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Grounding Drums


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Does anybody have a good method of actually accomplishing the proper drum grounding procedure?

 

 

Drums should be placed near grounding posts to allow for this connection

and the sequence should be:

(a) drum to ground;

(B) ground to aircraft;

© drum to aircraft; and

(d) nozzle to aircraft, before tank cover is opened.

 

When disconnecting reverse the order d., c., b., a.

 

It might be easy to do if you have a semi-permanent installation. How about remote fuel caches? It would be nice to avoid this:

 

http://www.sandylake.firstnation.ca/press-release-wasaya-airplane-fire

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If the drum and the a/c are sitting side by side on the same piece of earth are they not both grounded?

 

But what about the rubber fittings between the landing gear and the clamps, don't those insulate the rest of the a/c from the ground? Darn!

 

How about if I use a piece of cable to connect the drum, which is sitting on the ground with the standpipe screwed in and the pump clamped on (therefore all bonded) to the grounding point on the a/c? Just gotta be sure to use the teeth on the clamp at the end of the cable to scratch some of the paint off the barrel so that the clamp makes good contact with said barrel. Still not as good as a grounding post, but good enough?

 

And one mustn't forget when refueling an A* that only the first few cm of the fuel spout is grounded, cuz the further down the spout is either the plastic tank or the rubber piece connecting the tank to the mouth of the spout. Good time to have a bonded hose so that the end of the hose isn't sitting in the spout generating a nice little static charge!

 

DM

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Grounding a drum,,,,,ahhh what about sitting upon 4 feet of snow on top of frozen solid. dirt. Fuel trucks are not grounded(on rubber tires), airplanes are not grounded(on rubber tires), nothing needs to be grounded..........BONDED is the word. To properly ground something you need to drive a ten foot steel rod into ground, look at your house. This is not a new word. Bonding is not optional, is mandatory between everything that flies. Can you dump fuel out of a plastic can into your helicopter, you bet as long as there is a bonding cable from inside the can(and in fuel) to aircraft. Grounding,,,,,I had a company go into this with me years ago, I asked what the **** they expected to happen in winter,,,got stupid look, suggested I buy a sledge hammer and spike,,,,fml

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If the outifit you're working for is half desent, there should be a portable grounding post complete with cable with your refuel kit that you can shove into the ground near the drum.

Regarding the landing gear rubber mounts. There should be bonding leads which link one component to another around the mount, providing continuity.

In my younger days, I was rather fastidious regarding grounding procedures. As time went on, especially if I was in a rush or under a bit of pressure, I became lazy and somewhat blaze' regarding it. But not so long ago, I was hanging out by the machine with a couple of engineers who were shooting the sh*t about this and that. The subject turned to grounding and the horror stories stared, what they had seen first hand. Needless to say, I once again make sure everything is as it should be before I put the fuel nozzle anywhere near the aircraft. Even then, I ground the nozzle on the landing gear first before putting it near the tank filler.

 

Just another thought regarding fuel trucks. The RAF bowsers always had a stiff braidded rubber strip that rubbed on the ground. Can't recall seeing them on commercial fuel trucks. Interesting...

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Grounding a drum,,,,,ahhh what about sitting upon 4 feet of snow on top of frozen solid. dirt. Fuel trucks are not grounded(on rubber tires), airplanes are not grounded(on rubber tires), nothing needs to be grounded..........BONDED is the word. To properly ground something you need to drive a ten foot steel rod into ground, look at your house. This is not a new word. Bonding is not optional, is mandatory between everything that flies. Can you dump fuel out of a plastic can into your helicopter, you bet as long as there is a bonding cable from inside the can(and in fuel) to aircraft. Grounding,,,,,I had a company go into this with me years ago, I asked what the **** they expected to happen in winter,,,got stupid look, suggested I buy a sledge hammer and spike,,,,fml

 

skullcap is right, grounding aircraft was given up a good while back. Bonding is what needs to be done allowing the electrical charges to equalize between the aircraft and the fuel source. If both have the same charge, one charge doesn't want to jump over and equalize on its own, thus going boom.

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Oh by the way Dimit, there is a bonding cable on astar gear to ariframe. And you do NOT want the fuel to be equalizing the potential in fuel(that is bonding wire's job) so the fact the tank of astar is plastic is no different than any other helicopter where are usually rubber. Bond the drum by screwing in the standpipe, install inpump, ensure there is bonding from this to helicopter(tie wrap cable to hose) and to nozzle then aircraft. Have had three pumps fail where as they shorted internally and the case of pump became the live. Electrical energy went down bonding wire to aircraft and started to smoke.....no fire,,,just turned off pump, installed spare carried on.

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Thanks Skullcap,

 

I'd suspected the landing gear had to be bonded to airframe, but never seen the piece 'o wire.

 

I think we're saying the same thing about the hose nozzle. My point about the A* spout is primarily in comparison w/ 206 where the hose nozzle usually bonds to the airframe through the range extender. On an A* if you're not using bonded hose the nozzle has to be in contact with the airframe in those first few inches of the spout, otherwise the nozzle can build a static charge which could lead to arcing and other unpleasant consequences.

 

Your examples of the pump internal shorts should be enough to convince everyone of the wisdom of using a bonding wire.

 

Cheers,

 

DM

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