AD 2004-25-20

[Federal Register Volume 69, Number 243 (Monday, December 20, 2004)]
[Rules and Regulations]
[Pages 75826-75829]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-27506]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-347-AD; Amendment 39-13908; AD 2004-25-20]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Saab Model SAAB 2000 series airplanes. This 
action requires various repetitive inspections for cracking of the drag 
and shear angles that attach the nacelle to the wing, and related 
corrective action. This action also requires eventual modification of 
the drag and shear angles, which would end the repetitive inspections. 
This action is necessary to prevent fatigue cracking of the drag and 
shear angles, which could result in reduced structural integrity of the 
nacelle attachment to the wing. This action is intended to address the 
identified unsafe condition.

DATES: Effective January 24, 2005.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 24, 2005.

ADDRESSES: The service information referenced in this AD may be 
obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Link[ouml]ping, Sweden. 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 
National Archives and Records Administration (NARA). For information on 
the availability of this material at NARA, call (202) 741-6030, or go 
to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.

FOR FURTHER INFORMATION CONTACT: Dan Rodina, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4057; telephone (425) 
227-2125; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD)

[[Page 75827]]

that is applicable to certain Saab Model SAAB 2000 series airplanes was 
published in the Federal Register on May 19, 2004 (69 FR 28860). That 
action proposed to require various repetitive inspections for cracking 
of the drag and shear angles that attach the nacelle to the front spar 
of the wing, and related corrective action. That action also proposed 
to require eventual modification of the drag and shear angles, which 
would end the repetitive inspections.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Request To Allow Temporary Flight With Known Cracking

    The commenter, the manufacturer, states that the Swedish 
airworthiness directives and the Saab service bulletins specify that 
operators may temporarily continue operating an airplane with known 
cracking in the drag and shear angles. The commenter notes that the 
proposed AD does not allow flight with any known cracking. The 
commenter also notes that it is aware of an FAA policy that does not 
allow airplanes to operate with known cracking, but that the FAA has 
allowed deviation from that policy under certain conditions. The 
commenter states that, for the proposed AD, these conditions apply:
    <bullet> The repairs are complicated and time consuming and can 
only be performed during a major maintenance stop.
    <bullet> The cracking is probably caused by secondary local bending 
of the flanges of the angles due to wing deflections.
    <bullet> Analysis shows that the structure will maintain the 
capability to sustain ultimate loads for cracking.
    <bullet> The maximum deferral time before repairing known cracking 
is 20,000 flights.
    <bullet> Repair methods and terminating action have been identified 
and repair material is available for operators.
    We infer that the commenter is requesting that the proposed AD be 
revised to allow temporary flight with known cracking.
    We agree. While it is not our normal policy to allow flight with 
known cracking, based upon our review of the substantiating data 
submitted by the manufacturer, we have determined that we can allow 
temporary flight with known cracking within the limits specified in the 
applicable Saab service bulletins. We have determined that, if the 
crack size limits are strictly observed, and if repetitive inspections 
are performed at the required intervals, cracking that grows beyond the 
specified limits will be detected, and corrective action taken, before 
the cracking can grow to a size that would create an unacceptable risk 
of structural failure. Paragraph (c) of this final rule allows 
temporary flight with known cracking within the limits specified in the 
applicable Saab service bulletins.

Request To Clarify Compliance Time for Initial Inspections

    The commenter requests that the compliance times specified in 
paragraphs (b)(2) and (b)(3) of the proposed AD be changed to include 
the phrases ``but not later than at 14,500 flight cycles'' and ``but 
not later than at 11,000 flight cycles,'' respectively. The commenter 
did not provide any justification for this request.
    We agree with the commenter's request to add the phrases stated 
above to paragraphs (b)(2) and (b)(3) of this final rule. Upon review 
of the compliance times specified in the applicable service bulletins, 
we find that this information was inadvertently omitted from the 
compliance times stated in the proposed AD. We have determined that 
including this information in this final rule imposes no additional 
burden on any U.S.-registered airplane because none of these airplanes 
have accumulated the number of flight cycles that would make these 
provisions applicable. This change also provides harmonization between 
the Swedish airworthiness directives, Saab service bulletins, and this 
final rule.

Request To Clarify Unsafe Condition

    The commenter suggests that the unsafe condition statement in the 
Summary and Discussion sections and the body of the proposed AD be 
changed to include the phrase ``attachment to the wing.'' The commenter 
states that it is the integrity of the attachment of the nacelle to the 
wing that can be reduced, not the structural integrity of the nacelle 
or the wing.
    We agree. The unsafe condition in the Summary, Discussion, and body 
sections of the proposed AD states ``This action is necessary to 
prevent fatigue cracking of the drag and shear angles, which could 
result in reduced structural integrity of the nacelle and wing.'' The 
unsafe condition statement in the Summary and body of this final rule 
is ``To prevent fatigue cracking of the drag and shear angles, which 
could result in reduced structural integrity of the nacelle attachment 
to the wing.'' The Discussion section is not restated in this final 
rule, so no change to the final rule is necessary in this regard.

Request for Changes to Paragraph (a)

    The commenter requests that, after the word ``fasteners'' in 
paragraph (a)(1) of the proposed AD, the words ``and in the radius of 
the shear angle'' be included. The commenter also requests that, after 
the words ``around the fasteners'' in paragraph (a)(2) of the proposed 
AD, the words ``as applicable'' be included. The commenter did not 
provide any justification for the request. We infer that the commenter 
requests these changes for clarification purposes.
    We agree. Paragraph (a)(1) of this final rule includes the words 
``and in the radii of the shear angles.'' (We have pluralized the 
wording since more than one angle is being inspected.) Paragraph (a)(2) 
of this final rule includes the words ``where applicable.''

Request To Clarify Termination of Repetitive Inspections

    The commenter requests that the Summary section of the proposed AD 
be changed to clarify that the terminating action specified in the 
proposed AD would only end the repetitive inspections identified in the 
Saab service bulletins. The commenter states that the structural 
inspection program will continue to require inspections of the drag and 
shear angles.
    We do not agree with the commenter's request to change the proposed 
AD to specify that only the repetitive inspections identified in the 
service bulletins will be terminated. Paragraph (e) of the proposed AD, 
which is the Terminating Action paragraph, clearly states, 
``Accomplishment of these modifications ends the repetitive inspections 
required by paragraphs (a) and (b) of this AD.'' Furthermore, an AD is 
not the vehicle for terminating inspections in operators' maintenance 
programs. No change to the final rule is necessary in this regard.

Request To Include Reporting Information to the Manufacturer

    The commenter notes that the proposed AD does not include a 
reporting requirement. The Saab service bulletins referenced in the 
proposed AD include instructions for reporting inspection information 
to the manufacturer. The commenter states that feedback from operators 
is important to ``keep a high confidence in the analysis and to be able 
to plan supply of repair and modification material.'' We infer that the 
commenter requests that the proposed AD include a reporting 
requirement.

[[Page 75828]]

    We do not agree. We understand the need for manufacturers to 
collect useful data; however, we do not require this information. The 
Paperwork Reduction Act requires agencies to consider the extent of the 
paperwork burden that will accompany any new rule. This Act is intended 
to reduce these burdens by requiring agencies not only to analyze the 
information collection and reporting costs they are imposing on the 
private sector, but also to use those analyses to minimize the cost. 
Since we do not need the information regarding the inspection findings, 
we will not include a reporting requirement in this final rule. 
Operators may voluntarily submit inspection results to the 
manufacturer.

Request To Change Explanation of Relevant Service Information

    The commenter requests the following changes to the Explanation of 
Relevant Service Information section of the proposed AD:
    <bullet> Delete `` * * * and related corrective action'' in the 
first paragraph. This paragraph discusses the procedures included in 
Saab Service Bulletins 2000-54-026 and 2000-54-028, both Revision 01, 
both dated June 20, 2002. The commenter notes that the corrective 
actions are included in Saab Service Bulletins 2000-54-027 and 2000-54-
029, both dated November 4, 2002.
    <bullet> Change the order of the procedures in the second paragraph 
so the order of the procedures correlates to the order of the service 
bulletin references. The commenter suggests, ``Additionally, the 
manufacturer has issued Service Bulletins 2000-54-027 and 2000-54-029, 
both dated November 4, 2002, which describe procedures for modification 
of the shear angles and of the upper and lower drag angles.'' The 
commenter notes that Service Bulletin 2000-54-027 addresses 
modification of the shear angles and Service Bulletin 2000-54-029 
addresses modification of the upper and lower drag angles.
    <bullet> Delete the parenthetical reference, ``rotating probe,'' 
that appears in the second paragraph. The commenter states that this 
phrase is not applicable.
    <bullet> Change the last sentence of the second paragraph to ``If 
any cracking is found, repair and modifications of the drag angles are 
detailed in the associated service bulletins. Both service bulletins 
describe procedures for determining the length and position of each 
crack and sending a report to the manufacturer.''
    We agree with the commenter's suggestions. However, since the 
Explanation of Relevant Service Information section of the proposed AD 
is not restated in this final rule, no change to this final rule is 
necessary in this regard.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    We estimate that 3 airplanes of U.S. registry will be affected by 
this AD.
    It will take about 6 work hours per airplane to do the inspections, 
at an average labor rate of $65 per work hour. Based on these figures, 
the cost impact of the inspections on U.S. operators is estimated to be 
$1,170, or $390 per airplane, per inspection cycle.
    It will take about 40 work hours per airplane to do the 
modification of the shear angles, at an average labor rate of $65 per 
work hour. Required parts will cost about $6,200 per airplane. Based on 
these figures, the cost impact of the modification on U.S. operators is 
estimated to be $26,400, or $8,800 per airplane.
    It will take about 400 work hours per airplane to do the 
modification of the drag angles, at an average labor rate of $65 per 
work hour. Required parts will cost about $41,794 per airplane. Based 
on these figures, the cost impact of the modification on U.S. operators 
is estimated to be $203,382, or $67,794 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. 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

    The FAA's authority to issue rules regarding aviation safety is 
found in Title 49 of the United States Code. 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.
    This rulemaking is promulgated under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, the FAA is charged 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 AD.

Regulatory Impact

    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    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

0
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

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. Section 39.13 is amended by adding the following new airworthiness 
directive:

2004-25-20 Saab Aircraft AB: Amendment 39-13908. Docket 2002-NM-347-
AD.


[[Page 75829]]


    Applicability: Model SAAB 2000 series airplanes, certificated in 
any category, serial numbers -004 through -063 inclusive.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue cracking of the drag and shear angles of the 
wing, which could result in reduced structural integrity of the 
nacelle attachment to the wing, accomplish the following:

Repetitive Inspections

    (a) Do the inspections required by paragraphs (a)(1) and (a)(2) 
of this AD, at the applicable time specified in paragraph (b) of 
this AD.
    (1) Do a detailed inspection for cracking of the shear angles 
which attach the nacelle to the front spar of the wing, and an eddy 
current inspection for cracking around the fasteners and in the 
radii of the shear angles, by doing all the actions per the 
Accomplishment Instructions of Saab Service Bulletin 2000-54-026, 
Revision 01, dated June 20, 2002.
    (2) Do an endoscope inspection of the upper and lower drag 
angles for cracking, and an eddy current inspection for cracking 
around the fasteners where applicable, by doing all the actions per 
the Accomplishment Instructions of Saab Service Bulletin 2000-54-
028, Revision 01, dated June 20, 2002.

    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.''

Compliance Times

    (b) Do the inspections required by paragraph (a) of this AD at 
the applicable compliance time specified in paragraph (b)(1), 
(b)(2), or (b)(3) of this AD. Repeat the inspections thereafter at 
intervals not to exceed 4,000 flight cycles until the modification 
required by paragraph (e) of this AD is done.
    (1) For airplanes that have accumulated 14,000 or more total 
flight cycles as of the effective date of this AD: Inspect within 
500 flight cycles after the effective date of this AD.
    (2) For airplanes that have accumulated 10,000 or more total 
flight cycles, but fewer than 14,000 total flight cycles as of the 
effective date of this AD: Inspect within 1,000 flight cycles after 
the effective date of this AD, but not later then 14,500 total 
flight cycles.
    (3) For airplanes that have accumulated fewer than 10,000 total 
flight cycles as of the effective date of this AD: Inspect within 
2,000 flight cycles after the effective date of this AD, but not 
later then 11,500 total flight cycles.

Corrective Action

    (c) If any cracking is found during any inspection required by 
this AD: Except as provided by paragraph (f) of this AD, do the 
actions specified in and at the times specified in Table 1 of the 
Accomplishment Instructions of Saab Service Bulletin 2000-54-026, 
Revision 01, dated June 20, 2002; or Saab Service Bulletin 2000-54-
028, Revision 01, dated June 20, 2002; as applicable. Where the 
service bulletins specify to contact the manufacturer, before 
further flight, repair the cracking in accordance with a method 
approved by either the Manager, International Branch, ANM-116, 
Transport Airplane Directorate, FAA; or the Luftfartsverket (or its 
delegated agent). Instead of repairing the cracking, doing the 
modifications required by paragraph (e) of this AD before further 
flight, terminates the repetitive inspections required by paragraphs 
(a) and (b) of this AD.

Inspections Done Per Previous Issues of Service Bulletins

    (d) Inspections done before the effective date of this AD per 
Saab Service Bulletins 2000-54-026 and 2000-54-028, both dated April 
26, 2002, are considered acceptable for compliance with the 
corresponding actions specified in this AD.

Terminating Action

    (e) Except as provided by paragraph (c) of this AD: Do the 
modifications of the drag and shear angles of the wing at the times 
specified in paragraphs (e)(1) and (e)(2) of this AD. Accomplishment 
of these modifications ends the repetitive inspections required by 
paragraphs (a) and (b) of this AD.
    (1) Before the accumulation of 20,000 total flight cycles: 
Modify the shear angles that attach the nacelle to the front spar of 
the wing by doing all the actions per the Accomplishment 
Instructions of Saab Service Bulletin 2000-54-027, dated November 4, 
2002.
    (2) Before the accumulation of 24,000 total flight cycles: 
Modify the upper and lower drag angles by doing all the actions per 
the Accomplishment Instructions of Saab Service Bulletin 2000-54-
029, dated November 4, 2002.

No Reporting Requirement

    (f) Although the Saab service bulletins referenced in this AD 
recommend submitting certain information to the manufacturer, this 
AD does not include such a requirement.

Alternative Methods of Compliance

    (g) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, is authorized to approve alternative methods of 
compliance for this AD.

Incorporation by Reference

    (h) Unless otherwise specified in this AD, the actions shall be 
done in accordance with the service bulletins listed in Table 1 of 
this AD.

          Table 1.--Service Bulletins Incorporated by Reference
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                              Revision level--
   Saab service bulletin--                               Date--
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2000-54-026.................  01.............  June 20, 2002.
2000-54-027.................  Original.......  November 4, 2002.
2000-54-028.................  01.............  June 20, 2002.
2000-54-029.................  Original.......  November 4, 2002.
------------------------------------------------------------------------

    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 Saab Aircraft AB, SAAB Aircraft 
Product Support, S-581.88, Link[ouml]ping, Sweden. Copies may be 
inspected 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: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.

    Note 2: The subject of this AD is addressed in Swedish 
airworthiness directives 1-174 and 1-175, both effective April 30, 
2002; and Swedish airworthiness directives 1-1180 and 1-181, both 
effective November 8, 2002.

Effective Date

    (i) This amendment becomes effective on January 24, 2005.

    Issued in Renton, Washington, on December 6, 2004.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-27506 Filed 12-17-04; 8:45 am]
BILLING CODE 4910-13-P