[Federal Register Volume 64, Number 73 (Friday, April 16, 1999)]
[Rules and Regulations]
[Pages 18802-18804]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-9253]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-197-AD; Amendment 39-11131; AD 99-08-22]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-10 Series
Airplanes and KC-10 (Military) Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to certain McDonnell Douglas Model DC-10 series airplanes
and KC-10 (military) airplanes, that requires repetitive inspections to
detect fatigue cracking of the rear spar cap of the horizontal
stabilizer; and repair, if necessary. The amendment also would require
a preventive modification of the rear spar cap of the horizontal
stabilizer, which would constitute terminating action for the
repetitive inspections. This amendment is prompted by reports of
fatigue cracking of the rear spar cap of the horizontal stabilizer. The
actions specified by this amendment are intended to prevent fatigue
cracking of the rear spar cap of the horizontal stabilizer, which could
result in reduced structural integrity of the horizontal stabilizer,
and consequent reduced controllability of the airplane.
DATES: Effective May 21, 1999.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of May 21, 1999.
ADDRESSES: The service information referenced in this AD may be
obtained from The Boeing Company, Douglas Products Division, 3855
Lakewood Boulevard, Long Beach, California 90846, Attention: Technical
Publications Business Administration, Dept. C1-L51 (2-60). 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 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.
FOR FURTHER INFORMATION CONTACT: Ron Atmur, Aerospace Engineer,
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los
Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California 90712-4137; telephone (562) 627-5224; fax (562)
627-5210.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to certain McDonnell Douglas Model
DC-10 series airplanes and KC-10 (military) airplanes was published in
the Federal Register on August 4, 1998 (63 FR 41479). That action
proposed to require repetitive penetrant inspections or high frequency
eddy current inspections to detect fatigue cracking of the rear spar
cap of the horizontal stabilizer; and repair, if necessary. That action
also proposed to require a preventive modification of the rear spar cap
of the horizontal stabilizer, which would constitute terminating action
for the repetitive inspections.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Support for the Proposal
One commenter supports the proposed rule.
Request To Revise the Compliance Time of the Terminating Action
One commenter requests that the proposed compliance time for
accomplishment of the terminating modification be revised from ``within
5 years'' to ``within 5 years or prior to the accumulation of 18,000
landings after the effective date of the AD, whichever occurs later.''
The commenter contends that such a revision of the compliance time
would allow the preventive modification installation on low-time DC-10
series airplanes to be consistent with the initial inspection threshold
of the proposal.
The FAA concurs partially. It is appropriate to specify an 18,000-
landing compliance time for accomplishment of the terminating action.
However, to be consistent with the compliance time specified in
paragraph (a) of this AD, that threshold must include total landings
accumulated on the airplane, not just those accumulated after the
effective of this AD, as requested by the commenter.
Requests for Credit for Previous Accomplishment of the AD
Requirements
One commenter requests that credit be given for previous
accomplishment of the proposed initial inspection. That commenter
specifically requests that credit for the initial inspection be given
if it was accomplished in accordance with McDonnell Douglas Comtwx DC-
10-COM-0047/SFY, dated December 11, 1997. Another commenter requests
that credit be given for initial inspections and installation of the
preventive modification that were accomplished prior to the effective
date of the AD in accordance with the service bulletin specified in the
proposal.
The FAA has reviewed the referenced comtwx and concurs that credit
may be given for the accomplishment of the initial inspection required
by this AD if it was done in accordance with the comtwx referenced by
the commenter. The FAA also notes that the comtwx is referenced in
McDonnell Douglas Alert Service Bulletin DC10-55A028, dated April 27,
1998, (which is the appropriate service information for this AD), as an
additional source of service information. Therefore, the FAA has
revised the final rule to add a new ``Note 2'' to give credit to
operators that may have accomplished previously the initial inspection
in accordance with McDonnell Douglas Comtwx DC-10-COM-0047/SFY, dated
December 11, 1997.
The FAA also concurs with the request to allow credit for
accomplishment of actions specified in McDonnell Douglas Alert Service
Bulletin DC10-55A028, dated April 27, 1998, that were accomplished
prior to the effective date of this AD. The FAA notes that operators
are generally given credit for work accomplished previously if the work
is performed in accordance with the final rule by means of the phrase
in the compliance section of the
[[Page 18803]]
AD that states, ``Required as indicated, unless accomplished
previously.'' Therefore, no change in the final rule is necessary in
this regard.
Request To Justify That Unsafe Condition Exists on Certain
Airplanes
One commenter notes that the horizontal stabilizer center section
of Model DC-10-30/40 series airplanes is different than that of Model
DC-10-10 series airplanes, and that reports of cracking of the rear
spar cap of the horizontal stabilizer have only occurred on Model DC-
10-10 series airplanes. Therefore, the commenter questions the need to
require installation of the proposed modification on DC-10-30/40 series
airplanes, and requests that the FAA provide justification that an
unsafe condition actually exists on the Model DC-10-30/40 series
airplanes. The FAA infers that the commenter is requesting the FAA
remove Model DC-10-30/40 series airplanes from the applicability of the
proposal if the FAA cannot justify that an unsafe condition exists for
that model.
The FAA does not concur that further justification of an unsafe
condition on DC-10-30/40 series airplanes is necessary, or that Model
DC-10-30/40 series models should be removed from the applicability of
this AD. Although the structure of the horizontal stabilizer center
section is thicker on Model DC-10-30/40 series airplanes than the same
structure on Model DC-10-10 series airplanes, the FAA finds that the
thicker structure is necessary because of the higher loads sustained by
Model DC-10-30/40 series airplanes. The airplane manufacturer also
concurs that fatigue cracking of the horizontal stabilizer is as likely
to develop on a Model DC-10-30/40 series airplane as on a Model DC-10-
10 series airplane. Therefore, no change to the final rule is
necessary.
Conclusion
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule with the changes previously
described. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Cost Impact
There are approximately 420 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 242 airplanes of U.S. registry
(124 Group 1 airplanes; 118 Group 2 airplanes) will be affected by this
AD.
It will take approximately 2 work hours per airplane to accomplish
the required inspections, at an average labor rate of $60 per work
hour. Based on these figures, the cost impact of the inspections
required by this AD on U.S. operators for Groups 1 and 2 airplanes is
estimated to be $29,040, or $120 per airplane, per inspection cycle.
It will take approximately 34 work hours per airplane to accomplish
the terminating modification, at an average labor rate of $60 per work
hour. Required parts will cost approximately $6,236 per airplane for
Group 1 airplanes, or $6,349 per airplane for Group 2 airplanes. Based
on these figures, the cost impact of the modification required by this
AD on U.S. operators of Group 1 airplanes is estimated to be
$1,026,224, or $8,276 per airplane; and, for Group 2 airplanes,
$989,902, or $8,389 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.
Regulatory Impact
The regulations adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
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 adding the following new
airworthiness directive:
99-08-22 McDonnell Douglas: Amendment 39-11131. Docket 98-NM-197-
AD.
Applicability: Model DC-10 series airplanes and KC-10 (military)
airplanes, as listed in McDonnell Douglas Alert Service Bulletin
DC10-55A028, dated April 27, 1998; 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 prevent fatigue cracking of the rear spar cap of the
horizontal stabilizer, which could result in reduced structural
integrity of the horizontal stabilizer, and consequent reduced
controllability of the airplane, accomplish the following:
(a) Prior to the accumulation of 18,000 total landings, or
within 1,500 landings after the effective date of this AD, whichever
occurs later: Perform a penetrant inspection or a high frequency
eddy current inspection to detect fatigue cracking of the rear spar
cap of the horizontal stabilizer, in accordance with McDonnell
Douglas Alert Service Bulletin DC10-55A028, dated April 27, 1998.
Note 2: Accomplishment of a penetrant inspection or a high
frequency eddy current inspection to detect fatigue cracking of the
rear spar cap of the horizontal stabilizer, in accordance with
McDonnell Douglas Comtwx DC-10-COM-0047/SFY, dated December 11,
1997, prior to the effective date of this AD, is acceptable for
compliance with the initial inspection requirements required by
paragraph (a) of this AD.
(1) If no cracking is detected, repeat the inspection thereafter
at intervals not to exceed 2,200 landings until accomplishment
[[Page 18804]]
of the requirements of paragraph (b) of this AD.
(2) If any cracking is detected, prior to further flight, repair
in accordance with the alert service bulletin. Repeat the inspection
thereafter at intervals not to exceed 2,200 landings until
accomplishment of the requirements of paragraph (b) of this AD.
(b) Within 5 years after the effective date of this AD or prior
to the accumulation of 18,000 total landings, whichever occurs
later: Perform a penetrant inspection or a high frequency eddy
current inspection to detect fatigue cracking of the rear spar cap
of the horizontal stabilizer, in accordance with McDonnell Douglas
Alert Service Bulletin DC10-55A028, dated April 27, 1998.
(1) If no cracking is detected, prior to further flight, perform
the preventive modification of the rear spar cap of the horizontal
stabilizer, in accordance with the alert service bulletin.
Accomplishment of this modification constitutes terminating action
for the requirements of this AD.
(2) If any cracking is detected, prior to further flight,
repair, and perform the preventive modification of the rear spar cap
of the horizontal stabilizer, in accordance with the alert service
bulletin. Accomplishment of the modification constitutes terminating
action for the requirements of 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 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, Los Angeles ACO.
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
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
(e) The actions shall be done in accordance with McDonnell
Douglas Alert Service Bulletin DC10-55A028, dated April 27, 1998.
This incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from The Boeing Company, Douglas Products
Division, 3855 Lakewood Boulevard, Long Beach, California 90846,
Attention: Technical Publications Business Administration, Dept. C1-
L51 (2-60) Copies may be inspected at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 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.
(f) This amendment becomes effective on May 21, 1999.
Issued in Renton, Washington, on April 7, 1999.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-9253 Filed 4-15-99; 8:45 am]
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