[Federal Register: April 16, 2003 (Volume 68, Number 73)]
[Proposed Rules]
[Page 18567-18569]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16ap03-17]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-NM-184-AD]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-8-11, DC-8-
12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, and DC-8-43
Airplanes; Model DC-8-50 Series Airplanes; Model DC-8F-54 and DC-8F-55
Airplanes; Model DC-8-60 Series Airplanes; Model DC-8-70 Series
Airplanes; and Model DC-8-70F Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain McDonnell Douglas
airplanes. This proposal would require an inspection to determine the
material composition of the auxiliary spar cap of the lower inboard of
the left and right wings. For certain airplanes, this proposal also
would require repetitive detailed and dye penetrant inspections for
cracking of the spar cap, and corrective actions if necessary. This
action is necessary to detect and correct stress corrosion cracking of
the auxiliary spar cap, which could cause excessive loads to the
structure attaching the support fitting of the main landing gear (MLG)
to the wing, and result in loss of the MLG. This action is intended to
address the identified unsafe condition.
DATES: Comments must be received by June 2, 2003.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2001-NM-184-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9 a.m. and 3 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 Internet using the following address:
9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must
contain ``Docket No. 2001-NM-184-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 the proposed rule may be
obtained from Boeing Commercial Aircraft Group, Long Beach Division,
3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data
and Service Management, Dept. C1-L5A (D800-0024). This information may
be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington FAA, or at the Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Jon Mowery, Aerospace Engineer,
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137;
telephone (562) 627-5322; fax (562) 627-5210.
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 action may be changed in
light of the comments received.
Submit comments using the following format:
[sbull] 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.
[sbull] For each issue, state what specific change to the proposed
AD is being requested.
[sbull] Include justification (e.g., reasons or data) for each
request.
[[Page 18568]]
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 action must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 2001-NM-184-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-114, Attention: Rules
Docket No. 2001-NM-184-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received numerous reports indicating that cracking has
occurred in the auxiliary spar cap of the lower inboard near the
outboard attach bolts on various McDonnell Douglas Model DC-8
airplanes. The cracking occurred on airplanes that have accumulated
more than 36,000 total flight hours. Investigation indicates that the
cracking appeared to be due to stress corrosion. Such cracking of the
auxiliary spar cap, if not detected and corrected, could cause
excessive loads on the structure attaching the support fitting of the
main landing gear (MLG) to the wing, and result in loss of the MLG.
Explanation of Relevant Service Information
The FAA has reviewed and approved McDonnell Douglas DC-8 Service
Bulletin 57-85, Revision 1, dated July 5, 1991. That service bulletin
describes procedures for performing repetitive detailed and dye
penetrant inspections to detect stress cracking of the auxiliary spar
cap of the lower inboard of the left and right wings. For cracking that
is within certain limits, the service bulletin describes corrective
actions such as repair or rework and application of corrosion-
inhibiting compound, if necessary. For any cracking that is outside the
limits specified in the service bulletin, the service bulletin
describes procedures for replacing the auxiliary spar cap with either a
new spar cap made with 7075-T6 aluminum or with a new, improved spar
cap made with 7075-T73 aluminum. Additionally, for any cracking that is
detected at the bathtub end of both forward and aft bolt holes, the
service bulletin describes procedures for replacement of those MLG
fittings with new or serviceable fittings. Accomplishment of the
actions specified in the service bulletin is intended to adequately
address the identified unsafe condition.
Explanation of Requirements of Proposed Rule
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 require an inspection to determine the material
composition of the auxiliary spar cap. If the spar cap is made of 7075-
T6 aluminum, the proposed AD would require accomplishment of the
actions and procedures specified in the service bulletin described
above for the repetitive inspections for cracking, and repair, rework,
and replacement of the spar cap if necessary.
Operators should note that the FAA has received information
indicating that there may be a parts availability problem in procuring
spar caps made of 7075-T73 aluminum. However, we have determined that
the repetitive inspections proposed by this AD can be allowed to
continue in lieu of accomplishment of the terminating action
(replacement of both spar caps with caps made of 7075-T73 aluminum). In
making this determination, we consider that, in this case, long-term
continued operational safety will be adequately assured by
accomplishing the repetitive inspections to detect cracking of the
auxiliary spar cap before it represents a hazard to the airplane.
Differences Between This NPRM and the Service Information
The FAA considers that, prior to performing the inspections and
corrective actions described in the service bulletin above, it is
necessary to perform an inspection to determine the material
composition of the auxiliary spar cap of the lower inboard of the left
and right wings. That inspection may be done per a method approved by
the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, or
by performing an eddy current test of the auxiliary spar cap per the
Non-Destructive Testing Standard Practice Manual MDC-93K0393 (NDTSPM)
06-10-01.006. If the auxiliary spar cap is composed of 7075-T6
aluminum, this proposed AD would require accomplishment of the actions
specified in the service bulletin described above, as applicable.
Additionally, operators should note that, although the service
bulletin specifies that the manufacturer may be contacted for
disposition of certain cracking outside the limits specified in the
service bulletin, this proposal would require the disposition of any
such cracking that was detected to be accomplished per a method
approved by the FAA.
Cost Impact
There are approximately 264 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 244 airplanes of U.S. registry
would be affected by this proposed AD. We estimate that it would take
approximately 2 work hours per airplane to accomplish the proposed
inspection to determine the material of the spar cap. We estimate that
the average labor rate is $60 per work hour. Based on these figures,
the cost impact of the proposed AD on U.S. operators is estimated to be
$29,280, or $120 per airplane, per inspection cycle.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the proposed requirements of
this AD action, and that no operator would accomplish those actions in
the future if this proposed 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 proposed herein would 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 proposal would not have federalism implications
under Executive Order 13132.
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
[[Page 18569]]
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. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
McDonnell Douglas: Docket 2001-NM-184-AD.
Applicability: Model DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-
32, DC-8-33, DC-8-41, DC-8-42, and DC-8-43 airplanes; Model DC-8-51,
DC-8-52, DC-8-53, and DC-8-55 airplanes; Model DC-8F-54 and DC-8F-55
airplanes; Model DC-8-61, DC-8-62, and DC-8-63 airplanes; Model DC-
8-61F, DC-8-62F, and DC-8-63F airplanes; Model DC-8-71, DC-8-72, and
DC-8-73 airplanes; as listed in McDonnell Douglas DC-8 Service
Bulletin 57-85, Revision 1, dated July 5, 1991; 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 (c) 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 detect and correct cracking of the auxiliary spar cap, which
could cause excessive loads to the structure attaching the support
fitting of the main landing gear (MLG) to the wing, and result in
loss of the MLG; accomplish the following:
Inspection To Determine the Material of the Auxiliary Spar Cap
(a) Within 24 months or 2,000 flight cycles after the effective
date of this AD, whichever occurs later, inspect to determine the
material composition of the auxiliary spar cap (Part Numbers
5615058-1 through -506 inclusive) of the lower inboard of the left
and right wings, in accordance with a method approved by the
Manager, Los Angeles Aircraft Certification Office (ACO), FAA, or by
performing an eddy current test of the auxiliary spar cap per the
Non-Destructive Testing Standard Practice Manual MDC-93K0393
(NDTSPM) 06-10-01.006. If the material of the spar cap is 7075-T73
aluminum, no further action is required by this paragraph.
Inspections for Cracking and Follow-on Corrective Actions
(b) If the material of the auxiliary spar cap found during the
inspection required by paragraph (a) of this AD is 7075-T6 aluminum:
Within 2 years or 2,000 flight cycles after accomplishing the
inspection required by paragraph (a) of this AD, perform a detailed
inspection and a dye penetrant inspection for cracking of the
auxiliary spar cap and the bathtub end of either the forward or the
aft bolt hole of the lower inboard of the left and right wings, as
applicable, per McDonnell Douglas DC-8 Service Bulletin 57-85,
Revision 1, dated July 5, 1991.
Note 2: For the purposes of this AD, a detailed 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.''
(1) If no cracking is detected, repeat the inspection at
intervals not to exceed 6,400 flight hours, until the auxiliary spar
cap is replaced with a spar cap made with 7075-T73 aluminum, in
accordance with the service bulletin.
(2) If any cracking of the auxiliary spar cap or at the bathtub
end of either the forward or the aft bolt hole is detected that is
within the limits specified in the service bulletin, before further
flight, rework or repair the spar cap, as applicable, and apply
corrosion inhibiting compound, in accordance with the service
bulletin. Repeat the inspection for cracking at intervals not to
exceed 1,600 flight hours, until the auxiliary spar cap is replaced
with a spar cap composed of 7075-T73 aluminum. Replacement of both
spar caps with 7075-T73 aluminum is terminating action for the
requirements of this AD.
(3) If any cracking at the bathtub end of both the forward and
aft bolt holes is detected that is within the limits specified in
the service bulletin, before further flight, replace the MLG fitting
with a new or serviceable fitting, in accordance with the service
bulletin.
(4) If any cracking of the auxiliary spar cap is detected that
is outside the limits specified in the service bulletin, before
further flight, replace the auxiliary spar cap with a cap composed
of 7075-T73 aluminum, in accordance with the service bulletin, or by
a method approved by the Manager, Los Angeles Aircraft Certification
Office (ACO), FAA. For a repair method to be approved by the
Manager, Los Angeles ACO, as required by this paragraph, the
Manager's approval letter must specifically reference this AD.
Alternative Methods of Compliance
(c) 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, Los Angeles ACO, FAA. Operators
shall submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Los Angeles ACO, FAA.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
Special Flight Permits
(d) Special flight permits may be issued in accordance with
Sec. Sec. 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 April 8, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-9302 Filed 4-15-03; 8:45 am]
BILLING CODE 4910-13-P