round_peg Posted December 19, 2011 Report Share Posted December 19, 2011 We were refueling our CTsw on the taxiway today after a flight, from our jerry jugs as usual, when someone happened by and suggested that this might not be a safe procedure. His concern was that on dry days enough static electricity could build up on the composite airframe to throw a spark. This seemed like a far-fetched possibility but it seemed worth running past the gathered. You can't ground a composite airframe so I don't know how the problem would be solved, if indeed it is one. Thoughts? Link to comment Share on other sites More sharing options...
chanik Posted December 19, 2011 Report Share Posted December 19, 2011 You can ground through carbon fiber actually. But the reason you don't need to worry about it is you end up grounding yourself anyway when you touch the caps to take them off. Link to comment Share on other sites More sharing options...
round_peg Posted December 19, 2011 Author Report Share Posted December 19, 2011 You can ground through carbon fiber actually. But the reason you don't need to worry about it is you end up grounding yourself anyway when you touch the caps to take them off. Not sure what you mean by "grounding yourself." If I understood what this person was telling me, it is static electricity building up on the surface of the composite that is the concern. Are you saying that simply touching any part of the airframe discharges it? Link to comment Share on other sites More sharing options...
chanik Posted December 19, 2011 Report Share Posted December 19, 2011 Yes. Because whatever charge stored on the plane will conduct to the cap and would zero out with your human body charge potential when you touch the metal cap with a possible spark that, BTW, I've never once felt. Link to comment Share on other sites More sharing options...
josjonkers Posted December 19, 2011 Report Share Posted December 19, 2011 Oh the `helpful`pieces of advice others try to impose on you..... I have been fueling my CT this way for the last 6 years, and other than making sure you don`t overflow the tanks (which I have done once or twice) I `have not seen any static electricity issues , and I live in a fairly low humidity climate. Link to comment Share on other sites More sharing options...
Roger Lee Posted December 19, 2011 Report Share Posted December 19, 2011 Many of us fuel from plastic cans. The carbon fiber will conduct a charge and it can be grounded. Just like the others have stated. You touching the frame and keeping contact all the while holding the jug will keep the static away. I would say the that us CT folks in Arizona have a dryer climate than most. Single digits at times. No one at my field has ever had an issue. If you don't believe this take the positive lead under your planes cowl that sticks out for jumping or charging. Pull it around and hold it against the grounded carbon fiber and watch it glow and burn. You could even ground a plastic can with a wire. Actually don't really do it as I already know the results. It will glow and burn because the carbon fiber is grounded to the metal frame and battery. Since you brought this fire issue this is a good time to remind many that keeping the fire extinguisher in an easy to get to spot ( not behind the seat in a tightly covered pouch) is a good thing to have around. Link to comment Share on other sites More sharing options...
round_peg Posted December 19, 2011 Author Report Share Posted December 19, 2011 I figured most of us were fueling from jerry cans, unless we've got taxi access to an unleaded gas pump -- which I'm guessing is approximately nobody. We fuel with a wooden platform contraption that my inventive co-owner partner made. The cans have a spout with a valve that screws into the top. The platform sits on the wing and the cans lay on their side on the platform. So you can walk around and do other things while they drain. I take it from what folks are saying here that touching just about anywhere on the airplane should discharge any static electricity that may have built up while flying? What about an alligator clip on the exhaust, attached to a piece of bare wire to lay on the ground? The person who suggested this might be a problem wasn't trying to come off as any authority on the matter. I think he was simply suggesting that we look into it, based on what he'd heard from others. Coastal So Cal can be radically dry too, often in the single digits RH in the fall and winter. We can snap, crackle and pop with the best of 'em. Link to comment Share on other sites More sharing options...
CT4ME Posted December 19, 2011 Report Share Posted December 19, 2011 Technically they are right, but practically it doesn't happen. 'Haven't heard or read of any instances of fueling issues. Cars are subject to the same issues, but with the millions fueling every day, you don't often hear of problems... and cars are worse because you often have passengers getting in/out, cause potential static. Our airport requires a permit to be able to self-fuel your aircraft. You watch a movie and take a test. In the movie, they cover the static issues, grounding, ventilation, etc. Also, I think they require you fuel 50 feet from the hangar. Tim Link to comment Share on other sites More sharing options...
wlfpckrs Posted December 19, 2011 Report Share Posted December 19, 2011 We love our battery-powered, 30-gal gas caddy, which pumps the gas up to the wings. Link to comment Share on other sites More sharing options...
Roger Lee Posted December 19, 2011 Report Share Posted December 19, 2011 Actually I have a 30 gal. HazMat rated barrel with a 12V UL rated pump on a little flat dolly for gasoline. I just dump my fuel in their. It has a regular fuel island nozzle and hose. Link to comment Share on other sites More sharing options...
round_peg Posted December 19, 2011 Author Report Share Posted December 19, 2011 Does using an electric pump do anything to address the static issue? From what I've read, auto gas pumps are grounded through the filler nozzle. I suspect that this is a practical non-issue all around, but if there's any easy measures we can take to reduce the chances of a spark to real zero then I wouldn't want to miss them. Link to comment Share on other sites More sharing options...
Roger Lee Posted December 19, 2011 Report Share Posted December 19, 2011 The fuel nozzle on my handle is bonded with a wire that runs through the hose to the pump, the metal pump is bonded to the metal barrel, the barrel and pump are bonded to the battery, the barrel has a wire that bonds the plane at the exhaust pipe and then you can run a wire and clip to a ground source like your metal hanger. bonded and grounded. Link to comment Share on other sites More sharing options...
round_peg Posted December 19, 2011 Author Report Share Posted December 19, 2011 Is this a commercially available product or something you worked up yourself? If the former, what is it called and how much does the rig cost? Link to comment Share on other sites More sharing options...
Roger Lee Posted December 19, 2011 Report Share Posted December 19, 2011 I was a Captain HazMat Tech on the fire department. I made it myself and is very easy to do. Buy a wheeled cart from Harbor Freight, go to a barrel supply and get a 30 gal. 1A1/X1.8/300 and then Northern Tool on line catalog and buy a UL rated 12V gasoline fuel pump. It must be rated for gasoline. Most are rated for diesel so make sure it says gasoline rated. Then pick up a sealed maint. free 12V deep cycle battery. I charge it about every 2-3 months. Now you have a nice 30 gal. fueling cart with a regular fueling handle with a 10' hose. The barrel is about $50, pump about $249, cart $60, battery $70-$100 Link to comment Share on other sites More sharing options...
DocRon Posted January 20, 2012 Report Share Posted January 20, 2012 As an alternative, I got tired of lifting 5-gallon cans over the wing myself. So, I bought a farmer-type transfer tank/tool box combination for the bed of my pick-up. It holds 75 gallons and feeds through a 13 gpm pump and a 14 foot hose. Total cost: about $700 but makes refueling quick and safe (and nearly $2.00/gallon cheaper). In addition, if needed I can fuel my truck gas tank directly giving me (potentially) 101 gallons total and a 1700 mile driving range. I put one grounding cable to the metal hangar and the exhaust stack and another one between the fuel tank and the exhaust stack. Plus, the fuel hose has a wire running inside it between the tank and the nozzle. So, I feel pretty comfortable with refueling, even in the VERY dry sub-zero temperatures of northern Minnesota. Link to comment Share on other sites More sharing options...
Duski Don Posted January 21, 2012 Report Share Posted January 21, 2012 I figured most of us were fueling from jerry cans, unless we've got taxi access to an unleaded gas pump -- which I'm guessing is approximately nobody. We fuel with a wooden platform contraption that my inventive co-owner partner made. The cans have a spout with a valve that screws into the top. The platform sits on the wing and the cans lay on their side on the platform. So you can walk around and do other things while they drain. I take it from what folks are saying here that touching just about anywhere on the airplane should discharge any static electricity that may have built up while flying? What about an alligator clip on the exhaust, attached to a piece of bare wire to lay on the ground? The person who suggested this might be a problem wasn't trying to come off as any authority on the matter. I think he was simply suggesting that we look into it, based on what he'd heard from others. Coastal So Cal can be radically dry too, often in the single digits RH in the fall and winter. We can snap, crackle and pop with the best of 'em. Link to comment Share on other sites More sharing options...
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