[Federal Register Volume 62, Number 148 (Friday, August 1, 1997)]
[Rules and Regulations]
[Pages 41255-41257]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20129]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-18-AD; Amendment 39-10096; AD 97-16-05]
RIN 2120-AA64


Airworthiness Directives; Gulfstream Aerospace Corporation Model 
G-159 (G-I) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to all Gulfstream Model G-159 (G-I) airplanes, that 
currently requires repetitive inspections to detect corrosion in the 
wing planks under the bottom wing center fairings, and repair, if 
necessary. This amendment requires the installation of a protective 
paint system which, when accomplished, will allow the inspections to be 
conducted at longer intervals. This amendment is

[[Page 41256]]

prompted by the development of a modification that will improve the 
corrosion resistance of the subject area. The actions specified by this 
AD are intended to detect and prevent corrosion in the lower skins of 
the wing center section. If corrosion in this area remains unchecked, 
it could reduce the integrity of the wing-to-fuselage fitting, and 
consequently could lead to separation of the wing from the airplane.

DATES: Effective September 5, 1997.

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 5, 1997.

ADDRESSES: The service information referenced in this AD may be 
obtained from Gulfstream Aerospace Corporation, Technical Operations 
Department, P.O. Box 2206, M/S D-10, Savannah, Georgia 31402-2206. This 
information may be examined at the Federal Aviation Administration 
(FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, Atlanta Aircraft Certification 
Office, Small Airplane Directorate, Campus Building, 1701 Columbia 
Avenue, Suite 2-160, College Park, Georgia; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Christina Marsh, Aerospace Engineer, 
Airframe and Propulsion Branch, ACE-117A, FAA, Atlanta Aircraft 
Certification Office, Small Airplane Directorate, Campus Building, 1701 
Columbia Avenue, Suite 2-160, College Park, Georgia 30337-2748; 
telephone (404) 305-7362; fax (404) 305-7348.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 67-04-01, 
amendment 39-1234 (36 FR 12688, July 3, 1971), which is applicable to 
all Gulfstream Model G-159 (G-I) airplanes, was published in the 
Federal Register on March 6, 1997 (62 FR 10224). The action proposed to 
continue to require the repetitive visual inspections, specified in AD 
67-04-01, to detect corrosion of the wing planks under the bottom wing 
center fairing assemblies, and repair, if necessary.
    For airplanes on which a protective paint system had not been 
installed previously, the action proposed to require that the 
inspection continue to be repeated at intervals of 6 months (26 weeks), 
until a protective paint system is installed within 12 months. Once the 
paint system is installed, the repetitive inspections were proposed to 
be required to continue, but the repetitive interval would be extended 
to 18 months.
    For airplanes on which a protective paint system was installed 
previously, the action proposed to extend the currently-required 
repetitive inspection interval of 12 months to 18 months.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

Conclusion

    The FAA has determined that air safety and the public interest 
require the adoption of the rule as proposed.

Cost Impact

    There are approximately 146 Gulfstream Model G-159 airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 72 
airplanes of U.S. registry will be affected by this AD.
    The inspections that are currently required by AD 67-04-01, and 
those that are required by this action, take approximately 40 work 
hours per airplane to accomplish, at an average labor rate of $60 per 
work hour. Based on these figures, the cost impact of the required 
inspection actions on U.S. operators is estimated to be $172,800, or 
$2,400 per airplane, per inspection.
    The installation of the protective paint system that is required by 
this AD action will take approximately 30 work hours per airplane to 
accomplish, at an average labor rate of $60 per work hour. Required 
materials will cost approximately $100 per airplane. Based on these 
figures, the cost impact of this requirement of this AD on U.S. 
operators is estimated to be $136,800, or $1,900 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action 
and it is contained in the rules docket. A copy of it may be obtained 
from the rules docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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 removing amendment 39-1234 (36 FR 
12688, July 3, 1971), and by adding a new airworthiness directive (AD), 
amendment 39-10096, to read as follows:

97-16-05 Gulfstream Aerospace Corporation: Amendment 39-10096. 
Docket 97-NM-18-AD. Supersedes AD 67-04-01, Amendment 39-1234.

    Applicability: All Model G-159 (G-I) airplanes, certificated in 
any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (d)(1) 
of this AD. The request should include an assessment of the effect 
of the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.

[[Page 41257]]

    To detect and prevent corrosion in the lower skins of the wing 
center section, which could reduce the integrity of the wing-to-
fuselage fitting and consequently could lead to separation of the 
wing from the airplane, accomplish the following:
    (a) For all airplanes: Within 4 weeks after July 3, 1971 (the 
effective date of AD 67-04-01, amendment 39-1234), remove the bottom 
wing center fairings having part numbers (P/N) 159W10400-121 and 
159W10401-121, or use an FAA-approved equivalent method, to perform 
a visual inspection to detect corrosion of the wing planks under 
these fairings.
    Note 2: Paragraph (a) of this AD merely restates the actions 
previously required by AD 67-04-01, amendment 39-1234. As allowed by 
the phrase, ``unless accomplished previously,'' if those 
requirements of AD 67-04-01 have already been accomplished, this AD 
does not require that those actions be repeated.
    Note 3: Care must be exercised when removing the fairings, since 
the attaching rivets go into the pressure vessel. Use caution not to 
enlarge rivet holes when removing rivets. When reinstalling the 
fairings, an adequate type fastener and sealant must be used.
    Note 4: Grumman Service Newsletter, Volume 166, dated August-
September 1966, pertains to this subject.

    (b) For airplanes on which a protective paint system has not 
been installed in accordance with Grumman Gulfstream I Aircraft 
Service Change No. 190, dated June 28, 1971: Accomplish paragraphs 
(b)(1) and (b)(2) of this AD. As of the effective date of this AD, 
the inspections required by this paragraph shall be accomplished in 
accordance with Grumman Gulfstream I Aircraft Service Change No. 
190, dated June 28, 1971.

    Note 5: The repeated inspection referred to in this paragraph is 
the same inspection previously required by AD 67-04-01. Paragraph 
(b)(1) of this AD merely restates the requirement of AD 67-04-01 to 
repeat the inspection at intervals of 6 months. Paragraph (b)(2) 
permits the reinspection interval to be extended to 18 months once 
the specified protective paint system is installed.

    (1) As a result of the inspection required by paragraph (a) of 
this AD:
    (i) If no corrosion is detected, repeat the inspection 
thereafter at intervals not to exceed 6 months (26 weeks) until the 
actions specified in paragraph (b)(2) of this AD are accomplished.
    (ii) If any corrosion is detected, prior to further flight, 
either repair the corroded part with an FAA-approved repair; or 
replace the corroded part with a new or serviceable part of the same 
part number; or replace the corroded part with a part approved by 
the FAA. Thereafter, continue to perform the inspection at intervals 
not to exceed 6 months (26 weeks) until paragraph (b)(2) of this AD 
is accomplished.
    (2) Within 12 months after the effective date of this AD, 
install the protective paint system in accordance with Grumman 
Gulfstream I Aircraft Service Change No. 190, dated June 28, 1971. 
After installation, continue to perform the inspection required by 
this paragraph at intervals not to exceed 18 months.
    (c) For airplanes on which a protective paint system has been 
installed previously in accordance with Grumman Gulfstream I 
Aircraft Service Change
    No. 190, dated June 28, 1971: Accomplish paragraphs (c)(1) and 
(c)(2) of this AD. As of the effective date of this AD, the 
inspections required by this paragraph shall be accomplished in 
accordance with Grumman Gulfstream I Aircraft Service Change No. 
190, dated June 28, 1971.
    Note 6: The repeated inspection referred to in this paragraph is 
the same inspection previously required by AD 67-04-01. Paragraph 
(c)(1) of this AD merely restates the requirement of AD 67-04-01 to 
repeat the inspection at intervals of 12 months. Paragraph (c)(2) 
permits the reinspection interval to be extended to 18 months.
    (1) As a result of the inspection required by paragraph (a) of 
this AD:
    (i) If no corrosion is detected, repeat the inspection 
thereafter at intervals not to exceed 12 months until paragraph 
(c)(2) of this AD is accomplished.
    (ii) If any corrosion is detected, prior to further flight, 
either repair the corroded part with an FAA-approved repair; or 
replace the corroded part with a new or serviceable part of the same 
part number; or replace the corroded part with a part approved by 
the FAA. Thereafter, continue to perform the inspection at intervals 
not to exceed 12 months until paragraph (c)(2) of this AD is 
accomplished.
    (2) Within 18 months since the last inspection accomplished in 
accordance with paragraph (c)(1) of this AD (i.e., the last 
inspection accomplished in accordance with AD 67-04-01), repeat the 
inspection specified in paragraph (c)(1) of this AD.
    (i) If no corrosion is detected, repeat the inspection 
thereafter at intervals not to exceed 18 months.
    (ii) If any corrosion is detected, prior to further flight, 
repair in accordance with the service change. After repair, continue 
to perform the inspection at intervals not to exceed 18 months.
    (d)(1) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Atlanta Aircraft Certification 
Office (ACO), FAA, Small Airplane Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Atlanta ACO.
    (2) Alternative methods of compliance, approved previously in 
accordance with AD 67-04-01, amendment 39-1234, are approved as 
alternative methods of compliance with this AD.
    Note 7: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.
    (e) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

    (f) The actions shall be done in accordance with Grumman 
Gulfstream I Aircraft
    Service Change No. 190, dated June 28, 1971. This incorporation 
by reference was approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from Gulfstream Aerospace Corporation, Technical Operations 
Department, P.O. Box 2206, M/S D-10, Savannah, Georgia 31402-2206. 
Copies may be inspected at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Atlanta 
Aircraft Certification Office, Small Airplane Directorate, Campus 
Building, 1701 Columbia Avenue, Suite 2-160, College Park, Georgia; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on September 5, 1997.

    Issued in Renton, Washington, on July 25, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-20129 Filed 7-31-97; 8:45 am]
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