2 Advisory

US. Department =

sree Circula

Administration

Subject: INSTALLATION, REMOVAL, OR CHANGE Date: 11/6/85 AC No: 45-3
OF IDENTIFICATION DATA AND Initiated by: aws-200 © Change:

IDENTIFICATION PLATES ON AIRCRAFT ENGINES

1. PURPOSE. This advisory circular (AC) provides information and guidance
concerning the installation, removal, or change of identification data and
identification plates on aircraft engines. This AC identifies an acceptable
means, but not the only means, of compliance with Federal Aviation Regulations
Part 45.

2. RELATED FEDERAL AVIATION REGULATIONS (FAR) SECTIONS. Sections 43.3, 43.9,
43.11, 45.11, and 45.13.

3. BACKGROUND. FAR Section 45.11 sets forth the requirements for each aircraft
engine manufactured under a type or production certificate to be identified by
means of a fireproof identification (ID) plate. FAR Section 45.13 requires
specific identification information on the ID plate. The identification
information includes the name of the builder, the model designation, the
builder's serial number, the type certificate mmber (if any), production
certificate number (if any), and the established rating. The Federal Aviation
Administration (FAA) requires the use of identification plates and the data
contained thereon to identify the specific FAA approved engine configuration and
the fact that it was mamfactured and approved under the provisions of an FAA
production approval. Additionally, the regulations require that the
identification plate be affixed to the engine at an accessible location, and in
such a manner that it will not likely be defaced or removed during normal
service, or lost or destroyed in an accident.

4. DISCUSSION.

a. Problems have arisen, since the advent of the turbine engine modular
concept, with respect to engine identificatio. A significant feature of
turbine engines is that separate sections (known as modules) are devoted to
particular functions. A typical engine consists of a compressor section,
combustion section, turbine section, and exhaust section. These modules are not
independently approved by the FAA, but are approved as a part of the complete
engine type design.

b. Aircraft engine manufacturers in compliance with FAR Sections 45.11 and
45.13 identify each complete engine by affixing an engine ID plate to one of the
modules. That engine ID plate does not identify the module but does serve to
identify the assembly of modules that make up the complete engine approved under
a type certificate. That module therefore serves only as a vehicle on which to
affix the engine ID plate.

a


AC 45-3 11/6/85

c. When the module to which the engine ID plate is affixed requires
replacement, the ID plate would need to be removed and reinstalled on the
replacement module in order to maintain the identification of the engine. This
is analogous to an aircraft, when the member to which the aircraft ID plate is
affixed is damaged, the ID plate would be removed from the damaged member and
reinstalled on the replacement member since that ID plate serves to identify the
aircraft, not the member to which it is affixed.

d. Maintenance on modular engines is normally accomplished by replacing
entire modules. However, there is a need to maintain a continuous history on
the basic engine (notwithstanding that every module may have been replaced any
mumber of times) which is predicated on the engine ID plate, serial number, and
historical/modification records. Additionally, modular type engines also
contain a number of non-modular components (e.g., fuel lines, accessories, etc.)
which are controlled by the engine serial number on the ID plate and
corresponding historical/modification records.

e. The FAA is aware that some aircraft operators/repair stations do not
remove the engine ID plate fram the module to which it is affixed when the
particular module is: (1) DAMAGED AND MUST BE REPLACED; and, (2) REMOVED FOR
MAINTENANCE AND WILL NOT BE REINSTALLED ON THE ENGINE FROM WHICH IT WAS REMOVED.
Similarly, they install replacement modules on which an engine ID plate
(belonging to another engine assembly) is affixed. This essentially constitutes
an exchange of ID plates resulting in a loss of identity (historical/
modification data) for both engines, as well as being in noncompliance with
FAR Section 45.13(c) and/or (e). The changing of engine ID plates, including
serial numbers fram engine to engine, or failure to remove and reinstall engine
ID plates when the module to which they are attached is required to be removed
for maintenance, inhibits positive control of both modular and non-modular
components. This control is needed, since the engine ID plate and the
information contained thereon provides positive correlation between the engine
and the required historical/modification records. The engine ID plate also
serves as a baseline to control all activity accomplished on a particular engine
(i.e., configuration, AD compliance, overhaul, life limited parts,
noise/emission, module changes, compliance, etc.) throughout the entire service
life of the engine.

5. GENERAL INFORMATION.

a. Except as otherwise provided for in FAR 45.13(d) no person may remove,
change, or place the identification information (required by FAR 45.13(a)) on an
engine ID plate, or remove or install any engine ID plate (required by
FAR 45.11) without the approval of the Administrator.

b. FAR 45.13(b) prohibits the unauthorized removal, change, or placement of
identification information required by FAR 45.13(a) on any aircraft engine.
However, FAR 45.13(d)(1) authorizes removal, change, or replacement of the
identification information required by FAR 45.13(a) on any engine but only when
it is necessary and accomplished by persons performing work under the provisions
of FAR Part 43. The change of identification information would be considered
necessary when accomplished in compliance with specific maintenance procedures
contained in manufacturer's manuals, letters, or bulletins including those that
are incorporated in and made a part of an airworthiness directive.


11/6/85 AC 45-3

c. FAR 45.13(c) provides an exception, whereby persons performing
maintenance under the provisions of FAR Part 43, maintenance, preventive
maintenance, rebuilding, and alteration, may remove the identification plate
required by FAR Section 45.11 when necessary during maintenance operations.

(1) Removal of an ID plate would be considered necessary during certain
maintenance operations such as caustic cleaning, paint removal, or sandblasting.
Removal of an ID plate would also be considered necessary when the structure to
which the ID plate is fastened has to be repaired or replaced for maintenance
purposes.

(2) An engine ID plate removed during maintenance operations must be
reinstalled on the same engine in the original location from which it was
removed prior to releasing the engine to service.

(3) An engine ID plate cannot be replaced by persons performing
maintenance under the provisions of FAR 43 without the approval of the
Administrator.

a. The engine ID plate, when permanently affixed, serves at all times as
the control for establishing and maintaining the engine approval status.
Accordingly, the identification plate installed by the engine manufacturer must
remain with the particular engine throughout its useful life unless otherwise
authorized by the Administrator.

6. PROCEDURE. When the module to which the engine ID plate is affixed is
removed from an engine, and it is to be replaced with another module that is
new, or that has been repaired or overhauled, the engine ID plate shall be
transferred from the module that was removed to the module installed in its
Place. Upon completion of the module and engine ID plate change, an entry mist
be made in the maintenance record as required by FAR Sections 43.9 and 43.11.

7. OTHER METHODS. It should be recognized that methods other than those
described in this AC may be implemented when they are found acceptable to the
Administrator.

Willian 3.4sullivan

Acting Deputy Director of Airworthiness

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