14 CFR · Part 25
14 CFR § 25.973
Fuel tank filler connection.
Each fuel tank filler connection must prevent the entrance of fuel into any part of the airplane other than the tank itself. In addition—
(a)
[Reserved]
(b)
Each recessed filler connection that can retain any appreciable quantity of fuel must have a drain that discharges clear of each part of the airplane;
(c)
Each filler cap must provide a fuel-tight seal; and
(d)
Each fuel filling point must have a provision for electrically bonding the airplane to ground fueling equipment.
Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.
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