnel it aught fire,. I threw the almost fuel an off the back side of the wing. It was -35. You guys need to pay attention to wire weinie and read the proper procedures. Pa -12 burned up in cys hangar in manle
All it takes is once of course. But after 55 yrs of transferring fuel in Alaska year round all seasons into anything that use for not proper boning. There have been at least 4 hangers in alaska that have burned to improper bonding.
- I've never had a spark that created a fire. I do keep a fire extinguisher handy. The one fire I was made aware of involved a Lower 48 Cub draining a main s need to ptank into a container on the ground from an open quick drain during summer. The owner moved the plane but the fire was faster. Every year thousands need to under stand wire ws of town and bush people fuel their vehicles from ungrounded plastic and gasoline tanks. Safe? No. Works? Sometimes.

Gary
 
Naive question here - what about fueling from plastic fuel jugs? I've started running a mixture of 100LL and 87 mogas, and I use normal 5 gallon fuel jugs for the mogas. I feel OK doing so in the summer, but the idea of doing that in the winter has me concerned about static. Would it do any good to drive a ground rod into the soil outside my hangar and connect that to my airplane when fueling from a plastic jug?

If you use plastic jugs on the wing the safest way I know is to use racing jugs (AIH) and keep the long pour hose so you can immerse the hose end into the fuel in your tank. Use a rag around the hose to guide the hose into the filler and keep it there to close off the filler area from air transfer. The air in the tank is usually too rich to ignite. Keep fumes inside the tank. The smooth hose dumping directly into the fuel in the tank minimizes static generation and race jugs empty quickly so exposure time is reduced. I've done the funnel thing, too. Race jugs work better for me.
 
Ask Charly Center about fires and hangars. Sadly lost his new setup in Wasilla years ago to a fire...not sure but I think he said there was defueling or wing work going on. Plane was behind others that slowed the exit.

Gary
 
“Ground” is relative. Contrasts: From a micro watch battery terminal to a nuclear generator earth ground.

We all live with several different “Grounds” on a daily basis. Cars, iPADS, DC & AC. etc all have different and distinct “Grounds”.

“Grounding” everything together is not the solution. Understanding electrical potential is the key.
 
Electrical grounding and static bonding are two different things that look nearly identical.

First, a grounding conductor is incorporated into an AC electrical circuit to prevent you from being intimately involved in that circuit if a line wire comes into contact with a metal part that you might touch. This can ruin your day.

Second, bonding items together and to the GROUND is to help eliminate a build-up of a potential between two electrically isolated things and a resulting spark jumping across them to equalize that difference. Your vehicle picks up a charge from moving through the air; sometimes it is a lot, other times it is not noticable. This charge might be (and usually is) different from the charge of the tank you want to use. When you attach your bonding wire from the reel, you are equalizing those charges and the spark happens right there at the connection, if at all.

Bonding using the nozzle of a gasoline hose where it meets your fuel tank filler neck could also ruin your day.
 
My habit is to tap the plane's lifting ring first with the hose nozzle before opening the cap. For a few years I wore insulated nylon overalls in winter but quit when I threw a spark touching metal with my finger.

Gary
 
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