Definition
The procedure of electrically connecting an aircraft to the earth (or to a fuel truck that is itself connected to the earth) before fueling, in order to drain off any static electrical charge that has built up on either the aircraft or the fuel delivery equipment. This prevents a static spark from igniting fuel vapors during the fueling process.
Plain English
Before putting fuel into an aircraft, you connect it by a wire to the ground so any static electricity safely flows away. This stops a spark from setting fuel vapor on fire while you are fueling.
Context Anchor
Used during aircraft refueling, especially before opening fuel caps or starting fuel flow.
Derivation
From 'ground,' meaning the earth itself. In electrical work, connecting something to the earth gives stray electrical charge somewhere harmless to flow. The aviation use is the same idea applied to fueling.
Why Pilots Care
Prevents static sparks that could ignite fuel vapors and cause fire or explosion.
Intuition Check
Grounding does not mean the aircraft is being kept from flying here. In this context, it means giving static electricity a safe path away during fueling.
Example Sentence 1
Before fueling the aircraft, the line crew attached the grounding cable to the exhaust pipe.
Example Sentence 2
In dry windy conditions the crew double-checked the grounding connection to ensure all static charge had dissipated.