[Federal Register: July 12, 2006 (Volume 71, Number 133)]
[Proposed Rules]
[Page 39242-39244]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12jy06-23]
[[Page 39242]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-NM-143-AD]
RIN 2120-AA64
Airworthiness Directives; Gulfstream Aerospace Model G-159
Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Supplemental notice of proposed rulemaking; reopening of
comment period.
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SUMMARY: This document revises an earlier supplemental notice of
proposed rulemaking (NPRM), applicable to all Gulfstream Aerospace
Corporation Model G-159 airplanes, that would have required repetitive
non-destructive testing inspections to detect corrosion of the skin of
certain structural assemblies, and corrective action if necessary. The
first supplemental NPRM also would have required x-ray and ultrasonic
inspections to detect corrosion and cracking of the splicing of certain
structural assemblies, and repair if necessary. This new action revises
the proposed rule by limiting the time certain repetitive inspections
may be repeated before corrective action must be taken. The actions
specified by this new proposed supplemental AD are intended to detect
and correct corrosion and cracking of the lower wing plank splices and
spot-welded skins of certain structural assemblies, which could result
in reduced controllability of the airplane. This action is intended to
address the identified unsafe condition.
DATES: Comments must be received by August 7, 2006.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 96-NM-143-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. 96-NM-143-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 Gulfstream Aerospace Corporation, Technical Publications
Dept., P.O. Box 2206, Savannah, Georgia 31402-2206. This information
may be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington; or at the FAA, Atlanta Aircraft
Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite
450, Atlanta, Georgia.
FOR FURTHER INFORMATION CONTACT: Michael Cann, Aerospace Engineer,
Airframe Branch, ACE-117A, FAA, Atlanta Aircraft Certification Office,
One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia
30349; telephone (770) 703-6038; fax (770) 703-6097.
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 Docket Number 96-NM-143-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this second supplemental NPRM by
submitting a request to the FAA, Transport Airplane Directorate, ANM-
114, Attention: Rules Docket No. 96-NM-143-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
Discussion
A proposal to amend part 39 of the Federal Aviation Regulations (14
CFR part 39) to add an airworthiness directive (AD), applicable to all
Gulfstream Aerospace Corporation Model G-159 airplanes, was published
as a supplemental notice of proposed rulemaking (NPRM) in the Federal
Register on March 21, 2006 (71 FR 14123). The first supplemental NPRM
would have required repetitive non-destructive testing inspections to
detect corrosion of the skin of certain structural assemblies, and
corrective action if necessary. The first supplemental NPRM also would
have required x-ray and ultrasonic inspections to detect corrosion and
cracking of the splicing of certain structural assemblies, and repair
if necessary. The first supplemental NPRM was prompted by reports
indicating corrosion had been detected in a larger area than previously
reported. That condition, if not detected and corrected, could result
in cracking of the lower wing plank splices and spot-welded skins of
certain structural assemblies, which could result in reduced
controllability of the airplane. That action was intended to address
the identified unsafe condition.
Comments
Due consideration has been given to the comments received in
response to the first supplemental NPRM.
Request To Clarify Paragraph (a)(3) of the Supplemental NPRM
The manufacturer, Gulfstream, requests that the inspection
specified in paragraph (a)(3) of the NPRM be revised to specify that
the airplane may remain in service for up to 18 months with a proviso
that repeat x-ray inspections are accomplished at 9-month intervals
until rework or replacement is accomplished.
We agree that further clarification is necessary for paragraph
(a)(3) of this second supplemental NPRM and have revised paragraph
(a)(3) accordingly.
[[Page 39243]]
Request To Clarify the Areas of Inspection
The same commenter, Gulfstream, would like us to clarify the
``Summary'' section of the first supplemental NPRM. The commenter
states that Customer Bulletin (CB) 337B, dated August 17, 2005 expands
only the wing lower plank inspection from WS 40 to WS 310. Gulfstream
points out that all other areas identified within CB 337, Revision B,
were established as part of the original CB inspection criteria.
We acknowledge the commenter's point. However, the intent of the
first supplemental NPRM was to specify that the wing lower plank
inspection was being added to the proposed requirements of the original
NPRM. The proposed requirements are in accordance with Gulfstream GI CB
337B, dated August 17, 2005. No change is necessary to this
supplemental NPRM as a result of that comment.
Request To Clarify Reference to ``Exfoliation'' Corrosion
Gulfstream also requests that we clarify the reference to
``exfoliation'' in the ``Relevant Customer Bulletin'' section of the
preamble of the supplemental NPRM by changing the reference to ``inter-
granular/exfoliation'' corrosion. Gulfstream states that, in order to
convey the nature of this type of corrosion, it is important to
understand that inter-granular starts first with the visible result,
exfoliation, typically following significant structural damage.
Gulfstream further notes that inter-granular corrosion often cannot be
visibly seen as it goes down from the surface, transitions sideways
following the boundary layer for a distance, and cannot be seen without
non-destructive testing (NDT) inspection.
We acknowledge the commenter's clarification regarding the
reference to exfoliation in the supplemental NPRM. However, since the
description of the ``Relevant Customer Bulletin'' does not reappear in
this supplemental NPRM, it is unnecessary to revise this supplemental
NPRM.
Request To Clarify ``Difference Between the CB and the Proposed AD''
Gulfstream also notes that Gulfstream GI CB 337 refers to the
Airplane Maintenance Manual (AMM), Chapter 05, which specifies
corrective actions and follow-up inspection intervals.
We infer that Gulfstream would like us to clarify that, while the
CB does not explicitly specify repetitive inspections, the CB does
refer to the AMM, which contains certain corrective actions and
repetitive inspection intervals. We acknowledge that Gulfstream CB
337B, dated August 17, 2005, refers to the AMM, and that the AMM
specifies certain repetitive inspection intervals. Since the
``Differences Between the CB and the Proposed AD'' section does not
reappear in this supplemental AD, no change to this supplemental NPRM
is necessary.
Request To Change Reporting Address
Gulfstream requests that we update the address where the reporting
requirements are to be sent.
We agree to change the address for the reporting requirements and
have revised this supplemental NPRM accordingly.
Editorial Change
We have also revised paragraph (f) of this supplemental NPRM to
remove the phrase, ``as defined by paragraphs (f)(1) and (f)(2) of this
AD:''. That phrase was intended to define new lower wing planks based
on when the new lower wing planks were installed. We removed that
phrase, since the compliance time (within 144 months after replacement
of the lower wing planks with new lower wing planks, or within 9 months
after the effective date of this AD, whichever occurs later) is the
same for all new lower wing planks.
Conclusion
Since these changes expand the scope of the first supplemental
NPRM, the FAA has determined that it is necessary to reopen the comment
period to provide additional opportunity for public comment.
Changes to 14 CFR Part 39/Effect on the Proposed AD
On July 10, 2002, the FAA issued a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness
directives system. The regulation now includes material that relates to
altered products, special flight permits, and alternative methods of
compliance (AMOCs). These changes are reflected in this supplemental
NPRM.
Explanation of Change to Costs of Compliance
After the first supplemental NPRM was issued, we reviewed the
figures we have used over the past several years to calculate AD costs
to operators. To account for various inflationary costs in the airline
industry, we find it necessary to increase the labor rate used in these
calculations from $65 per work hour to $80 per work hour. The cost
impact information, below, reflects this increase in the specified
hourly labor rate.
Cost Impact
There are approximately 52 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 25 airplanes of U.S. registry
would be affected by this proposed AD, that it would take approximately
between 300 and 450 work hours per airplane, depending upon how many
spot-welded skins have been replaced with bonded skin panels, to
accomplish the proposed actions, and that the average labor rate is $80
per work hour. Based on these figures, the cost impact of the proposed
AD on U.S. operators is estimated to be between $600,000 and $900,000,
or between $24,000 and $36,000 per airplane per inspection cycle.
The cost impact figure discussed above is 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 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.
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 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,
[[Page 39244]]
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:
Gulfstream Aerospace Corporation: Docket 96-NM-143-AD.
Applicability: All Model G-159 airplanes, certificated in any
category.
Compliance: Required as indicated, unless accomplished
previously.
To detect and correct corrosion and cracking of the spot-welded
skins of the lower wing plank splices and certain structural
assemblies, which could result in reduced controllability of the
airplane, accomplish the following:
Note 1: A note in the Accomplishment Instructions of the
Gulfstream customer bulletin instructs operators to contact
Gulfstream if any difficulty is encountered in accomplishing the
customer bulletin. However, any deviation from the instructions
provided in the customer bulletin must be approved as an alternative
method of compliance (AMOC) under paragraph (h) of this AD.
Non-Destructive Testing Inspections of the Fuselage, Empennage, and
Flight Controls
(a) Within 9 months after the effective date of this AD, perform
a non-destructive test (NDT) to detect corrosion of the skins of the
elevators, ailerons, rudder and rudder trim tab, flaps, aft lower
fuselage, and vertical and horizontal stabilizers; in accordance
with the Accomplishment Instructions of Gulfstream GI Customer
Bulletin (CB) 337B, including Appendix A, dated August 17, 2005. The
corrosion criteria must be determined by the Manager, Atlanta
Aircraft Certification Office (ACO), FAA. Gulfstream Tool ST905-377
is also an acceptable method of determining the corrosion criteria.
(1) If no corrosion or cracking is detected, repeat the
inspection thereafter at intervals not to exceed 18 months.
(2) If any corrosion is detected that meets the criteria of
``light'' or ``mild'' corrosion, repeat the NDT inspections of that
component thereafter at intervals not to exceed 12 months.
(3) If any corrosion is detected that meets the criteria of
``moderate'' corrosion: Within 9 months after the initial
inspection, repeat the NDT inspection of that component, and within
18 months since the initial inspection, repair or replace the
component with a serviceable component in accordance with the CB.
(4) If any corrosion is detected that meets the criteria of
``severe'' corrosion, before further flight, replace the component
with a serviceable component in accordance with the CB.
Existing Repairs
(b) If any existing repairs are found during the inspections
required by paragraph (a) of this AD, before further flight, ensure
that the repairs are in accordance with a method approved by the
Manager, Atlanta ACO.
Inspections of the Lower Wing Plank
(c) Except as provided in paragraph (f) of this AD: Within 9
months after the effective date of this AD, perform NDT inspections
to detect corrosion and cracking of the lower wing plank splices, in
accordance with the Accomplishment Instructions of Gulfstream GI CB
337B, including Appendix A, dated August 17, 2005.
(1) If no corrosion or cracking is detected, repeat the NDT
inspection at intervals not to exceed 18 months.
(2) If any corrosion or cracking is detected, before further
flight, perform all applicable investigative actions and corrective
actions in accordance with the customer bulletin.
Repair Removal Threshold
(d) For repairs specified in Appendix A of Gulfstream GI CB
337B, dated August 17, 2005: Within 144 months after the date of the
repair installation, remove the repaired component and replace it
with a new or serviceable component, in accordance with Gulfstream
GI CB 337B, including Appendix A, dated August 17, 2005.
Prior Blending in the Riser Areas
(e) If, during the performance of the inspections required by
paragraph (c) or (f) of this AD, the inspection reveals that prior
blending has been performed on the riser areas: Before further
flight, perform an eddy current or fluorescent penetrant inspection,
as applicable, to evaluate the blending, and accomplish appropriate
corrective actions, in accordance with the Accomplishment
Instructions of Gulfstream GI CB 337B, including Appendix A, dated
August 17, 2005. If any blend-out is outside the limits specified in
the CB, before further flight, repair in a manner approved by the
Manager, Atlanta ACO.
For Airplanes With New Lower Wing Planks
(f) For airplanes with new lower wing planks: Within 144 months
after replacement of the lower wing planks with new lower wing
planks, or within 9 months after the effective date of this AD,
whichever occurs later, perform all of the actions, including any
other related investigative actions and corrective actions,
specified in paragraph (c) of this AD.
Reporting Requirement
(g) Within 30 days of performing the inspections required by
this AD: Submit a report of inspection findings (both positive and
negative) to Gulfstream Aerospace Corporation; Attention: Technical
Operations--Structures Group, Dept. 893, Mail Station D-25, 500
Gulfstream Road, Savannah, Georgia 31408. Information collection
requirements contained in this regulation have been approved by the
Office of Management and Budget (OMB) under the provisions of the
Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have
been assigned OMB Control Number 2120-0056.
Alternative Methods of Compliance
(h)(1) The Manager, Atlanta 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.
Issued in Renton, Washington, on June 30, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-10911 Filed 7-11-06; 8:45 am]
BILLING CODE 4910-13-P