Agency Finds Operators Have Been Exercising MEL Relief For STC Components Not Yet Evaluated Through The FOEB Process

FAA guidance requires that components, systems, or appliances installed on an aircraft under an STC be included in the MMEL before approval for inclusion in an operator’s MEL is allowed. Before inclusion in the MMEL, the Flight Operations Evaluation Board (FOEB) must evaluate an STC for such relief. The STC holder/applicant should request an FOEB evaluation as early as possible during the certification process. The STC applicant or aircraft operator involved in the certification of an STC should submit a request for MMEL relief in accordance with the FOEB MMEL Agenda Coordination Process. Refer to MMEL Policy Letter 109 for additional information.

In accordance with existing guidance, operators seeking to obtain MEL relief for components installed through an STC would either contact their principal inspectors (PIs) or the STC holder, or contact the Aircraft Evaluation Group (AEG) directly. Subsequently, upon application, the FOEB would then evaluate the STC and determine if MMEL/MEL relief is suitable. If relief is granted, the FOEB would revise the MMEL by listing that specific STC in the appropriate section. Once the STC is listed in the MMEL, operators may then revise their MELs to include that specific STC and exercise relief for that component, upon MEL approval from the principal operations inspector (POI).

Additionally, an aircraft manufacturer, operator, STC holder, or Industry Focal may initiate a subsequent request for a revision to an existing MMEL, in order to evaluate and incorporate STC relief. An aircraft operator that seeks MEL relief for a new item installed on its aircraft not currently listed in the MMEL may also contact the STC holder for MMEL relief support. The STC holder or operator who seeks MMEL relief will contact the responsible AEG to begin the FOEB process.

The FAA has recently discovered that operators were exercising MEL relief for STC components not yet evaluated through the FOEB process. This issue has gone undetected for a significant time, affecting numerous STCs. Many air carriers and operators have exercised MEL relief for a significant number of STCs without first getting concurrence from the AEG.

To rectify this matter, the FAA issued a policy deviation to all Safety Assurance (SA) offices until April 30, 2019. The policy deviation requires SA offices to request that the airline/operator provide, within 60 days, a complete listing of all STCs already installed that have not been evaluated for MMEL relief in accordance with the process stated in MMEL Policy Letter 109. Upon receipt of this list, SA offices will work cooperatively with the AEG offices to evaluate each STC for MMEL/MEL relief. During this deviation period, operators are authorized to continue exercising relief for installed STC components not yet evaluated by the FOEB. However, if at any time during the deviation period, a PI recognizes a safety hazard presented by existing MEL relief for an STC that has not yet been evaluated by the FOEB, the PI should take immediate action to remove such relief pending FOEB evaluation. AEG offices have also been granted a policy deviation to facilitate the efficient evaluation of these STCs.

Because of the accrual of STCs that need FOEB evaluation, the FAA has developed the following interim solution to avoid further accumulation of unevaluated MMEL/MEL relief for STCs and excessive delays for airlines/operators to exercise newly approved MMEL relief. Upon application and review, if the FOEB Chair evaluates proposed MMEL relief and finds that existing MMEL relief can be utilized without modification, the respective AEG office will issue a letter to the airline/operator. The letter will authorize that airline/operator to exercise immediate relief for the STC item without further amendment or approval of their existing MEL. When specialized relief is required to address the newly evaluated relief, the FOEB Chair will revise the MMEL with the relief listed under the respective ATA code along with the new provisos. Once the MMEL revision has been approved, then an operator can revise its MEL through the normal approval process. In this case, no letter will be issued by the AEG.

Applicants with components not yet installed on aircraft, or in the installation process may follow the process listed above. In these cases, MEL relief for the component(s) may be exercised only when either: 1) a letter has been issued by the AEG, authorizing relief for the item under the operator’s existing MEL; or 2) the MMEL is revised under the normal FOEB process and the operator’s MEL is also revised and approved accordingly. The FAA is continuing to research this matter and will issue a permanent solution in the future.

Air carriers and operators should review their MELs and evaluate their management of items already installed by STC to determine if they have been evaluated for MMEL relief. This review should be coordinated with the PI assigned to the oversight of their certificate. Air carriers and operators should be prepared to provide a list of STCs already installed but not evaluated by the FOEB process, to their PIs upon request. Operators should continue to follow the policy outlined in MMEL Policy Letter 109.

(Source: FAA)

FMI: InFO