Disposition of Unsalvageable Date: 7/5/94 AC No: 21-38

Aircraft Parts and Materials Initiated by: AIR-200 Change:

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1. PURPOSE. This advisory circular (AC) provides information

and guidance to persons involved in the sale, maintenance, or

disposal of aircraft parts. It provides information and guidance

to prevent unsalvageable aircraft parts and materials from being

sold as serviceable parts and materials. It provides one means,

but not the only means, of complying with 14 CFR part 21,

Certification Procedures for Products and Parts, requirements for

control of rejected parts and materials.

2. RELATED FEDERAL AVIATION REGULATIONS AND ADVISORY CIRCULARS.

a. 14 CFR part 21, Certification Procedures for Products and

Parts.

b. Advisory Circular 20-62, Eligibility, Quality, and

Identification of Approved Aeronautical Replacement Parts,

provides information on control of aeronautical replacement

parts.

c. Advisory Circular 21-29, Detecting and Reporting

Suspected Unapproved Parts, provides information and guidance for

detecting and reporting suspected unapproved parts.

3. BACKGROUND. It is common practice for possessors of aircraft

parts to dispose of unsalvageable parts and materials by selling,

discarding, or transferring such items. In some instances, these

items have reappeared for sale and in the active parts

inventories of the aviation community. Misrepresentation of the

status of parts and material and the practice of making such

items appear serviceable have resulted in the use of

unsalvageable nonconforming parts and materials.

4. TYPES OF PARTS AND MATERIALS THAT MAY BE MISREPRESENTED.

Persons disposing of unsalvageable aircraft parts and materials
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should consider the possibility of such parts and materials later

being misrepresented and sold as serviceable parts and materials.

Caution should be exercised to ensure that the following types of

parts and materials are disposed of in a manner that does not

allow them to be returned to service:

a. Parts with non-repairable defects, whether visible or not

to the naked eye.

b. Parts that are not within the specifications set forth by

the approved design, and cannot be brought into conformance with

applicable specifications.

c. Parts and materials for which further processing or

rework cannot make them eligible for certification under a

recognized certificate holder's system.

d. Parts subjected to unacceptable modification or rework

that is irreversible.

e. Life-limited parts that have reached or exceeded their

life limits, or have missing or incomplete records.

f. Parts that cannot be returned to airworthy condition due

to exposure to extreme forces or heat.

g. Principal structural elements (PSE) removed from a

high-cycle aircraft for which conformity cannot be accomplished

by complying with the applicable aging aircraft airworthiness

directives.

5. METHODS TO PREVENT MISREPRESENTATION OF UNSALVAGEABLE PARTS

AND MATERIALS.

a. Persons disposing of unsalvageable aircraft parts and

materials should, when appropriate, mutilate those parts and

materials prior to release. Mutilation should be accomplished in

such a manner that the parts become unusable for their original

intended use. Mutilated parts should not be able to be reworked

or camouflaged to provide the appearance of being serviceable,

such as by re-plating, shortening and re-threading long bolts,

welding, straightening, machining, cleaning, polishing, or

repainting.

(1) Mutilation may be accomplished by one or a

combination of the following procedures, but is not limited to:

(a) Grinding.

(b) Burning.

(c) Removal of a major lug or other integral feature.

(d) Permanent distortion of parts.

(e) Cutting a hole with cutting torch or saw.

(f) Melting.

(g) Sawing into many small pieces.
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(2) The following procedures are examples of mutilation

that are often less successful because they may not be

consistently effective:

(a) Stamping (such as a stamped "R" on a part).

(b) Spraying with paint.

(c) Hammer marks.

(d) Identification by tag or markings.

(e) Drilling small holes.

(f) Sawing in two pieces. Persons who rework

unsalvageable parts and materials may be highly skilled

technicians and have been known to rejoin parts cut in two pieces

in such a manner that the mutilation proves difficult to detect.

b. Persons disposing of unsalvageable aircraft parts and

materials may choose to release those parts for legitimate

non-flight uses, such as for training and education, research and

development, or for non-aviation applications. In such

instances, mutilation may not be appropriate. The following

methods should be used to prevent misrepresentation:

(1) Permanently marking or stamping the parts, subparts,

and material as "NOT SERVICEABLE." (Ink stamping is not an

acceptable method);

(2) Removing original part number identification;

(3) Removing data plate identification;

(4) Maintaining a tracking or accountability system, by

serial number or other individualized data, to record transferred

unsalvageable aircraft parts and materials; and

(5) Including written quality assurance procedures

concerning disposition and disposal of such parts and materials

in any agreement or contract transferring such parts and

materials.

NOTE: Unsalvageable or expired life-limited parts and

materials should not be released to any person or

organization who may end up placing the parts and

materials back in actual use, due to the criticality of

part and material failure and the potential safety

threat.

c. Organizations handling unsalvageable or expired

life-limited aircraft parts and materials should establish secure

areas in which to segregate such items from active serviceable

inventories and to prevent unauthorized access. Caution should

be exercised to ensure that these parts and materials receive the

appropriate final disposition.

d. Manufacturers producing approved aircraft parts should

maintain records of serial numbers for "retired" life-limited or

other critical parts. In such cases, the owner who mutilates
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applicable parts is encouraged to provide the original

manufacturer with the data plate and/or serial number and final

disposition of the part.

e. All purchasers of aircraft parts and materials should

ensure that misrepresented unsalvageable parts and materials are

not received into active inventory. The following are examples

of conditions to be alert for when receiving parts:

(1) "New" parts showing signs of rework.

(2) Used parts showing signs of unapproved or

inappropriate repair.

(3) Parts with poor workmanship or signs of rework in

the area of the part number or serial number inscription.

(4) Used parts lacking verifiable documentation of

history and FAA approval.

(5) Parts with prices "too good to be true."

(6) Questionable part numbers, fraudulent or suspicious

Technical Standard Order or FAA-Parts Manufacturer Approval

markings and/or re-identification, stamp-overs or vibro-etching

on the data plate.

(7) Parts delivered with photocopied or missing

maintenance release tags.

(8) Parts with a finish that is inconsistent with

industry standards (e.g., discoloration, inconsistencies,

resurfacing).

(9) New parts sold with maintenance release tags

reflecting a status other than new.

(10) Parts with poor documentation exhibiting incomplete

or inconsistent part identity information.

(11) Intact "scrap" unsalvageable parts offered in bulk

weight for prices higher than for mutilated parts with identical

weight and content.

6. SUSPECTED UNAPPROVED PART(s) (SUP). Suspected unapproved

parts should be reported via the FAA Form 8120-11, SUP

Notification, or the Aviation Safety Hotline toll free number,

800-255-1111, as referenced in AC 21-29, Detecting and Reporting

Suspected Unapproved Parts.

MICHAEL GALLAGHER

Acting Director, Aircraft
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Certification Service