Luck was on my side.

From a tip through a pm I took a second look at the pump on my bulk fuel trailer. It is a GPI gear driven positive displacement pump, not a vane type pump. Switched the leads on the battery, removed the end nozzle and the pump gos backwards.

I grounded the plane to the hangar and the fuel trailer to the plane. Stuck the hose into the fuel tanks and sucked them almost dry. The fuel hose is a little big and clumbsy for getting all the fuel out, but it is static guarded.

Found two old steel 5 gallon oil cans and a metal funnel. Pulled the plug from the bottom of the fuel selector valve and drained about 9 more gallons. This 100LL will make an old farm truck run real good.

Lifted the tail of the plane off the floor about 30" and drained a few cups of fuel out of the belly. An hour later when everything was dry and the fumes cleared the hangar, the bomb was finally gone.

Next time I will try to catch the leak when it is only a drip.

My mechanic had the o-rings on hand and rebuilt the valve yesterday. Depending on how much my phone rings when the sun comes up, I might install it today.

Bill

Nice thing about the Great Plains pumps is also that they will sell you a rebuild kit if your pump quits. I had a 12 GPI pump that moved 60,000 gallons of avgas before the impeller shot craps. A $6 rebuild kit, twenty minutes (I read the instructions, so it took longer) and last I saw of it, it had pumped a total of 80,000 gallons. And, no, I did not misplace a decimal.

Sounds like a good safe solution in any case.

MTV

Very interesting discussion. I like the idea of anti static wipes. Or maybe a jug of fabric softener and a rag to wipe down the can prior to transfer. Moisture will dampen the tendancy to build static, but not totally eliminate it. Here where we are finding moisture is never much of a challenge.

The fuel distributor supplied our FBO with a test kit for sampling fuel from the pump. It amounts in part to a 5 gallon plastic bucket with a copper strip bonded to the inside, and another one bonded to the outside sanwiching the bucket between them and bolted together and to a grounding lead. It would seem they are attempting to address the issue of a charge building up on the outside of the container as well as inside.

This makes me wonder if a metal collar fitted between the container opening and spout then fitted with a bonding lead to bond the jug, plane and flow. This would rout any charge built up on the jug through the collar and to the plane. Just my nickle worth there. It would be an interesting set of tests to run through.

Another point is to ground the plane especially if fueling is going to be right after a flight because passing through the air will build quiet a charge over the surface of the craft.

Marc,
Again, the problem is that a plastic can is NOT conductive, over its surface. So you can install strips, bands, bolts, or whatever, short of a full metal sheath (at which point you may as well buy a metal can) and you still can't guarantee that a static charge won't build on the outside of the jug, and arc over to something metal, like the plane. or to something flesh, like you.

Any time you pour fuel, there is a LOT of vapor around. I'm sure you've all been hearing about the recent incidents involving people lighting themselves on fire in gas stations with cellular phones. Now, think how much energy the average cellular phone zaps out there when it rings......

No pun intended, but the potential is certainly there. Just because it hasn't happened to you yet doesn't mean it can't.

I really wish someone would build a decent aluminum fuel can. That would answer a lot of those issues.

MTV

mtv wrote: I'm sure you've all been hearing about the recent incidents involving people lighting themselves on fire in gas stations with cellular phones. Now, think how much energy the average cellular phone zaps out there when it rings....

This is a joke, right Mike? It's been proven that any auto pump incidents were static discharge from the driver sliding his/her butt across the seat upon getting out of the car, and then discharging at the most inopportune time. Made a pretty good episode of Mythbusters too.

Mike,

The cell phone thing is an urban myth, I would guess it's women who are the highest percentage of victims, and they are the highest users of cell phones, ergo, it must be the3 cell phones. They also are more likely to be wearing synthetic fabrics that lead themselves to generating static electricity on car seats or just by moving the layers together. There is security camera footage showing this exact Scenario, no cell phone in use.

The idea of a collar in the jug is to make a metal sleeve 1.75" in diameter and maybe an inch+ in length. The fuel leaves the jug passes through the metal sleeve then down the filler spout. For the static charge to leap from the jug to the spout end where combustible mixtures are present it must pass through the sleeve. In so doing the sleeve is bonded to the aircraft by the bonding wire and, electricity following the path of least resistance, will wick down the bonding lead to the aircraft canceling the difference in potential, negating the spark. The charge cannot get to the spout to cause the problem at the tank filler. The spout could be either metal or the original plastic that comes with the jug. Or if you pour direct from the can into a funnel, bond the sleeve to the funnel with a second bonding strap and the aircraft again the charge is shunted before it can do any damage.

Zane,

I have no personal experience regarding the concept of cell phones igniting gas fumes. I don't watch television, so I probably missed the program you refer to, if that's what it is. There are sure a lot of signs around gas stations hereabouts, warning one not to use a cell phone and pump gas simultaneously. I assumed those signs were prompted by some fact. BUt that is the extent of my knowledge of that.

Whether that is in fact true or not, it is pretty obvious that most folks do not have a very good understanding of how static propagates, although they seem to understand that nylon or other synthetic materials, when brushed against a car seat can create a static potential. Maybe we should put a metal collar on all the ladies...... Uh, never mind....

But, for example, the "collar concept": The problem with this argument is that the static has to pass TO the conductive collar, right? Plastic cans (for about the fifth time) are non conductive. Therefore, for the possible static charge to reach the conductive collar, it would have to propagate over the surface of the plastic can. In the process of doing so, if you were so unfortunate as to have that happen, it would almost certainly ignite the gasoline vapors surrounding the vicinity of the fill spout.

The point is that it takes very little potential to arc a pretty large spark. Gasoline vaporizes very extensively when poured, surrounding the entire area with very explosive vapors. With very little energy, it is quite possible to ignite this mixture.

The way you prevent these sorts of things is to use cans or containers made from a conductive material. As I noted in one of the first notes on this subject string, a fellow (now deceased) named Monte Parrish in Anchorage, AK was a professional fuel handling specialist. We in the Alaskan Aviation Safety Foundation spent a lot of time with Monte, both picking his brain for safety solutions to fuel transfers, and trying to find some simple fix for this plastic can situation. We never came up with anything short of using metal cans.

MTV

Ok I'll yield with one last observation. It has been my experience in working with electricity, static or otherwise, if it is going to migrate from one potential to another it can't pass across a short to ground unless the voltage potential is so high that it saturates the ground rout and bleeds over to the area beyond. A static charge in dry air will jump about 1" per 1000 volts, usually the amperage is in microamps or milliamps. In the old scuff your rubber shoe soles on a wool carpet, you become a capacitor ready to discharge, when you sneak up on your sister and snap her ear typically you are delivering 200 to 300 volts. if she were to present you with the end of a grounded metal rod she would feel nothing as the charge would dissipate on the conductive material. Your plastic jug will do the same. The metal tube or collar on the mouth of the jug is not bleeding it off a non conductive surface, it is capturing it at the point of jump and shunting it in a closed rather than open circuit to ground thus no spark or ignition source.

One other thing that most people don't know or think of, is that the gas vapor is heavier than air, so it's going to "hide" in every low lying area that it gets to... it's also not going to remain on top of the wing when the fueling is taking place...it's headed down, just like water.... but it takes such a slight breath of breeze to change it's direction...
One of the classes that I was in at a refinery, had a demo, with a colored gas, and when a person walked through it, I was amazed at where the cloud headed!!
When I was unloading gas, I used to get terrified when I'd see someone coming to talk to me and they'd throw their cigarette down on the ground to put it out before they approached the tanker!!
JH

Marc,

I understood what you were getting at. My point was there will be vapors all around that pouring process. The static that moves off the surface of the can would probably go to the collar you describe. The point is, however, that it would very likely be moving through a cloud of gasoline vapors enroute to that collar, so the collar certainly wouldn't guarantee anything. It might help, but......

My friend who ignited himself last year was draining gasoline out of a gascolator. He said at one point, for no reason he can recall, he looked down into the bucket he was draining it into, and there was a glow inside the bucket. He tried to get away from it, but by the time he started to move, the cloud of vapors he was standing in had ignited, and he was on fire. Burned both hands, one pretty badly.

This is ugly stuff, and I certainly wish there were simple and readily available answers.

MTV

Here is part of an email concerning transporting fuel. I know this is probably going to start a firestorm ( pardon the pun ) but something to consider.

Could plastic cans in an aluminum ( aluminium ) float compartment create a static charge on the cans.

TD

I wonder if you guys are aware that carrying fuel in containers in the float compartments is quite dangerous and illegal in the U.S.

See 49 CFR Ch 1 Subpart C 175.310 - Transportation of flammable liquid fuel in small passenger carrying aircraft.

A small aircraft or helicopter operated entirely within the State of Alaska or into a remote area elsewhere in the United States may carry, in other than scheduled passenger operations, not more than 76 liters (20 gallons) of flammable liquidfuel if: ---

(e) Each area or compartment in which the fuel is loaded is suitably ventilated to prevent the accumulation of fuel vapors;

There is no way a float compartment is ventilated or a gas container can be sealed to prevent the escape of fumes on an increase in temperature or altitude. What is worse there is no way to ground a static charge that will develop in a less than full plastic container. One ounce of Gasoline when vaporized and mixed with air has the power of a stick of dynamite.

TD

Just curious, where did you gather the fact of an ounce of gas and a stick of dynamite?

It would take a large volume of air to hold the whole oz of gas in the proper ratio to be explosive.

However, I do understand what you are saying.

Dane

Amen, Brudda.....

MTV

This one is off of google video, Dept of Interior and Mines film.

http://video.google.com/videoplay?docid ... 8801&hl=en

Things that make you go huummm!

Awesome find! Reminds me of being in high school and watching science films.

I was at Harbor Freight today and saw some metal 5 gallon "Jeep" cans, like the military, tall, rectangular style. The were made by Blitz in the U.S.A. They have a plastic lid and spout. For anyone looking for steel gas cans that are compact (versus round).

Wow a fourth page for a thread with minimal hijacking.

Tim

donknee wrote:...saw some metal 5 gallon "Jeep" cans, like the military, tall, rectangular style...They have a plastic lid and spout...

Hi;
Yeah, I saw those too. But...what about the *plastic* spout & filler tube? Wouldn't that eliminate the all important bond 'twixt tank & can? Grrrr.
Especially after seeing the video about static electricty produced by the mines dept, it seems completely nuts that there would be anything built that would obviously sever that bonding necessity.
Berk

Berk,

Yeah, but at least you can bond the can to the plane with a short piece of bonding cable with alligator clips. That would take care of 99.9 % of any static issues.

MTV

I think MTV has a good point. The mere presence of plastic, ie. the plastic top on a Cessna fuel cap, is not necessarily a static generator. The creation of static occurs predominately when you have an insulator (plastic) between two ionic fields where a difference in potential between those fields is created. I don't know how much static could be created pouring through a spout from fuel in a can, grounded to the plane...it seems that being bonded they would be the same potential. If you use a wide mouth metal funnel, you might be able to pour out of the can without the plastic spout...I like to do that when I can, since it is faster. It's just not a perfect world anymore...growing up is over-rated.

Big winds at home. At Boeing field its reported a "loose airplane" in the tiedown area ended upon a couple of other aircraft. (I'm in California working...when I'm not online) Kay tells me a big fir tree landed on the neighbors garage, totalling both vehicles...missed the house. Powers out for a million homes. Up by Eric's at the Hood Canal Bridge...75 mph winds, and 1"-2" of rain....more expected tonight.
Don