05-19437. Airworthiness Directives; BAE Systems (Operations) Limited Model ATP Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain BAE Systems (Operations) Limited Model ATP airplanes. This AD requires doing an inspection of each bolt attaching the aft isolators to both engine subframes and replacing bolts if necessary. This AD results from reports of failures of the bolts attaching the aft isolators to the engine subframe. We are issuing this AD to prevent failure of the bolts attaching the aft isolators to the engine subframe, which may result in an engine separating from the airplane.

DATES:

This AD becomes effective October 19, 2005.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of October 19, 2005.

We must receive comments on this AD by December 5, 2005.

ADDRESSES:

Use one of the following addresses to submit comments on this AD.

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: 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.

Contact British Aerospace Regional Aircraft American Support, 13850 Mclearen Road, Herndon, Virginia 20171, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT:

Todd Thompson, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Discussion

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, notified us that an unsafe condition may exist on certain BAE Systems (Operations) Limited Model ATP airplanes. The CAA advises that in-service failures of the bolts attaching the aft isolators to the engine subframe have been reported. Testing has demonstrated that reduced torque loading has an adverse effect on the fatigue life of the bolts attaching the aft isolators to the engine subframe. Failure of all bolts in the bolt group will affect the ability of the engine subframe to control the effects of resonance and whirl flutter. This condition, if not corrected, could result in an engine separating from an airplane.

Relevant Service Information

BAE Systems (Operations) Limited has issued Service Bulletin ATP-54-20, dated July 29, 2003. The service bulletin describes procedures for performing a visual inspection for missing or failed bolts that attach aft isolator brackets to both engine subframes, replacing all four bolts on an engine subframe if any bolt is missing or failed on that engine subframe, and reporting results. The replacement includes doing a torque check of each bolt, checking the dimensions of the bolt holes, and contacting the manufacturer if the holes are not within tolerance. The service bulletin also notes that quick engine change unit subframes should be inspected prior to installation.

The CAA mandated the service information and issued British airworthiness directive G-2004-0001, dated January 22, 2004, to ensure the continued airworthiness of these airplanes in the United Kingdom.

FAA's Determination and Requirements of This AD

This airplane model is manufactured in the United Kingdom and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. We have examined the CAA's findings, evaluated all pertinent information, and determined that we need to issue an AD for products of this type design that are certificated for operation in the United States.

Therefore, we are issuing this AD to prevent failure of the bolts attaching the aft isolators to the engine subframe, which may result in an engine separating from the airplane. This AD requires accomplishing the actions specified in the service information described previously, except as discussed under “Differences Among the AD, the Service Bulletin, and the British Airworthiness Directive.”

Differences Among the AD, the Service Bulletin, and the British Airworthiness Directive

The service bulletin specifies to contact the manufacturer for instructions if holes are not within tolerance, but this AD would require repairing those conditions using a method that we or the CAA (or its delegated agent) approve. In light of the type of repair that would be required to address the unsafe condition, and consistent with existing bilateral airworthiness agreements, we have determined that, for this AD, a repair we or the CAA approve would be acceptable for compliance with this AD.

The service bulletin refers only to a “visual inspection.” We have determined that the procedures in the service bulletin should be described as a “detailed inspection.” Note 1 has been included in this AD to define this type of inspection.

Interim Action

We consider this AD interim action. If final action is later identified, we may consider further rulemaking then.

Costs of Compliance

None of the airplanes affected by this action are on the U.S. Register. All airplanes affected by this AD are currently operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, we consider this AD necessary to ensure that the unsafe condition is addressed if any affected airplane is imported and placed on the U.S. Register in the future.

The following table provides the estimated costs to comply with this AD for any affected airplane that might be imported and placed on the U.S. Register in the future.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts cost	Cost per airplane
Inspection, per inspection cycle	1	$65	None	$65, per inspection cycle.

FAA's Determination of the Effective Date

No airplane affected by this AD is currently on the U.S. Register. Therefore, providing notice and opportunity for public comment is unnecessary before this AD is issued, and this AD may be made effective in less than 30 days after it is published in the Federal Register.

Comments Invited

This AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any relevant written data, views, or arguments regarding this AD. Send your comments to an address listed in the ADDRESSES section. Include “Docket No. FAA-2005-22562; Directorate Identifier 2004-NM-60-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD that might suggest a need to modify it.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of that web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

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 have 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 that the regulation:

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. See the ADDRESSES section for a location to examine the regulatory evaluation.

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 to me 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.

§ 39.13

[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

2005-20-09 BAE Systems (Operations) Limited (Formerly British Aerospace Regional Aircraft): Amendment 39-14303. Docket No. FAA-2005-22562; Directorate Identifier 2004-NM-60-AD.

Effective Date

(a) This AD becomes effective October 19, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to BAE Systems (Operations) Limited Model ATP airplanes, certificated in any category; on which modification 35256A (BAE Systems (Operations) Limited Service Bulletin ATP-54-10) has been accomplished.

Unsafe Condition

(d) This AD results from reports of failures of the bolts attaching the aft isolators to the engine subframe. We are issuing this AD to prevent failure of the bolts attaching the aft isolators to the engine subframe, which may result in an engine separating from the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Inspection and Replacement

(f) At the later of the times specified in paragraphs (f)(1) and (f)(2) of this AD: Do a detailed inspection for missing or failed bolts that attach aft isolator brackets to both engine subframes in accordance with the Accomplishment Instructions of BAE Systems (Operations) Limited Service Bulletin ATP-54-20, dated July 29, 2003. Repeat the inspection thereafter at intervals not to exceed 2,000 flight cycles.

(1) Within 2,000 flight cycles after the last torque check of the bolts attaching the aft isolator brackets to both engine subframes done in accordance with BAE Systems (Operations) Limited Service Bulletin ATP-54-20.

(2) Within 300 flight cycles after the effective date of this AD.

Note 1:

For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”

(g) If any bolt is missing or failed on any engine subframe during the inspection required by paragraph (f) of this AD: Before further flight, replace all bolts on that engine subframe in accordance with the Accomplishment Instructions of BAE Systems (Operations) Limited Service Bulletin ATP-54-20, dated July 29, 2003. If any bolt holes on any engine subframe are not within the tolerance specified in the service bulletin: Before further flight, repair according to a method approved by either the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or the Civil Aviation Authority (CAA) (or its delegated agent).

Parts Installation

(h) As of the effective date of this AD, no person may install a quick engine change unit subframe on any airplane, unless the subframe has been inspected in accordance with paragraph (f) of this AD.

No Reporting Requirement

(i) Although the service bulletin referenced in this AD specifies to submit certain information to the manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with 14 CFR 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(k) British airworthiness directive G-2004-0001, dated January 22, 2004, also addresses the subject of this AD.

Material Incorporated by Reference

(l) You must use BAE Systems (Operations) Limited Service Bulletin ATP-54-20, dated July 29, 2003, to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact British Aerospace Regional Aircraft American Support, 13850 Mclearen Road, Herndon, Virginia 20171, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov;​; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call [phone], or go to http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on September 20, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.