AD 2008-04-16

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Corrosion has been reported beneath the heat shield which is located around the APU (auxiliary power unit) exhaust outlet. Such corrosion could result in the fuselage being unable to sustain horizontal and vertical stabiliser loads. This is considered as potentially hazardous/catastrophic. * * *

The unsafe condition is that the horizontal or vertical stabilizer might collapse under excessive load, resulting in loss of control of the airplane. We are issuing this AD to require actions to correct the unsafe condition on these products.

Final rule.

2008-04-16 BAE Systems (Operations) Limited (Formerly British Aerospace Regional Aircraft): Amendment 39-15388. Docket No. FAA- 2007-29337; Directorate Identifier 2007-NM-150-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective April 3, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to BAE Systems (Operations) Limited Model BAe 146 and Model Avro 146-RJ airplanes; certificated in any category; all models, all serial numbers.

Subject

(d) Air Transport Association (ATA) of America Code 53: Fuselage.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Corrosion has been reported beneath the heat shield which is located around the APU (auxiliary power unit) exhaust outlet. Such corrosion could result in the fuselage being unable to sustain horizontal and vertical stabiliser loads. This is considered as potentially hazardous/catastrophic. This AD mandates inspections necessaryto address the identified unsafe condition.

The unsafe condition is that the horizontal or vertical stabilizer might collapse under excessive load, resulting in loss of control of the airplane. Corrective actions include repetitive detailed visual inspections for corrosion, pitted fasteners, or pillowing of the APU heat shield and surrounding skin and, if applicable, removal of the heat shield and repair.

Actions and Compliance

(f) Unless already done, do the following actions.
(1) Within 12 months after the effective date of this AD and thereafter at intervals not to exceed 24 months, perform a detailed visual inspection of the APU heat shield and surrounding skin, in accordance with paragraph 2.C. of BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-191, dated October 25, 2006.
(2) If any corrosion, pitted fastener, or pillowing is found during any detailed visual inspection required by paragraph (f)(1) of this AD, before the next flight, remove the APU heat shield and repair the affected area in accordance with paragraph 2.D. of BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-191, dated October 25, 2006.
(3) For any airplane modified in accordance with BAE Systems (Operations) Limited Modification Service Bulletin SB.53-193-60732A, dated November 1, 2006, the repetitive interval specified in paragraph (f)(1) of this AD may be extended to 48 months.

FAA AD Differences

Note: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(g) The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM-116, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Todd Thompson, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-1175; fax (425) 227-1149. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.
(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.
(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120- 0056.

Related Information

(h) Refer to MCAI European Aviation Safety Agency Airworthiness Directive 2007-0075, dated March 20, 2007; BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-191, dated October 25, 2006; and BAE Systems (Operations) Limited Modification Service Bulletin SB.53-193-60732A, dated November 1, 2006; for related information.

Material Incorporated by Reference

(i) You must use BAE Systems (Operations) Limited Inspection Service Bulletin ISB.53-191, dated October 25, 2006, to do the actions required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) For service information identified in this AD, contact British Aerospace Regional Aircraft American Support, 13850 Mclearen Road, Herndon, Virginia 20171.
(3) You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and RecordsAdministration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr- locations.html.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on September 28, 2007 (72 FR 55122). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

Corrosion has been reported beneath the heat shield which is located around the APU (auxiliary power unit) exhaust outlet. Such corrosion could result in the fuselage being unable to sustain horizontal and vertical stabiliser loads. This is considered as potentially hazardous/catastrophic. This AD mandates inspections necessary to address the identified unsafe condition.

The unsafe condition is that the horizontal or vertical stabilizer might collapse under excessive load, resulting in loss of control of the airplane. Corrective actions include repetitive detailed visual inspections for corrosion, pitted fasteners, or pillowing of the APU heat shield and surrounding skin and, if applicable, removal of the heat shield and repair. You may obtain further information by examining the MCAI in the AD docket.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.
We might also have requireddifferent actions in this AD from those in the MCAI in order to follow our FAA policies. Any such differences are highlighted in a NOTE within the AD.

Costs of Compliance

We estimate that this AD will affect about 1 product of U.S. registry. We also estimate that it will take about 2 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $160, or $160 per product.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. 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.
We are issuing this rulemaking under the authority described in "Subtitle VII, Part A, Subpart III, Section 44701: General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify this AD:
1. Is not a "significant regulatory action'' under Executive Order 12866;
2. Is not a "significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and
3.Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, under the authority delegated tome by the Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by adding the following new AD: