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Proposed Rule

Airworthiness Directives; Boeing Model 757 and 767 Series Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 757 and 767 series airplanes. This proposal would require inspection to determine the serial number of the hydraulic pump in the ram air turbine (RAT), and corrective action, if necessary. This action is necessary to prevent a cracked hanger arm of the hydraulic pump of the RAT that can fracture under load and lead to failure of the RAT to provide hydraulic power to the primary flight control system during an emergency when both engines have failed. Loss of hydraulic power to the primary flight controls could result in loss of control of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by March 22, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-83-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-83-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplanes, PO Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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FOR FURTHER INFORMATION CONTACT:

Kenneth Frey, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6468; fax (425) 917-6590.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

  • Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
  • For each issue, state what specific change to the proposed AD is being requested.
  • Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Start Printed Page 5786Docket Number 2003-NM-83-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-83-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received a report indicating that some ram air turbines (RAT) may have hydraulic pumps with cracked hanger arms on certain Boeing Model 757 and 767 series airplanes. The supplier of the RATs identified a departure from the defined manufacturing process as the cause for production of hanger arms with potential surface cracks, which affects approximately 154 hydraulic pumps with certain serial numbers. A cracked hanger arm of the hydraulic pump of the RAT, if not corrected, can fracture under load and lead to failure of the RAT to provide hydraulic power to the primary flight control system during an emergency when both engines have failed. Loss of hydraulic power to the primary flight controls could result in loss of control of the airplane.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Special Attention Service Bulletin 757-29-0060, dated September 12, 2002 (for Model 757-200, -200CB, and -200PF series airplanes); Boeing Special Attention Service Bulletin 757-29-0061, dated September 12, 2002 (for Model 757-300 series airplanes); Boeing Special Attention Service Bulletin 767-29-0103, dated September 12, 2002 (for Model 767-200, -300, and -300F series airplanes); and Boeing Special Attention Service Bulletin 767-29-0106, dated September 12, 2002 (for Model 767-400ER series airplanes).

These service bulletins describe procedures for inspection to determine the serial number of the hydraulic pump in the RAT, and corrective action, if necessary. The corrective action(s) includes either replacing the hydraulic pump with a serviceable hydraulic pump that is outside the range of the affected serial numbers, or reworking and reidentifying the existing hydraulic pump. Accomplishment of the actions specified in the service bulletins is intended to adequately address the identified unsafe condition.

These service bulletins also refer to Parker Service Bulletin 6513902-29-305, dated November 30, 2001, as an additional source of service information for the list of affected hydraulic pump serial numbers and for accomplishment of the reworking and reidentifying of the existing hydraulic pump for Model 757 and 767 series airplanes.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the Boeing service bulletins described previously.

Cost Impact

There are approximately 1,851 airplanes of the affected design in the worldwide fleet. The FAA estimates that 1,038 airplanes of U.S. registry would be affected by this proposed AD.

We estimate that it would take approximately 1 work hour per airplane to accomplish the proposed inspection, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed inspection on U.S. operators is estimated to be $67,470, or $65 per airplane.

We also estimate that it would take approximately 4 work hours per airplane (affecting approximately 154 airplanes) to accomplish the proposed replacement of the hydraulic pump, if required, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed replacement on U.S. operators is estimated to be $260 per airplane.

We also estimate that it would take approximately 5 work hours per airplane (affecting approximately 154 airplanes) to accomplish the proposed reworking and reidentification of the hydraulic pump, if required, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed reworking and reidentification on U.S. operators is estimated to be $325 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions. The manufacturer may cover the cost of replacement parts associated with this proposed AD, subject to warranty conditions. As a result, the costs attributable to the proposed AD may be less than stated above.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

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PART 39—AIRWORTHINESS DIRECTIVES

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

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

End Authority
[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Boeing: Docket 2003-NM-83-AD.

Applicability: Model 757-200, -200CB, -200PF, and -300 series airplanes, line numbers 1 through 998 inclusive; and Model 767-200, -300, -300F, and -400ER series airplanes, line numbers 1 through 869 inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent a cracked hanger arm of the hydraulic pump of the ram air turbine (RAT) Start Printed Page 5787that can fracture under load and lead to failure of the RAT to provide hydraulic power to the primary flight control system during an emergency when both engines have failed, which could result in loss of hydraulic power to the primary flight controls and consequent loss of control of the airplane; accomplish the following:

Service Bulletin Reference

(a) The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of the following service bulletins in Table 1 of this AD, as applicable:

Table 1.—Service Bulletins

MoldedService bulletinDate
Model 757-200, -200CB, and -200PF series airplanesBoeing Special Attention Service Bulletin 757-29-0060September 12, 2002.
Model 757-300 series airplanesBoeing Special Attention Service Bulletin 757-29-0061September 12, 2002.
Model 767-200, -300, and -300F series airplanesBoeing Special Attention Service Bulletin 767-29-0103September 12, 2002.
Model 767-400ER series airplanesBoeing Special Attention Service Bulletin 767-29-0106September 12, 2002.

Note 1:

These service bulletins refer to Parker Service Bulletin 6513902-29-305, dated November 30, 2001, as an additional source of service information for the list of affected hydraulic pump serial numbers and for accomplishment of the reworking and reidentifying of the existing hydraulic pump for Model 757 and 767 series airplanes.

Inspection of Serial Number

(b) Within 36 months after the effective date of this AD, do an inspection to determine the serial number of the hydraulic pump in the RAT, per the service bulletin.

Corrective Actions

(c) If the hydraulic pump is found to have an affected serial number during the inspection required by paragraph (b) of this AD, within 36 months after the effective date of this AD, do the corrective action(s) in either paragraph (c)(1) or (c)(2) of this AD.

(1) Replace the hydraulic pump with a serviceable hydraulic pump that is outside the range of the affected serial numbers, per the service bulletin.

(2) Rework and reidentify the hydraulic pump, per the service bulletin.

Part Installation

(d) As of the effective date of this AD, no person shall install on any airplane a RAT hydraulic pump, Parker part number (P/N) 65139-02 or Hamilton Sunstrand P/N 5903420, with an affected serial number as listed in Parker Service Bulletin 6513902-29-305, dated November 30, 2001, unless it has been modified per paragraph (c)(2) of this AD.

Alternative Methods of Compliance

(e) In accordance with 14 CFR 39.19, the Manager, Seattle Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance for this AD.

Start Signature

Issued in Renton, Washington, on January 29, 2004.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 04-2479 Filed 2-5-04; 8:45 am]

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