AD 2001-23-01

[Federal Register Volume 66, Number 220 (Wednesday, November 14, 2001)]
[Rules and Regulations]
[Pages 56989-56991]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-28295]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-20-AD; Amendment 39-12498; AD 2001-23-01]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-600, -700, and -800 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain Boeing Model 737-600, -700, and -800 series 
airplanes, that currently requires repetitive inspections of certain 
elevator hinge plates, and corrective action, if necessary. That AD 
also provides for an optional replacement of the elevator hinge plates 
with new, improved hinge plates, which would end the repetitive 
inspections. This amendment requires accomplishment of the previously 
optional replacement of the elevator hinge plates with new, improved 
hinge plates, as terminating action for the repetitive inspections. The 
actions specified by this AD are intended to

[[Page 56990]]

prevent fatigue cracking of the elevator hinge plates, which could lead 
to the loss of the attachment of the elevator to the horizontal 
stabilizer, and consequent reduced controllability of the airplane. 
This action is intended to address the identified unsafe condition.

DATES: Effective December 19, 2001.
    The incorporation by reference of certain publications listed in 
the regulations was approved previously by the Director of the Federal 
Register as of April 9, 2001 (66 FR 16116, March 23, 2001).

ADDRESSES: The service information referenced in this AD may be 
obtained from 2001-NM-20-AD. 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 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Nancy Marsh, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2028; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 2001-06-08, 
amendment 39-12155 (66 FR 16116, March 23, 2001); which is applicable 
to certain Boeing Model 737-600, -700, and -800 series airplanes; was 
published in the Federal Register on June 29, 2001 (66 FR 34591). The 
action proposed to continue to require repetitive inspections of 
certain elevator hinge plates, and corrective action, if necessary. 
That AD also provides for an optional replacement of the elevator hinge 
plates with new, improved hinge plates, which would end the repetitive 
inspections. This AD requires accomplishment of the previously optional 
replacement of the elevator hinge plates with new, improved hinge 
plates, as terminating action for the repetitive inspections.

Comment

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

Extend Compliance Time

    The commenter asks that the compliance time of ``Before the 
accumulation of 15,000 total flight cycles, or within 5 years since the 
airplane's date of manufacture, whichever occurs first,'' as specified 
in paragraph (b) of the proposed rule, be extended to whichever occurs 
later. The commenter states that this change will result in an 
acceptable level of safety, and allow operators to accomplish the work 
within existing maintenance visits.
    The FAA does not agree with the commenter's request to extend the 
compliance time for the hinge replacement required by paragraph (b) of 
the final rule. With regard to extending the compliance time to allow 
the replacement to be accomplished within existing maintenance visits, 
we have considered factors such as operators' maintenance schedules in 
setting a compliance time for the required replacement. We have 
determined the compliance time specified in paragraph (b) of the final 
rule is an appropriate compliance time in which the replacement may be 
accomplished during scheduled airplane maintenance for the majority of 
affected operators. Since maintenance schedules vary from operator to 
operator, it would not be possible to guarantee that all affected 
airplanes could be modified during scheduled maintenance. Therefore, we 
find the compliance time represents the maximum time wherein the 
affected airplanes may continue to operate without compromising safety. 
No change to the final rule is necessary.

Conclusion

    The FAA has determined that air safety and the public interest 
require the adoption of the rule as proposed.

Cost Impact

    There are approximately 84 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 39 airplanes of U.S. registry 
will be affected by this AD.
    The inspections that are currently required by AD 2001-06-08 take 
approximately 4 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the currently required actions on U.S. operators is estimated 
to be $9,360, or $240 per airplane, per inspection cycle.
    The new replacement that is required by this AD action will take 
approximately 44 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Required parts will cost approximately 
$13,116 per airplane. Based on these figures, the cost impact of the 
requirements of this AD on U.S. operators is estimated to be $614,484, 
or $15,756 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.

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

    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 removing amendment 39-12155 (66 FR

[[Page 56991]]

16116, March 23, 2001), and by adding a new airworthiness directive 
(AD), amendment 39-12498, to read as follows:

2001-23-01  Boeing: Amendment 39-12498. Docket 2001-NM-20-AD. 
Supersedes AD 2001-06-08, Amendment 39-12155.

    Applicability: Model 737-600, -700, and -800 series airplanes; 
line numbers 1 through 84 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 (d) 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 fatigue cracking of the elevator hinge plates, which 
could lead to the loss of the attachment of the elevator to the 
horizontal stabilizer, and consequent reduced controllability of the 
airplane, accomplish the following:

Restatement of Requirements of AD 2001-06-08

Inspections and Corrective Actions

    (a) Prior to the accumulation of 7,000 total flight cycles or 
within 90 days after April 9, 2001 (the effective date of AD 2001-
06-08), whichever occurs later, perform high frequency eddy current 
and detailed visual inspections of the hinge plate at elevator hinge 
4, and a detailed visual inspection of the elevator hinge plate lugs 
(three locations) at elevator hinges 3, 5, 6, 7, and 8. Do these 
inspections per Part I of the Accomplishment Instructions of Boeing 
Service Bulletin 737-55-1067, dated October 19, 2000. Repeat the 
inspections thereafter no later than every 4,000 flight cycles, per 
the service bulletin, until paragraph (b) of this AD has been 
accomplished. If any cracking or unusual wear (i.e., elongated 
holes, loose or missing nuts or bolts, or missing primer or finish) 
is found during any inspection per this paragraph, before further 
flight, replace the affected hinge plate with a new, improved hinge 
plate, and modify the elevator upper skin, the upper and lower hinge 
covers, and the upper and lower closure panels, as applicable, per 
the service bulletin, except as provided by paragraph (c) of this 
AD. Such replacement and modification ends the repetitive 
inspections for the replaced hinge plate.

    Note 2: For the purposes of this AD, a detailed visual 
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.''

New Requirements of This AD

Replacement of Hinge Plates

    (b) Before the accumulation of 15,000 total flight cycles, or 
within 5 years since the airplane's date of manufacture, whichever 
occurs first: Replace the elevator hinge plates at hinges 3, 4, 5, 
6, 7, and 8, with new, improved hinge plates; per Part II of the 
Accomplishment Instructions of Boeing Service Bulletin 737-55-1067, 
dated October 19, 2000, except as provided by paragraph (c) of this 
AD. The replacement includes modification of the elevator upper 
skin, the upper and lower hinge covers, and the upper and lower 
closure panels, as applicable. Doing this replacement ends the 
repetitive inspections required by this AD.

Exception to Service Bulletin Instructions: Wear Limits

    (c) During the replacement of elevator hinge plates per 
paragraph (a) or (b) of this AD, where Boeing Service Bulletin 737-
55-1067, dated October 19, 2000, specifies to contact Boeing for 
wear limits, before further flight, contact the Manager, Seattle 
Aircraft Certification Office (ACO), FAA, or a Boeing Company 
Designated Engineering Representative who has been authorized by the 
Manager, Seattle ACO, to make such findings. For wear limits to be 
approved by the Manager, Seattle ACO, as required by this paragraph, 
the Manager's approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (d) 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 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (e) 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.

Incorporation by Reference

    (f) Except as provided by paragraph (c) of this AD, the actions 
shall be done in accordance with Boeing Service Bulletin 737-55-
1067, dated October 19, 2000. This incorporation by reference was 
approved previously by the Director of the Federal Register as of 
April 9, 2001 (66 FR 16116, March 23, 2001). Copies may be obtained 
from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 
at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.

Effective Date

    (g) This amendment becomes effective on December 19, 2001.

    Issued in Renton, Washington, on November 5, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.

[FR Doc. 01-28295 Filed 11-13-01; 8:45 am]
BILLING CODE 4910-13-P