3. MMEL
Regulates dispatch of an aircraft
with inoperative equipment
Does not encourage operation
with inoperative equipment
Continued operation minimized
Limitations governing
repair intervals
4. MMEL
Most large aircraft are designed in
access of exceed airworthiness
requirements
Some equipment is not required
for all operations (eg. lights for
day)
Passenger convenience items
Items not included are to be
operative
5. MMEL
Approved or modified by authority
Required level of safety (FAR25) must be
maintained
Consequences of
further failure
Changes in crew
workload
Degradation in crew efficiency
Adverse weather conditions
6. MMEL
Substantiation to be achieved
adjustment of operating
limitations
transfer of the function
reference to other components
change in operating procedure
change in maintenance procedure
7. MMEL
Substantiation to be achieved
equipment considered optional
equipment considered redundant
qualitative safety analysis
quantitative analysis
8. MMEL - Approval
FOEB/JOEB
Manufactures, airlines, unions,
CAAs meet
Item by item review
Justification by manufacture
Operations and maintenance
procedures reviewed
9. MMEL - Approval
Foreign MMEL
Many States issue Supplement
Many accept as is
FAA create MMEL all US
Operated
Categorised MMELs
10. MMEL Format
Preamble
Four column format
Log of Revisions
Explanation of symbols
ATA Specification 100 code
Conditions in Remarks or Exceptions
column
11. MMEL Format
Placarding
“O” Operational Procedures
“M” Maintenance Procedures
Part of justification
Procedures not approved with MMEL
Boeing - Dispatch Deviation Guide
12. MMEL Prohibited Items
Not to include any item of equipment
which, if inoperative, is likely to
significantly affect performance of the
aircraft unless noted in the AFM and MEL.
No item shall be included in the MMEL which conflicts
with the limitations or invalidates the emergency
procedures of the AFM or of an airworthiness directive
unless the AFM or directive provide otherwise.
The MMEL shall not include any part or structural
component of the aircraft which is the subject of the
Configuration Deviation List (CDL).
14. CDL - Configuration
Deviation Lists
Amendment to type certificate
Not included in MEL
Limitations Section to Flight
Manual
Operation with Missing
Secondary Airframe Engine Parts
16. MEL DEFINITION
The MEL permits operation
of the aircraft under
specified conditions with
certain inoperative
equipment
The MEL is derived from the MMEL and is
applicable to an individual operator.
17. MEL INTENT
Operation of an aircraft
with aircraft equipment
inoperative or removed is
prohibited unless an
operator does so in
compliance with an
approved MEL
18. MEL LIMITATION
With the exception of Global
Changes, the content
of an operator's approved
MEL cannot be less restrictive
than the content of the approved
MMEL for that aircraft type.
19. GLOBAL CHANGES
Items that qualify as a GC are
generally those items that are
required to be installed by a new
regulatory requirement, or are
MMEL items that are affected by
CAA policy decisions..
20. AUDIT OF OPERATOR MELS
The ‘Authority’ should audit the
operator’s conformance to MEL
requirements on an ongoing
basis, and as part of any
company audit.
22. ADMINISTRATIVE
PROCEDURES
INITIAL APPLICATION INFORMATION
When an operator expresses the
intent to operate an aircraft eligible to
use an MEL, the ‘Authority’ should
provide them with:
the current requirements of the state;
a copy of the states MMEL/MEL Policy;
the revision status of the MMEL.
25. ADMINISTRATIVE
PROCEDURES
OPERATOR MEL DEVELOPMENT
The operator will develop their MEL and
amendments.
Must be a joint operations and
maintenance document
Based on the current MMEL revision.
Approved by senior company official from
Operations and Maintenance prior to the
MEL being submitted to the Authority for
approval.
26. ADMINISTRATIVE
PROCEDURES
SUBSTANTIATION
The operator must provide
substantiating documents to support
their MEL submissions. These
documents will provide additional
information relating to the operator’s
MEL program.
MEL items which do not appear in the
MMEL will require substantiation
27. AVIATION INSPECTOR
RESPONSIBILITY
OPERATIONS
The POI is responsible for vetting the
operator's MEL with respect to the
operations functions and procedures
Both Operations and Airworthiness
Inspectors must agree prior to an approval
being granted for an operator's MEL
application.
28. AVIATION INSPECTOR
RESPONSIBILITY
AIRWORTHINESS
The Principal Airworthiness Inspector
is responsible for vetting the operator's
MEL with respect to the maintenance
functions
Both Operations and Airworthiness
Inspectors must concur prior to an
approval being granted for an
operator's MEL application.
30. AVIATION INSPECTOR
RESPONSIBILITY
MEL DISTRIBUTION
Copies are required for:
each aircraft;
Senior Company Official - Maintenance;
Senior Company Official -Operations;
Dispatch (if applicable);
Maintenance Coordinator (if applicable);
any other personnel as required;
the ‘AUTHORITIES Library or Regional Office Library.
31. MEL AMENDMENTS
The operator must review their MEL on a
regular basis to ensure compliance with changes
to the operation, aircraft or to the Regulations.
A revision to the MMEL will require that the
operator review and amend their MEL, as
necessary.
The MEL program should be part of the
operator's quality assurance program.
33. CONFORMITY TO THE MMEL
MODIFICATION OF MMELS
Operators may request changes to their MEL .
These suggestions for changes, accompanied by
appropriate substantiation, should be forwarded
to the CAA for assessment.
The Authority may modify their MMEL where
appropriate, or
An operator may contact the manufacturer
directly with a request to review the MMEL.
34. CONFORMITY TO THE MMEL
MEL CONTENT
The operator's MEL must reflect the current
MMEL limitations unless otherwise authorized by a
change in the MMEL. When a revision is issued to
a MMEL, the operator's MEL need not be revised
if the change is less restrictive than the existing
MEL.
Except as noted above, all items installed in an
operator's aircraft which are addressed in the
most recent approved version of the MMEL, shall
be included in the MEL.
35. CONFORMITY TO THE MMEL
ADMINISTRATIVE CONTROL ITEMS
Operators may use their MEL as a document to
control items for tracking and information
purposes. Conditions apply:
MELs may include items not contained in the MMEL;
however,
• no relief may be granted unless conditions and
limitations are contained in an approved
document other than the MMEL
• may not include items or subsystems of items
which are addressed in the MMEL.
36. CONFORMITY TO THE MMEL
PASSENGER CONVENIENCE ITEMS
Passenger convenience items may
include items such as galley
equipment, entertainment,
and overhead reading
lamps. Passenger
convenience items do not carry a
specific repair interval, and need not be
listed in an operator's MEL, if they are not
addressed in the MMEL. The exceptions
to this rule are: (Continued)
37. CONFORMITY TO THE MMEL
PASSENGER CONVENIENCE ITEMS (Exceptions)
Where passenger convenience items serve a
second function, such as movie equipment being
used for cabin safety briefings, operators must
develop and include operational contingency
procedures in case of an equipment malfunction
Where passenger convenience items are part of
another aircraft system, for example - the
electrical system, procedures must be developed
and included in the MEL for deactivating and
securing in case of malfunction.
38. CONFORMITY TO THE MMEL
MEL AUDITS
Whenever an audit is conducted, the operator’s
MEL shall be reviewed. The review shall ensure
that the MEL conforms to current policies and
procedures.
Special attention should be given to operating
rules that may have been amended since the MEL
was last approved. It shall be confirmed that the
latest revisions to the MMEL, and any Global
Changes - if more restrictive, have been
incorporated into the MEL.
39. DISPATCH
"Dispatch" for the purpose of the MEL/MMEL
refers to the moment the airplane starts its
takeoff roll. In the case of a helicopter, it refers
to the moment the helicopter commences air or
ground taxi. The MEL is approved on the basis
that equipment will be operative for takeoff
unless the appropriate MEL procedures have
been carried out. (Cont.)
40. DISPATCH
The MEL shall include procedures to deal
with any failures which occur between the
start of taxi or push back and takeoff
brake release.
After takeoff commences, no MEL action
is required, until the completion of the
next landing.
41. DISPATCH
OPERATIONAL AND MAINTENANCE
ITEMS
Any item of equipment in the MEL, which when
inoperative would require an operating or
maintenance procedure to ensure the required
level of safety, shall be so identified in the
"remarks" or "exceptions" column of the MEL. This
will normally be "O" for an operating procedure,
and/or "M" for a maintenance procedure.
42. MELS FOR LEASED FOREIGN
AIRCRAFT
The MEL for a particular leased aircraft must
not be less restrictive than the locally
approved MMEL and must be approved by
the local authority. The country of registration
of the leased aircraft may require that their
aircraft be operated in accordance with their
approved MEL, in which case any less
restrictive changes to this MEL must be
approved by the foreign authority.(Cont.)
43. MELS FOR LEASED FOREIGN
AIRCRAFT
The local ‘Authority’ may require more
restrictive changes to the MEL because of
local regulations. It is the responsibility of
the local lessee to determine the
requirements of the foreign and ‘national’
authority for the use of a MEL on the leased
aircraft.
44. MELS FOR FOREIGN LEASED
(LOCALLY) REGISTERED AIRCRAFT
Some authorities review each lease and approves
or accepts the use of a MEL on such aircraft based
on whether a bilateral airworthiness agreement or
a technical arrangement exists between them and
the foreign regulatory authority and it has been
determined that the MMEL/MEL procedures are
acceptable.
If there is no agreement between the ‘authority’
and the foreign authority a review of the foreign
operator's MEL is conducted to determine that it is
consistent with the locally approved MMEL
46. ------------------------------------------------------------------------------------------
| TRANSPORT CANADA |
| MASTER MINIMUM EQUIPMENT LIST |
|----------------------------------------------------------------------------------------|
|AIRCRAFT: |REVISION NO: 07 |PAGE: |
| de Havilland DHC-6, Series 100, 200 & 300 |DATE: Sep. 18, 1998 |23-1 of 2 |
| |
|----------------------------------------------------------------------------------------|
| 1. | 2. NUMBER INSTALLED |
| SYSTEM & RIC | ----------------------------------------------------------|
| SEQUENCE | | 3. NUMBER REQUIRED FOR DISPATCH |
| NUMBERS | | ----------------------------------------------------|
|--------------------------| | | 4. REMARKS OR EXCEPTIONS |
|23 COMMUNICATIONS | | | |
| | | | |
|1 Communications D |- |- | Any in excess of those required by |
| Systems (VHF, | | | regulation and not powered by a standby or |
| HF, UHF) | | | emergency bus may be inoperative. |
| | | | |
|2 Passenger B |1 |0 |(O) May be inoperative provided: |
| Address System | | | a) alternate procedures are established |
| | | | and used, and |
| | | | b) required safety briefings are given to |
| | | | passengers using a means that will |
| | | | ensure the briefings are audible to |
| | | | each passenger. |
| All cargo D |1 |0 | |
| operation. | | | |
|3 Static C |- |- | One may be missing from the rudder and one |
| Discharge Wicks | | | from the right elevator. |
| | | | |
|4 Cockpit Speakers D |- |0 | May be inoperative provided headsets are |
|*** | | | installed and used by each person on |
| | | | flight deck duty. |
| | | | |
|5 Headsets and D |- |- | Only those in excess of those required for |
| Microphones | | | each flight deck crew member may be |
| | | | inoperative. |
| | | | |
|6 Pre-recorded D |- |0 |(O) Provided alternate procedures are |
| Passenger | | | established and used. |
|*** Announcement | | | |
4. REMARKS OR EXCEPTIONS
|23 COMMUNICATIONS | | |
| | | |
|1 VHF Comm Systems B | 2 | 1 | (o)Number two VHF may be unserviceable
| | | | provided number one VHF and the HF is
| | | | operative.
|2 HF Comm Systems D | 1 | 0 | May be unserviceable provided both
| | | |VHF are operative and VHF communications
| | | |can be maintained for the duration of the
| | |flight
MMEL - MEL EXAMPLE
47. ------------------------------------------------------------------------------------------
| TRANSPORT CANADA |
| MASTER MINIMUM EQUIPMENT LIST |
|----------------------------------------------------------------------------------------|
|AIRCRAFT: |REVISION NO: 06 |PAGE: |
| de Havilland DHC-6, Series 100, 200 & 300 | | |
| |DATE: Dec. 05, 1997 |22-1 of 1 |
|----------------------------------------------------------------------------------------|
| 1. | 2. NUMBER INSTALLED |
| SYSTEM & RIC | ----------------------------------------------------------|
| SEQUENCE | | 3. NUMBER REQUIRED FOR DISPATCH |
| NUMBERS | | --------------------------------------------------- |
|--------------------------| | | 4. REMARKS OR EXCEPTIONS |
|22 AUTOFLIGHT | | | |
| | | | |
|1 Autopilot C |1 |0 |(M) Provided: |
|*** | | | |
| | | | a) the controls are confirmed free, and |
| | | | |
| | | | b) the system is deactivated and |
| | | | secured. |
| | | | |
|
| D |1 |0 | Provided routine procedures do not require |
| | | | its use. |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
|----------------------------------------------------------------------------------------|
| 1. | 2. NUMBER INSTALLED |
| SYSTEM & RIC | ----------------------------------------------------------|
| SEQUENCE | | 3. NUMBER REQUIRED FOR DISPATCH |
| NUMBERS | | --------------------------------------------------- |
|--------------------------| | | 4. REMARKS OR EXCEPTIONS |
|22 AUTOFLIGHT | | | |
| | | | |
|1 Autopilot C |1 |0 |(M)(O) Provided: |
| | | | a) a qualified captain and co-pilot occupy |
| | | | the pilot positions, and two crew |
| | | operational procedures are available. |
| | | | b) the flight controls are confirmed free, |
| | | | c) the system is deactivated and |
| | | | secured. |
| | | | |
MMEL - MEL EXAMPLE
48. ------------------------------------------------------------------------------------------
| FLYRITE AIRLINES |
| R MINIMUM EQUIPMENT LIST |
|----------------------------------------------------------------------------------------|
|AIRCRAFT: |REVISION NO: 07 |PAGE: |
| de Havilland DHC-6, Series 100, 200 | | |
| |DATE: Oct. 18, 1998 |24-1 of 1 |
|----------------------------------------------------------------------------------------|
| 1. | 2. NUMBER INSTALLED |
| SYSTEM & RIC | ----------------------------------------------------------|
| SEQUENCE | | 3. NUMBER REQUIRED FOR DISPATCH |
| NUMBERS | | ----------------------------------------------------|
|--------------------------| | | 4. REMARKS OR EXCEPTIONS |
|24 ELECTRICAL POWER | | | |
| | | | |
|1 L GENERATOR and B |2 |1 |(O) Provided the corresponding loadmeter |
| R GENERATOR | | | operates normally. |
| Caution Lights | | | |
| | | | |
|2 A.C. Inverters B |2 |1 | One may be inoperative for day VMC. |
| | | | |
| B |2 |1 |(M) One may be inoperative for day or night |
| | | | provided flight instruments do not require |
| | | | A.C. power. |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
MEL
NOTE, The other equipment listed on the
MMEL is not fitted to Flyrite Aircraft
49. DDG
MEL 22-1 AUTOPILOT -
MAINTENANCE PROCEDURES
The Collins DHC6 autopilot system operates the control
system via electrically actuated capstans which are attached
to the main flying control cables by bridal cables. The
capstans are located in the aft fuselage and center wing
above the cabin lining.
Deactivation Procedures:
•Pull and tag the A/P CB located on the CB panel behind the
captains head,
•Remove the capstan bridal cables from the three A/P
capstans and control cables,
•Check all flying controls for full & free movement. (End)
51. Master Minimum Equipment List
Definitions
1. Systems Definitions: Systems numbers
are based on the Air Transport Association
(ATA) Specification Number 100 and items
are numbered sequentially.
a)"Item" (Column 1) means the
equipment, system, component, or function
listed in the "Item" column.
52. Master Minimum Equipment List
Definitions
b) "Number Installed" (Column 2) is the
number (quantity) of items normally installed
in the aircraft. This number represents the
aircraft configuration considered in
developing this MMEL. Should the number
be a variable (e.g., passenger cabin items) a
number is not required.
53. Master Minimum Equipment List
Definitions
"***" symbol in Column 1 indicates an item
which is not required by regulation but which
may have been installed on some models of
aircraft covered by this MMEL. This item may
be included on the operator's MEL if it has
been installed on one or more of the operator's
aircraft. The symbol shall not used in the
operator's MEL. The "***" symbol may be
considered equivalent to the term “if
installed”.
54. Master Minimum Equipment List
Definitions
c) "Number required for dispatch"
(Column 3) is the minimum number (quantity)
of items required for operation provided the
conditions specified in Column 4 are met.
Note:Where the MMEL shows a variable
number required for dispatch, the MEL must
reflect the actual number required for dispatch
or an alternate means of configuration control
approved by the Authority.
55. Master Minimum Equipment List
Definitions
d) "Remarks or Exceptions" (Column 4) in this
column includes a statement either prohibiting or
permitting operation with a specific number of
items inoperative, provisos (conditions and
limitations) for such operation, and appropriate
notes.
e) A "vertical bar" (change bar) in the margin
indicates a change, addition or deletion in the
adjacent text for the current revision of that page
only.
56. Master Minimum Equipment List
Definitions
g) “Master Minimum Equipment List”
means a document that establishes the aircraft
equipment allowed to be inoperative under
conditions specified therein for a specific type
of aircraft.
h) “Minimum Equipment List” means
an approved document that authorizes an
operator to dispatch an aircraft with aircraft
equipment inoperative under the conditions
specified therein.
57. Master Minimum Equipment List
Definitions
2. "Administrative Control Items" means
an item listed by the operator in the MEL for tracking
and informational purposes. It may be added to an
operator's MEL provided no relief is granted, or
provided conditions and limitations are contained in
an approved document such as the SRM. If relief
other than that granted by an approved document is
sought for an administrative control item, a request
must be submitted to the Authority. If the request
results in review and approval, the item becomes an
MMEL item rather than an administrative control
item.
58. Master Minimum Equipment List
Definitions
"Airplane/Rotorcraft Flight Manual" is the
document required for type certification and
approved by the Authority. The approved
AFM/RFM for the specific aircraft is listed on
the applicable Type Certification Data Sheet.
4. "Alphabetical symbol" in Column 4
indicates a proviso (condition or limitation) that
must be complied with for operation with the
listed item inoperative.
59. Master Minimum Equipment List
Definitions
5. "As Required by Regulation", "As
required by FAR", and other similar
statements mean that the listed item is subject
to certain provisions (restrictive or permissive)
expressed in such regulations as, the Federal
Aviation Regulations or the Airworthiness
Manual etc. Unless the MMEL provides
otherwise, the items specified by these
requirements must be operative.
60. Master Minimum Equipment List
Definitions
6. "Deleted" in the remarks column after a
sequence item indicates that the item was previously
listed but is now required to be operative if installed
in the aircraft.
7. "Deactivated and Secured" means that
the specified component must be put into an
acceptable condition for safe flight. An acceptable
method of deactivating and securing will be
established by the operator for inclusion in his/her
MEL.
61. Master Minimum Equipment List
Definitions
8. "Day of discovery" is the calendar day
an equipment/instrument malfunction was
discovered. This day is excluded from the
calendar days or flight days specified in the
MMEL for the repair of an inoperative item of
equipment, and is applicable to all MMEL
items in categories A,B,C, and D.
62. Master Minimum Equipment List
Definitions
9. "Engine Indicating Crew Alerting
System (EICAS), Electronic Centralized
Aircraft Monitoring System (ECAM) or
similar systems" that provide electronic
messages refer to a system capable of providing
different priority levels of systems information
messages (e.g., Warning, Caution, Advisory, Status
and Maintenance). An airplane discrepancy message
may or may not affect dispatchability Refer to the
specific MMEL for the aircraft type.
63. Master Minimum Equipment List
Definitions
10. "Excess Items" means those items
installed that are excess to the requirements
11."ETOPS" refers to extended range
operations of a two-engine airplane which has
a type design approval for ER operations and
complies with the provisions of the applicable
national requirements.
64. Master Minimum Equipment List
Definitions
12. "Federal Aviation Regulations
(FARs)" means the applicable portions of the
Federal Aviation Act and Federal Aviation
Regulations.
13."Flight Day" means a 24 hour period (e.g.
from midnight to midnight) - either Universal
Coordinated Time (UCT) or local time, as
established by the operator, during which at least one
flight is initiated for the affected aircraft.
65. Master Minimum Equipment List
Definitions
22. “Operating Instruction” Indicates operating
instructions that must be accomplished prior to
operation with the listed item inoperative, as per
"(O)" procedure above.
23. "Passenger Convenience Items" means
those items related to passenger convenience,
comfort or entertainment such as, but not limited to,
galley equipment, movie equipment, ash trays, stereo
equipment, overhead reading lamps, etc.
