FAA Aviation Mechanic Airframe (AMA)Fuel, Cabin and Ice Control SystemsMedium
During fuel truck refueling of a transport-category aircraft, a technician connects a bonding cable between the fuel truck and the aircraft before opening the fuel port. What hazard does this bonding procedure primarily prevent?
- AAccumulation of static electrical potential difference that could cause a spark and ignite fuel vapors
- BFuel siphoning caused by pressure differential during refueling
- CIncorrect fuel grade from being loaded into the aircraft tank
- DCorrosion between dissimilar metals at the fuel port connection
Show answer & explanationAnswer & explanation
Correct answer: A. Accumulation of static electrical potential difference that could cause a spark and ignite fuel vapors
Bonding equalizes the electrical potential between the fuel truck and aircraft, preventing a static discharge spark that could ignite flammable fuel vapors present during refueling operations.
Why the other options are wrong
- B. Siphoning is unrelated to electrical bonding procedures.
- C. Fuel grade verification is a separate procedural check, unrelated to bonding.
- D. Bonding is an electrical safety measure, not a corrosion prevention method.
Fuel System Bonding/Grounding
Electrical bonding between fueling equipment and the aircraft equalizes electrical potential to prevent static discharge sparks during refueling.
- Prevents ignition of fuel vapors from static discharge
- Required before opening fuel caps or connecting hoses
- Aircraft and fuel truck are also grounded to earth ground
Memory trick: Bond before you pour—no spark near the vapor.