“”Your article on grounding the airplane prior to fueling was informative on why we ground the plane,”” wrote Ken Kellogg after he read my June 9 column, “”Grounded: What’s the proper way to ground during refueling?””
“”Your article on grounding the airplane prior to fueling was informative on why we ground the plane,”” wrote Ken Kellogg after he read my June 9 column, “”Grounded: What’s the proper way to ground during refueling?””
“”Unfortunately,”” Kellogg continued, “”it failed miserably when it did not give one example of where on the airplane the grounding cable should be attached. Where is the grounding lug? My owner’s manual fails to show it.””
I went back and reread my column and he is correct. I told people that they should use a volt-ohm meter to check to ensure that there is continuity from their grounding point to the fuel filler neck. But where is the correct, specified grounding point for an aircraft?
I have always used the exhaust stack or the engine, but is that the recommended point? I checked a few manuals and found no answer. I then called Cessna, where an official checked its manuals for GA aircraft and agreed that there is no grounding point specified. I then asked, “”where do you connect the ground wire when refueling?”” The answer was that they used the tie-down point under the wing or the exhaust stack.
So I guess there is no definitive, specified grounding point for most GA aircraft.
But I will go back to my original point: what is most important is that each pilot should check that there is continuity between the grounding point selected and the fuel filler neck.
On this same subject, I received an interesting note from Doug Millard of Alaska. He sent me a copy of the latest National Fire Protection Association (NFPA) Standard 407 on “”Aircraft Fuel Servicing.”” In the standard section 5.4.1, it states “”Grounding during aircraft fueling shall not be permitted.”” I called NFPA and asked them for the reasons behind this statement. They said that in tests at the Denver Stapleton Airport, especially when lightning is present, they feel it is safer to not ground the aircraft, but rather to just bond the aircraft to the refueler.
I do not understand everything about this subject, so I am trying to find the reports on this test and will let you all know if I learn anything.
I have also been looking for hard data on how many accidents have been caused by lack of grounding. So far I have not located any conclusive data that I can pass on. I have found that de-fueling an airplane has caused a significant number of accidents. I assume this is because most people are aware of the need for grounding during fueling and that the fueling hose is conductive. But when people de-fuel an aircraft, they do not have a conductive hose and forget about the need for a grounding strap.
Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985. You can contact him at [email protected].
