[Federal Register Volume 70, Number 197 (Thursday, October 13, 2005)]
[Rules and Regulations]
[Pages 59644-59647]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-20264]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20137; Directorate Identifier 2004-NM-96-AD; 
Amendment 39-14338; AD 2005-20-41]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 757-200, -200PF, and -300 
Series Airplanes, Powered by Pratt & Whitney PW2000 Series Engines

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

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Boeing Model 757-200, -200PF, and -300 series airplanes, 
powered by Pratt & Whitney PW2000 series engines. This AD requires 
repetitive inspections for loose or damaged components of the support 
brackets and associated fasteners for the hydraulic lines located in 
the nacelle struts, and any related investigative and corrective 
actions. This AD results from reports of damage and subsequent failure 
of the support brackets and associated fasteners for the hydraulic 
lines located internal to the upper fairing cavity of the nacelle 
struts. We are issuing this AD to prevent such failure, which, in 
conjunction with sparking of electrical wires, failure of seals that 
would allow flammable fluids to migrate to compartments with ignition 
sources, or overheating of the pneumatic ducts beyond auto-ignition 
temperatures, could result in an uncontained fire.

DATES: This AD becomes effective November 17, 2005.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of November 17, 
2005.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., Nassif Building, 
Room PL-401, Washington, DC.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT: Tom Thorson, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 917-6508; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the AD docket 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 (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section. This 
docket number is FAA-2005-20137; the directorate identifier for this 
docket is 2004-NM-96-AD.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain Boeing Model 
757 series airplanes. That NPRM was published in the Federal Register 
on January 28, 2005 (70 FR 4052). That NPRM proposed to require 
repetitive inspections for loose or damaged components of the support 
brackets and associated fasteners for the hydraulic lines located in 
the nacelle struts, and any related investigative and corrective 
actions.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments on the NPRM 
that have been received.

Support for Proposed AD

    Two commenters concur with the proposed AD as written.

Requests To Extend Compliance Time

    Two commenters ask that the compliance time for the initial and 
repetitive inspections specified in the proposed AD be extended.
    One commenter asks that the compliance time for the initial and 
repetitive inspections be extended to 6,000 flight hours or 24 months, 
whichever is first. The proposed AD specifies initial and repetitive 
inspections at intervals not to exceed 6,000 flight hours or 18 months. 
The commenter adds that, based on access, labor hour requirements, and 
the nature of the detailed inspections, this type of work aligns with 
the airline's heavy maintenance program, which is calendar-based and 
FAA-approved at 24-month intervals. The commenter states that, because 
the proposed inspections are fatigue-related, an equivalent level of 
safety is maintained by extending the proposed calendar compliance 
time.
    A second commenter asks that the compliance time for the repetitive 
inspections be changed to 7,500 flight hours or 24 months. The 
commenter states that the proposed AD requires the initial inspection 
to be accomplished within 18 months or 6,000 flight hours, regardless 
of total flight cycles/hours on the airplane. The commenter adds that 
the safety concern addressed by the proposed AD appears to be age-
related. Additionally, consideration should be given to whether or not, 
and when, the work described in Boeing Service Bulletin 757-29-0043, 
dated June 21, 1990 (the concurrent service bulletin referenced in the 
proposed AD) was accomplished. The commenter also states that the 
initial and repetitive inspection interval in the proposed AD coincides 
with the published Material Review Board's most conservative periodic 
check (PCK) interval; several operators, including the commenter, have 
escalated that PCK interval to 24 months. The commenter concludes that 
attempting to accomplish the proposed actions within the proposed 
compliance time would be expensive; extending the compliance time would 
allow operators who have escalated the PCK interval to accomplish the 
inspections during maintenance checks.
    We agree to extend the compliance time for the initial and 
repetitive inspections to 6,000 flight hours or 24 months, whichever is 
first. The fatigue-related failures are a function of airplane flight 
hours and flight cycles, not a direct function of calendar time. 
Extending the compliance time will continue to provide an equivalent 
level of safety, as noted by the commenter. However, we do not agree to 
extend the compliance time to 7,500 flight hours or 24 months; the 
6,000-flight-hour compliance time was based on service history of part 
failures and an engineering fatigue analysis by the original equipment 
manufacturer (OEM). We have changed paragraph (f) of this AD to reflect 
the revised compliance time.

Request To Change Costs of Compliance Section

    Two commenters ask for changes to the Costs of Compliance section.
    One commenter states that the estimate in the cost section in the 
proposed AD specifies that it would

[[Page 59645]]

take 35 work hours to accomplish the inspection required by paragraph 
(f) of the proposed AD, but the commenter estimates that it would take 
47 work hours to accomplish that inspection. The commenter adds that 
the proposed AD also requires accomplishing the concurrent actions 
specified in paragraph (g) of the proposed AD and referenced in Boeing 
Service Bulletin 757-29-0043, dated June 21, 1990; however, the cost 
for those actions is not included in the Costs of Compliance section. 
The commenter concludes that the cost for the inspections was 
underestimated and the cost for the concurrent actions was omitted.
    A second commenter asks that we change the Costs of Compliance 
section in the proposed AD to specify that the number of work hours 
necessary to accomplish the proposed inspection and the concurrent 
actions would be determined by operators on a case-by-case basis.
    We do not agree to change the work hours in this AD or specify that 
operators will determine the number of work hours necessary for 
accomplishing the actions. The number of work hours represent the time 
necessary to perform only the actions actually required by the AD. The 
actions in an AD normally reflect only the costs of the specific 
required action (inspection) based on the best data available from the 
manufacturer; however, this AD also includes the time required to gain 
access and close up. The cost analysis in AD rulemaking actions 
typically does not include incidental costs such as the time necessary 
for planning, or time necessitated by other administrative actions. 
Those incidental costs, which may vary significantly among operators, 
are almost impossible to calculate. We have made no change to the AD in 
this regard.
    We do agree to add the cost for the concurrent actions since those 
actions were inadvertently omitted from the NPRM. We have added a new 
paragraph to the Costs of Compliance section which estimates the work 
hours and cost per airplane for accomplishing the concurrent actions.

Request To Change Statement of Unsafe Condition

    One commenter, the OEM, asks that we change the statement of unsafe 
condition specified in the proposed AD. The statement of unsafe 
condition is as follows: ``We are proposing this AD to prevent 
flammable fluids from leaking into the interior compartment of the 
nacelle struts where ignition sources exist, which could result in the 
ignition of flammable fluids and an uncontained fire.'' The commenter 
states that the damage to the Pratt & Whitney strut has not caused any 
damage to barriers between the upper strut compartment and any other 
compartment; the hydraulic tube is clamped to frames, not to a vapor 
barrier. The commenter adds that the upper strut compartment is 
designated as a flammable leakage zone, and therefore, to the greatest 
extent possible, all ignition sources have been eliminated. The 
commenter notes that the unsafe condition addressed by the referenced 
service information does not result in any zone barriers being damaged. 
The commenter concludes that any leakage of flammable fluids will not 
come in contact with ignition sources; additionally, the upper strut 
compartment has drainage provisions to prevent the accumulation of 
flammable fluids.
    We agree to change the description of the unsafe condition. The 
commenter is accurate in the statement that any leakage of flammable 
fluids will not come in contact with ignition sources because the upper 
strut compartment has drainage provisions to prevent the accumulation 
of flammable fluids. Due to the design of the system installations in 
the strut compartments, an additional failure would have to occur to 
result in the ignition of flammable fluids. Additional failures include 
shorting and sparking of electrical wires in either the strut upper 
fairing cavity or torque box, failure of seals that would allow 
flammable fluids to migrate to compartments with ignition sources, or 
overheating of the pneumatic ducts beyond auto-ignition temperatures. 
The description of the unsafe condition has been changed throughout the 
AD.

Request To Clarify Acceptable Part Numbers

    One commenter states that the proposed AD requires accomplishing 
the actions specified in two different service bulletins, which are 
referenced in paragraphs (f) and (g) of the proposed AD. The commenter 
is concerned because the part numbers specified in those two bulletins 
are different. The commenter recommends that the proposed AD be revised 
to specify that the part numbers listed in either service bulletin are 
acceptable configurations and fully comply with the actions specified 
in the proposed AD.
    We acknowledge and provide clarification for the commenter's 
concern. The OEM verified with us that the different part numbers 
specified in the referenced service bulletins are due to one series of 
parts having pilot holes and the other series not having pilot holes. 
Therefore, the part numbers identified in either service bulletin are 
acceptable configurations and fully comply with the AD requirements for 
the modifications. We have added a note to the AD for clarification. In 
addition, once a revision to the service bulletins has been issued by 
the manufacturer, and reviewed and accepted by us, we will approve the 
use of either series of part numbers as an acceptable alternative 
method of compliance (AMOC) according to paragraph (j) of this AD.

Request To Clarify the Repair Approval Specified in Paragraph (i)

    One commenter asks that paragraph (i) of the proposed AD, titled 
``Repair Information,'' be clarified concerning the requirement to 
obtain repair approval per the Manager, Seattle Aircraft Certification 
Office (ACO). The commenter questions if this approval is required for 
all Boeing-assisted repairs to the engine strut frames, or if the 
approval is only required for Boeing-assisted repairs found during the 
inspections required by the proposed AD.
    We interpret the commenter's question to be whether damage found 
inside the strut that is not found during the inspection required by 
the AD requires Seattle ACO approval of the repair method. Our response 
is that only repairs of hardware damage found during the inspection 
required by the AD for which the service bulletin specifies a Boeing-
assisted repair per the referenced service information need be 
submitted to the Seattle ACO for approval. If specific cases develop 
and the repair method is not apparent to the operator, contact the 
Seattle ACO for guidance. We have not changed the AD in this regard.

Request To Resolve Parts Issues

    One commenter states that the following parts issues represent an 
undue burden on operators by needlessly restricting operator action, 
and asks that these issues be resolved. Those issues and our responses 
are as follows:
    1. The commenter asks that the proposed AD be changed to allow 
dimensional drawings or provisions for operators to fabricate 
acceptable substitute brackets. The commenter states that, since parts 
are not available from the OEM, operators must fabricate the brackets 
and re-use the fasteners and rubber blocks, as necessary.
    We do not agree that operators can be allowed to fabricate their 
own parts. Operators would be required to fabricate parts by using an 
approved design, and we cannot authorize this without

[[Page 59646]]

reviewing the operators' design data. The manufacturer has indicated 
that the parts required are readily available; therefore, obtaining 
them should not be a problem. However, should parts not be available in 
a timely manner, operators may provide the design data to us and 
request approval of an AMOC per paragraph (j) of this AD.
    2. The commenter asks that we revise Section II of Boeing Service 
Bulletin 757-29-0064 (referenced in the proposed AD as the appropriate 
source of service information for accomplishing the inspections for 
Model 757-200 and -200PF series airplanes) to add a provision for 
providing brackets and hardware for all stations. The commenter states 
that Section II of the service bulletin contains material information 
that is inadequate. The commenter has found that only parts necessary 
for station 149.5 are included in that section; however, the service 
bulletin specifies inspecting and replacing parts at stations 102.1, 
128.0, 149.5, 161.35, and 180.0 on the left and right sides of the 
airplane. In addition, the commenter found damaged/worn parts at other 
stations.
    3. The commenter asks that we require brackets and hardware to be 
stocked and provided by Boeing until terminating action is developed. 
The commenter states that parts for all stations are not readily 
available from the OEM or other suppliers.
    We do not agree to advise Boeing to revise Section II of the 
referenced service bulletin, or to require that Boeing provide parts 
until terminating action is developed. The technical content of the 
referenced service bulletin is correct and contains adequate 
information and procedures to accomplish the repetitive inspections. 
Therefore, we have determined that it is not necessary for the 
manufacturer to revise the service bulletin before issuance of this AD. 
In addition, we have no regulatory basis to require the type 
certificate holder to provide the parts necessary to comply with the 
corrective action specified in the AD. The manufacturer has indicated 
that the parts required are readily available; therefore, obtaining 
them should not be a problem. However, under the provisions of 
paragraph (j) of this AD, affected operators may request approval of an 
AMOC.

Request To Approve Future Service Information

    One commenter, the OEM, asks that the appropriate sections in the 
proposed AD be changed to reference Revision 1 of Boeing Service 
Bulletins 757-29-0064 and 757-29-0065. (Boeing Service Bulletins 757-
29-0064 and 757-29-0065, both dated February 29, 2004, are referenced 
in the NPRM as the appropriate sources of service information for 
accomplishing the repetitive inspections.) The commenter states that 
those service bulletins are currently being revised and are expected to 
be released soon.
    We cannot accept as-yet unpublished service documents for 
compliance with the requirements of an AD. Referring to an unavailable 
service bulletin in an AD violates Office of the Federal Register 
regulations for approving materials that are incorporated by reference. 
We have not changed the AD regarding this issue because the service 
bulletins have not been revised and we cannot delay the final rule to 
wait for revisions to be issued. However, under the provisions of 
paragraph (j) of this AD, affected operators may request approval to 
use a later revision of the referenced service bulletin as an AMOC.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

    We have changed this AD to clarify the appropriate procedure for 
notifying the principal inspector before using any approved AMOC on any 
airplane to which the AMOC applies.

Conclusion

    We have carefully reviewed the available data, including the 
comments that we received, and determined that air safety and the 
public interest require adopting the AD with the changes described 
previously. These changes will neither increase the economic burden on 
any operator nor increase the scope of the AD.

Costs of Compliance

    This AD affects about 432 airplanes worldwide and 377 airplanes of 
U.S. registry.
    The inspection/test takes about 35 work hours per airplane 
(including access and close-up), at an average labor rate of $65 per 
work hour. Based on these figures, the estimated cost of the 
inspection/test for U.S. operators is $857,675, or $2,275 per airplane, 
per inspection/test cycle.
    The concurrent actions would take about 38 work hours per airplane, 
at an average labor rate of $65 per work hour. Required parts cost is 
minimal. Based on these figures, the estimated cost of the concurrent 
actions is $2,470 per airplane.

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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under 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

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The Federal Aviation Administration (FAA) amends Sec.  39.13

[[Page 59647]]

by adding the following new airworthiness directive (AD):

2005-20-41 Boeing: Amendment 39-14338. Docket No. FAA-2005-20137; 
Directorate Identifier 2004-NM-96-AD.

Effective Date

    (a) This AD becomes effective November 17, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 757-200, -200PF, and -300 
series airplanes; certificated in any category; powered by Pratt & 
Whitney PW2000 series engines.

Unsafe Condition

    (d) This AD was prompted by reports of damage and subsequent 
failure of the support brackets and associated fasteners for the 
hydraulic lines located internal to the upper fairing cavity of the 
nacelle struts. We are issuing this AD to prevent such failure, 
which, in conjunction with sparking of electrical wires, failure of 
seals that would allow flammable fluids to migrate to compartments 
with ignition sources, or overheating of the pneumatic ducts beyond 
auto-ignition temperatures, could result in an uncontained fire.

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

    (f) Within 6,000 flight hours or 24 months after the effective 
date of this AD, whichever is first: Do a detailed inspection for 
loose or damaged components of the support brackets and associated 
fasteners for the hydraulic lines located in the nacelle struts by 
accomplishing all of the actions specified in Part 1, Part 2, and 
Part 3 of the Accomplishment Instructions of Boeing Service Bulletin 
757-29-0064 (for Model 757-200 and -200PF series airplanes) or 
Boeing Service Bulletin 757-29-0065 (for Model 757-300 series 
airplanes), both dated February 29, 2004; as applicable. Repeat the 
inspection thereafter at intervals not to exceed 6,000 flight hours 
or 24 months, whichever is first.


    Note 1: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc., may be used. Surface cleaning and elaborate 
access procedures may be required.''

Concurrent Service Bulletin

    (g) Prior to or concurrently with the accomplishment of 
paragraph (f) of this AD: Accomplish all of the actions specified in 
the Accomplishment Instructions of Boeing Service Bulletin 757-29-
0043, dated June 21, 1990.

    Note 2: The part numbers identified in Boeing Service Bulletins 
757-29-0064 or 757-29-0065, both dated February 29, 2004; or Boeing 
Service Bulletin 757-29-0043, dated June 21, 1990; are acceptable 
configurations and fully comply with the AD requirements for the 
actions required by paragraphs (f) and (g) of this AD.

Related Investigative and Corrective Actions

    (h) Except as required by paragraph (i) of this AD: If any loose 
or damaged part is found during any inspection required by paragraph 
(f) of this AD, before further flight, do all of the related 
investigative and corrective actions specified in Part 1 and Part 2 
of the Accomplishment Instructions of Boeing Service Bulletin 757-
29-0064, or Boeing Service Bulletin 757-29-0065, both dated February 
29, 2004; as applicable.

Repair Information

    (i) If any damage is found during any inspection required by 
this AD, and the service bulletin specifies contacting Boeing for 
appropriate action: Before further flight, repair per a method 
approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA. For a repair method to be approved, the approval letter 
must specifically refer to this AD.


    Note 3: There is no terminating action currently available for 
the repetitive inspections required by paragraph (f) of this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle ACO, 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 Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Material Incorporated by Reference

    (k) You must use Boeing Service Bulletin 757-29-0064, dated 
February 29, 2004, or Boeing Service Bulletin 757-29-0065, dated 
February 29, 2004; and Boeing Service Bulletin 757-29-0043, dated 
June 21, 1990; as applicable, 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 
these documents in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, 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 
(202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on September 30, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-20264 Filed 10-12-05; 8:45 am]
BILLING CODE 4910-13-P