The difference between MEL penalties and ECL restrictions for the same failure, can be clarified as
follows:
MEL: The requirements in the MEL are, amongst others, based on a (next critical) en-route failure, after dispatching the aircraft with the respective component unserviceable.
ECL: In flight, procedures are based on the assumption that the next critical failure, during that particular flight, will not occur. The manufacturer,s Operations Manual, AOM and ECL procedures
are therefore based on different criteria than the DDG.
When consulting the MEL in flight, it should be realized that restrictions in the MEL are only applicable for (the next) departure. Safety of the flight is fully covered by the applicable ECL procedure directives.
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