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【范围】
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This Aerospace Recommended Practice (ARP) covers a brief discussion of the icing problem in
aircraft fuel systems and different means that have been used to test for icing. Fuel preparation
procedures and icing tests for aircraft fuel systems and components are proposed herein as a
recommended practice to be used in the aircraft industry for fixed wing aircraft and their operational
environment only. In the context of this ARP, the engine is not considered to be a component of the
aircraft fuel system, for the engine fuel system is subjected to icing tests by the engine manufacturer
for commercial and particular military applications.
1.1 Purpose:
The cold temperatures to which jet airplanes are exposed can have a detrimental effect upon the
fuel system and its components by causing water which is entrained in the fuel to form ice and clog
filter and screens or cause component or system malfunction. As a result, fuel flow to engines can
be slowed down or stopped altogether causing flameouts which pose a flight safety hazard. Even
though many aircraft normally operate with fuels treated with an anti-ice additive, (Reference 1),
there are times when fuel without this additive may be encountered. Consequently, fuel systems
should be tested with fuel that does not contain the anti-icing additive unless the airplane is
specifically restricted from operating without the additive. Because there is great disparity in the
requirements and procedures used to perform these icing tests as evidenced in military
specifications and aircraft industry reports, it is difficult to determine which testing procedure is the
best for a particular fuel system or component.
Therefore, this ARP recommends practices for icing tests for aircraft fuel systems and fuel system
components and helps avoid expensive overdesign and overtesting of a component or system while
insuring the reliability of a fuel system in icing conditions.strRefField
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