lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> When a metal airplane flies, the dust and precipitation in the air impacts the surface of the airplane and knocks off electrons. The airframe becomes electrically charged, compared to terra firma. Upon landing the rubber tires insulate the charged airframe. At the fuel truck, the chargeless line monkey gets within arcing distance with the metal fuel nozzle. Because all things want to be equal, the resident charge on the airframe is CONDUCTED by the metal in the airplane through the metal nozzle and into the conductive line monkey. If the resulting spark has enough energy and the local air fuel mixture is near stochiometric, a bad thing will happen. BOOM! >From the standpoint of static charge, Lancair IVs are conductive due to the carbon fiber. If you rub a balloon on a cat, both will become charged (one positive and one negative) and you will be lacerated. Most of the charge in the cat will transfer to you through the cats claws, aided by your blood (a good conductor). The balloon is another story. Because the balloon is not conductive, the charge remains in the localized areas that were rubbed on the cat. Because the balloon is non conductive, the charge cannot be drained off at a single point to create a spark. Because the balloon is non conductive, the charge cannot be drained off at a single point to create a spark. (worth repeating) One could argue that a 360 is a lot closer relative to a balloon than a chunk of aluminum. One could also argue that connecting the metal ring at the fuel filler to the other metal parts of the airplane would provide a path for an accumulated charge and would therefore be MORE likely to arc than an non-bonded (insulated) ring. IMHO it would be a good idea to have a convenient point to connect a ground strap to the airplane and be sure to use it whenever you are fueling. Regards Brent Regan Reflect on this "Stsaerb Egral Evil Gnol" >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://www.olsusa.com/Users/Mkaye/maillist.html Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>