[Federal Register Volume 63, Number 37 (Wednesday, February 25, 1998)]
[Rules and Regulations]
[Pages 9408-9409]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-4716]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-04-AD; Amendment 39-10362; AD 98-02-51]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-300, -400, and -500 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 98-02-51 that was sent previously 
to all known U.S. owners and operators of Boeing Model 737-300, -400, 
and -500 series airplanes by individual telegrams. This AD requires a 
one-time general visual inspection to detect any missing fasteners on 
the top and bottom of the leading edge skin where it attaches to the 
front spar of the horizontal stabilizer. This AD also requires a one-
time detailed visual inspection to detect any loose or missing 
fasteners of the attachment of the elevator hinge plates to the 
horizontal stabilizer rear spar fittings. If a loose or missing 
fastener is detected, this AD requires installation of a new or 
serviceable fastener. This action is prompted by reports of loose or 
missing fasteners of the leading edge structure and elevator attachment 
fitting of the right-hand horizontal stabilizer. The actions specified 
by this AD are intended to prevent reduced structural integrity of the 
horizontal stabilizer due to loose or missing fasteners.

DATES: Effective March 2, 1998, to all persons except those persons to 
whom it was made immediately effective by telegraphic AD T98-02-51, 
issued on January 8, 1998, which contained the requirements of this 
amendment.
    Comments for inclusion in the Rules Docket must be received on or 
before April 27, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-04-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.

FOR FURTHER INFORMATION CONTACT: Gregory L. Schneider, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98055-4056; telephone (425) 227-2028 or (425) 
227-2557; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: On January 8, 1998, the FAA issued 
telegraphic AD T98-02-51, which is applicable to Boeing Model 737-300, 
-400, and -500 series airplanes.
    On December 9, 1997, a Boeing Model 737-300 series airplane 
operated by Silkair Airlines was involved in an accident after takeoff 
from Jakarta Soekarno Hatta Airport in Jakarta, Indonesia. The accident 
is under investigation by the Indonesian authorities with assistance 
from the National Transportation Safety Board (NTSB) of the United 
States, the manufacturer, the operator, and other aviation 
organizations. Although there has been no determination of the cause of 
the accident, preliminary reports from the on-site accident 
investigation indicate that the horizontal stabilizer may have 
separated from the airplane prior to impact in the Musi River. On-site 
investigation has revealed that approximately 26 fasteners were missing 
from certain leading edge structure on the right-hand (RH) horizontal 
stabilizer (12 from the upper surface, and 14 from the lower surface). 
Additionally, early reports indicated that at least one fastener may 
have been missing from an elevator attachment fitting in an outboard 
section of the RH horizontal stabilizer.
    Subsequently, there has been a report of evidence that the fastener 
was actually installed. However, the FAA has received a report that an 
operator found one loose fastener during inspection of an in-service 
airplane. (There have been no reports to date of any fasteners missing 
from the left-hand (LH) horizontal stabilizer.)
    There is, as of yet, no evidence linking these missing or loose 
fasteners to the cause of the accident.
    Loose or missing fasteners on the LH or RH horizontal stabilizer 
could reduce the structural integrity of the horizontal stabilizer.
    Because the airplane had been placed in service a relatively short 
time ago (February 14, 1997), it is possible that the fasteners were 
missing because they had not been installed during manufacture. If such 
a quality control failure occurred on this airplane, it may also have 
occurred on others produced at approximately the same time.

Explanation of Requirements of the Rule

    Since the unsafe condition described is likely to exist or develop 
on other airplanes of the same type design, the FAA issued telegraphic 
AD T98-02-51 to require a one-time general visual inspection to detect 
any missing fasteners on the top and bottom of the leading edge skin 
where it attaches to the front spar of the horizontal stabilizer.
    This AD also requires a one-time detailed visual inspection to 
detect any loose or missing fasteners of the attachment of the elevator 
hinge plates to the horizontal stabilizer rear spar fittings. If a 
loose or missing fastener is detected, this AD requires installation of 
a new or serviceable fastener.
    In addition, this AD requires that operators submit a report of all 
inspection findings to the FAA. Since the cause of the missing 
fasteners of the LH and RH horizontal stabilizer is currently unknown, 
the intent of the required reports is to enable the FAA to determine 
how widespread such discrepancies may be in the affected fleet. Because 
the investigation is continuing, further action may be necessary. This 
is considered to be interim action until final action is identified, at 
which time the FAA may consider further rulemaking.

Publication and Effectivity of AD

    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual telegrams 
issued on January 8, 1998, to all known U.S. owners and operators of 
certain Boeing Model 737-300, -400, and -500 series airplanes. These 
conditions still exist, and the AD is hereby published in the Federal 
Register as an amendment to section 39.13 of the Federal Aviation 
Regulations (14 CFR 39.13) to make it effective to all persons.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire.

[[Page 9409]]

Communications shall identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-NM-04-AD.'' The postcard will be date stamped and 
returned to the commenter.

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.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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, 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 adding the following new 
airworthiness directive:
98-02-51  Boeing: Amendment 39-10362. Docket 98-NM-04-AD.

    Applicability: Model 737-300, -400, and -500 series airplanes 
having line positions 2765 through 2977 inclusive; certificated in 
any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
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 (e) 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.
    To prevent reduced structural integrity of the horizontal 
stabilizer due to loose or missing fasteners of the left- or right-
hand horizontal stabilizer, accomplish the following:
    (a) Within 5 flight cycles or 24 clock hours after the effective 
date of this AD, whichever occurs later, perform the following 
inspections of the left- and right-hand sides of the horizontal 
stabilizer:
    (1) Perform a general visual inspection to determine if any 
fasteners are missing on the top and bottom of the leading edge skin 
where it is attached to the front spar.
    (2) Perform a detailed visual inspection to detect loose or 
missing fasteners of the attachment of the elevator hinge plates to 
the left- and right-hand sides of the horizontal stabilizer rear 
spar fittings. Ensure torque sealant has not been broken on the 
fasteners.
    (b) If no discrepancies are found, no further inspections are 
required by this AD.
    (c) If any fastener is loose or missing, or if the torque 
sealant has been broken on any fastener, prior to further flight, 
install a new or serviceable fastener.
    (d) Within 5 days after accomplishing the inspections required 
by this AD, report inspection results, positive or negative, to the 
Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056; fax (425) 227-1181. Information collection requirements 
contained in this regulation have been approved by the Office of 
Management and Budget (OMB) under the provisions of the paperwork 
reduction act of 1980 (44 U.S.C. 3501 et seq.) have been assigned 
OMB control number 2120-0056.
    (e) 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, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Manager, Seattle ACO.

    (f) 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.
    (g) This amendment becomes effective on March 2, 1998, to all 
persons except those persons to whom it was made immediately 
effective by telegraphic AD T98-02-51, issued on January 8, 1998, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on February 18, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-4716 Filed 2-24-98; 8:45 am]
BILLING CODE 4910-13-U