How to safely transfer 100LL without blowing myself up

[JonJay]

I mentioned earlier the FAA has an AC and the NFPA has an entire section on refueling aircraft. It’s a lot of reading and covers much more than transferring fuel, so it would take an effort to sort out what is relevant.

 

[bobnoffs]

i have a 55 gal dot approved tank on a small trailer. when i fuel the plane the stg tank is grounded and the plane is bonded to the stg tank. the filler nozzle is bonded to the tank.
my question comes up about defueling the plane to the stg tank. i use 5/16'' id rubber hose. fuel moves from plane in 15' of rubber hose. thru an automotive fuel pump thru more rubber hose and into the stg tank. after reading this thread i am more uncertain about how to than before. do i run a fine copper wire inside the rubber hose? open to any suggestions.

 

[PaulvS]

After reading this thread and some of the reference material, I would use anti-static hose for any fueling or de-fueling operation, along with bonding between the fueling equipment and the aircraft and the operator. I'm not an expert, but I did pass physics!

 

[MacCool]

i have a 55 gal dot approved tank on a small trailer. when i fuel the plane the stg tank is grounded and the plane is bonded to the stg tank. the filler nozzle is bonded to the tank.
my question comes up about defueling the plane to the stg tank. i use 5/16'' id rubber hose. fuel moves from plane in 15' of rubber hose. thru an automotive fuel pump thru more rubber hose and into the stg tank. after reading this thread i am more uncertain about how to than before. do i run a fine copper wire inside the rubber hose? open to any suggestions.

Running a wire from some bare metal on your airplane to the recipient tank will accomplish the same thing. IOW, your aircraft needs to be "bonded" to the storage tank. Doing that through a conductive hose is one way to do it. Note that that hose conductivity isn't necessarily an actual wire....these days it's more likely that the compounding of the hose material or the hose liner is conductive. As mentioned...the very low current passed in a static discharge means that the "bonding" path doesn't need to be particularly robust. Note that the fuel tubing that you buy off the reel at your hardware store isn't likely to be conductive.

 

[MacCool]

Some FBO's will fuel inside the hangar with the door open and the airplane in the front of the hangar.

At my airport, all aircraft fueling is done from a truck. They're happy to fuel in the hangar if the door is open. I generally push it out a bit to make it easier for them so that they don't need to unreel as much hose (the truck does need to be a certain minimum distance from the airplane).

 

[Sam Buchanan]

At my airport, all aircraft fueling is done from a truck. They're happy to fuel in the hangar if the door is open.

I wonder what the insurance carriers think about this.....................

 

[JonJay]

The FAA has an AC, which is only a recommendation, not a law, that refers to the NFPA articles on aircraft fueling.
It specifically states that aircraft are not to be fueled in hangars and fuel trucks are to be minimum 50’ from hangars or buildings while fueling.

However, it isn’t illegal to do so unless your airport or the jurisdiction covering your airport have adopted the NFPA in regard to this. It still may not be “illegal”, but it may be a violation of the jurisdictions statute, or a “violation”. No a legal beagle so the difference might just be wording…..

The way I read this; the FAA doesn’t have an enforcement right and the NFPA is just a rule making body and has no enforcement arm.
So, is it the State, County, or ??? Who has jurisdiction at your airport and have they adopted the AC or NFPA “rules”.

I would believe the local Fire Marshal, if anybody, would have enforcement responsibilities including violations and fines.

This is just my guess after reading the FAA AC and the appropriate NFPA chapter.

An insurance company doesn’t have a leg to stand on unless they can show a statute was violated.

 

[Sam Buchanan]

An insurance company doesn’t have a leg to stand on unless they can show a statute was violated.

Unless there is a provision in their policy that refuses coverage for a fire that occurred while an aircraft was fueled in a hangar.

I don't know if airport insurance policies typically have such a provision........just wondering.

 

[JonJay]

Unless there is a provision in their policy that refuses coverage for a fire that occurred while an aircraft was fueled in a hangar.

I don't know if airport insurance policies typically have such a provision........just wondering.

Our private airport did not. My current ground lease does not. My current insurance does not.
However, the State Owned Airport my ground lease is on may have statutes, or insurance clauses, that have not be shared with me.

 

[MacCool]

I wonder what the insurance carriers think about this.....................

No clue. I don't know what the FBO's actual policy is, as opposed to what the line guys actually do. Personally, I would have no objection to pulling it out of the hangar.

 

[Sam Buchanan]

No clue. I don't know what the FBO's actual policy is, as opposed to what the line guys actually do. Personally, I would have no objection to pulling it out of the hangar.

I asked my local airport manager about this a few years ago when I observed his line folks fueling aircraft in hangars. He agreed the airport insurance carrier most likely wouldn’t like that practice.

However, he was in an awkward predicament because some owners don’t want a line flunkie moving their plane. And those owners show up on short notice expecting topped tanks. So………..

Yes, the answer is for aircraft owners to accommodate airport personnel and not put the airport in a potentially tight spot. Arrive early enough to pull the aircraft out of the hangar for fueling……..but that is too reasonable…….

 

[RV8JD]

I would believe the local Fire Marshal, if anybody, would have enforcement responsibilities including violations and fines.

I have a Condo hangar at a municipal airport. Attached are the fire regulations from the city's fire department. Note the first requirement on the second page: "Flammable liquids shall not be dispensed into or removed from the fuel system of an aircraft within a hangar".

 

[Sam Buchanan]

This from the ******** ******** Regional Airport Rules and Regulations where my RV-6 is based to which all tenants must agree:

Section 6, paragraph 1;

"No Aircraft shall be fueled or drained while the engine is running or while the aircraft is in a hangar or an enclosed area."

 

[Bill Boyd]

Grounding to the earth could have a significant impact if the fueler approaches an open fuel tank while being grounded to earth but not the plane. When I was in a military flying club we were required to ground the truck to the earth, the plane to the earth, and the plane to the truck or pump when refueling. Those were our instructions and we followed them. I suspect that this procedure eliminates almost all risk. We also stopped fueling when lightning approached to a specified distance I believe, but my memory escapes me on the distance. Fuel vapors are dangerous critters. The danger is NOT overrated. I have not seen a plane fire from refueling but I did see a yacht flash fire due to improper fueling procedures. It WILL make a believer out of you when you see how far and fast that fuel vapor fire flame front propagates and the energy released. On the occasion of the yacht fire, I saw a person who could not swim jump overboard with the assistance of the shock wave (he was rescued). It was something I will never forget.

Yup. I saw a motor yacht explode in the Lafayette River behind my house in 1975 our so. The image of that fireball was seared in my mind for months afterward. Everyone survived because they were blown clear and were able to tread water until I and several neighbors swooped in to pluck them from the water in our ski boats. They had a fuel leak in the motor box and someone flipped on the bilge blower... The boat, which burned to the waterline in minutes, was named "Boomer." Irony.

Back to the subject at hand -I have always assumed that when approaching the plane whilst holding a petrol pump dispensing handle situated at the end of a conductive fuel hose, my body is as grounded as anything else in the loop at that point. I would also assert it is physically impossible to unlock an RV fuel cap holding the metal key in your hand without dissipating any potential difference between yourself and the airframe. My opinion is not really important here, but here it is: we are mostly overthinking this.

There are a LOT of things I stop doing when lightning is nearby. Fueling an aircraft would certainly be one of them, but unrelated to the risk of an induction spark between pieces of fueling apparatus and more related to keeping myself medium-rare or cooler.

Those of you who have to abide by lease terms are of course well-advised to do so, whether they reflect prudence, paranoia or some combination of the two.

 

[MacCool]

I don't see any fuel trucks at the FBO's adding another ground connection to a hangar, tie down ring or anything else. The only grounding wire goes from the fuel truck to the airplane.

Heh...as I was getting my plane fueled the other day (I did push it out of hangar for the line guy), I noted that once connected, the bonding cable naturally lays on the ground thus actually grounding both the pump and airplane as well as bonding them to each other. I hadn't thought of that. Not sure if that's by design, but it's the ultimate effect.

 

[Sam Buchanan]

Heh...as I was getting my plane fueled the other day (I did push it out of hangar for the line guy), I noted that once connected, the bonding cable naturally lays on the ground thus actually grounding both the pump and airplane as well as bonding them to each other. I hadn't thought of that. Not sure if that's by design, but it's the ultimate effect.

The "grounding cable" on the self-serve pump at my airport is insulated........wouldn't be surprised if that is to prevent personal injury from a broken strand penetrating skin while handling the cable. But since the pump is grounded it wouldn't make any difference if the cable is insulated.

Just another datapoint.

 

[gasman]

Note that most of this discussion is focused on ensuring that voltage potential between the fill nozzle and the plane are minimized but there is another potential spark and fire risk that is seen occasionally during automobile refueling with automatic gas station nozzles. This occurs when the person fueling steps away from the pump while it's fueling, then creates a spark when they touch the nozzle again to remove it from the tank. This video is frequently shown in ESD awareness training videos:

This is something to be aware of, particularly if you are draining a tank into a fuel container, step away, then come back and touch the container! If the container is "bonded" to the aircraft, be sure to touch the aircraft in an area away from the fuel vapors before touching the fuel container!

Skylor

In this video, the girl went back into the car and sat down and then slid out without touching the door, that would have discharged the static charge she created between her pant material and the material of the seat. Polyester clothes and the right level of humidity will do it.

This is less likely to happen in California due to the vapor recovery system designed into the dispenser nozzle.

 

[Dugaru]

In this video, the girl went back into the car and sat down and then slid out without touching the door, that would have discharged the static charge she created between her pant material and the material of the seat. Polyester clothes and the right level of humidity will do it.

I've read that people of a certain age are less likely to start these fires (which almost always involve re-entering the vehicle), because as people get older they tend to grab the frame/door of the vehicle for balance and leverage when entering & exiting. So there's ONE advantage of being old I guess.

 

[skylor]

This is less likely to happen in California due to the vapor recovery system designed into the dispenser nozzle.

Yes, but the context of this discussion is de-fueling airplanes, not filling a car in California. I actually know of a fire that ignited from fuel residue on a plane that was being prepped for wing removal during the 2022 races at Reno, semi-outdoors, and was ignited by static electricity.


Skylor