Originally Posted by
Avionista
1. Earlier in this thread it was stated that Boeing introduced the MCAS system because, without it, the B737 MAX would not meet the requirements for passenger aircraft certification in respect of longitudinal stability. If this is true, should a fully functional MCAS be a specified item in the MEL as a mandatory requirement for release of the aircraft to revenue flights? Surely, if it was mentioned in the MEL both flight crew and engineering staff at Lion Air would have asked "What's this MCAS all about?". Is it normal for a system deemed necessary for certification of an aircraft not to be referenced in the MEL?
The MEL only lists items that may be inoperative before dispatch, provided certain limitations and procedures are observed. It does not list items that must be serviceable. The MEL or DDG typically includes a statement that says (in bold capital letters, as below):
"ALL ITEMS WHICH ARE RELATED TO THE AIRWORTHINESS OF THE AIRCRAFT AND ARE NOT INCLUDED ON THE LIST ARE AUTOMATICALLY REQUIRED TO BE OPERATIVE".