IRImplementing rule
CS 25J993 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 aeroplane 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 an APU 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.
[Amdt 25/1]
IR — CS-25 · ED Decision 2005/006/R · CS-25 Easy Access Rules · EAR revision 26 Jan 2023