[Federal Register: July 30, 2007 (Volume 72, Number 145)]
[Rules and Regulations]
[Page 41438-41441]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30jy07-7]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-26441; Directorate Identifier 2006-NM-204-AD;
Amendment 39-15139; AD 2007-15-10]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747 Airplanes
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 all
Boeing Model 747 airplanes. This AD requires an inspection of the No. 2
and No. 3 windows on the left and right sides of the airplane to
determine their part numbers, and related investigative and corrective
actions if necessary. This AD results from loss of a No. 3 window in-
flight. We are issuing this AD to detect and correct cracking in the
fail-safe interlayer of certain No. 2 and No. 3 glass windows, which
could result in loss of the window and consequent rapid loss of cabin
pressure. Loss of the window could also result in crew communication
difficulties or incapacitation of the crew.
DATES: This AD becomes effective September 4, 2007.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of September 4,
2007.
ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov
or in person at the U.S. Department of Transportation,
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200
New Jersey Avenue, SE., 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: Steve Fox, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6425; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Examining the Docket
You may examine the airworthiness directive (AD) docket on the
Internet at http://dms.dot.gov or in person at the Docket Operations
office between 9 a.m.
[[Page 41439]]
and 5 p.m., Monday through Friday, except Federal holidays. The Docket
Operations office (telephone (800) 647-5527) is located on the ground
floor of the West Building at the street address stated in the
ADDRESSES section.
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to include an AD that would apply to all Boeing Model 747
airplanes. That NPRM was published in the Federal Register on December
8, 2006 (71 FR 71099). That NPRM proposed to require an inspection of
the No. 2 and No. 3 windows on the left and right sides of the airplane
to determine their part numbers, and related investigative and
corrective actions if necessary.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Support for the NPRM
Boeing supports the NPRM, and British Airways supports the intent
of the NPRM.
Request To Extend Grace Period
Qantas Airways states that the compliance times given in calendar
time (units of years) in Tables 1, 2, and 3 of Boeing Alert Service
Bulletin 747-56A2012, dated August 24, 2006, are not relevant for
windows installed after the issue date of the service bulletin. As an
example, the commenter states that a window installed on an airplane 5
years from now will have already surpassed the compliance time at the
time of installation. Qantas Airways, therefore, requests that the
calendar times in Tables 1, 2, and 3 of the service bulletin be revised
as follows: ``Within 2 (or 3) years after the date on this service
bulletin, or after the window was installed, whichever occurs last.''
Qantas Airways asserts that this change will ensure that the inspection
of newly installed windows is controlled by calendar and flight-hour
constraints.
We agree to clarify the compliance time for newly installed
windows. If a discrepant window is replaced with a new window, then the
initial detailed inspection of the new window must be accomplished
within either 5,500 or 22,000 flight hours after installing the window,
depending on the window part number. The inspection must be repeated at
the interval stated in Table 2 or 3, as applicable, of the Boeing
service bulletin. We have revised paragraph (g) of this AD to clarify
the compliance time.
Request To Include Terminating Action
GKN Aerospace states that it manufactures some of the affected
windows identified in Boeing Alert Service Bulletin 747-56A2012, dated
August 24, 2006. GKN Aerospace states that it is concerned about the
potential removal rates of in-service airplanes to address the unsafe
condition; therefore, it is working to certify an improved window
design that incorporates a new, improved interlayer, which is less
susceptible to the cracking experienced with the existing windows. We
infer the commenter would like us to include a terminating action in
this AD.
We agree that improving the window design to prevent cracking is a
preferable solution than requiring long-term repetitive inspections. In
the preamble of the NPRM, we stated that we considered this action to
be an interim action. When a final action is identified, we may
consider further rulemaking. We have not changed this AD in this
regard.
Request To Skip Inspection To Determine Part Number
Boeing Aerospace Operations Engineering and Logistics Services
requests that we allow operators to skip the window identification
procedure and accomplish the rest of the service bulletin as though the
part number could not be identified. The commenter states that since
some airplanes are equipped with unique No. 2 and No. 3 windows, the
window identification cannot be accomplished according to Part 1 of the
Boeing Alert Service Bulletin 747-56A2012, dated August 24, 2006, or
the replacement according to Part 2, step 4 of the service bulletin.
We do not agree to delete the inspection to determine the part
numbers of the windows. Operators who inspect and determine that the
affected windows are not installed on an airplane are not required to
accomplish the related investigative and corrective actions. Therefore,
accomplishing the inspection to determine the window part numbers may
relieve some operators of the on-condition requirements. However, under
the provisions of paragraph (h) of this AD, we may consider requests
for approval of an alternative method of compliance (AMOC) if
sufficient data are submitted to substantiate that such a design change
would provide an acceptable level of safety. We have not changed this
AD in this regard.
Request To Revise Compliance Times
British Airways states that the compliance times in Tables 2 and 3
of Boeing Alert Service Bulletin 747-56A2012, dated August 24, 2006,
should be revised as follows:
For part numbers (P/Ns) 65B27042-( ) and 65B27043-( ), the
initial inspection should be extended from 5,500 flight hours to 9,000
flight hours.
For P/Ns 65B27046-( ) and 65B27047-( ), the initial
inspection should be reduced from 22,000 flight hours to 15,000 flight
hours, and the repetitive interval should be reduced from 7,500 flight
hours to 3,000 flight hours (to match the repetitive interval for P/Ns
65B27042-( ) and 65B27043-( )).
British Airways asserts that, based on its experience, the longer
compliance times for P/Ns 65B27046-( ) and 65B27047-( ), are not
justified. British Airways also asserts that requiring different
repetitive intervals for different windows does not make sense since
many airlines use a mix of windows on their airplanes.
We acknowledge British Airways' comments but disagree with revising
the compliance times as proposed by the commenter. In developing the
compliance time for this AD action, we considered not only the safety
implications of the identified unsafe condition, but the
recommendations of the manufacturer, known service experience, average
utilization rate of the affected fleet, and the availability of
required parts. British Airways refers to its service experience but
does not provide any data to support its comment. We invite British
Airways to submit, to Boeing, any data it has that supports its
comments related to changing certain compliance times. We would
consider further rulemaking should such data support changing the
compliance times of this AD. To further delay this AD would be
inappropriate considering the need to correct a known safety problem in
a timely manner. Further, operators are always permitted to accomplish
the requirements of an AD at an earlier time than the required
compliance time; therefore, an operator may choose to inspect P/Ns
65B27046-( ) and 65B27047-( ) at repetitive intervals of 3,000 flight
hours. We have determined that the compliance times recommended in the
service bulletin are appropriate for addressing the unsafe condition
and we have not changed this AD in this regard.
Request To Delete Grace Period
British Airways states that the grace period of 1,000 flight hours
after the date on the service bulletin is obsolete, since this time
period will have been exceeded by the time we issued an AD. We infer
that the commenter would like us to delete the grace period from Tables
[[Page 41440]]
2 and 3 of Boeing Alert Service Bulletin 747-56A2012, dated August 24,
2006.
We disagree with deleting the grace period. We would like to point
out that in paragraph (g) of the NPRM, which is retained in this AD, we
stated that the compliance times given in the service bulletin are to
be counted from the effective date of this AD, not from the date on the
service bulletin. We have not changed this AD in this regard.
Request To Rephrase Compliance Time
British Airways requests that we delete the word ``or'' where the
service bulletin compliance times are restated in the ``Relevant
Service Information'' section of the NPRM. As justification, the
commenter states that using the word ``or'' gives an operator the
choice of choosing between two compliance times.
We disagree with revising this AD, since the ``Relevant Service
Information'' section is not retained in a final rule. We have reviewed
the NPRM and find that the wording used throughout the NPRM is
consistent with the service bulletin. Further, where we restated the
service bulletin compliance times in the NPRM, the lead-in statements
clearly specify doing the proposed actions at the earlier of the
compliance times; therefore, the compliance time cannot be chosen at an
operator's discretion. We have not changed this AD in this regard.
Request To Revise Costs of Compliance
British Airways requests that we make the following
changes to the ``Costs of Compliance'' section:
Add the cost of replacing a cracked window. The commenter
states that the ``Costs of Compliance'' section is wrong because it
does not estimate the cost of replacing a cracked window.
Include the cost of having to remove an airplane from
service 40% more frequently to accomplish the repetitive actions.
Revise the estimated work hours. The commenter asserts
that it should take \1/2\ hour to inspect a window to determine its
part number, and that the inspection for cracks would require 2 people
and would take 1 hour.
We do not agree to revise the ``Cost of Compliance'' section as the
commenter proposes. The economic analysis of an AD is limited to the
cost of actions that are actually required. The economic analysis does
not consider the costs of conditional actions, such as repairing a
crack detected during a required inspection (``repair, if necessary'').
Such conditional repairs would be required--regardless of AD
direction--to correct an unsafe condition identified in an airplane and
to ensure that the airplane is operated in an airworthy condition, as
required by the Federal Aviation Regulations. Furthermore, we do not
consider it appropriate to attribute the costs associated with aircraft
``down time'' to the AD. Also, we have determined the cost of
compliance from information contained in the manufacturer's service
information. We recognize that individual operators might incur costs
less than or more than our estimate. It is impossible to estimate such
individual variations. We have not changed this AD in this regard.
Request To Revise Service Bulletin
British Airways submitted several comments on the accuracy and
clarity of Boeing Alert Service Bulletin 747-56A2012, dated August 24,
2006. We infer that the commenter would like us delay issuance of the
AD until the service bulletin is revised to incorporate its comments.
We acknowledge the value of the information submitted by the
commenter. British Airways' comments will be of benefit to any future
revisions of the service bulletin. In this case, however, the service
bulletin is acceptable for ensuring that the unsafe condition is
addressed. Therefore, we do not agree to delay this action until the
service bulletin has been revised. To do so would be inappropriate,
since we have determined that an unsafe condition exists, and that
inspections must be conducted to ensure continued safety. We have not
changed this AD in this regard.
Clarification of AMOC Paragraph
We have revised this action 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 received, and determined that air safety and the public
interest require adopting the AD with the change described previously.
We have determined that this change will neither increase the economic
burden on any operator nor increase the scope of the AD.
Costs of Compliance
There are about 949 airplanes of the affected design in the
worldwide fleet. This AD affects about 153 airplanes of U.S. registry.
The required inspection to determine the window part numbers takes
about 4 work hours per airplane, at an average labor rate of $80 per
work hour. Based on these figures, the estimated cost of the AD for
U.S. operators is $48,960, or $320 per airplane.
The detailed inspection, if necessary, takes about 1 work hour per
airplane, at an average labor rate of $80 per work hour. Based on these
figures, the estimated cost of the detailed inspection for U.S.
operators is $80 per airplane, per inspection cycle, if necessary.
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.
[[Page 41441]]
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 by
adding the following new airworthiness directive (AD):
2007-15-10 Boeing: Amendment 39-15139. Docket No. FAA-2006-26441;
Directorate Identifier 2006-NM-204-AD.
Effective Date
(a) This AD becomes effective September 4, 2007.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D,
747-400F, 747SR, and 747SP series airplanes, certificated in any
category.
Unsafe Condition
(d) This AD results from loss of a No. 3 window in-flight. We
are issuing this AD to detect and correct cracking in the fail-safe
interlayer of certain No. 2 and No. 3 glass windows, which could
result in loss of the window and consequent rapid loss of cabin
pressure. Loss of the window could also result in crew communication
difficulties or incapacitation of the crew.
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.
Inspection, Related Investigative Actions, and Corrective Action
(f) Inspect the No. 2 and No. 3 windows on the left and right
sides of the airplane to determine their part numbers, and do all
the applicable related investigative and corrective actions, by
accomplishing all of the actions specified in the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-56A2012, dated
August 24, 2006, as applicable. Do all of these actions at the
compliance times specified in Tables 1, 2, and 3 of paragraph 1.E.
of the service bulletin, as applicable, except as provided by
paragraph (g) of this AD. A review of airplane maintenance records
is acceptable in lieu of the inspection if the part numbers of the
windows can be conclusively determined from that review. Repeat the
related investigative and corrective actions thereafter at the
interval specified in Table 2 or 3 of the service bulletin, as
applicable.
Exceptions to Compliance Times
(g) Where Tables 1, 2, and 3 of paragraph 1.E. of Boeing Alert
Service Bulletin 747-56A2012, dated August 24, 2006, specify
counting the compliance time from ``. . . after the date on this
service bulletin,'' this AD requires counting the compliance time
from the effective date of this AD. After replacing a discrepant
window with a new window, do the initial detailed inspection of the
new window at the applicable compliance time: (1) within 5,500
flight cycles after installing part number (P/N) 65B27042-( ) or
65B27043-( ), or (2) within 22,000 flight cycles after installing P/
N 65B27046-( ) or 65B27047-( ).
Alternative Methods of Compliance (AMOCs)
(h)(1) The Manager, Seattle Aircraft Certification Office, 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 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.
Material Incorporated by Reference
(i) You must use Boeing Alert Service Bulletin 747-56A2012,
dated August 24, 2006, 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 this
document 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 FAA, Transport Airplane Directorate, 1601
Lind Avenue SW., Renton, Washington; or at the National Archives and
Records Administration (NARA). For information on the availability
of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html
.
Issued in Renton, Washington, on July 18, 2007.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-14426 Filed 7-27-07; 8:45 am]
BILLING CODE 4910-13-P