1. Purpose of This Notice. This notice announces revised policy
associated with Master Minimum Equipment List (MMEL) Policy Letter (PL)-98,
Navigation Databases. This notice provides guidance to the Aircraft Evaluation
Division (AFS-100), which develops and revises MMELs, and aviation safety inspectors
(ASI) with minimum equipment list (MEL) oversight responsibility, and tasks
them with ensuring all MMELs and operators’ MELs are updated in accordance with
this notice and MMEL PL-98, revision 1. This notice also extends the due date
for ASIs and AFS-100 to ensure compliance with MMEL PL-98, revision 1.
Note: The use of the term “operator” in this notice refers to those certificate
holders, program managers, foreign air carriers, and aircraft owners utilizing
an MMEL or MEL and conducting aircraft operations under Title 14 of the Code
of Federal Regulations (14 CFR) parts
91 subpart K
unless otherwise specified.
2. Audience. The primary audience for this notice is ASIs assigned
to AFS-100, and ASIs in Flight Standards offices with oversight responsibility
of aircraft operators’ MEL(s). The secondary audience includes all Flight Standards
divisions, branches, and offices.
3. Where You Can Find This Notice. You can find this notice on
the MyFAA employee website at
Inspectors can access this notice through the Flight Standards Information Management Systems (FSIMS) at
Operators can find this notice on the Federal Aviation Administration’s (FAA) website at
This notice is available to the public at
4. Cancellation. This notice cancels Notice N 8900.424, Master
Minimum Equipment List Policy Letter 98, Revision 1, Navigation Databases, and
Associated Aviation Safety Inspector Requirements, dated June 1, 2017.
a. General. The FAA established MMEL relief for out of currency
navigation databases on January 20, 1999, through MMEL PL-98, revision 0. In
general, the PL allowed MMEL relief and continued use of an out of currency
navigation database (without an existing inoperative condition) as long as the
operator verified the data used before flight. The PL allowed for repair category
C, which is up to 10 days deferral and one-time extendable for another 10 days by the operator.
Note: The use of the word “item” throughout this notice refers to both
instrument and equipment items, as applicable.
b. Regulatory Requirements. Part
129.14(b); and part
Inoperable Instruments and Equipment, in pertinent part, allow
for the continued operation of an aircraft with inoperable items installed through
the use of an FAA-approved MEL. For any item to be considered for relief under
this regulation, including a navigation database, the item must be inoperative.
c. Definition of Inoperative. Every MMEL and MEL must include
the definitions found in MMEL PL-25, MMEL and MEL Definitions. In PL-25, “inoperative”
is defined as “a system and/or component malfunction to the extent that it does
not accomplish its intended purpose and/or is not consistently functioning normally
within its approved operating limit(s) and/or tolerance(s).” An out of currency
navigation database that continues to be used for navigation does not fall within
the definition of inoperative and cannot be considered as such.
d. Preamble. Every MMEL and MEL must include the preamble found
in MMEL PL-34, MMEL and MEL Preamble (MMEL PL-36, FAR Part 91 MEL Approval & Preamble, contains the preamble for part
PL-34 (and PL-36) states, in pertinent part, “The individual
operator’s MEL, when approved and authorized, permits operation of the aircraft
with inoperative equipment.” Because the out of currency navigation database
is not inoperative per the definition, the preamble requirements cannot be complied
with and MMEL/MEL relief cannot be applied.
e. Operations Specification (OpSpec)/Management Specification (MSpec)/Training
Specification (TSpec)/Letter of Authorization (LOA) D095. Per 14 CFR, an
approved MEL, as authorized by OpSpec/MSpec/TSpec/LOA D095, Minimum Equipment
List AuthorizationU.S.-Registered Aircraft, is an approved change in type design
without requiring recertification of the aircraft. Because an out of currency
navigation database is not an inoperative item, there is no resultant change
in type design. It cannot be authorized MEL relief per OpSpec/MSpec/TSpec/LOA D095.
6. Guidance. All ASIs must be familiar with and understand the
limitations associated with conducting flight operations utilizing an out of
currency navigation database. ASIs must clearly understand that minimum system
capabilities and operating margins are based on specific levels of system performance
that includes a current navigation database. An operator’s ability to conduct
terminal and en route Area Navigation (RNAV) procedures and Required Navigation
Performance (RNP) procedures will be limited within national and international
airspace if their navigation database is not current. All ASIs should review
the current editions of the following advisory circulars (AC) and remain alert
for the publication of the updated guidance associated with current navigation
Airworthiness Approval of Positioning and Navigation Systems (chapters 8, 10, 12, and appendix 2).
Acceptance of Aeronautical Data Processes and Associated Databases (paragraph 13).
U.S. Terminal and En Route Area Navigation (RNAV) Operations (paragraphs 10 and 11).
Approval Guidance for RNP Procedures with AR (appendices 35).
Approval Guidance for RNP Operations and Barometric Vertical
Navigation in the U.S. National Airspace System and in Oceanic and Remote Continental
Airspace (chapter 8, and appendices A and B).
a. AFS-100. AFS-100 will revise all MMELs that contain navigation
database relief to ensure compliance with MMEL PL-98, revision 1, at either
the next revision or within 2 years (24 months) of the effective date of this
notice, whichever comes earlier. AFS-100 managers and the Air Transportation
Division (AFS-200) will monitor to ensure compliance to this requirement.
(1) Inspectors will ensure that operators with approved out of currency navigation
database relief revise/update their MEL/MMEL for compliance with MMEL PL-98,
revision 1. This shall be completed within 90 days after AFS-100 has revised
the applicable MMEL’s navigation database relief. Normal MEL revision approval
procedures will be used to record the completion of this requirement. Responsible
Flight Standards office managers will monitor using internal office procedures
to ensure compliance to this requirement.
(2) Review operator procedures for aircraft operation with an out of currency
navigation database. If deficiencies are identified, ASIs will work with the
operator to achieve an acceptable level of compliance with the database currency
requirements found in the aforementioned ACs. In many, if not most cases, operator
procedures developed for MEL compliance to MMEL PL-98, revision 0, should be
acceptable for continued use.
8. Disposition. The information in this notice will not be incorporated
into FAA Order 8900.1. MMEL PL-98, revision 1, will remain in effect until revised
or rescinded. Direct questions concerning the information in this notice to
AFS-200 at 202-267-8166.
ORIGINAL SIGNED by
/s/ John Barbagallo
Deputy Executive Director, Flight Standards Service