---
kind: "section"
citation: "14 C.F.R. § 25.993"
title: "14"
number: "25.993"
heading: "Fuel system lines and fittings."
url: "https://uscodex.org/cfr/14/25.993"
---

# §25.993. Fuel system lines and fittings.

- (a) Each fuel line must be installed and supported to prevent excessive vibration and to withstand loads due to fuel pressure and accelerated flight conditions.
- (b) Each fuel line connected to components of the airplane between which relative motion could exist must have provisions for flexibility.
- (c) Each flexible connection in fuel lines that may be under pressure and subjected to axial loading must use flexible hose assemblies.
- (d) Flexible hose must be approved or must be shown to be suitable for the particular application.
- (e) No flexible hose that might be adversely affected by exposure to high temperatures may be used where excessive temperatures will exist during operation or after engine shut-down.
- (f) Each fuel line within the fuselage must be designed and installed to allow a reasonable degree of deformation and stretching without leakage.

## Notes

### Amendments

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-15, 32 FR 13266, Sept. 20, 1967]

### Authority

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).

### Source

Source: Docket No. 5066, 29 FR 18291, Dec. 24, 1964, unless otherwise noted.

### Amendments

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-15, 32 FR 13266, Sept. 20, 1967]