CS-E 250 Fuel System

(a)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.

(b)Any characteristic of fuel conforming to the specification(s) to be approved 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.

(c)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. These means may be provided in the aircraft fuel system; in such case, the characteristics of the means shall be specified in the instructions for installation.

(d)It shall not be possible for fuel to drain into the Engine when it is not running, in such quantities as to introduce a risk of ‘hydraulicing’ or in any way adversely affect the mechanical reliability of the Engine.

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