Reader Feedback

The MMEL Trap?

I am writing in regard to a June, 2007, commercial edition article by Howie Fuller. While I certainly agree that, "...Master Minimum Equipment Lists (MMEL) are among the finest contributions to aviation safety...." I must take issue with several points raised in the article.

First, Howie’s assertion that "the MEL is only an advisory document and that the regulation prevails in any conflict" is not true. 14 CFR 91.213, in part, states that an MEL constitutes a supplemental type certificate for the aircraft. 14 CFR 121.628, in part, states that an MEL constitutes an approved change to the type design without requiring recertification. Consequently, an FAA approved operator MEL provides the legal authority to operate the airplane with certain equipment inoperative, and is certainly not "an advisory document."

There may be inspectors out there that will question specific items in an operator’s MEL; however, if the MEL is in compliance with the FAA Master MEL that should alleviate any concern the inspector has with the operator. From that point, any further concern the inspector has with a particular MMEL item should be taken to the FAA Aircraft Evaluation Group (AEG) that has responsibility for that aircraft type. The assigned Flight Operations Evaluation Board (FOEB) chairman will certainly evaluate the concern and issue an MMEL revision if appropriate.

The article raises a specific concern about anti-collision lights with regard to the requirements of 14 CFR 91.209. Since the MEL constitutes an STC (Part 91) and an approved change to type design (Part 121), the aircraft is no longer equipped or certified with anti-collision lights and doesn’t have to meet the requirements of 91.209(b).

Do operators need to revise their MEL coverage for anti-collision lights (in advance of any MMEL revision)? In my opinion, no, they do not. Do they need to self-disclose past deferrals of anti-collision lights? Again, in my opinion, no, they do not. Will we see MMELs revised to comply with 91.209(b)? Maybe, maybe not. Any FAA decision to do so will be based on a careful analysis of the effect of the failure, the next critical failure and associated/applicable operational and certification rules. I am not aware of any push within AEG to address MMEL relief for anti-collision lights.

Howie and Aviation Maintenance staff or readers may be interested to know of the existence of the FAA/ATA MMEL Industry Group. The MMEL IG is a joint FAA/industry group that meets quarterly to tackle a wide range of dispatch-related issues raised by Part 91, 121 and 135 operators and then works to develop MMEL policy to address those issues. Recent MMEL IG meeting agenda items include non-essential equipment and furnishings (NEF), ELT, EFB, nav databases, passenger seats and cargo restraints (among many others). Our goal is to ensure that when FAA issues MMEL policy it not only provides the highest level of safety, but at the same time also allows operators to maintain their aircraft at a high state of dispatch readiness. In addition to MMELs and MMEL policy letters, several MMEL IG documents, including our charter and MMEL revision and proposal process, as well as meeting info can be found on www.opspecs.com (yes, all free!).

Tom Atzert

United Airlines

Operational Engineering – MEL

Co-Chairman – FAA/ATA MMEL Industry Group

Watch for Howie Fuller’s response to the above letter in next month’s magazine. — Ed.