[Federal Register Volume 66, Number 78 (Monday, April 23, 2001)]
[Rules and Regulations]
[Pages 20383-20386]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-9663]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-NM-42-AD; Amendment 39-12179; AD 2001-08-02]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 707 and 720 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment supersedes two existing airworthiness
directives (AD), applicable to all Boeing Model 707 and 720 series
airplanes, that currently require inspections of the upper chords of
the wing front and rear spars, repair, if necessary, and application of
corrosion inhibitor to the inspected areas. This amendment requires
repetitive inspections of the upper and lower chords on the wing front
and rear spars, repair, if necessary, and application of corrosion
inhibitor to the inspected areas. These actions are necessary to find
and fix stress corrosion cracking of the upper and lower chords on the
wing front and rear spars, which could result in reduced structural
integrity of the wing. This action is intended to address the
identified unsafe condition.
DATES: Effective May 8, 2001.
The incorporation by reference of certain publications, as listed
in the regulations, is approved by the Director of the Federal Register
as of May 8, 2001.
The incorporation by reference of Boeing Service Bulletin 3240,
Revision 3, dated October 18, 1985, as listed in the regulations, was
approved previously by the Director of the Federal Register as of March
10, 1992 (57 FR 4153, February 4, 1992).
Comments for inclusion in the Rules Docket must be received on or
before June 22, 2001.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2001-NM-42-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. Comments may be submitted via fax to (425) 227-1232.
Comments may also be sent via the
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Internet using the following address: [email protected].
Comments sent via fax or the Internet must contain ``Docket No. 2001-
NM-42-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 for Windows or ASCII text.
The service information referenced in this AD 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; or at
the Office of the Federal Register, 800 North Capitol Street, NW.,
suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Duong Tran, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2773; fax (425) 227-1181.
SUPPLEMENTARY INFORMATION: On May 28, 1986, the FAA issued AD 86-11-06,
amendment 39-5327 (51 FR 20249, June 4, 1986), applicable to certain
Boeing Model 707 and 720 series airplanes, to require repetitive
inspections to detect cracks or corrosion of the upper chord of the
wing front spar, repair, if necessary, and application of corrosion
inhibitor. The actions required by that AD are intended to ensure
continued structural integrity of the upper chord of the wing front
spar.
On January 17, 1992, the FAA issued AD 92-03-12, amendment 39-8169
(57 FR 4153, February 4, 1992), applicable to certain Boeing Model 707
and 720 series airplanes, to require repetitive inspections to detect
cracks or corrosion of the upper chord of the wing rear spar, repair,
if necessary, and application of corrosion inhibitor. The actions
required by that AD are intended to ensure continued structural
integrity of the upper chord of the wing rear spar.
Actions Since Issuance of Previous Rule
Since the issuance of those AD's, a 31-inch crack was found in the
radius of the lower chord of the wing front spar in the dry bay area
between wing stations 360 and 400. Investigation revealed that 19
inches of the crack were due to stress corrosion, while the remainder
was due to ductile separation. While the existing AD's require
repetitive inspections to detect cracks or corrosion of the upper chord
of the wing front and rear spars, engineering evaluation suggests that
both upper and lower chords on the front and rear spars may be subject
to such cracking. Cracking of an upper or lower chord of the wing front
or rear spar, if not found, could result in reduced structural
integrity of the wing.
Explanation of Relevant Service Information
AD 86-11-06 requires inspections of the upper chord of the wing
front spar per Boeing Service Bulletin 3240, Revision 1, dated November
13, 1981, Revision 2, dated May 3, 1985, or Revision 3, dated October
18, 1985. AD 92-03-12 requires inspections of the upper chord of the
wing rear spar per Boeing Service Bulletin 3240, Revision 3. Since the
issuance of those AD's, Boeing has issued All Base Message (ABM) M-
7200-01-00062, dated January 5, 2001. The ABM modifies the procedures
described in Boeing Service Bulletin 3240, Revision 3, to emphasize
certain procedures for solvent cleaning, detailed visual inspections
(referred to in the service bulletin and the ABM as ``close visual
inspections'') to detect corrosion or cracking of the upper and lower
chords on the wing front and rear spars, application of surface finish,
and application of corrosion inhibitor. The ABM also recommends a new
compliance time for accomplishment of the next inspection. Performing
inspections and follow-on actions per Revision 3 of the service
bulletin as revised by the ABM eliminates the need for the inspections
required by the existing AD's.
Explanation of Requirements of Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of this same type design, this AD
supersedes AD 86-11-06 and AD 92-03-12 to continue to require the
inspections and follow-on actions required by those AD's. This AD also
requires accomplishment of the actions specified in the service
bulletin as modified by the procedures in the ABM described previously,
except as discussed below. Once the new requirements of this AD have
been done, the inspections per the old AD's are no longer required.
Differences Between Service Information and This AD
This AD differs from the service information in these ways:
If any crack or corrosion is found, this AD requires
repair of such damage before further flight. However, the service
bulletin specifies that stop drilling of cracks allows the repair to be
deferred. The FAA finds that stop drilling is not adequate to arrest
stress corrosion cracking; thus, stop drilling is not adequate to
ensure the safety of the affected airplane fleet. Thus, this AD
requires that any cracking or corrosion that is found be repaired
before further flight.
Also, although the service bulletin specifies that the
manufacturer may be contacted for disposition of certain repair
conditions, this AD requires the repair of those conditions to be done
per a method approved by the FAA, or per data meeting the type
certification basis of the airplane approved by a Boeing Company
Designated Engineering Representative who has been authorized by the
Manager, Seattle ACO, to make such findings.
Explanation of Changes in Restatement of Requirements of Existing
AD's
Paragraphs (a) through (i) restate the requirements of AD 86-11-06
and AD 92-03-12. Certain existing requirements specify ``close visual
inspections.'' The FAA finds that ``detailed visual inspection'' is a
more accurate term for the type of inspections that are required.
Therefore, the FAA has revised the existing requirements as stated in
paragraphs (a) and (f) of this AD to identify the required inspections
as ``detailed visual inspections.'' Also, Note 2 has been added to
include a definition of ``detailed visual inspection.''
Additionally, the restatement of requirements of the existing AD's
has been revised to remove all references to the use of ``later FAA-
approved revisions'' of Boeing Service Bulletin 3240, Revision 1, in
order to be consistent with FAA policy in that regard. Instead, the FAA
has listed the specific revisions of the service bulletin that have
been approved. The FAA has determined that this change will not
increase the economic burden on any operator, nor will it increase the
scope of the AD.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
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.
Communications shall identify the
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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.
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 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 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 2001-NM-42-AD.'' The postcard will be date-stamped and
returned to the commenter.
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.
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, 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 amendments 39-5327 (51 FR
20249, June 4, 1986) and 39-8169 (57 FR 4153, February 4, 1992), and by
adding a new airworthiness directive (AD), amendment 39-12179, to read
as follows:
2001-08-02 Boeing: Amendment 39-12179. Docket 2001-NM-42-AD.
Supersedes AD 86-11-06, Amendment 39-5327, and AD 92-03-12,
Amendment 39-8169.
Applicability: All Model 707 and 720 series airplanes,
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 (m) 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.
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.''
Compliance: Required as indicated, unless accomplished
previously.
To find and fix stress corrosion cracking of the upper and lower
spar chords on the front and rear spars of the wing, which could
result in reduced structural integrity of the wing, accomplish the
following:
Restatement of Requirements of AD 86-11-06
AD 86-11-06: Repetitive Inspections
(a) For Model 707 and 720 series airplanes with 15,000 or more
landings: Within 100 landings or 60 days after July 14, 1986 (the
effective date of AD 86-11-06, amendment 39-5327), unless previously
accomplished within the last 900 landings or 305 days prior to July
14, 1986, perform a detailed visual inspection of the wing front
spar upper chord for cracks and corrosion, in accordance with Boeing
Service Bulletin 3240, Revision 1, dated November 13, 1981, Revision
2, dated May 3, 1985, or Revision 3, dated October 18, 1985. Repeat
the inspection thereafter at intervals not to exceed 1,000 landings
or one year, whichever occurs first.
AD 86-11-06: Repair
(b) If cracks or corrosion are found during the inspection per
paragraph (a) of this AD, repair prior to further flight in
accordance with Boeing Service Bulletin 3240, Revision 3, dated
October 18, 1985.
AD 86-11-06: Stop Drilling, Repetitive Inspections, and Permanent
Repair
(c) For airplanes subject to paragraph (a) of this AD: Cracks
which have been repaired in accordance with the ``stop drilling''
procedure described in Part III, Figure 2, of Boeing Service
Bulletin 3240, Revision 1, dated November 13, 1981, Revision 2,
dated May 3, 1985, or Revision 3, dated October 18, 1985, must be
visually inspected at intervals not to exceed 300 landings, until
permanently repaired in accordance with Part III, Figure 2, of
Service Bulletin 3240, Revision 3, dated October 18, 1985. A
permanent repair must be completed within 1,000 landings or one
year, whichever occurs first after July 14, 1986.
AD 86-11-06: Repair Per Earlier Service Bulletins
(d) For airplanes subject to paragraph (a) of this AD: Cracks
greater than 2.0 inches in length, which have been previously
repaired in accordance with Boeing Service Bulletin 3240, Revision
1, dated November 13, 1981, or Revision 2, dated May 3, 1985, must
be repaired in accordance with Revision 3, dated October 18, 1985,
within 1,000 landings or one year, whichever occurs first after July
14, 1986.
AD 86-11-06: Application of Corrosion Inhibitor
(e) For airplanes subject to paragraph (a) of this AD: After
each of the above inspections and repairs have been performed, apply
BMS-3-23 corrosion inhibitor, or equivalent, to the affected areas.
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Restatement of Requirements of AD 92-03-12
AD 92-03-12: Repetitive Inspections
(f) For all Model 707 and 720 series airplanes: Perform a
detailed visual inspection for cracks and corrosion of the wing rear
spar upper chord from wing station (WS) 109.45 to WS 360 for Model
707-300 series airplanes; or from WS 180.71 to WS 360 for Model 720,
707-100, and 707-200 series airplanes; at rib and stiffener
locations. Inspect in accordance with Boeing Service Bulletin 3240,
Revision 3, dated October 18, 1985, prior to the later of the times
specified in subparagraphs (f)(1) and (f)(2) of this AD, unless
previously accomplished within the last 900 flight cycles or 335
days prior to June 19, 1991 (the effective date of AD 91-11-06).
Repeat the inspection at intervals not to exceed 1,000 flight cycles
or one year, whichever occurs first.
(1) Within the next 30 days or 100 flight cycles after June 19,
1991; or
(2) Prior to the accumulation of 10,000 total flight cycles.
AD 92-03-12: Corrective Actions
(g) If cracks or corrosion areas are found during any inspection
per paragraph (f) of this AD, prior to further flight, accomplish
either subparagraph (g)(1) or (g)(2) of this AD:
(1) Repair, other than by stop drill procedure, in accordance
with Part III, Figure 2, of Boeing Service Bulletin 3240, Revision
3, dated October 18, 1985 (this is considered the ``final repair''),
or
(2) Repair in accordance with the stop drill procedures
specified in Part III, Figure 2, of Boeing Service Bulletin 3240,
Revision 3, dated October 18, 1985. This repair method may only be
used provided that the limitations specified in Part III, Figure 2,
Items 5a and 5b, of the service bulletin are met.
(i) Immediately after stop drilling, conduct an eddy current
inspection of the stop drill hole in accordance with the
instructions in Section 5-5-1 of Boeing Document D6-7170,
Nondestructive Test Document, to ensure that the crack does not
extend beyond the stop drill. Thereafter, inspect visually for crack
growth beyond the stop drill at intervals not exceeding 300 flight
cycles.
(ii) If crack growth beyond the stop drill occurs, prior to
further flight, accomplish the final repair in accordance with
paragraph (g)(1) of this AD.
(iii) Within 1,000 flight cycles or one year, whichever occurs
first, after the stop drill has been accomplished, accomplish the
final repair in accordance with paragraph (g)(1) of this AD.
AD 92-03-12: Inspection of Previously Stop Drilled Cracks
(h) If previously stop drilled cracks are found during any
inspection required by paragraph (f) of this AD, conduct an eddy
current inspection of the stop drill hole for crack growth beyond
the stop drill, in accordance with the instructions in Section 5-5-1
of Boeing Document D6-7170, Nondestructive Test Document.
(1) If growth beyond the stop drill has occurred, prior to
further flight, repair in accordance with paragraph (g)(1) of this
AD.
(2) If growth beyond the stop drill has not occurred, and the
limitations specified in Part III, Figure 2, Items 5a and 5b, of
Boeing Service Bulletin 3240, Revision 3, dated October 18, 1985,
are met, prior to further flight accomplish either subparagraph
(h)(1)(i) or (h)(1)(ii) of this AD:
(i) Repair in accordance with paragraph (g)(1) of this AD; or
(ii) Reinspect visually for crack growth beyond the stop drill
at intervals not exceeding 300 flight cycles.
(A) If crack growth beyond the stop drill occurs, prior to
further flight, accomplish the final repair in accordance with
paragraph (g)(1) of this AD.
(B) Within 1,000 flight cycles or one year, whichever occurs
first after the initial inspection revealed the stop drill crack,
accomplish the final repair in accordance with paragraph (g)(1) of
this AD.
AD 92-03-12: Application of Corrosion Inhibitor
(i) After each of the inspections and repairs required by
paragraphs (f) and (g) of this AD have been performed, apply BMS 3-
23 corrosion inhibitor, or equivalent, to the affected areas.
New Requirements of this AD
New Repetitive Detailed Visual Inspections
(j) Within 30 days after the effective date of this AD, do a
detailed visual inspection for corrosion or cracking of the upper
and lower chords on the front and rear spars, per Boeing Service
Bulletin 3240, Revision 3, dated October 18, 1985, as modified by
Boeing All Base Message (ABM) M-7200-01-00062, dated January 5,
2001. Repeat the inspections thereafter at least every 6 months or
1,000 flight cycles, whichever comes first. Doing the initial
inspection per this paragraph terminates the inspections required by
paragraphs (a) and (f) of this AD.
Note 3: There is no terminating action available for the
repetitive inspections required by paragraph (j) of this AD.
Repair
(k) If any cracking or corrosion is found during any inspection
per paragraph (j) of this AD: Before further flight, repair per
Boeing Service Bulletin 3240, Revision 3, dated October 18, 1985, as
modified by Boeing ABM M-7200-01-00062, dated January 5, 2001,
except, where the service information specifies to contact Boeing
for repair instructions, before further flight, repair per a method
approved by the Manager, Seattle Aircraft Certification Office
(ACO), FAA; or per data meeting the type certification basis of the
airplane approved by a Boeing Company Designated Engineering
Representative who has been authorized by the Manager, Seattle ACO,
to make such findings. For a repair method to be approved by the
Manager, Seattle ACO, as required by this paragraph, the approval
letter must specifically reference this AD.
Note 4: ``Stop drilling'' of cracks as a means to defer repair,
as specified in Boeing Service Bulletin 3240, Revision 3, dated
October 18, 1985, is Not allowed by paragraph (k) of this AD.
Application of Corrosion Inhibitor
(l) After each inspection required by paragraph (j) of this AD
and any repair per paragraph (k) of this AD, before further flight,
apply BMS 3-23 corrosion inhibitor to the affected areas.
Alternative Methods of Compliance
(m) 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 5: 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
(n) Special flight permits may be issued in accordance with
Secs. 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
(o) Except as provided by paragraph (e), (g)(2)(ii), (h), (i),
(k), and (l) of this AD; the actions shall be done in accordance
with Boeing Service Bulletin 3240, Revision 1, dated November 13,
1981; Boeing Service Bulletin 3240, Revision 2, dated May 3, 1985;
Boeing Service Bulletin 3240, Revision 3, dated October 18, 1985; or
Boeing All Base Message M-7200-01-00062, dated January 5, 2001; as
applicable.
(1) The incorporation by reference of Boeing Service Bulletin
3240, Revision 1, dated November 13, 1981; Boeing Service Bulletin
3240, Revision 2, dated May 3, 1985; and Boeing All Base Message M-
7200-01-00062, dated January 5, 2001, is approved by the Director of
the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR
part 51.
(2) The incorporation by reference of Boeing Service Bulletin
3240, Revision 3, dated October 18, 1985, was approved previously by
the Director of the Federal Register as of March 10, 1992 (57 FR
4153, February 4, 1992).
(3) 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
(p) This amendment becomes effective on May 8, 2001.
Issued in Renton, Washington, on April 11, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 01-9663 Filed 4-20-01; 8:45 am]
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