What is the difference between bonding and grounding in aircraft electrical systems?

• A. Bonding creates low impedance connections between parts to equalize voltage; grounding ties the system to earth to provide fault return paths and static discharge.
• B. Bonding ties system to earth; grounding equalizes voltage.
• C. Bonding connects to the aircraft skin only; grounding is not used.
• D. Bonding and grounding are the same process.

Answer: (A)

Bonding ensures that all metallic parts that could come into contact or influence each other are kept at the same electrical potential by low-impedance connections. This equalizes voltage between components and prevents unexpected sparks, arcing, or interference when equipment operates. Grounding, meanwhile, provides a reference path to earth and a safe route for fault currents to return and for static charges to be discharged through the airframe. In aircraft practice, bonding eliminates voltage differences between parts, while grounding offers a fault-return path and static dissipation. The other descriptions mix up these roles or claim they’re the same, which isn’t accurate.