CS-E 560  Fuel System

ED Decision 2007/015/R

(See AMC E 560)

(a)     (1)     Each fuel specification to be approved, including any additive, and the associated limitations in flow, temperature and pressure that ensure proper Engine functioning under all intended operating conditions must be declared and substantiated.

(2)     Any parameter of the fuel specification which is likely to adversely affect Engine functioning or durability must be identified so that, where necessary, Engine or rig testing using appropriate fuel may be conducted.

(3)     The Engine fuel pump must have a margin of capacity over the maximum Engine demand in the flight envelope consistent with the assumed aircraft installation specifications.

(b)     (1)     Filters, strainers or other equivalent means must be provided to protect the fuel system from malfunction due to contaminants. These devices must have the capacity to accommodate any likely quantity of contaminants, including water, in relation to recommended servicing intervals and, if provided, the blockage or by-pass indication system (see also CS-E 670).

(2)     Any main fuel filter or strainer provided between the Engine fuel inlet and any device having a significant function for the control of the thrust or power must have a means to permit indication of impending blockage of the filter or strainer either:

(i)      To the flight crew or

(ii)     To the maintenance crew, if it can be shown that the Engine will continue to operate normally with the levels of contamination specified, for a period equal to the inspection interval of the impending blockage indicator.

(c)      If a by-pass means is provided on any filter or strainer, it must be designed such that, if the filter or strainer element is completely blocked, fuel will continue to flow at an acceptable rate through the rest of the system. In addition:

(1)     The design of the by-pass must be such that, when it is in operation, the previously collected contaminants in the filter or strainer will not enter the Engine fuel system downstream of the filter or strainer.

(2)     The design of the fuel system must be such that, when the by-pass is open, operation on contaminated fuel does not result in a Hazardous Engine Effect.

(3)     If the maintenance action to be taken after by-pass operation is different from that following an indication of impending blockage, then indication of by-pass operation must be provided.

(d)     The fuel system must be designed so that any accumulation of likely quantities of water which may separate from the fuel will not cause Engine malfunctioning.

(e)     If icing can occur in the fuel system, continued satisfactory functioning of the Engine in such circumstances must be ensured without the need for any action by the flight crew. If compliance relies upon fuel anti-icing additives or other means incorporated in the aircraft fuel system, this must be declared under CS-E 30 together with a statement of the conditions which must be met.

(f)      Provision must be made near each fuel pressure connection provided for instrumentation so as to limit the loss of fluid in the event of a pipe Failure.

(g)     Design precautions must be taken against the possibility of errors and inadvertent or unauthorised changes in setting of all fuel control adjusting means.

[Amdt. No.: E/1]