14 CFR § 25.973 - Fuel tank filler connection.
---
identifier: "/us/cfr/t14/s25.973"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 25.973 - Fuel tank filler connection."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "25.973"
section_name: "Fuel tank filler connection."
chapter_name: "FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "AIRCRAFT"
part_number: "25"
part_name: "AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 106(f), 106(g), 40113, 44701, 44702 and 44704; Pub. L. 115-254, 132 Stat 3281 (49 U.S.C. 44903 note)."
regulatory_source: "Docket No. 5066, 29 FR 18291, Dec. 24, 1964, unless otherwise noted."
cfr_part: "25"
---
# 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.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-40, 42 FR 15043, Mar. 17, 1977; Amdt. 25-72, 55 FR 29785, July 20, 1990; Amdt. 25-115, 69 FR 40527, July 2, 2004]