[Federal Register Volume 69, Number 113 (Monday, June 14, 2004)]
[Proposed Rules]
[Pages 32922-32924]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-13223]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-178-AD]
RIN 2120-AA64


Airworthiness Directives; Short Brothers Model SD3 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Short Brothers Model SD3 
series airplanes. This proposal would require testing for stiffness of 
the aft pintle pin bushing of the main landing gear (MLG), and 
inspecting and measuring the aft pintle pin bushings of the MLG for 
damage, and for out-of-limit dimensions of the bushing bore. This 
proposal would also require corrective action if necessary. This action 
is necessary to detect and correct corrosion and deterioration of the 
aft pintle pin bushings of the MLG. Corrosion and deterioration of the 
bushings, if not detected and corrected, could result in the MLG not 
extending fully during landing, with consequent damage to the airplane 
structure. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by July 14, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-178-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: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2003-NM-178-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 Short Brothers, Airworthiness & Engineering Quality, P.O. 
Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. This 
information may be examined at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; 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

[[Page 32923]]

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 2003-NM-178-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. 2003-NM-178-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, notified the FAA that an unsafe 
condition may exist on all Short Brothers Model SD3 series airplanes. 
The CAA advises that the main landing gear (MLG) on one Short Brothers 
Model SD3-30 series airplane failed to extend fully and lock. This 
failure resulted from deterioration and corrosion of the aft pintle pin 
bushings of the MLG. In addition, the CAA reports that there continues 
to be a high frequency of problems with the MLG, which may be 
associated with deterioration of the aft pintle pin bushings. 
Deterioration and corrosion of the aft pintle pin bushings of the MLG, 
if not corrected, could result in the MLG not extending fully during 
landing, with consequent damage to the airplane structure.
    The subject area on Short Brothers Model SD3-30 series airplanes is 
almost identical to that on the other Short Brothers Model SD3 series 
airplanes. Therefore, all Shorts Model SD3 series airplanes may be 
subject to the unsafe condition revealed on Model SD3-30 series 
airplanes.

Explanation of Relevant Service Information

    Short Brothers has issued the following service bulletins:
     For Model SD3-30 series airplanes: Service Bulletin SD330-
32-122, dated April 30, 2003;
     For Model SD3 SHERPA series airplanes: Service Bulletin 
SD3 SHERPA-32-3, dated April 30, 2003;
     For Model SD3-60 SHERPA series airplanes: Service Bulletin 
SD360 SHERPA-32-2, dated April 30, 2003; and
     For Model SD3-60 series airplanes: Service Bulletin SD360-
32-36, Revision 1, dated May 26, 2003. This service bulletin references 
Short Brothers Service Bulletin SD360-32-03, dated November 1983, as an 
additional source of service information for replacement of certain 
bushings, if necessary.
    These service bulletins describe the following procedures related 
to the aft pintle pin bushings of the MLG:
     Doing friction tests for stiffness of the aft pintle pin 
bushings, and sending results of the tests to the manufacturer;
     Performing a detailed inspection for defects (corrosion or 
deterioration) of the bushings;
     Measuring the bore diameter, in three locations, of each 
of the three bushings to determine if the dimensions are outside 
specified limits;
     Taking corrective action if there is any defect in a 
bushing or if the bore dimension is outside specified limits (the 
corrective action is replacing the bushing with a new improved bushing 
having a new part number, and refitting the bushing); and
     Doing other significant actions such as refitting new 
bushings and any bushings that were removed during inspection, but not 
replaced; and doing a functional test of the MLG extension and 
retraction function.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. The CAA 
classified these service bulletins as mandatory and issued British 
airworthiness directives 001-04-2003 (for Model SD3-30 series 
airplanes), 002-04-2003 (for Model SD3-60 series airplanes), 004-04-
2003 (for Model SD3 SHERPA series airplanes), and 003-04-2003 (for 
Model SD3-60 SHERPA series airplanes), to ensure the continued 
airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

    These airplane models are manufactured in the United Kingdom and 
are type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept us informed 
of the situation described above. We have examined the findings of the 
CAA, reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the applicable service bulletin described 
previously, except as discussed below.

Difference Between the Proposed Rule and the Service Bulletins

    Operators should note that, although the service bulletins describe 
procedures for sending certain information and items to the 
manufacturer (i.e., results of the friction tests, unserviceable 
bushings, and photographs of serviceable bushings), this proposed rule 
does not include that requirement.

Interim Action

    We consider this proposed AD interim action. If final action is 
later identified, we may consider further rulemaking then.

Cost Impact

    We estimate that 108 airplanes of U.S. registry would be affected 
by this proposed AD, that it would take approximately 30 work hours per 
airplane to accomplish the proposed test, inspection, and measurement, 
and that the average labor rate is $65 per work hour. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $210,600, or $1,950 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

[[Page 32924]]

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:

Short Brothers PLC: Docket 2003-NM-178-AD.

    Applicability: All Short Brothers Model SD3 series airplanes, 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct corrosion and deterioration of the aft 
pintle pin bushings of the main landing gear (MLG), which could 
result in the MLG not extending fully during landing, with 
consequent damage to the airplane structure, accomplish the 
following:

Service Bulletin Reference

    (a) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of the following service bulletins, as 
applicable:
    (1) For Model SD3-30 series airplanes: Short Brothers Service 
Bulletin SD330-32-122, dated April 30, 2003.
    (2) For Model SD3 SHERPA series airplanes: Short Brothers 
Service Bulletin SD3 SHERPA-32-3, dated April 30, 2003.
    (3) For Model SD3-60 SHERPA series airplanes: Short Brothers 
Service Bulletin SD360 SHERPA-32-2, dated April 30, 2003.
    (4) For Model SD3-60 series airplanes: Short Brothers Service 
Bulletin SD3-60-32-36, Revision 1, dated May 26, 2003.

    Note 1: Short Brothers Service Bulletin SD3-60-32-36 references 
Short Brothers Service Bulletin SD360-32-03, dated November 1983, as 
an additional source of service information for replacement of 
certain bushings, if necessary.

Tests, Inspection, Measurements, and Corrective Action

    (b) Within 24 months after the effective date of this AD: Do a 
friction test for stiffness of the aft pintle pin bushings of the 
MLG, and a detailed inspection for any defect of the bushings of the 
aft pintle pin of the MLG; and measure the bore diameter of the 
bushings (if a defect is found, this paragraph requires that the 
bushing be replaced; therefore, it is not necessary to do the bore 
diameter measurement on that bushing). Do all applicable corrective 
actions and other specified actions prior to further flight. Do all 
actions per the applicable service bulletin.

    Note 2: 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.''

No Reporting Requirement

    (c) Although the service bulletins specify to send certain items 
to Short Brothers for evaluation (i.e., results of the friction 
tests, unserviceable bushings, and photographs of serviceable 
bushings), this AD does not require that action.

Alternative Methods of Compliance

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

    Note 3: The subject of this AD is addressed in British 
airworthiness directives 001-04-2003 (for Model SD3-30 series 
airplanes), 002-04-2003 (for Model SD3-60 series airplanes), 004-04-
2003 (for Model SD3 SHERPA series airplanes), and 003-04-2003 (for 
Model SD3-60 SHERPA series airplanes).


    Issued in Renton, Washington, on June 3, 2004.
Franklin Tiangsing,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-13223 Filed 6-10-04; 8:45 am]
BILLING CODE 4910-13-P