[Federal Register Volume 59, Number 249 (Thursday, December 29, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-32035]


[[Page Unknown]]

[Federal Register: December 29, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-179-AD]

 

Airworthiness Directives; Boeing Model 727 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Boeing Model 727 
series airplanes, that currently requires repetitive visual inspections 
to detect cracks of the elevator rear spar, and repair, if necessary. 
It also provides for a terminating action for the repetitive 
inspections. This action would add a one-time inspection to verify that 
proper clearance exists between the shear plate and the radii of the 
elevator rear spar on airplanes on which the terminating action has 
been accomplished. This proposal would also provide for an improved 
terminating action. This proposal is prompted by reports of cracking in 
the spar radii at the tab hinge location of the elevator rear spar on 
certain airplanes. The actions specified by the proposed AD are 
intended to prevent such cracking, which could result in excessive free 
play of the elevator control tab and possible tab flutter.

DATES: Comments must be received by February 27, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-179-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Walter Sippel, Aerospace Engineer, 
Airframe Branch, ANM-121S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (206) 227-2774; fax (206) 227-1181.

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 notice may be changed in 
light of the comments received.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 94-NM-179-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-103, Attention: Rules 
Docket No. 94-NM-179-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion -

    On October 31, 1984, the FAA issued AD 84-22-02, amendment 39-4951 
(49 FR 45743, November 20, 1984), applicable to certain Boeing Model 
727 series airplanes, to require repetitive visual inspections to 
detect cracks of the elevator rear spar, and repair, if necessary. That 
action was prompted by several reports of cracking in the rear spar 
flange radii at the elevator tab hinge points. The requirements of that 
AD are intended to prevent cracking in the elevator rear spar, which 
could result in excessive free play of the elevator control tab and 
possible tab flutter.
    Since the issuance of that AD, there have been several reports of 
cracking in the spar radii at the tab hinge location of the elevator 
rear spar on airplanes that were modified in accordance with Boeing 
Service Bulletin 727-55-0085, dated August 31, 1984. That modification 
was considered to be terminating action for the repetitive inspection 
requirements of AD 84-22-02. The manufacturer has advised that the 
cause of this cracking has been attributed to continued contact between 
the shear plate and the radii of the elevator rear spar. Cracking in 
this area, if not corrected, could result in excessive free play of the 
elevator control tab and possible tab flutter.
    The FAA has reviewed and approved Boeing Service Bulletin 727-55-
0085, Revision 4, dated March 31, 1994, which describes procedures for 
continued repetitive visual inspections to detect cracks of the 
elevator rear spar, and repair, if necessary. For airplanes that have 
been modified in accordance with previous revisions of Boeing Service 
Bulletin 727-55-0085, the service bulletin describes procedures for an 
additional one-time inspection to verify that proper clearance exists 
between the shear plate and the radii of the elevator rear spar, and 
repair, if necessary. Additionally, for all other airplanes, the 
service bulletin provides instructions for accomplishing an improved 
modification or repair that would eliminate the need for the repetitive 
inspections.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 84-22-02 to continue to require 
repetitive visual inspections to detect cracks of the elevator rear 
spar, and repair, if necessary. However, this proposal would add a one-
time inspection to verify that proper clearance exists between the 
shear plate and the radii of the elevator rear spar on airplanes on 
which the terminating action specified in AD 84-22-02 has been 
accomplished. The proposed AD would also provide for an improved 
modification or repair of the elevator rear spar, which, if 
accomplished, would constitute terminating action for the repetitive 
visual inspection requirements. The actions would be required to be 
accomplished in accordance with the service bulletin described 
previously.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this requirement.
    There are approximately 100 Model 727 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 64 
airplanes of U.S. registry would be affected by this proposed AD.
    The inspections of the elevator rear spar that were previously 
required by AD 84-22-02, and retained in this proposal, take 
approximately 12 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the total cost 
impact of this currently-required inspection requirement on U.S. 
operators is estimated to be $46,080, or $720 per airplane, per 
inspection cycle.
    The one-time inspection of previously modified airplanes that would 
be required by this proposal would take approximately 12 work hours per 
airplane to accomplish, at an average labor rate of $60 per work hour. 
Based on these figures, the total cost impact of the one-time 
inspection requirement of this proposal on U.S. operators of previously 
modified airplanes is estimated to be $720 per airplane.
    The total cost impact figures, discussed above, are based on 
assumptions that no operator has yet accomplished the current or 
proposed requirements of this AD action, and that no operator would 
accomplish those actions in the future if this AD were not adopted.
    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-4951 (49 FR 
45743, November 20, 1984), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 94-NM-179-AD. Supersedes AD 84-22-02, Amendment 39-
4951.

    Applicability: Model 727 series airplanes, line numbers 1720 
through 1831 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 use the authority 
provided in paragraph (e) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent excessive free play of the elevator control tab and 
possible tab flutter, accomplish the following:
    (a) For airplanes on which the modification described in Boeing 
Service Bulletin 727-55-0085, dated August 31, 1984 (specified as 
terminating action in AD 84-22-02, amendment 39-4951), has not been 
accomplished: Within the next 300 flight hours after November 20, 
1984 (the effective date of AD 84-22-02, amendment 4951), or prior 
to the accumulation of 8,000 total flight hours, whichever occurs 
later, perform a visual inspection to detect cracks of the elevator 
rear spar, in accordance with Boeing Service Bulletin 727-55-0085, 
dated August 31, 1984; Revision 1, dated November 16, 1984; Revision 
2, dated December 21, 1984; Revision 3, dated July 26, 1985; or 
Revision 4, dated March 31, 1994. Repeat the inspection thereafter 
at intervals not to exceed 1,600 flight hours. After the effective 
date of this AD, only Revision 4 of this service bulletin shall be 
used.
    (b) If any crack is found during any inspection required by 
paragraph (a) of this AD, accomplish paragraphs (b)(1) and (b)(2) of 
this AD in accordance with Boeing Service Bulletin 727-55-0085, 
dated August 31, 1984; Revision 1, dated November 16, 1984; Revision 
2, dated December 21, 1984; Revision 3, dated July 26, 1985; or 
Revision 4, dated March 31, 1994. After the effective date of this 
AD, only Revision 4 of this service bulletin shall be used.
    (1) If any crack is found that is within the limits specified in 
Part 1 of the Accomplishment Instructions of the service bulletin, 
accomplish paragraphs (b)(1)(i) and (b)(1)(ii) of this AD.
    (i) Prior to further flight, perform a time-limited repair by 
stop drilling the crack in accordance with the service bulletin. 
Within 1,600 flight hours after the repair, repeat the inspection 
required by paragraph (a) of this AD.
    (ii) Prior to the accumulation of 3,200 flight hours after stop 
drilling the crack, repair the elevator rear spar in accordance with 
Part III of the Accomplishment Instructions of the service bulletin.
    (2) If any crack is found that is outside the limits specified 
in Part 1 of the Accomplishment Instructions of the service 
bulletin, prior to further flight, repair the elevator rear spar in 
accordance with Part III of the Accomplishment Instructions of the 
service bulletin.
    (c) For airplanes on which the modification specified in Boeing 
Service Bulletin 727-55-0085, dated August 13, 1984 (specified as 
terminating action in AD 84-22-02, amendment 39-4951), has been 
accomplished: Prior to the accumulation of 1,600 flight hours, or 
within 12 months after the effective date of this AD, whichever 
occurs later, perform an inspection to verify that proper clearance 
exists between the shear plate and the radii of the elevator rear 
spar, in accordance with Boeing Service Bulletin 727-55-0085, 
Revision 4, dated March 31, 1994.
    (1) If the clearance is within the limits specified in Part 1 of 
the Accomplishment Instructions of the service bulletin, no further 
action is required by this AD.
    (2) If the clearance is outside the limits specified in Part 1 
of the Accomplishment Instructions in the service bulletin, prior to 
further flight, reaccomplish the modification in accordance with 
Revision 4 of the service bulletin. After modification, no further 
action is required by this AD.
    (d) Modification or repair of the elevator rear spar, in 
accordance with Part II or Part III of the Accomplishment 
Instructions of Boeing Service Bulletin 727-55-0085, Revision 4, 
dated March 31, 1994, constitutes terminating action for the 
requirements of this AD.
    (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 Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate. 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 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.

    Issued in Renton, Washington, on December 22, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-32035 Filed 12-28-94; 8:45 am]
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