05-24654. Thermal/Acoustic Insulation Installed on Transport Category Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

This action modifies the requirements for improved flammability characteristics of thermal/acoustic insulation used as replacements on airplanes manufactured before September 2, 2005. The FAA has recently been provided information that the rule will apply to a much broader range of components in currently operating airplanes than was originally intended. In addition, since publishing a final rule on July 31, 2003, the FAA has learned that some requirements for improved flammability covered materials do not have a significant effect on airplane fire safety. Further, in many cases, compliant replacements are not readily available. This action focuses the requirements on replacement materials that have a greater effect on safety and are readily available, and is necessary to avoid grounding of airplanes.

DATES:

This final rule is effective on January 30, 2006. Send your comments by February 28, 2006.

ADDRESSES:

Address your comments to the Docket Management System, U.S. Department of Transportation, Room Plaza 401, 400 Seventh Street, SW., Washington, DC 20590-0001. You must identify the docket number FAA-2005-23462 at the beginning of your comments, and you should submit two copies of your comments.

You may also submit comments through the Internet to http://dms.dot.gov. You may review the public docket containing comments to these regulations in person in the Dockets Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Dockets Office is on the plaza level of the NASSIF Building at the Department of Transportation at the above address. Also, you may review public dockets on the Internet at http://dms.dot.gov.

Privacy: We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. For more information, see the Privacy Act discussion in the SUPPLEMENTARY INFORMATION section of this document.

Docket: To read background documents or comments received, go to http://dms.dot.gov at any time or to Room PL-401 on the plaza level of the NASSIF Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Jeff Gardlin, FAA Airframe and Cabin Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone], facsimile [phone], e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA is adopting this final rule without prior notice and prior public comment. The Regulatory Policies and Procedures of the Department of Transportation (DOT) (44 FR 1134; February 26, 1979), however, provide that, to the maximum extent possible, operating administrations of the DOT should provide an opportunity for public comment on regulations issued without prior notice. Accordingly, we invite interested persons to participate in this rulemaking by submitting such written data, views, or arguments, as they may desire. We also invite comments relating to environmental, energy, federalism, or international trade impacts that might result from this amendment. Please include the regulatory docket or amendment number and send two copies to the address above. We will file comments received, as well as a report summarizing each substantive public contact with FAA personnel on this rulemaking, in the public docket. The docket is available for public inspection before and after the comment closing date.

Anyone is able to search the electronic form of all comments received into any of our dockets by the name of the individual submitting the comment (or signing the comment, if submitted on behalf of an association, business, labor union, etc.). You may review DOT's complete Privacy Act statement in the Federal Register published on April 11, 2000 (65 FR 19477) or you may visit http://dms.dot.gov.

The FAA will consider all comments received on or before the closing date for comments. We will consider late comments to the extent practicable. We may amend this final rule because of the comments received.

Commenters who want the FAA to acknowledge receipt of their comments submitted in response to this final rule must include a preaddressed, stamped postcard with those comments on which the following statement is made: “Comments to Docket No. FAA-2005-23462.” The postcard will be date-stamped by the FAA and mailed to the commenter.

Proprietary or Confidential Business Information

You should not file in the docket any information that you consider to be proprietary or confidential business information. Instead, you should send or deliver that information directly to the person identified under FOR FURTHER INFORMATION CONTACT. You must mark the information that you consider proprietary or confidential. If you send the information on a disk or CD ROM, mark the outside of the disk or CD ROM and also identify electronically within the disk or CD ROM the specific information that is proprietary or confidential.

Under Title 14 Code of Federal Regulations (CFR) 11.35(b), when we are aware of proprietary information filed with a comment, we do not place it in the docket. We hold it in a separate file to which the public does not have access and place a note in the docket that we have received it. If we receive a request to examine or copy this information, we treat it as any other request under the Freedom of Information Act (5 U.S.C. 552). We process such a request under the DOT procedures found in 49 CFR part 7.

Availability of Final Rule

You can get an electronic copy using the Internet by:

(1) Searching the Department of Transportation's electronic Docket Management System (DMS) Web page (http://dms.dot.gov/​search);

(2) Visiting the FAA's Regulations and Policies Web page at http://www.faa.gov/​regulations_​policies/​; or

(3) Accessing the Government Printing Office's Web page at http://www.gpoaccess.gov/​fr/​index.html.

You can also get a copy by sending a request to the Federal Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence Avenue SW, Washington, DC 20591, or by calling [phone]. Make sure to identify the docket number or amendment number of this rulemaking.

Small Business Regulatory Enforcement Fairness Act

The Small Business Regulatory Enforcement Fairness Act (SBREFA) of 1996 requires FAA to comply with small entity requests for information or advice about compliance with statutes and regulations within its jurisdiction. Therefore, any small entity that has a question regarding this document may contact their local FAA official, or the person listed under FOR FURTHER INFORMATION CONTACT. You can find out more about SBREFA on the Internet at our site, http://www.faa.gov/​regulations_​policies/​rulemaking/​sbre_​act/​.

Authority for This Rulemaking

The FAA's authority to issue rules regarding aviation safety is found in Title 49 of the United States Code. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority.

This rulemaking is promulgated under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, the FAA is charged with promoting safe flight of civil aircraft in air commerce by prescribing minimum standards required in the interest of safety for the design and performance of aircraft. This regulation is within the scope of that authority, because it prescribes new safety standards for the design of transport category airplanes.

Background

Previous Rulemaking

On September 20, 2000, we published Notice No. 00-09, which proposed to upgrade the flammability and fire protection standards for thermal/acoustic insulation installed in transport category airplanes (65 FR 56992). The notice contained a provision that would require thermal/acoustic insulation to comply with the proposed new standards when used as replacements on airplanes already in service, as well as requirements relating to newly manufactured airplanes. Notice No. 00-09 stated:

Amendments to parts 91, 121, 125, and 135 are proposed to require that insulation materials, when installed as replacements, meet the new flame propagation test requirements of § 25.856. This proposal would provide for the gradual attrition of earlier materials. Since there are existing materials that meet the proposed standards, and since those materials cost and weigh no more than other materials, this should result in no additional cost to operators.

While some commenters questioned whether there was any safety benefit in this provision, no commenters presented any information or data to contradict the assumptions made in establishing the provision. The requirement was adopted in the final rule, published on July 31, 2003, in §§ 91.613(b)(1), 121.312(e)(1), 125.113(c)(1), and 135.170(c)(1) (68 FR 45046). Operators were required to use replacement insulation materials meeting the requirements of § 25.856 after September 2, 2005. Our goal was to purge (operator and supplier) stocks of materials not meeting the new standards and encourage production of only those materials meeting the new standards. Because materials meeting the new standards were already available, the rule attributed no additional costs to this aspect of the requirements.

Basis of This Change

Following publication of the fnal rule, and the associated Advisory Circular (AC) 25.856-1, and shortly before the September 2, 2005, compliance date, industry representatives told us that some assumptions in the regulation were not correct. This information was not provided during the comment period for Notice No. 00-09, or during the 2-year period after the rules were published. While we make every effort to anticipate the complete impact of regulatory proposals, one of the purposes of the “notice and comment” process is to get information that we do not have. When affected parties do not comment on a regulation, or when they do comment, but do not raise issues of concern, we must assume the proposal is accurate. In this case, we did not receive inputs during the rulemaking process that would have alerted us to the issues. Nonetheless, now that we are aware of the issues, we recognize that further rulemaking is needed for several reasons.

First, thermal/acoustic insulation is used much more extensively in the fuselage than we originally understood. We did not consider whether compliant replacement parts could be efficiently produced for a significant number of parts installed on airplane models that are no longer in production. Unfortunately, no comments were received to address this provision, and it was not until recently that the extent of the difference between the actual situation and the assumed situation came to light.

Second, some materials needed to comply with the new requirements cost or weigh more than the materials they replace. This is particularly true for materials that are used to insulate certain equipment or provide acoustic attenuation in specialized applications. These materials are not replaced often, but a significant redesign would be required to adapt the associated parts to comply with the new requirements. Usually, these parts and materials are not maintained in large quantities of spares because they are not needed often. However, spares might be procured years in advance of the actual need.

Third, some insulation is integral to another part, and is not separately identified as “insulation.” Thus, an operator might inadvertently replace insulation while replacing another component and be out of compliance with the applicable rule. The affected component would not be readily identified in the spares inventory as being affected by the regulations because its primary function and identification were based on something other than thermal/acoustic insulation.

Lastly, certain types of insulation we thought were permanent are occasionally replaced. Airframe manufacturers reported that their records of supplying replacement insulation to operators showed they had never provided replacements for certain parts. However, in actual practice, many operators fabricate their own replacement insulation or procure it from a third party, using data supplied by the airframe manufacturer. All of these issues are complicated for airplane models that are no longer in production and for which replacement parts are not available from the original equipment manufacturer.

The issues discussed above do not apply to insulation “blankets.” Insulation blankets are defined as an encapsulated assembly consisting of a core insulating material and a moisture barrier film or cover surrounding the core. They represent the largest usage of thermal/acoustic insulation in the airplane and are, therefore, the most significant from a fire safety standpoint. Insulation blankets are most often used against the airplane fuselage structure but are also used around ducts and under floor panels. The materials used to construct compliant insulation blankets are widely available and can be readily adapted to different applications, even for airplane models no longer in production. The flammability performance of insulation blankets was the primary impetus behind development of the new test standards. The materials in insulation blankets were one of the primary materials intended to be covered by the “replacement” provision in the regulation.

In addition, insulation around ducts is significant for its potential fire safety ramifications. Ducts are intended to convey a fluid medium from one point to others and, therefore, provide a potential fire propagation path by their nature. Because air ducts are the most significant and common, we are limiting the replacement provision in this amendment to insulation air ducts only. Therefore, other types of piping, or fluid lines are no longer covered by the replacement provision. These items, which might otherwise be considered ducts, are not included in this amendment because they have very specialized insulation needs, and replacement parts are not readily available. In addition, they tend to be much smaller than air ducts and do not use the large quantity of insulation that was the target of the original proposal.

While some ducts and insulation are integral, meaning that replacement of the insulation includes the replacement of the duct, many ducts are insulated with separate materials. The July 2003 rule will continue to apply to those ducts insulated with separate material. However, insulation that is integral to the duct and cannot be replaced without replacing the duct, will no longer be covered by the regulations for replacement. This includes insulation that is bonded or laminated to the surface of the duct. Such insulation that is the subject of airworthiness directives must still be replaced in accordance with those airworthiness directives.

This amendment changes only the replacement portion of the July 2003 rule. This rule does not affect newly manufactured airplanes. Airframe manufacturers have worked diligently to achieve compliance for newly manufactured airplanes and all the affected parts have been addressed. However, for the reasons noted above, a change is necessary to address unforeseen issues with availability of replacement parts for older airplanes.

Affect on Safety

This change does not have a significant affect on safety. The original intent of the “replacement” provision in the regulations was to promote the future production only of materials that comply with 14 CFR 25.856(a) as replacements. We understood that the primary thermal/acoustic insulation subject to replacement was of blanket construction. The regulation was worded generally however, and therefore covered any type of thermal/acoustic insulation when it is replaced. As noted earlier, the most significant insulation from a fire safety standpoint is insulation in blanket form, and insulation on ducts. Replacement of these materials with compliant materials will reduce the potential for fire propagation. However, for other, less extensive materials, a piecemeal replacement with compliant materials has very little, if any safety benefit.

Paperwork Reduction Act

There are no new requirements for information collection associated with this amendment.

International Compatibility

In keeping with U.S. obligations under the Convention on International Civil Aviation, it is FAA policy to comply with International Civil Aviation Organization (ICAO) Standards and Recommended Practices to the maximum extent practicable. The FAA determined there are no ICAO Standards and Recommended Practices that correspond to these regulations.

Good Cause for Immediate Adoption

Sections 553(b)(3)(B) and 553(d)(3) of the Administrative Procedures Act (APA) (5 U.S.C. 553(b)(3)(B) and 553(d)(3)) authorize agencies to dispense with certain notice procedures for rules when they find “good cause” to do so. Under section 553(b)(3)(B), the requirements of notice and opportunity for comment do not apply when the agency for good cause finds those procedures are “impracticable, unnecessary, or contrary to the public interest.” Section 553(d)(3) allows an agency, upon finding good cause, to make a rule effective immediately, thereby avoiding the 30-day effective date requirement in section 553.

The FAA finds notice and public comment on this final rule are impracticable. For the APA, “impracticable” means if notice and comment procedures were followed, they would defeat the purpose of the rule. This final rule must be adopted promptly to create the certainty and the time needed by operators to schedule and conduct maintenance, and to avoid grounding of airplanes. Coordinating and issuing rulemaking documents will take time under current procedures. The delay associated with notice and comment would negate the relief offered in this final rule, since operators would have to incur great expense to prepare for eventual replacement of thermal/acoustic insulation and associated components for which no current design meeting the new standards exists. Therefore, any delay in issuing this final rule would subject affected operators to confusion and the expense of trying to comply without the necessary design information and, in some cases, availability of appropriate materials. Therefore, it is “impracticable” to provide notice and opportunity to comment.

Executive Order 12866 and DOT Regulatory Policies and Procedures

Executive Order 12866, Regulatory Planning and Review, directs the FAA to assess both the costs and benefits of a regulatory change. We are not allowed to propose or adopt a regulation unless we make a reasoned determination that the benefits of the intended regulation justify its costs. Our assessment of this rule indicates its economic impact is minimal. Since its costs and benefits do not make it a “significant regulatory action,” as defined in the Order, we have not prepared a “regulatory impact analysis.” Similarly, we have not prepared a “regulatory evaluation,” which is the written cost/benefit analysis ordinarily required for all rulemaking under the DOT Regulatory and Policies and Procedures. We do not need to do the latter analysis where the economic impact of a rule is minimal.

Regulatory Evaluation, Regulatory Flexibility Analysis, International Trade Impact Assessment, and Unfunded Mandates Assessment

Changes to Federal regulations must undergo several economic analyses. First, Executive Order 12866 directs that each Federal agency shall propose or adopt a regulation only upon a reasoned determination that the benefits of the intended regulation justify its costs. Second, the Regulatory Flexibility Act of 1980 requires agencies to analyze the economic impact of regulatory changes on small entities. Third, the Trade Agreements Act (19 U.S.C. 2531-2533) prohibits agencies from setting standards that create unnecessary obstacles to the foreign commerce of the United States. In developing U.S. standards, this Trade Act requires agencies to consider international standards and, where appropriate, to be the basis of U.S. standards. Fourth, the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) requires agencies to prepare a written assessment of the costs, benefits, and other effects of proposed or final rules that include a Federal mandate likely to result in the expenditure by State, local, or tribal governments, in the aggregate, or by the private sector, of $100 million or more annually (adjusted for inflation). This portion of the preamble summarizes the FAA's analysis of the economic impacts of this final rule.

DOT Order 2100.5 prescribes policies and procedures for simplification, analysis, and review of regulations. If the expected cost impact is so minimal that a proposal does not warrant a full evaluation, this order permits a statement to that effect. The basis for the minimal impact must be included in the preamble, if a full regulatory evaluation of the cost and benefits is not prepared. Such a determination has been made for this rule. The reasoning for that determination follows.

This rule narrows the scope of the requirement to use only replacement thermal/acoustic insulation meeting the standards adopted in 14 CFR 25.856(a) for airplanes manufactured before September 2, 2005. The original requirement was sufficiently broad that operators could have been out of compliance, even without realizing it. Those operators would have been subject to fines and they would have experienced maintenance schedule disruptions. By narrowing the scope of the requirement, operators can comply with reasonable effort, and the safety intent of the original rules is preserved. Although we cannot provide a quantitative estimate of the losses resulting from the fines and maintenance schedule disruptions, we believe these would have been significant. Further, there will be a decrease in overall paperwork and costs since fewer part numbers will have to be tracked and updated. Finally operators will be able to focus on the most significant thermal/acoustic insulation materials and ensure their inventories are updated accordingly.

The FAA has, therefore, determined this rulemaking action is not a “significant regulatory action” as defined in section 3(f) of Executive Order 12866, and is not “significant” as defined in DOT's Regulatory Policies and Procedures. In addition, the FAA has determined that this rulemaking action: (1) Will not have a significant economic impact on a substantial number of small entities; (2) will not affect international trade; and (3) will not impose an unfunded mandate on State, local, or tribal governments, or on the private sector.

This rule simply focuses the compliance requirement for replacement materials on those that have a significant safety impact and eliminates a burdensome requirement on those replacement materials that do not. Thus, this rule maintains the benefits of the existing rule and reduces costs.

Regulatory Flexibility Analysis

The Regulatory Flexibility Act of 1980 (RFA) establishes “as a principle of regulatory issuance that agencies shall endeavor, consistent with the objective of the rule and of applicable statutes, to fit regulatory and informational requirements to the scale of the business, organizations, and governmental jurisdictions subject to regulation.” To achieve that principle, the RFA requires agencies to consider flexible regulatory proposals, to explain the rationale for their actions, and to solicit comments. The RFA covers a wide range of small entities, including small businesses, not-for-profit organizations and small governmental jurisdictions.

Agencies must perform a review to determine whether a proposed or final rule will have a significant economic impact on a substantial number of small entities. If the agency determines that it will, the agency must prepare a regulatory flexibility analysis as described in the RFA.

However, if an agency determines that a proposed or final rule is not expected to have a significant economic impact on a substantial number of small entities, section 605(b) of the RFA provides the head of the agency may so certify and a regulatory flexibility analysis is not required. The certification must include a statement providing the factual basis for this determination, and the reasoning should be clear.

This rule narrows the scope of the requirement to use only replacement thermal/acoustic insulation meeting the standards adopted in 14 CFR 25.856(a), for airplanes manufactured before September 2, 2005. As the rule narrows the scope of compliance, it provides cost relief for airplane operators.

Therefore, as the FAA Administrator, I certify that the rulemaking action will not have a significant economic impact on a substantial number of small entities.

International Trade Impact Assessment

The Trade Agreements Act of 1979 prohibits Federal agencies from establishing any standards or engaging in related activities that create unnecessary obstacles to the foreign commerce of the United States. Legitimate domestic objectives, such as safety, are not considered unnecessary obstacles. The statute also requires consideration of international standards and, where appropriate, that these international standards be the basis for U.S. standards. The FAA has assessed the potential effect of this rulemaking action and has determined that it will provide cost relief for all United States and foreign commercial operators of United States registered airplanes. Thus this rule reduces costs to both domestic and international entities and has a neutral trade impact.

Unfunded Mandates Assessment

The Unfunded Mandates Reform Act of 1995 (the Act) is intended, among other things, to curb the practice of imposing unfunded Federal mandates on State, local, and tribal governments. Title II of the Act requires each Federal agency to prepare a written statement assessing the effects of any Federal mandate in a proposed or final agency rule that may result in an expenditure of $100 million or more (adjusted annually for inflation) in any one year by State, local, and tribal governments, in the aggregate, or by the private sector. The FAA currently uses an inflation-adjusted value of $120.7 million in lieu of $100 million.

This final rule does not contain such a mandate. The requirements of Title II do not apply.

Executive Order 13132, Federalism

The FAA has analyzed this final rule under the principles and criteria of Executive Order 13132, Federalism. We determined that this action will not have a substantial direct effect on the States, or the relationship between the National Government and the States, or on the distribution of power and responsibilities among the various levels of government. We therefore determined that this final rule does not have federalism implications.

Plain English

Executive Order 12866 (58 FR 51735, Oct. 4, 1993) requires each agency to write regulations that are simple and easy to understand. We invite your comments on how to make these regulations easier to understand, including answers to questions such as the following:

• Are the requirements in the regulation clearly stated?
• Does the regulation contain technical language or jargon that interferes with their clarity?
• Would the regulation be easier to understand if it was divided into more (but shorter) sections?
• Is the description in the preamble helpful in understanding the regulation?

Please send your comments to the address specified in the ADDRESSES section.

Environmental Analysis

FAA Order 1050.1D defines FAA actions that may be categorically excluded from preparation of a National Environmental Policy Act (NEPA) environmental impact statement. In accordance with FAA Order 1050.1D, appendix 4, paragraph 4(j), this final rule qualifies for a categorical exclusion.

Regulations That Significantly Affect Energy Supply, Distribution, or Use

The FAA has analyzed this final rule under Executive Order 13211, Actions Concerning Regulations that Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May 18, 2001). We have determined it is not a “significant energy action” under the executive order because it is not a “significant regulatory action” under Executive Order 12866, and it is not likely to have a significant adverse effect on the supply, distribution, or use of energy.

Lists of Subjects

14 CFR Part 91

• Aircraft
• Aviation safety
• Reporting and recordkeeping requirements

14 CFR Part 121

• Aircraft
• Aviation safety
• Reporting and recordkeeping requirements
• Safety
• Transportation

14 CFR Part 125

• Aircraft
• Aviation safety
• Reporting and recordkeeping requirements

14 CFR Part 135

• Aircraft
• Aviation safety
• Reporting and recordkeeping requirements

The Amendments

In consideration of the foregoing, the Federal Aviation Administration amends Chapter 1 of Title 14 Code of Federal Regulations, as follows:

PART 91—GENERAL OPERATING AND FLIGHT RULES

1. The authority citation for part 91 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40103, 40113, 40120, 44101, 44111, 44701, 44709, 44711, 44712, 44715, 44716, 44717, 44722, 46306, 46315, 46316, 46502, 46504, 46506-46507, 47122, 47508, 47528-47531.

2. Amend § 91.613 by revising paragraph (b)(1) to read as follows:

§ 91.613

Materials for compartment interiors.

* * * * *

(b) Thermal/acoustic insulation materials. For transport category airplanes type certificated after January 1, 1958:

(1) For airplanes manufactured before September 2, 2005, when thermal/acoustic insulation is installed in the fuselage as replacements after September 2, 2005, the insulation must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003, if it is:

(i) Of a blanket construction or

(ii) Installed around air ducting.

* * * * *

PART 121—OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS

3. The authority citation for part 121 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 40119, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-44717, 44722, 44901, 44903-44904, 44912, 46105.

4. Amend § 121.312 by revising paragraph (e)(1) to read as follows:

§ 121.312

Materials for compartment interiors.

* * * * *

(e) Thermal/acoustic insulation materials. For transport category airplanes type certificated after January 1, 1958:

(1) For airplanes manufactured before September 2, 2005, when thermal/acoustic insulation is installed in the fuselage as replacements after September 2, 2005, the insulation must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003, if it is:

(i) Of a blanket construction or

(ii) Installed around air ducting.

* * * * *

PART 125—CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 6,000 POUNDS OR MORE

5. The authority citation for part 125 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44705, 44710-44711, 44713, 44716—44717, 44722.

6. Amend § 125.113 by revising paragraph (c)(1) to read as follows:

§ 125.113

Cabin interiors.

* * * * *

(c) Thermal/acoustic insulation materials. For transport category airplanes type certificated after January 1, 1958:

(1) For airplanes manufactured before September 2, 2005, when thermal/acoustic insulation is installed in the fuselage as replacements after September 2, 2005, the insulation must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003, if it is:

(i) of a blanket construction or

(ii) Installed around air ducting.

* * * * *

PART 135—OPERATING REQUIREMENTS: COMMUTER AND ON-DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT

7. The authority citation for part 135 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44705, 44709, 44711-44713, 44715-44717, 44722.

8. Amend § 135.170 by revising paragraph (c)(1) to read as follows:

§ 135.170

Materials for compartment interiors.

* * * * *

(c) Thermal/acoustic insulation materials. For transport category airplanes type certificated after January 1, 1958:

(1) For airplanes manufactured before September 2, 2005, when thermal/acoustic insulation is installed in the fuselage as replacements after September 2, 2005, the insulation must meet the flame propagation requirements of § 25.856 of this chapter, effective September 2, 2003, if it is:

(i) Of a blanket construction, or

(ii) Installed around air ducting.

* * * * *

Issued in Washington, DC on December 22, 2005.

Marion C. Blakey,

Administrator.