[Federal Register Volume 69, Number 25 (Friday, February 6, 2004)]
[Proposed Rules]
[Pages 5785-5787]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-2479]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-83-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 757 and 767 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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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: 
<a href="/cdn-cgi/l/email-protection#9ea7b3fff0f3b3f0eeecf3fdf1f3f3fbf0eadef8ffffb0f9f1e8"><span class="__cf_email__" data-cfemail="bd8490dcd3d090d3cdcfd0ded2d0d0d8d3c9fddbdcdc93dad2cb">[email protected]</span></a>. 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.

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.

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:
    <bullet<ls-thn-eq> 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.
    <bullet<ls-thn-eq> For each issue, state what specific change to 
the proposed AD is being requested.
    <bullet<ls-thn-eq> 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

[[Page 5786]]

Docket 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

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:

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. 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. [FEDREG][VOL]*[/VOL][NO]*[/NO][DATE]*[/
DATE][PRORULES][PRORULE][PREAMB][AGENCY]*[/AGENCY][SUBJECT]*[/
SUBJECT][/PREAMB][SUPLINF][HED]*[/HED][EXTRACT][P]*[/P]
    To prevent a cracked hanger arm of the hydraulic pump of the ram 
air turbine (RAT)

[[Page 5787]]

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, 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
----------------------------------------------------------------------------------------------------------------
                  Molded                         Service bulletin                          Date
----------------------------------------------------------------------------------------------------------------
Model 757-200, -200CB, and -200PF series   Boeing Special Attention      September 12, 2002.
 airplanes.                                 Service Bulletin 757-29-
                                            0060.
Model 757-300 series airplanes...........  Boeing Special Attention      September 12, 2002.
                                            Service Bulletin 757-29-
                                            0061.
Model 767-200, -300, and -300F series      Boeing Special Attention      September 12, 2002.
 airplanes.                                 Service Bulletin 767-29-
                                            0103.
Model 767-400ER series airplanes.........  Boeing Special Attention      September 12, 2002.
                                            Service Bulletin 767-29-
                                            0106.
----------------------------------------------------------------------------------------------------------------


    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.

    Issued in Renton, Washington, on January 29, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-2479 Filed 2-5-04; 8:45 am]
BILLING CODE 4910-13-P


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