[Federal Register Volume 69, Number 78 (Thursday, April 22, 2004)]
[Proposed Rules]
[Pages 21766-21768]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-9110]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 69, No. 78 / Thursday, April 22, 2004 / 
Proposed Rules  

[[Page 21766]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-236-AD]
RIN 2120-AA64


Airworthiness Directives; Short Brothers Model SD3-60 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 SD3-60 
series airplanes. This proposal would require inspection of the welded 
joints of the balance weight brackets for the left and right elevator 
trim tabs for cracking; repetitive inspections, as applicable; and 
corrective actions including the eventual replacement of all brackets, 
which would constitute terminating action for the repetitive 
inspections. This action is necessary to prevent the loss of the 
balance weight for the elevator trim tab, which could result in 
incorrect trim during takeoff and landing, and reduced controllability 
of the airplane. This action is intended to address the identified 
unsafe condition.

DATES: Comments must be received by May 24, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-236-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-236-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 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-236-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-236-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 SD3-60 series 
airplanes. The CAA advises that, on one affected airplane, the balance 
weight assembly for an elevator trim tab detached during landing. 
Subsequent investigation showed that the failure was caused by fatigue 
cracking emanating from the weld of the balance weight bracket. This 
condition, if not corrected, could result in the loss of the balance 
weight for the elevator trim tab, which could cause incorrect trim 
during takeoff and landing, and reduced controllability of the 
airplane.

Explanation of Relevant Service Information

    Shorts has issued Short Brothers Service Bulletin SD360-55-20, 
dated June 26, 2003, which describes procedures for performing a dye 
penetrant inspection for cracking in the welded joints of the balance 
weight brackets for the left and right elevator trim tabs. Depending on 
the results of the dye penetrant inspection, the total number of flight 
hours accumulated on the airplane and/or the brackets, and the length 
of any crack, the service bulletin describes procedures for further 
investigative and corrective actions. These investigative and 
corrective actions include refitting the balance weights, performing 
repetitive inspections, repairing the bracket (including a further dye 
penetrant inspection), and/or replacing the bracket with a new or 
serviceable bracket, as

[[Page 21767]]

applicable. The service bulletin gives compliance times for eventual 
replacement of all brackets when they reach their life limits. This 
service bulletin permits further flight with brackets having a cracked 
welded joint, within certain limits.
    Accomplishment of the actions specified in the service bulletin is 
intended to adequately address the identified unsafe condition. The CAA 
classified this service bulletin as mandatory and issued British 
airworthiness directive 009-06-2003 to ensure the continued 
airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of Sec.  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 the FAA 
informed of the situation described above. The FAA has 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 service bulletin described previously, 
except as discussed below.

Differences Between the Proposed AD and the Service Bulletin

    Unlike the procedures described in Short Brothers Service Bulletin 
SD360-55-20, dated June 26, 2003, this proposed AD would not permit 
further flight if cracks of any length are detected in the welded 
joints of the balance weight brackets. We have determined that, because 
of the safety implications and consequences associated with such 
cracking, any bracket with a cracked welded joint must be repaired or 
replaced before further flight.
    The service bulletin specifies that operators may contact the 
manufacturer for disposition of certain conditions when refitting 
balance weights; in those conditions; however, this proposed AD would 
require operators to obtain further disposition instructions from the 
FAA or the CAA (or its delegated agent).

Cost Impact

    The FAA estimates that 42 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 12 work 
hours per airplane to accomplish the proposed inspections, and that the 
average labor rate is $65 per work hour. Based on these figures, the 
cost impact of this proposed action on U.S. operators is estimated to 
be $32,760, or $780 per airplane, per inspection cycle.
    It would take approximately 8 hours per airplane to accomplish the 
proposed replacement of the brackets. Required parts would cost 
approximately $632 per airplane. Based on these figures, the cost 
impact of this proposed action on U.S. operators is estimated to be 
$48,384, or $1,152 per airplane.
    The cost impact figures discussed above are 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:

Short Brothers PLC: Docket 2003-NM-236-AD.

    Applicability: All Model SD3-60 series airplanes, certificated 
in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the loss of the balance weight for the elevator trim 
tab, which could result in incorrect trim during takeoff and 
landing, and reduced controllability of the airplane, accomplish the 
following:

Service Bulletin Reference

    (a) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Short Brothers Service Bulletin 
SD360-55-20, dated June 26, 2003.

Initial Inspection

    (b) Within 2 months after the effective date of this AD: Do a 
dye penetrant inspection for cracking in the welded joints of the 
balance weight brackets for the left and right elevator trim tabs, 
in accordance with the service bulletin.

Investigative and Corrective Actions if No Cracking Is Found

    (c) If no cracking is found during the inspection required by 
paragraph (b) of this AD, do the actions required by paragraphs 
(c)(1) and (c)(2) of this AD at the applicable compliance times.
    (1) Repeat the inspection required by paragraph (b) of this AD 
at intervals not to exceed 4,800 flight hours until the bracket is 
replaced per paragraph (c)(2) or (d) of this AD.
    (2) Prior to the accumulation of 28,800 total flight hours, or 
within 6 months after the effective date of this AD, whichever 
occurs later: Replace any bracket that has not been replaced per 
paragraph (d) of this AD with a new bracket or with a serviceable 
bracket that has been inspected in accordance with paragraph (b) of 
this AD. Replace in accordance with the service bulletin. 
Replacement of the brackets constitutes terminating action for the 
repetitive inspections required by paragraph (c)(1) of this AD.

[[Page 21768]]

Corrective Actions if Any Crack Is Found

    (d) If any crack is found during any inspection required by 
paragraph (b) or (c) of this AD: Before further flight, accomplish 
the applicable action in paragraph (d)(1) or (d)(2) of this AD in 
accordance with the service bulletin.
    (1) For airplanes that have accumulated less than 28,800 flight 
hours and on which all cracks on brackets are less than 0.25 inch in 
length: Repair the affected bracket in accordance with Part B of the 
service bulletin (including the additional dye penetrant inspection 
of the repaired welded joint) and repeat the inspection required by 
paragraph (b) of this AD at intervals not to exceed 4,800 flight 
hours; or replace the bracket in accordance with paragraph (d)(2) of 
this AD. Replacement of the bracket constitutes terminating action 
for the repetitive inspections.
    (2) For any airplane on which any crack on a bracket is 0.25 
inch in length or greater, and for any airplane that has accumulated 
28,800 flight hours or more on which any crack of any length is 
found on a bracket: Replace the affected bracket with a new bracket 
or with a serviceable bracket that has been inspected in accordance 
with paragraph (b) of this AD. Replacement of the bracket 
constitutes terminating action for the repetitive inspections 
required by paragraph (d)(1) of this AD.

Refitting

    (e) Before further flight following any inspection per 
paragraphs (b) or (c) of this AD; or before further flight following 
repair or replacement of a bracket per paragraphs (c)(2) or (d) of 
this AD: Refit the balance weights, covers, and trim tabs, in 
accordance with the service bulletin. Where the service bulletin 
specifies to contact the manufacturer for disposition of certain 
conditions while refitting, obtain further disposition instructions 
from the Manager, International Branch, ANM-116, FAA, Transport 
Airplane Directorate; or the Civil Aviation Authority (CAA) (or its 
delegated agent).

Parts Installation

    (f) As of the effective date of this AD, no person may install 
on any airplane a balance weight bracket unless the welded joint has 
been inspected in accordance with paragraph (b) of this AD.

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.

    Note 1: The subject of this AD is addressed in British 
airworthiness directive 009-06-2003.


    Issued in Renton, Washington, on April 15, 2004.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-9110 Filed 4-21-04; 8:45 am]
BILLING CODE 4910-13-P