[Federal Register Volume 64, Number 4 (Thursday, January 7, 1999)]
[Rules and Regulations]
[Pages 987-989]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-184]
[[Page 987]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-NM-264-AD; Amendment 39-10984; AD 98-11-04 R1]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100 and -200 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; correction.
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SUMMARY: This amendment corrects information in an existing
airworthiness directive (AD), applicable to all Boeing Model 737-100
and -200 series airplanes, that currently requires that the FAA-
approved maintenance inspection program be revised to include
inspections that will give no less than the required damage tolerance
rating for each Structural Significant Item, and repair of cracked
structure. The actions specified in that AD are intended to ensure the
continued structural integrity of the entire Boeing Model 737-100 and -
200 fleet. This amendment corrects the requirements of the current AD
by allowing operators not to change their programs if they determine
that the existing inspections are effective for the new or affected
SSI. This amendment is prompted by a review of the requirements of the
existing AD.
DATES: Effective June 23, 1998.
The incorporation by reference of certain publications listed in
the regulations was approved previously by the Director of the Federal
Register as of June 23, 1998 (63 FR 27465, May 19, 1998).
FOR FURTHER INFORMATION CONTACT: Greg Schneider, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Washington; telephone (425) 227-2028; fax (425)
227-1181.
SUPPLEMENTARY INFORMATION: On May 12, 1998, the FAA issued AD 98-11-04,
amendment 39-10531 (63 FR 27465, May 19, 1998), which is applicable to
all Boeing Model 737-100 and -200 series airplanes. That AD requires
that the FAA-approved maintenance inspection program be revised to
include inspections that will give no less than the required damage
tolerance rating for each Structural Significant Item (SSI), and repair
of cracked structure. That action was prompted by a structural re-
evaluation by the manufacturer which identified additional structural
elements where, if damage were to occur, supplemental inspections may
be required for timely detection. The actions required by that AD are
intended to ensure the continued structural integrity of the entire
Boeing Model 737-100 and -200 fleet.
AD 98-11-04 contains provisions regarding when operators must
revise their maintenance or inspection program to address SSI's that
are created or affected by repairs and design changes. As discussed in
the preamble to the final rule, the FAA intended that such revisions be
made only if a damage tolerance assessment indicates that such a change
is necessary because existing inspections are ineffective for the SSI.
Paragraph (d)(1) of the AD, applicable to repairs and design changes
accomplished prior to the effective date of the AD, properly states the
FAA's intent. However, the FAA inadvertently omitted a comparable
provision in paragraph (g), which applies to repairs and design changes
accomplished after the effective date of the AD. As adopted, paragraph
(g) requires that operators revise their maintenance programs following
repairs and design changes, regardless of whether a damage tolerance
assessment indicates that the existing applicable inspection continue
to be effective. Therefore, consistent with the FAA's intent, this
correction is necessary to allow operators not to change their programs
if they determine that the existing inspections are effective for the
new or affected SSI.
Action is taken herein to correct these requirements of AD 98-11-04
and to correctly add the AD as an amendment to section 39.13 of the
Federal Aviation Regulations (14 CFR 39.13).
The final rule is being reprinted in its entirety for the
convenience of affected operators. The effective date remains June 23,
1998.
Since this action only corrects a current requirement, it has no
adverse economic impact and imposes no additional burden on any person.
Therefore, notice and public procedures hereon are unnecessary.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Correction
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 39-10531 (63 FR
27465, May 19, 1998), and by adding a new airworthiness directive (AD),
amendment 39-10984, to read as follows:
98-11-04 R1 Boeing: Amendment 39-10984. Docket 96-NM-264-AD.
Revises AD 98-11-04, Amendment 39-10531.
Applicability: All Model 737-100 and -200 series airplanes
(including Model 737-200C series airplanes), certificated in any
category.
Compliance: Required as indicated, unless accomplished
previously.
To ensure the continued structural integrity of the entire
Boeing Model 737-100 and -200 fleet:
Note 1: Where there are differences between the AD and the
Supplemental Structural Inspection Document, the AD prevails.
(a) For airplanes listed in Section 3.0 of Boeing Document No.
D6-37089, ``Supplemental Structural Inspection Document'' (SSID),
Revision B, dated February 18, 1987, and Revision C, dated January
1990: Within 12 months after August 9, 1991 (the effective date of
AD 91-14-20, amendment 39-7061), incorporate a revision into the
FAA-approved maintenance inspection program which provides no less
than the required damage tolerance rating (DTR) for each Structural
Significant Item (SSI) listed in that document. (The required DTR
value for each SSI is listed in the document.) The revision to the
maintenance program shall include and shall be implemented in
accordance with the procedures in Sections 5.0 and 6.0 of the SSID.
This revision shall be deleted following accomplishment of the
requirements of paragraph (b) of this AD.
Note 2: For the purposes of this AD, an SSI is defined as a
principal structural element that could fail and consequently reduce
the structural integrity of the airplane.
(b) Prior to reaching the threshold specified in paragraph (c)
of this AD, or within 12 months after the effective date of this AD,
whichever occurs later, incorporate a revision into the FAA-approved
maintenance or inspection program that provides no less than the
required DTR for each SSI listed in Boeing Document No. D6-37089,
``Supplemental Structural Inspection Document'' (SSID), Revision D,
dated June 1995 (hereinafter referred to as ``Revision D''). (The
required DTR value for each SSI is listed in the document.) Except
as provided to the contrary in paragraphs (c), (d), and (g) of this
AD, the revision to the maintenance or inspection program shall
include and shall be implemented in accordance with the procedures
in Section 5.0, ``Damage Tolerance Rating (DTR) System Application''
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and Section 6.0, ``SSI Discrepancy Reporting'' of Revision D. Upon
incorporation of the revision required by this paragraph, the
revision required by paragraph (a) of this AD may be deleted.
(c) Except as provided in paragraph (d), (e), or (g) of this AD,
perform an inspection to detect cracks in all structure identified
in Revision D at the time specified in paragraph (c)(1) or (c)(2) of
this AD, as applicable.
(1) For Model 737-200C series airplanes: Inspect prior to the
accumulation of 46,000 total flight cycles, or within 4,000 flight
cycles measured from the date 12 months after the effective date of
this AD, whichever occurs later.
Note 3: The requirements specified in paragraph (c)(1) of this
AD only apply to airplanes listed as 737-200C on the type
certificate data sheet. Paragraph (c)(1) does not apply to airplanes
that have been modified from a passenger configuration to an all-
cargo configuration by supplemental type certificate (STC).
Paragraphs (c)(2) and (d) apply to those airplanes.
(2) For all airplanes, except for those airplanes identified in
paragraph (c)(1) of this AD: Inspect prior to the accumulation of
66,000 total flight cycles, or within 4,000 flight cycles measured
from the date 12 months after the effective date of this AD,
whichever occurs later.
Note 4: Notwithstanding the provisions of paragraphs 5.1.1,
5.1.2, 5.1.6(e), 5.1.11, 5.1.12, 5.1.13, 5.2, 5.2.1, 5.2.2, 5.2.3,
and 5.2.4 of the General Instructions of Revision D, which would
permit operators to perform fleet and rotational sampling
inspections, to perform inspections on less than whole airplane
fleet sizes and to perform inspections on substitute airplanes, this
AD requires that all airplanes that exceed the threshold be
inspected in accordance with Revision D.
Note 5: Once the initial inspection has been performed,
operators are required to perform repetitive inspections at the
intervals specified in Revision D in order to remain in compliance
with their maintenance or inspection programs, as revised in
accordance with paragraph (b) of this AD.
(d) For airplanes on which the structure identified in Revision
D has been physically altered in accordance with an STC prior to the
effective date of this AD: Accomplish the requirements specified in
paragraph (d)(1) or (d)(2) of this AD.
(1) Within 18 months after the effective date of this AD, assess
the damage tolerance characteristics of each SSI created or affected
by each STC to determine the effectiveness of the applicable
Revision D inspection for each SSI and, if not effective, revise the
FAA-approved maintenance or inspection program to include an
inspection method for each new or affected SSI, and to include the
compliance times for initial and repetitive accomplishment of each
inspection. Following accomplishment of the revision and within the
compliance times established, perform an inspection to detect cracks
in the structure affected by any design change or repair, in
accordance with the new inspection method. The new inspection method
and the compliance times shall be approved by the Manager, Seattle
Aircraft Certification Office (ACO), FAA, Transport Airplane
Directorate.
Note 6: For purposes of this AD, an SSI is ``affected'' if it
has been physically altered or repaired, or if the loads acting on
the SSI have been increased or redistributed. The effectiveness of
the applicable inspection method and compliance time should be
determined based on a damage tolerance assessment methodology, such
as that described in FAA Advisory Circular AC No. 91-56, Change 2,
dated April 15, 1983.
(2) Accomplish paragraphs (d)(2)(i), (d)(2)(ii), and (d)(2)(iii)
of this AD.
(i) Within 18 months after the effective date of this AD, submit
a plan that describes a methodology for accomplishing the
requirements of paragraph (d)(1) of this AD to the Manager, Seattle
ACO, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; fax (425)
227-1181.
Note 7: The plan should include a detailed description of the:
STC; methodology for identifying new or affected SSI's; method for
developing loads and validating the analysis; methodology for
evaluating and analyzing the damage tolerance characteristics of
each new or affected SSI; and proposed inspection method. The plan
would not need to include all of these elements if the operator can
otherwise demonstrate that its plan will enable the operator to
comply with paragraph (d)(2)(iii) of this AD.
(ii) Within 18 months after the effective date of this AD,
perform a detailed visual inspection in accordance with a method
approved by the Manager, Seattle ACO to detect cracks in all
structure identified in Revision D that has been altered by an STC.
(A) If no crack is detected, repeat the detailed visual
inspection thereafter at intervals not to exceed 18 months.
(B) If any crack is detected, prior to further flight, repair it
in accordance with a method approved by the Manager, Seattle ACO.
(iii) Within 48 months after the effective date of this AD,
revise the FAA-approved maintenance or inspection program to include
an inspection method for each new or affected SSI, and to include
the compliance times for initial and repetitive accomplishment of
each inspection. The inspection methods and the compliance times
shall be approved by the Manager, Seattle ACO. Accomplishment of the
actions specified in this paragraph constitutes terminating action
for the repetitive inspection requirements of paragraph
(d)(2)(ii)(A) of this AD.
Note 8: Notwithstanding the provisions of paragraphs 5.1.17 and
5.1.18 of the General Instructions of Revision D, which would permit
deletions of modified, altered, or repaired structure from the SSIP,
the inspection of SSI's that are modified, altered, or repaired
shall be done in accordance with a method approved by the Manager,
Seattle ACO.
(e) For airplanes on which the structure identified in Revision
D has been repaired or physically altered by any design change other
than an STC identified in paragraph (d), prior to the effective date
of this AD: At the time of the first inspection of each SSI after
the effective date of this AD in accordance with Revision D,
identify each repair or design change to that SSI. Within 12 months
after such identification, assess the damage tolerance
characteristics of each SSI created or affected by each repair or
design change to determine the effectiveness of the applicable SSID
inspection for each SSI and, if not effective, revise the FAA-
approved maintenance or inspection program to include an inspection
method and compliance times for each new or affected SSI. The new
inspection method and the compliance times shall be approved by the
Manager, Seattle ACO.
Note 9: For the purposes of this AD, a design change is defined
as any modification, alteration, or change to operating limitations.
(f) Except as provided in paragraph (d)(2)(ii)(B) of this AD,
cracked structure found during any inspection required by this AD
shall be repaired, prior to further flight, in accordance with an
FAA-approved method.
(g) For airplanes on which the structure identified in Revision
D is affected by any design change (including STC's) or repair that
is accomplished after the effective date of this AD: Within 12
months after that modification, alteration, or repair, assess the
damage tolerance characteristics of each SSI created or affected by
each repair or design change to determine the effectiveness of the
applicable SSID inspection for each SSI and, if not effective,
revise the FAA-approved maintenance or inspection program to include
an inspection method and compliance times for each new or affected
SSI, and to include the compliance times for initial and repetitive
accomplishment of each inspection. The new inspection method and the
compliance times shall be approved by the Manager, Seattle ACO.
Note 10: Notwithstanding the provisions of paragraphs 5.1.17 and
5.1.18 of the General Instructions of Revision D, which would permit
deletions of modified, altered, or repaired structure from the SIP,
the inspection of SSI's that are modified, altered, or repaired
shall be done in accordance with a method approved by the Manager,
Seattle ACO.
(h) Before any airplane that is subject to this AD and that has
exceeded the applicable compliance times specified in paragraph (c)
of this AD can be added to an air carrier's operations
specifications, a program for the accomplishment of the inspections
required by this AD must be established in accordance with paragraph
(h)(1) or (h)(2) of this AD, as applicable.
(1) For airplanes that have been inspected in accordance with
this AD, the inspection of each SSI must be accomplished by the new
operator in accordance with the previous operator's schedule and
inspection method, or the new operator's schedule and inspection
method, whichever would result in the earlier accomplishment date
for that SSI inspection. The compliance time for accomplishment of
this inspection must be measured from the last inspection
accomplished by the previous operator. After each inspection has
been performed once, each subsequent inspection must be
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performed in accordance with the new operator's schedule and
inspection method.
(2) For airplanes that have not been inspected in accordance
with this AD, the inspection of each SSI required by this AD must be
accomplished either prior to adding the airplane to the air
carrier's operations specification, or in accordance with a schedule
and an inspection method approved by the Manager, Seattle ACO. After
each inspection has been performed once, each subsequent inspection
must be performed in accordance with the new operator's schedule.
(i)(1) 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 11: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(2) Alternative methods of compliance, approved previously in
accordance with AD 91-14-20, amendment 39-7061, are not considered
to be approved as alternative methods of compliance with this AD.
(j) 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.
(k) The actions specified in paragraphs (b) and (c) shall be
done in accordance with Boeing Document No. D6-37089, ``Supplemental
Structural Inspection Document'' (SSID), Revision D, dated June
1995, which contains the following list of effective pages:
------------------------------------------------------------------------
Page number shown on page Revision level shown on page
------------------------------------------------------------------------
List of Effective Pages................... D
Pages 1 thru 10
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(Note: The issue date of Revision D is indicated only on the
title page; no other page of the document is dated.). This
incorporation by reference was approved previously by the Director
of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1
CFR part 51, as of June 23, 1998 (63 FR 27465, May 19, 1998). 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 FAA, the FAA, Transport Airplane Directorate,
Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California; or at the Office of the Federal Register, 800
North Capitol Street, NW., suite 700, Washington, DC.
(l) The effective date of this amendment remains June 23, 1998.
Issued in Renton, Washington, on December 30, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-184 Filed 1-6-99; 8:45 am]
BILLING CODE 4910-13-U
