Document ID: FAA-2008-0295-0010
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; Boeing Model 757 Airplanes
Posted Date: 2009-10-19T04:00Z

[Federal Register: October 19, 2009 (Volume 74, Number 200)]
[Proposed Rules]               
[Page 53430-53433]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19oc09-19]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0295; Directorate Identifier 2007-NM-298-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 757 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for all Boeing Model 757-200, -200PF, -200CB, and -300 series 
airplanes. The original NPRM would have required an inspection of the 
two spring arms in the spin brake assemblies in the nose wheel well to 
determine if the spring arms are made of aluminum or composite 
material, and repetitive related investigative/corrective actions if 
necessary. The original NPRM resulted from reports of cracked and 
broken aluminum springs. This action revises the original NPRM to 
include a parts installation paragraph and to provide options for 
terminating the repetitive actions. We are proposing this supplemental 
NPRM to detect and correct cracked or broken springs. A cracked or 
broken spring could separate from the airplane and result in potential 
hazard to persons or property on the ground, or ingestion into the 
engine with engine damage and potential shutdown, or damage to the 
airplane.

DATES: We must receive comments on this supplemental NPRM by November 
13, 2009.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     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.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1, fax 206-766-5680; e-mail me.boecom@boeing.com; 
Internet https://www.myboeingfleet.com. You may review copies of the 
referenced service information at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information 
on the availability of this material at the FAA, call 425-227-1221 or 
425-227-1152.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Chris Hartman, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
917-6432; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0295; 
Directorate Identifier 2007-NM-298-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued a notice of proposed rulemaking (NPRM) (the ``original 
NPRM'') to amend 14 CFR part 39 to include an airworthiness directive 
(AD) that would apply to all Boeing Model 757-200, -200PF, -200CB, and 
-300 series airplanes. That original NPRM was published in the Federal 
Register on March 13, 2008 (73 FR 13492). That original NPRM proposed 
to require an inspection of the two spring arms in the spin brake 
assemblies in the nose wheel well to determine if the spring arms are 
made of aluminum or composite material, and repetitive related 
investigative/corrective actions if necessary.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received from the seven commenters.

Request To Refer to Revision 1 of the Service Bulletin

    Boeing and Air Transport Association (ATA), on behalf of its member 
American Airlines (AAL), request that we include Revision 1 of Boeing 
Special Attention Service Bulletin 757-32-0176, dated October 16, 2008, 
in the AD. (We referred to the original issue, Boeing Special Attention 
Service Bulletin 757-32-0176, dated September 10, 2007, as the 
appropriate source of service information in the original NPRM.) Boeing 
points out that the

[[Page 53431]]

revision will include a preferred alternative replacement part made 
from corrosion-resistant steel (CRES), as well as the current options 
allowed in the original issue of the service bulletin. The commenters 
state that including Revision 1 of the service bulletin in the AD would 
eliminate the need for additional rulemaking.
    We agree with the request to include Boeing Special Attention 
Service Bulletin 757-32-0176, Revision 1, dated October 16, 2008, as 
the appropriate source of service information in this supplemental 
NPRM. Other changes in Revision 1 include changes throughout the 
service bulletin to include references to the alternative replacement 
part, and other editorial changes such as ``springs'' (instead of 
``spin brake spring arms'') and ``Toe Piece'' (instead of ``Toe 
Plate''). Revision 1 of the service bulletin also includes a new Figure 
7, which includes steps for assembling the new spin brake assembly with 
a composite ring. We have therefore revised all applicable sections in 
this AD to refer to ``springs'' instead of ``spring arms'' to match the 
description in Revision 1 of the service bulletin.
    We have also revised paragraph (f) of the original NPRM (paragraph 
(g) of this supplemental NPRM) to refer to Revision 1 of the service 
bulletin. Additionally, we have added a new paragraph (i) to this 
supplemental NPRM to specify that replacement of an aluminum spin brake 
assembly with a spin brake assembly made of CRES is an optional 
terminating action for the repetitive inspections specified in 
paragraph (g) of this supplemental NPRM for that spring. In addition, 
we have included a new paragraph (k) in this supplemental NPRM to give 
credit to operators who have accomplished the actions in accordance 
with Boeing Special Attention Service Bulletin 757-32-0176, dated 
September 10, 2007.

Request To Address Interchangeability of Parts

    ATA, on behalf of its member Delta Airlines (DAL), requests that we 
address the interchangeability of spring arms. DAL states that the 
original NPRM implies the inspection to determine the type of spring 
arm is done once in the lifetime of the airplane. DAL further states 
that aluminum spring arms and composite spring arms are 
interchangeable; therefore, the spring arm could be changed from one to 
the other type at any time in the life of an airplane. DAL contends 
that repetitive inspections to determine the type of spring arm should 
be required for all airplanes unless it can be proven that aluminum 
brake arms are not installed and never will be.
    We agree that the issue of interchangeability of spring arms needs 
to be clarified, although we disagree with the request to add a 
repetitive inspection to determine the type of spring arm. We have, 
instead, added a new paragraph (j) to this supplemental NPRM to specify 
that, as of the effective date of the proposed AD, no person may 
install an aluminum spring arm on any airplane unless it has been 
inspected and all applicable related investigative and corrective 
actions have been applied in accordance with the requirements of 
paragraph (g) of this supplemental NPRM.

Request To Allow Alternative Procedure

    Northwest Airlines (NWA), and ATA on behalf of its member DAL, 
request that we allow replacement of the brake arm in accordance with 
the Boeing 757 Airplane Maintenance Manual (AMM) 32-45-05, Nose wheel 
spin brake--maintenance practices. NWA states that these procedures 
have been in place for a long time and are equivalent to the procedures 
for the replacement specified in Boeing Special Attention Service 
Bulletin 757-32-0176, dated September 10, 2007. The commenters assert 
that including a note stating that the AMM is acceptable as an 
alternative procedure would alleviate compliance concerns if the 
replacement was or is done in accordance with the AMM procedures, but 
not concurrently with the inspection proposed in the original NPRM.
    We agree with the commenters that the procedures in the service 
bulletin and in the AMM are equivalent. However, Part 5 of Boeing 
Special Attention Service Bulletin 757-32-0176, Revision 1, dated 
October 16, 2008, already refers to the AMM procedures; therefore, it 
is not necessary for us to revise the supplemental NPRM to include a 
reference to the AMM. We have not changed this supplemental NPRM in 
this regard.

Requests To Clarify Compliance Times

    ATA, on behalf of its member AAL, requests that we revise the NPRM 
to clarify the compliance times. AAL explains that the original NPRM 
refers to paragraph 1.E., ``Compliance,'' of Boeing Special Attention 
Service Bulletin 757-32-0176, dated September 10, 2007, as the source 
for compliance times. However, AAL notes that the table in paragraph 
1.E. guides operators to perform the actions in accordance with Parts 
2, 3, and 4 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 757-32-0176, dated September 10, 2007. Part 
2 includes a note that states that Parts 3 and 4 ``must be done'' at 
the same time as Part 2 where aluminum spin break arms are installed; 
AAL states that this note is incorrect.
    We agree with the commenter that Parts 2, 3, and 4 of the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 757-32-0176, dated September 10, 2007, do not need to be done 
simultaneously. Boeing Special Attention Service Bulletin 757-32-0176, 
Revision 1, dated October 16, 2008, revised Part 2 to specify that 
Parts 3 and 4 ``can be done'' at the same time. The compliance times in 
paragraph 1.E., ``Compliance,'' are correct; therefore, we have not 
changed the supplemental NPRM in this regard.

Request To Clarify Part 1 and Part 6 Compliance

    ATA, on behalf of DAL, requests that we address providing for 
access and close-up at times convenient to the operators' maintenance 
schedules. DAL notes that Parts 1 and 6 of the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 757-32-0176, 
dated September 10, 2007, spell out access and close-up requirements. 
DAL states that operators might wish to combine the inspection proposed 
in the original NPRM with other maintenance visits where access is 
already available. DAL states that tracking compliance for access and 
close-up tasks using the procedures specified in the original NPRM 
would add paperwork without value. DAL requests that we add a note to 
the supplemental NPRM that states that Parts 1 and 6 of the 
Accomplishment Instructions are for operator use and that compliance 
documentation is not required.
    We disagree with the request to change this supplemental NPRM to 
state that Parts 1 and 6 of the Accomplishment Instructions of Boeing 
Special Attention Service Bulletin 757-32-0176, dated September 10, 
2007, are for operator use only. Both Note 7 under paragraph 3.A. of 
Boeing Special Attention Service Bulletin 757-32-0176, dated September 
10, 2007, and Note 8 under paragraph 3.A. of Boeing Special Attention 
Service Bulletin 757-32-0176, Revision 1, dated October 16, 2008, give 
provisions for operators to use other accepted alternative procedures 
for actions specified in the Accomplishment Instructions when the words 
``refer to'' are used. Those words are used in both Parts 1 and 6 of 
the Accomplishment Instructions. In addition, although these actions 
are

[[Page 53432]]

necessary to accomplish the inspections, Boeing Special Attention 
Service Bulletin 757-32-0176, Revision 1, dated October 16, 2008, 
provides alternative methods for access and close-up, as defined in 
Notes 5 and 6 under paragraph 3.A. of the Accomplishment Instructions. 
Since the suggested note is already contained in the Accomplishment 
Instructions of the service bulletin, no additional notes are necessary 
in this supplemental NPRM. We have not changed this supplemental NPRM 
in either regard.

Request To Address Ferry Permits

    ATA, on behalf of DAL, requests that we state that since removal of 
the brake arms is allowed by the Minimum Equipment List (MEL), no ferry 
permit information is included in this supplemental NPRM. The commenter 
points out that many ADs include language regarding ferry flights.
    We disagree with the request to address ferry permits (also called 
``special flight permits'') in this supplemental NPRM. As specified in 
the ``Relevant Service Information'' section of the original NPRM, 
Boeing Special Attention Service Bulletin 757-32-0176, dated September 
10, 2007, states that the airplane can be operated for 10 calendar days 
with the spin brake spring arms removed provided the airplane is 
operated within the restrictions given in the Boeing 757 Master Minimum 
Equipment List (MMEL). If necessary, special flight permits, and the 
process for applying for them, are described in Section 21.197 and 
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 
21.199); it is not necessary to change this supplemental NPRM in this 
regard.

Request To Revise Cost Estimate

    Continental Airlines (CAL) believes that the cost estimate given in 
the original NPRM is relatively low as it assumes zero fallout. If CAL 
decides either to accomplish the recommended terminating action (which 
would be to install a CRES spring arm) due to a crack or to avoid the 
repetitive inspections, it will not only cost around $10,000 for parts 
and labor per spring arm, but will add weight to the airplane, making 
for additional yearly fuel costs.
    We infer that CAL would like us to revise the ``Costs of 
Compliance'' section of the original NPRM. We disagree. We recognize 
that, in doing the actions required by an AD, operators might incur 
incidental costs in addition to the direct costs. The cost analysis in 
AD rulemaking actions, however, typically does not include the cost of 
optional actions, although we recognize that doing the optional 
terminating action imposes additional operational costs. We have not 
changed this supplemental NPRM in this regard.

Requests To Clarify Inspections

    NWA and CAL request that we clarify the inspections. CAL believes 
that the visual and high-frequency eddy current (HFEC) inspections are 
redundant and give somewhat contradictory information about the failure 
mode of the spring arm. CAL recommends that Boeing and the FAA review 
the inspection intervals again before the next revision of the service 
bulletin. NWA finds it unusual that Boeing Special Attention Service 
Bulletin 757-32-0176, dated September 10, 2007, has two separate and 
parallel inspection programs to look for cracking in the subject spring 
arms. One inspection program is a 300-cycle repetitive general visual 
inspection and the other is a 1,500-cycle repetitive HFEC inspection. 
NWA asks the FAA to work with Boeing to clarify that these inspections 
are either parallel to or optional to each other.
    We disagree that the inspections are redundant. The manufacturer 
has determined that both inspections are needed for the required Damage 
Tolerance Rating (DTR). The manufacturer states that analytical crack 
growth and residual strength do not match the cracking found in 
service, and that there are several variables that can affect the 
stress in the part. The HFEC inspection is the minimum required at the 
longer 1,500-flight-cycle intervals, while the general visual 
inspection provides added safety for cracking at 300 flight cycle 
intervals. Therefore, both the general visual and the HFEC inspections 
are necessary to meet the DTR. We have not changed this supplemental 
NPRM in this regard.

Request To Revise Repetitive Inspection Interval

    Air Astana requests that we consider the possibility of revising 
the repetitive interval from 1,500 flight cycles to 1,800 flight 
cycles. Air Astana points out that its fleet of Model 757-200 airplanes 
accumulates 1,800 flight cycles between C-checks.
    We disagree with the request to revise the repetitive inspection 
intervals. In developing an appropriate compliance time for this 
action, we considered the urgency associated with the subject unsafe 
condition and the practical aspect of accomplishing the required 
modification within a period of time that corresponds to the normal 
scheduled maintenance for most affected operators. These maintenance 
schedules can vary greatly from operator to operator. However, 
according to the provisions of paragraph (l) of this supplemental NPRM, 
we may approve a request to adjust the compliance time if the request 
includes data that prove that the new compliance time would provide an 
acceptable level of safety. We have not changed this supplemental NPRM 
in this regard.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

    We are proposing this supplemental NPRM because we evaluated all 
pertinent information and determined an unsafe condition exists and is 
likely to exist or develop on other products of the same type design. 
Certain changes described above expand the scope of the original NPRM. 
As a result, we have determined that it is necessary to reopen the 
comment period to provide additional opportunity for the public to 
comment on this supplemental NPRM.

Explanation of Additional Paragraph in the Supplemental NPRM

    We have added a new paragraph (d) to this supplemental NPRM to 
provide the Air Transport Association (ATA) of America code. This code 
is added to make this supplemental NPRM parallel with other new AD 
actions. We have reidentified subsequent paragraphs accordingly.

Costs of Compliance

    We estimate that this proposed AD would affect 668 airplanes of 
U.S. registry. We also estimate that it would take about 1 work-hour 
per product to comply with this proposed AD. The average labor rate is 
$80 per work-hour. Based on these figures, we estimate the cost of this 
proposed AD for U.S. operators to be $53,440, or $80 per product.

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

[[Page 53433]]

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 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 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. 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, 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 FAA amends Sec.  39.13 by adding the following new AD:

Boeing: Docket No. FAA-2008-0295; Directorate Identifier 2007-NM-
298-AD.

Comments Due Date

    (a) We must receive comments by November 13, 2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Boeing Model 757-200, -200PF, -200CB, 
and -300 series airplanes, certificated in any category.

Subject

    (d) Air Transport Association (ATA) of America Code 32: Landing 
Gear.

Unsafe Condition

    (e) This AD results from reports of cracked and broken aluminum 
springs. We are issuing this AD to detect and correct cracked or 
broken springs. A cracked or broken spring could separate from the 
airplane and result in potential hazard to persons or property on 
the ground, or ingestion into the engine with engine damage and 
potential shutdown, or damage to the airplane.

Compliance

    (f) Comply with this AD within the compliance times specified, 
unless already done.

Inspections and Corrective Actions

    (g) At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 757-32-
0176, Revision 1, dated October 16, 2008, except that where Boeing 
Special Attention Service Bulletin 757-32-0176, Revision 1, dated 
October 16, 2008, specifies a compliance time after the date ``on 
this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD: Do a 
general visual inspection to determine the material (aluminum or 
composite) of the two springs in the spin brake assemblies in the 
nose wheel well. A review of airplane maintenance records is 
acceptable in lieu of this inspection if the material can be 
conclusively determined from that review. Do all applicable related 
investigative and corrective actions, and all repetitive inspections 
thereafter, at the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 757-32-
0176, Revision 1, dated October 16, 2008. Do all actions in 
accordance with Boeing Special Attention Service Bulletin 757-32-
0176, Revision 1, dated October 16, 2008.

Optional Terminating Actions

    (h) Replacing an aluminum spin brake assembly with a spin brake 
assembly made of composite material in accordance with Figure 5 of 
Boeing Special Attention Service Bulletin 757-32-0176, Revision 1, 
dated October 16, 2008, ends the repetitive inspections required by 
paragraph (g) of this AD for that spring.
    (i) Replacing an aluminum spring with a spring made of 
corrosion-resistant steel (CRES), in accordance with Figure 6 of 
Boeing Special Attention Service Bulletin 757-32-0176, Revision 1, 
dated October 16, 2008, ends the repetitive inspections required by 
paragraph (g) of this AD for that spring.

Parts Installation

    (j) As of the effective date of this AD, no person may install 
an aluminum spring on any airplane unless it has been inspected and 
all applicable related investigative and corrective actions have 
been applied in accordance with the requirements of paragraph (g) of 
this AD.

Credit for Previous Revision of Service Bulletin

    (k) Actions done before the effective date of this AD in 
accordance with Boeing Special Attention Service Bulletin 757-32-
0176, dated September 10, 2007, are acceptable for compliance with 
the corresponding requirements of this AD.

Alternative Methods of Compliance (AMOCs)

    (l)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. Send information to 
Attn: Chris Hartman, Aerospace Engineer, Airframe Branch, ANM-120S, 
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., 
Renton, Washington 98057-3356; telephone (425) 917-6432; fax (425) 
917-6590. Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-
Requests@faa.gov.
    (2) To request a different method of compliance or a different 
compliance time 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 principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane.

    Issued in Renton, Washington, on October 5, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-24984 Filed 10-16-09; 8:45 am]

BILLING CODE 4910-13-P