Airworthiness directives: Boeing,

[Federal Register: August 8, 2007 (Volume 72, Number 152)]

[Proposed Rules]

[Page 44433-44435]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr08au07-17]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28884; Directorate Identifier 2007-NM-116-AD]

RIN 2120-AA64

Airworthiness Directives; Boeing Model 727 Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for all Boeing Model 727 airplanes. This proposed AD would require repetitive external high frequency eddy current (HFEC) inspections of the crown skin for cracks at certain stringer attachment holes, and repair if necessary. This proposed AD results from a report of cracks at multiple locations on certain areas of the crown skin. We are proposing this AD to detect and correct fatigue cracks of the crown skin, which could result in rapid decompression of the airplane.

DATES: We must receive comments on this proposed AD by September 24, 2007.

ADDRESSES: Use one of the following addresses to submit comments on this proposed 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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

Fax: (202) 493-2251.

Hand Delivery: Room W12-140 on the ground floor of the West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for the service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Berhane Alazar, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6577; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number ``FAA-2007- 28884; Directorate Identifier 2007-NM-116-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

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 proposed 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 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 Operations office between 9

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Operations office (telephone (800) 647-5527) is located on the

[[Page 44434]]

ground level of the West 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.

Discussion

We have received a report indicating that fatigue tests resulted in cracks at multiple locations on the 727 body section 43 and 46 crown skin between stringers 11L and 11R. The first fatigue test cracks were found at approximately 66,000 simulated flight cycles. Subsequent inspection by Boeing on in-service airplanes also revealed similar crown skin cracks. In-service cracks were found on airplanes with between 71,236 and 81,234 total flight cycles. Fatigue cracks of the crown skin, if not detected and corrected, could result in rapid decompression of the airplane.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003. The service information describes procedures for repetitive external high frequency eddy current (HFEC) inspections of the crown skin for cracks at stringer attachment holes between stringer 11L and stringer 11R and from body station (BS) 259.5 to BS 1183, and repair of any crack. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under ``Differences Between the Proposed AD and Referenced Service Information.''

Difference Between Proposed AD and Referenced Service Information

Operators should note that, although the Accomplishment Instructions of the referenced service information describe procedures for reporting all cracks to Boeing, this proposed AD would not require that action.

Costs of Compliance

There are about 842 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 459 airplanes of U.S. registry. The proposed inspection would take about 110 work hours per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $4,039,200, or $8,800 per airplane, per inspection cycle.

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 proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 proposed 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 proposed 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, Safety.

   The Proposed Amendment

   Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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 Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):

   BOEING: Docket No. FAA-2007-28884; Directorate Identifier 2007-NM- 116-AD.

   Comments Due Date

   (a) The FAA must receive comments on this AD action by September 24, 2007.

   Affected ADs

   (b) None.

   Applicability

   (c) This AD applies to all Boeing Model 727, 727C, 727-100, 727- 100C, 727-200, and 727-200F series airplanes, certificated in any category.

   Unsafe Condition

   (d) This AD results from a report of cracks at multiple locations on certain areas of the crown skin. We are issuing this AD to detect and correct fatigue cracks of the crown skin, which could result in rapid decompression of 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.

   Repetitive Inspections and Repair

   (f) Before the accumulation of 66,000 total flight cycles, or within 3,500 flight cycles after the effective date of this AD, whichever occurs later, do an external high frequency eddy current inspection of the crown skin for cracks at stringer attachment holes between stringer 11L and stringer 11R and from body station (BS) 259.5 to BS 1183. Repair any crack found before further flight. Do the actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 727-53A0224, dated April 10, 2003, except as provided by paragraph (g) of this AD. Repeat the inspection at intervals not to exceed 3,500 flight cycles.

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

   Alternative Methods of Compliance (AMOCs)

   (h)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

   (2) To request a different method of compliance or a different compliance time

   [[Page 44435]]

   for this AD, follow the procedures in 14 CFR 39.19. 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.

   Issued in Renton, Washington, on July 30, 2007. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. E7-15426 Filed 8-7-07; 8:45 am]

   BILLING CODE 4910-13-P