This advisory circular (AC) describes an acceptable means for showing
compliance with the applicable airworthiness regulations for the management of open
problem reports (OPRs) in technical standard order (TSO) authorization and type
certification for the system, software, and airborne electronic hardware (AEH) domains.
This document contains guidance that is not legally binding in its own right nor will be
relied upon by the Department of Transportation or the Federal Aviation Administration
as a separate basis for affirmative enforcement action or other administrative penalty.
Moreover, conformity with this guidance document (as distinct from existing statutes and
regulations) is voluntary only, and nonconformity will not affect rights and obligations
under statutes and regulations. This document is intended only to provide clarity to the
public regarding existing requirements under the law or agency policies. However, if you
use the means described in this AC, you should follow it in all applicable respects unless
alternate means are proposed and accepted by the FAA.

This advisory circular (AC) provides “best practices” for the management
of open problem reports, and is intended to complement AC 20-189, Management of
Open Problem Reports (OPRs). This document contains guidance that is not legally
binding in its own right nor will be relied upon by the Department of Transportation or
the Federal Aviation Administration as a separate basis for affirmative enforcement
action or other administrative penalty. Moreover, conformity with this guidance
document (as distinct from existing statutes and regulations) is voluntary only, and
nonconformity will not affect rights and obligations under statutes and regulations. This
document is intended only to provide clarity to the public regarding existing requirements
under the law or agency policies.
2.

This AC provides information
on the hazards and risks of in-flight fires on transport category aircraft. The information
includes recommended crewmember procedures and training for combating general and
high-energy fires (HEF) caused by lithium batteries. This AC is applicable to operators
certificated under Title 14 of the Code of Federal Regulations (14 CFR) parts 91,
91 subpart K (part 91K), 121, 125, and 135. This guidance is not legally binding in its
own right and will not be relied upon by the Federal Aviation Administration (FAA) as a
separate basis for affirmative enforcement action or other administrative penalty.
Conformity with the guidance is voluntary only and nonconformity will not affect rights
and obligations under existing statutes and regulations.

Ozone-depleting substances, including chlorofluorocarbons (CFCs), have been shown to deplete
the Earth’s stratospheric ozone layer resulting in adverse environmental damage and health effects by
exposing the Earth to the sun’s harmful ultraviolet radiation as well as contributing to global climate
change. Concerns about the formation of an “ozone hole” over the Antarctic in the early 1980s led to
the signing of an international agreement, the Montreal Protocol on Substances that Deplete the Ozone
Layer, in 1987 (Montreal Protocol). The Kigali Amendment was adopted to phase down the
production and consumption of hydrofluorocarbons (HFCs) worldwide, in addition to CFCs, in 2016.
The Montreal Protocol and the national laws implementing it are working. Ozone-depleting
substances in the atmosphere have begun to decrease, and Earth’s protective ozone layer is showing
signs of recovery. In recent years, new regulations have also expanded to tracking and mitigating
fugitive emissions from greenhouse gases that are non-ozone-depleting substitutes as well.

This notice supplements Federal Aviation Administration (FAA)
Order 8100.15B, Organization Designation Authorization Procedures, by providing instructions
and procedures intended to eliminate or minimize ODA holder interference with UMs
performing their authorized functions and to ensure free communication between UMs and the
FAA. The notice also updates certain instructions and procedures for FAA personnel in
evaluating applications submitted for ODA under the procedural requirements set forth in
Title 14 of the Code of Federal Regulations (14 CFR) part 183 subpart D and conducting
oversight of ODA holders approved under subpart D. To the extent that this notice conflicts with
Order 8100.15B, the contents of this notice supersede the order.