[Federal Register: September 28, 2004 (Volume 69, Number 187)]
[Proposed Rules]               
[Page 57892-57894]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28se04-27]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-182-AD]
RIN 2120-AA64

 
Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

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

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 
340B series airplanes, that would have required replacement of the 
retract actuator bracket attachment bolt (RABAB) of the main landing 
gear (MLG) with a new RABAB, and reidentification of the MLG shock 
strut. This new action revises the proposed rule by referencing new 
service information; and by adding an inspection for corrosion, 
fretting, or other damage of any RABAB installed in accordance with the 
old service information; and applicable corrective actions. The actions 
specified by this new proposed AD are intended to prevent failure of 
the RABAB, which could result in loosening of the actuator bracket and 
consequent failure of the MLG to retract, with considerable damage to 
other landing gear parts, including the MLG trunnion fitting. This 
action is intended to address the identified unsafe condition.

DATES: Comments must be received by October 25, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-182-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. 2002-NM-182-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 Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Link''ping, Sweden. This information may be examined at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Dan Rodina, Aerospace Engineer; 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2125; fax (425) 227-1149.

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 2002-NM-182-AD.'' The postcard will be date stamped 
and returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2002-NM-182-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 
certain Saab Model SAAB SF340A and SAAB 340B series airplanes, was 
published as a notice of proposed rulemaking (NPRM) in the Federal 
Register on April 15, 2004 (69 FR 19952). That NPRM would have required 
replacement of the retract actuator bracket attachment bolt (RABAB) of 
the main landing gear (MLG) with a new RABAB, and reidentification of 
the MLG shock strut. That NPRM was prompted by reports of failures of 
the RABAB of the MLG due to hydrogen embrittlement. This can be caused 
by failure to fully de-embrittle after electroplating the RABAB during 
manufacture. That condition, if not corrected, could result in 
loosening of the retract actuator bracket and consequent failure of the 
MLG to retract, with considerable damage to other landing gear parts, 
including the MLG trunnion fitting.

[[Page 57893]]

Actions Since Issuance of Previous Proposal

    Since the issuance of the original NPRM, the Luftfartsverket (LFV), 
which is the airworthiness authority for Sweden, notified us of reports 
of failures of RABABs that were replaced in accordance with Saab 
Service Bulletin 340-32-124, Revision 01, dated May 21, 2002 (which the 
original NPRM refers to as the acceptable source of service information 
for replacing the RABAB). Investigation revealed that the service 
bulletin does not specify the torque value for installing the new 
RABAB. This condition, if not corrected, could result in improper 
installation of the RABAB with consequent failure and possible collapse 
of the MLG.

Explanation of New Relevant Service Information

    Saab has issued Saab Service Bulletin 340-32-131, dated June 29, 
2004; including as Attachments 1 and 2, APPH Ltd. Service Bulletins 
AIR83022-32-28 and AIR83064-32-08, both dated January 2002; and as 
Attachments 3 and 4, APPH Ltd. Service Bulletins AIR83022-32-29 and 
AIR83064-32-09, both dated April 2002. Saab Service Bulletin 340-32-131 
supersedes Saab Service Bulletin 340-32-124, Revision 01, dated May 21, 
2002, including as Attachments 1 and 2, APPH Ltd. Service Bulletins 
AIR83022-32-28 and AIR83064-32-08, both dated January 2002; and Saab 
Service Bulletin 340-32-125, dated April 29, 2002, including as 
Attachments 1 and 2, APPH Ltd. Service Bulletins AIR83022-32-29 and 
AIR83064-32-09, both dated April 2002. Saab Service Bulletin 340-32-131 
describes procedures for replacing the RABAB with a new RABAB and 
reidentifying the MLG strut. If Service Bulletin 340-32-124, Revision 
01, has been accomplished previously, Saab Service Bulletin 340-32-131 
describes procedures for a one-time visual inspection of the new RABAB 
for corrosion, fretting, or other damage; and applicable corrective 
actions. Corrective actions could include replacing the RABAB with a 
new RABAB and repairing any other damage. Accomplishing the actions 
specified in the service information is intended to adequately address 
the unsafe condition. The LFV mandated the service information and 
issued Swedish airworthiness directive 1-195, dated July 6, 2004, to 
ensure the continued airworthiness of these airplanes in Sweden.

Comments

    Comments were submitted on the original NPRM. Due to the release of 
new service information, those comments are no longer applicable and 
are not addressed by this supplemental NPRM.

Conclusion

    Since this change expands the scope of the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.

Differences Between the Supplemental NPRM and Service Bulletin

    The service bulletin refers to a ``visual inspection'' of a 
previously replaced RABAB for corrosion, fretting, or other damage. We 
have determined that the procedures in the service bulletin should be 
described as a ``detailed inspection.'' We have included Note 2 to 
define this type of inspection.

Cost Impact

    We estimate that approximately 281 airplanes of U.S. registry would 
be affected by this proposed AD, that it would take approximately 7 
work hours per airplane to accomplish the proposed actions, and that 
the average labor rate is $65 per work hour. Required parts would be 
supplied at no cost by the manufacturer. Based on these figures, the 
cost impact of this proposed AD on U.S. operators is estimated to be 
$127,855, or $455 per airplane.
    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.

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, 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:

Saab Aircraft AB: Docket No. 2002-NM-182-AD.

    Applicability: Model SAAB SF340A series airplanes, serial 
numbers (S/Ns) 004 through 159 inclusive; and Model SAAB 340B series 
airplanes, S/Ns 160 through 459 inclusive; certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the retract actuator bracket attachment 
bolt (RABAB), which could result in loosening of the retract 
actuator bracket and consequent failure of the main landing gear 
(MLG) to retract, with considerable damage to other landing gear 
parts, including the MLG trunnion fitting, accomplish the following:

Replacement/Reidentification of RABAB

    (a) For airplanes not previously modified in accordance with 
Saab Service Bulletin 340-32-124, Revision 01, dated May 21, 2002: 
Within 12 months after the effective date of this AD, perform the 
actions specified in paragraphs (a)(1) and (a)(2) of this AD in 
accordance with the Accomplishment Instructions of Saab Service 
Bulletin 340-32-131, dated June 29, 2004, including Attachments 1 
and 2, both dated January

[[Page 57894]]

2002, and Attachments 3 and 4, both dated April 2002.

    Note 1: APPH Ltd. Service Bulletins AIR83022-32-28 and AIR83064-
32-08, both dated January 2002, comprising Attachments 1 and 2, and 
Service Bulletins AIR83022-32-29 and AIR83064-32-09, both dated 
April 2002, comprising Attachments 3 and 4, are incorporated into 
Saab Service Bulletin 340-32-131 as additional sources of service 
information.

    (1) Replace the existing RABAB with a new RABAB.
    (2) Reidentify the MLG shock strut.

Inspection of RABAB

    (b) For airplanes previously modified in accordance with Saab 
Service Bulletin 340-32-124, Revision 01, dated May 21, 2002: Within 
6 months after the effective date of this AD, perform a one-time 
detailed inspection for corrosion, fretting, or other damage of any 
RABAB replaced in accordance with Saab Service Bulletin 340-32-124, 
Revision 01; and applicable corrective actions; in accordance with 
the Accomplishment Instructions of Saab Service Bulletin 340-32-131, 
dated June 29, 2004, including Attachments 1 and 2, both dated 
January 2002, and Attachments 3 and 4, both dated April 2002.

    Note 2: For the purposes of this AD, a detailed inspection is 
``an intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirrors magnifying lenses, etc. may be necessary. Surface cleaning 
and elaborate procedures may be required.''

Parts Installation

    (c) As of the effective date of this AD, no person may install a 
RABAB, part number (P/N) AIR83022-5 through -18 inclusive, or P/N 
AIR83064 (any suffix), on any airplane.

Special Flight Permits

    (d) Special flight permits are not allowed as specified in 
section 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199).

Alternative Methods of Compliance

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

    Note 3: The subject of this AD is addressed in Swedish 
airworthiness directive 1-195, dated July 6, 2004.


    Issued in Renton, Washington, on September 20, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-21645 Filed 9-27-04; 8:45 am]

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