[Federal Register Volume 63, Number 243 (Friday, December 18, 1998)]
[Rules and Regulations]
[Pages 70005-70009]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-33389]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-06-AD; Amendment 39-10949; AD 98-26-09]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-9-10, -20, -
30, -40, and -50 Series Airplanes, and C-9 (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 DC9-10, -20, -30, -40,
and -50 series airplanes, and C-9 (military) airplanes, that requires a
one-time visual inspection to determine if the doorstops and corners of
the doorjamb of the forward passenger door have been modified, various
follow-on repetitive inspections, and modification, if necessary. This
amendment is prompted by reports of fatigue cracks found in the
fuselage skin and doubler at the corners and doorstops of the doorjamb
of the forward passenger door. The actions specified by this AD are
intended to detect and correct such fatigue cracking, which could
result in rapid decompression of the fuselage and consequent reduced
structural integrity of the airplane.
DATES: Effective January 22, 1999.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of January 22, 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: Wahib Mina, Aerospace Engineer,
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los
Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California 90712-4137; telephone (562) 627-5324; 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)
[[Page 70006]]
that is applicable to certain McDonnell Douglas Model DC-9-10, -20, -
30, -40, and -50 series airplanes, and C-9 (military) airplanes was
published in the Federal Register on April 20, 1998 (63 FR 19423). That
action proposed to require a one-time visual inspection to determine if
the doorstops and corners of the doorjamb of the forward passenger door
have been modified, various follow-on repetitive inspections, and
modification, if necessary.
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 Withdraw Proposed Rule
One commenter states that, while it has found cracking in the area
of the forward passenger door doorjamb over the past 15 years, findings
have tapered off. The commenter has found cracking through its FAA-
approved maintenance program, and continues to monitor the area through
that program. The commenter has not found a crack in the area adjacent
to a modified doorjamb. The area is not hidden and is presently
inspected at each ``C'' check. The commenter believes the forward
passenger door doorjamb is being maintained at a safe level without the
need of ``an AD note.''
The FAA infers from these remarks that the commenter requests the
proposed rule be withdrawn. The FAA does not concur. Based on fatigue
and damage tolerance analyses of cracked forward passenger door
doorjambs conducted by the manufacturer, the FAA finds that issuance of
this final rule is necessary to ensure an adequate level of safety for
the affected fleet.
Request To Extend Compliance Time
The same commenter requests that the FAA extend the proposed
compliance time for inspections of previously modified doorjams from
3,000 to 3,500 landings. The commenter indicates that this increase
would help bridge the inspection requirements into its maintenance
program. The commenter states that an added 500 landings will not cause
the condition of the doorjamb to develop into an unsafe condition with
the doorjamb modified previously. The commenter adds that since the
proposed grace period for the initial (one-time visual) inspection is
3,575 landings, the compliance time for inspections of modified
doorjambs should not be any different.
The FAA concurs with the commenter's request. Following careful
consideration of this comment, and in light of the commenter's
statement that no cracking has been found in the area adjacent to a
modified doorjamb during ``C'' check inspections, the FAA considers
that an extension of the repetitive inspection interval to 3,500
landings will not compromise safety. Paragraphs (c)(1) and (d) of this
final rule have been revised accordingly.
Request To Revise Inspection Intervals
Another commenter requests that the proposed initial inspection
intervals be changed to correspond with those presently in the DC-9
Supplemental Inspection Document (SID) program u--3 that is, initial
inspections should be required within a 3-year interval after the
effective date of the AD or prior to the accumulation of 48,000 total
landings, whichever occurs later, and repetitive intervals should
remain at 3,575 landings.
The FAA does not concur. The FAA has determined that cracking of
the forward passenger door doorjamb is fatigue related. The initial and
repetitive inspection intervals were calculated based on fatigue and
damage tolerance analyses. The FAA considers that revising the
compliance time as suggested by the commenter will not address the
identified unsafe condition in a timely manner.
Request To Revise DC-9 SID Program
One commenter requests that, prior to issuance of the final rule,
the DC-9 SID program be revised to eliminate the inspection
requirements of the SID in the area addressed by this proposed AD. The
commenter states that such revision will eliminate confusion between
the SID program and this proposed AD.
The FAA does not concur that the SID program should be revised
prior to issuance of this final rule. The actions required by this AD
area necessary to detect and correct the identified unsafe condition.
Following issuance of the final rule, the manufacturer may revise the
DC-9 SID program. However, to eliminate any confusion between this AD
and the SID program, the FAA has added a new paragraph (f) to this
final rule to specify that accomplishment of the actions required by
this AD constitutes terminating action for the requirements of AD 96-
13-03, amendment 39-9671 (61 FR 31009, June 19, 1996), for the affected
PSE. Since this new paragraph is being added, the FAA has removed
``NOTE 4'' of the proposed AD since it is no longer necessary.
Request To Revise Paragraph (e) of the Proposed Rule
One commenter requests that paragraph (e) of the proposed rule be
revised to require that, if the visual inspection required by paragraph
(a) of the AD reveals that the doorstops and corners of the forward
passenger door doorjamb have been modified previously in accordance
with FAA-approved repairs other than those specified in the DC-9
Structural Repair Manual (SRM) or Service Rework Drawing, prior to
further flight, an initial low frequency eddy current (LFEC) inspection
of the fuselage skin adjacent to the repair should be accomplished. If
no cracks are detected, repair should be required within 6 months; if
any crack is detected, repair should be required prior to further
flight. [As proposed, paragraph (e) requires that operators repair,
prior to further flight, in accordance with a method approved by the
FAA if the visual inspection required by paragraph (a) of the AD
reveals that the doorstops and corners of the forward passenger door
doorjamb have been modified previously, but not in accordance with the
McDonnell Douglas DC-9 SRM or the Service Rework Drawing.]
The commenter states that, as proposed, the requirement will cause
an unnecessary operational impact since FAA-approved, non-standard SRM
repairs are known to exist in this area of the doorstops and corners.
The commenter indicates that obtaining approval for such repairs prior
to further flight will be time consuming and will result in an
unwarranted, extended groundtime for affected airplanes. The commenter
believes that its recommendation will ensure that an equivalent level
of safety is maintained while minimizing the operational impact to
operators. The commenter adds that this will allow ample time to
document and submit the repair to the manufacturer for a damage
tolerance review and subsequent approval by the FAA.
The FAA does not concur with the commenter's request. The FAA, in
conjunction with the manufacturer, has conducted further analysis
concerning this issue. The FAA has determined that previous repairs of
the forward passenger door doorjamb that were not accomplished in
accordance with the DC-9 SRM or Service Rework Drawing, or that were
not approved by the FAA, are not considered to be FAA-approved repairs;
accomplishment of the initial LFEC inspection of the fuselage skin
adjacent to those existing repairs would not detect any crack under the
repairs.
[[Page 70007]]
Because cracking under the repairs could grow rapidly once it emerges
from under the repairs, the FAA does not consider that an acceptable
level of safety can be assured simply by determining that cracking has
not yet emerged from under the repairs. Therefore, any doorjambs that
were modified previously in accordance with non-FAA-approved repairs
must be repaired prior to further flight in accordance with a method
approved by the FAA.
Request To Revise Cost Impact Information
One commenter states that the FAA has underestimated the cost
impact of the proposed AD. The commenter indicates that the proposed
low frequency eddy current or high frequency eddy current inspection
will require a minimum of 4 work hours per airplane for setup,
accomplishment, and teardown. Additionally, the commenter believes that
the full modification will require approximately 500 to 600 work hours
per airplane.
The FAA concurs partially. The manufacturer has advised the FAA
that the modification will require approximately 30 work hours, as
estimated in the proposed AD. No change to the final rule has been made
in this regard. However, the manufacturer indicates that the eddy
current inspection will require approximately 1.5 work hours per
airplane. In light of this information, the FAA has revised the cost
impact information, below, to specify that approximately 2 work hours
per airplane will be required to accomplish the inspection, as
necessary.
Change to Service Bulletin Citation
Since the issuance of the proposed rule, the FAA has reviewed and
approved McDonnell Douglas Service Bulletin DC9-53-280, Revision 01,
dated July 30, 1998. This revision of the service bulletin is
essentially identical to the original issue, which was cited in the
proposed AD as the appropriate source of service information for
accomplishment of the actions specified in the AD. Revision 01 simply
deletes from the effectivity of the service bulletin Model MD-80 series
airplanes that are not affected. This revision also changes the lead
time for availability of kits to 150 days. This final rule has been
revised to include Revision 01 of the service bulletin as an additional
source of service information.
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 1,001 airplanes of the affected design in
the worldwide fleet. The FAA estimates that 656 airplanes of U.S.
registry will be affected by this AD, that it will take approximately 1
work hour per airplane to accomplish the required visual inspection,
and that the average labor rate is $60 per work hour. Based on these
figures, the cost impact of the visual inspection of this AD on U.S.
operators is estimated to be $39,360, or $60 per airplane.
Should an operator be required to accomplish the LFEC or x-ray
inspection, it will take approximately 1 work hour per airplane to
accomplish, at an average labor rate of $60 per work hour. Based on
these figures, the cost impact of any necessary LFEC or x-ray
inspection specified in this AD on U.S. operators is estimated to be
$60 per airplane, per inspection cycle.
Should an operator be required to accomplish the HFEC inspection,
it will take approximately 2 work hours per airplane to accomplish, at
an average labor rate of $60 per work hour. Based on these figures, the
cost impact of any necessary HFEC inspection specified in this AD on
U.S. operators is estimated to be $120 per airplane, per inspection
cycle.
Should an operator be required to accomplish the modification, it
will take approximately 30 work hours per airplane to accomplish, at an
average labor rate of $60 per work hour. Required parts will cost
approximately between $490 and $1,775 per airplane, depending on the
service kit purchased. Based on these figures, the cost impact of any
necessary modification specified in this AD on U.S. operators is
estimated to be between $2,290 and $3,575 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:
98-26-09 McDonnell Douglas: Amendment 39-10949. Docket 98-NM-06-AD.
Applicability: Model DC-9-10, -20, -30, -40, and -50 series
airplanes, and C-9 (military) airplanes, as listed in McDonnell
Douglas Service Bulletin DC9-53-280, Revision 01, dated July 30,
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 (g) of
this AD. The request should include an assessment of
[[Page 70008]]
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 fatigue cracking in the doorstops and
corners of the doorjamb of the forward passenger door, which could
result in rapid decompression of the fuselage and consequent reduced
structural integrity of the airplane, accomplish the following:
Note 2: Where there are differences between the service bulletin
and the AD, the AD prevails.
Note 3: The words ``repair'' and ``modify/modification'' in this
AD and the referenced service bulletin are used interchangeably.
(a) Prior to the accumulation of 48,000 total landings, or
within 3,575 landings after the effective date of this AD, whichever
occurs later, perform a one-time visual inspection to determine if
the doorstops and corners of the forward passenger door doorjamb
have been modified. Perform the inspection in accordance with
McDonnell Douglas Service Bulletin DC9-53-280, dated December 1,
1997, or Revision 01, dated July 30, 1998,
(b) For airplanes identified as Group 1 in McDonnell Douglas
Service Bulletin DC9-53-280, Revision 01, dated July 30, 1998: If
the visual inspection required by paragraph (a) of this AD reveals
that the doorstops and corners of the forward passenger door
doorjamb have not been modified, prior to further flight, perform a
low frequency eddy current (LFEC) or x-ray inspection to detect
cracks at all corners and doorstops of the forward passenger door
doorjamb, in accordance with McDonnell Douglas Service Bulletin DC9-
53-280, dated December 1, 1997, or Revision 01, dated July 30, 1998.
(1) Group 1, Condition 1. If no crack is detected during any
LFEC or x-ray inspection required by paragraph (b) of this AD,
accomplish the requirements of either paragraph (b)(1)(i) or
(b)(1)(ii) of this AD, in accordance with the service bulletin.
(i) Option 1. Repeat the LFEC inspection required by this
paragraph thereafter at intervals not to exceed 3,575 landings, or
the x-ray inspection required by this paragraph thereafter at
intervals not to exceed 3,075 landings; or
(ii) Option 2. Prior to further flight, modify the doorstops and
corners of the forward passenger door doorjamb, in accordance with
the service bulletin. Prior to the accumulation of 28,000 landings
after accomplishment of the modification, perform a high frequency
eddy current (HFEC) inspection to detect cracks on the skin adjacent
to the modification, in accordance with the service bulletin.
(A) If no crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph
(b)(1)(ii) of this AD, repeat the HFEC inspection thereafter at
intervals not to exceed 20,000 landings.
(B) If any crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph
(b)(1)(ii) of this AD, prior to further flight, repair it in
accordance with a method approved by the Manager, Los Angeles
Aircraft Certification Office (ACO), FAA, Transport Airplane
Directorate.
(2) Group 1, Condition 2. If any crack is found during any LFEC
or x-ray inspection required by paragraph (b) of this AD, and the
crack is 0.50 inch or less in length: Prior to further flight,
modify the doorstops and corners of the forward passenger door
doorjamb in accordance with the service bulletin. Prior to the
accumulation of 28,000 landings after accomplishment of the
modification, perform a HFEC inspection to detect cracks on the skin
adjacent to the modification, in accordance with the service
bulletin.
(i) If no crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (b)(2)
of this AD, repeat the HFEC inspection thereafter at intervals not
to exceed 20,000 landings.
(ii) If any crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (b)(2)
of this AD, prior to further flight, repair it in accordance with a
method approved by the Manager, Los Angeles ACO.
(3) Group 1, Condition 3. If any crack is found during any LFEC
or x-ray inspection required by paragraph (b) of this AD, and the
crack is greater than 0.5 inch in length: Prior to further flight,
repair it in accordance with a method approved by the Manager, Los
Angeles ACO.
(c) Group 2, Condition 1. For airplanes identified as Group 2 in
McDonnell Douglas Service Bulletin DC9-53-280, Revision 01, dated
July 30, 1998: If the visual inspection required by paragraph (a) of
this AD reveals that the doorstops and corners of the forward
passenger door doorjamb have been modified previously in accordance
with the McDonnell Douglas DC-9 Structural Repair Manual (SRM),
using a steel doubler, accomplish either paragraph (c)(1) or (c)(2)
of this AD in accordance with McDonnell Douglas Service Bulletin
DC9-53-280, dated December 1, 1997, or Revision 01, dated July 30,
1998.
(1) Option 1. Prior to the accumulation of 28,000 landings after
accomplishment of the modification, or within 3,500 landings after
the effective date of this AD, whichever occurs later, perform a
HFEC inspection to detect cracks on the skin adjacent to the
modification, in accordance with the service bulletin.
(i) If no crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (c)(1)
of this AD, repeat the HFEC inspection thereafter at intervals not
to exceed 20,000 landings.
(ii) If any crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (c)(1)
of this AD, prior to further flight, repair it in accordance with a
method approved by the Manager, Los Angeles ACO.
(2) Option 2. Prior to further flight, modify the doorstops and
corners of the forward passenger door doorjamb in accordance with
the service bulletin. Prior to the accumulation of 28,000 landings
after the accomplishment of the modification, perform a HFEC
inspection to detect cracks on the skin adjacent to the
modification, in accordance with the service bulletin.
(i) If no crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (c)(2)
of this AD, repeat the HFEC inspection thereafter at intervals not
to exceed 20,000 landings.
(ii) If any crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (c)(2)
of this AD, prior to further flight, repair it in accordance with a
method approved by the Manager, Los Angeles ACO.
(d) Group 2, Condition 2. For airplanes identified as Group 2 in
McDonnell Douglas Service Bulletin DC9-53-280, Revision 01, dated
July 30, 1998: If the visual inspection required by paragraph (a) of
this AD reveals that the doorstops and corners of the forward
passenger door doorjamb have been modified previously in accordance
with McDonnell Douglas DC-9 SRM or Service Rework Drawing, using an
aluminum doubler, prior to the accumulation of 28,000 landings after
the accomplishment of the modification, or within 3,500 landings
after the effective date of this AD, whichever occurs later, perform
a HFEC inspection to detect cracks on the skin adjacent to the
modification, in accordance with McDonnell Douglas Service Bulletin
DC9-53-280, dated December 1, 1997, or Revision 01, dated July 30,
1998.
(1) If no crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (d) of
this AD, repeat the HFEC inspection thereafter at intervals not to
exceed 20,000 landings.
(2) If any crack is detected on the skin adjacent to the
modification during any HFEC inspection required by paragraph (d) of
this AD, prior to further flight, repair it in accordance with a
method approved by the Manager, Los Angeles ACO.
(e) Group 2, Condition 3. For airplanes identified as Group 2 in
McDonnell Douglas Service Bulletin DC9-53-280, Revision 01, dated
July 30, 1998: If the visual inspection required by paragraph (a) of
this AD reveals that the doorstops and corners of the forward
passenger door doorjamb have been modified previously, but not in
accordance with McDonnell Douglas DC9 SRM or the Service Rework
Drawing, prior to further flight, repair it in accordance with a
method approved by the Manager, Los Angeles ACO.
(f) Accomplishment of the actions required by this AD
constitutes terminating action for inspections of Principal
Structural Element (PSE) 53.09.031 (reference McDonnell Douglas
Model DC-9 Supplemental Inspection Document) required by AD 96-13-
03, amendment 39-9671.
(g) 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. 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 4: Information concerning the existence of approved
alternative methods of
[[Page 70009]]
compliance with this AD, if any, may be obtained from the Los
Angeles ACO.
(h) 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.
(i) Except as provided by paragraphs (b)(1)(ii)(B), (b)(2)(ii),
(b)(3), (c)(1)(ii), (c)(2)(ii), (d)(2), and (e) of this AD, the
actions shall be done in accordance with McDonnell Douglas Service
Bulletin DC9-53-280, dated December 1, 1997; or McDonnell Douglas
Service Bulletin DC9-53-280, Revision 01, dated July 30, 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.
(j) This amendment becomes effective on January 22, 1999.
Issued in Renton, Washington, on December 11, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-33389 Filed 12-17-98; 8:45 am]
BILLING CODE 4910-13-U