(R) Electrical Bonding of Aircraft Fuel Systems
|Publication Date:||1 December 2012|
This SAE Aerospace Information Report (AIR) is limited to the subject of aircraft fuel systems and the questions concerning the requirements for electrical bonding of the various components of the system as related to Static Electric Charges, Fault Current, Electromagnetic Interference (EMI) and Lightning Strikes (Direct and Indirect Effects).
This AIR contains engineering guidelines for the design, installation, testing (measurement) and inspection of electrical bonds.
The purpose of this document is to provide guidelines and references for electrical bonding of structure, fluid lines and components of an aircraft fuel system. These guidelines are related to the various potential electrical charges and currents that may be applied to various portions of the system as a result of the system operation or external sources.
SFAR 88 and the introduction of Amendment 102 to FAR 25.981, has resulted in an industry-wide thorough review of fuel tank safety for all commercial aircraft. Fuel tank electrostatics, lightning, fault current and associated bonding/grounding requirements are among the many areas evaluated. Additionally, electrical bonding and protection against static electricity must be designed to minimize accumulation of electrostatic charge that could cause human injury or ignition of flammable vapors (FAR 25.899).
Field of Application
The information included in this document is generally applicable to all types of vehicles subject to flight. As aircraft are built with greater use of composite materials, the concerns become greater as a result of the higher electrical resistance values for such material. These higher resistance values may result in higher voltages and currents under certain conditions.