[Federal Register Volume 63, Number 180 (Thursday, September 17, 1998)]
[Proposed Rules]
[Pages 49679-49681]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-24869]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-227-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model MD-11 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 Model 
MD-11 series airplanes. This proposal would require inspections to 
detect attachment failures of the 12 attachments located on the No. 4 
banjo fitting/pylon carry-through cap, and to detect cracking of the 
forward and aft flanges and bolt holes of the No. 4 banjo fitting; 
repair, if necessary; and replacement of the 12 attachments with new or 
serviceable parts. Such replacement would terminate the repetitive 
inspections. This proposal is prompted by a report indicating that 
attachment bolts on the forward and aft flanges of the No. 4 banjo 
fitting and the pylon carry-through cap failed due to fatigue cracking. 
The actions specified by the proposed AD are intended to prevent such 
cracking, which could result in reduced controllability of the airplane 
during flight and ground operations.

DATES: Comments must be received by November 2, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 96-NM-227-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.
    The service information referenced in the proposed rule may be 
obtained from The Boeing Company, Douglas Products Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Technical 
Publications Business Administration, Department C1-L51 (2-60). This 
information may be examined 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.

FOR FURTHER INFORMATION CONTACT: John L. Cecil, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712; telephone (562) 627-5229; 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 notice may be changed in 
light of the comments received.
    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.

[[Page 49680]]

    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 96-NM-227-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. 96-NM-227-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that attachment bolts on 
the forward and aft flanges of the No. 4 banjo fitting and the pylon 
carry-through cap had failed on McDonnell Douglas Model MD-11 series 
airplanes. Investigation revealed that the steel attachment bolts had 
failed due to fatigue cracking. In addition, another report indicated 
that a 20-mm long crack in the forward flange of the No. 4 banjo 
fitting of the lower vertical stabilizer also had been detected. That 
airplane had accumulated 4,949 flight cycles and had logged 24,282 
flight hours.
    Fatigue cracking of the attachment bolts of the No. 4 banjo 
fittings, if not detected and corrected in a timely manner, could cause 
cracking of the flanges; such cracking, if not prevented, could result 
in reduced controllability of the airplane during flight and ground 
operations.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas MD-11 Service 
Bulletin 55-13, dated December 22, 1992, and Revision 1, dated December 
17, 1993; and McDonnell Douglas Service Bulletin MD-11-55-013, Revision 
02, dated October 28, 1996, and Revision 03, dated May 15, 1998; which 
are described as follows:
     The original issue of the service bulletin describes 
procedures for replacement of the 12 attachment bolts located on the 
No. 4 banjo fitting/pylon carry-through cap with improved attachment 
bolts. These improved bolts are made from a higher strength and more 
corrosion resistant material. Replacement of the existing bolts with 
the improved bolts will minimize the possibility of attachment 
failures.
     Revision 1 of the service bulletin adds an eddy current 
inspection to detect cracking of both the forward and aft flanges and 
of the bolt holes of the No. 4 banjo fitting, and replacement of the 
attachment bolts with a new or serviceable attachment bolts, if 
necessary. Revision 1 also adds airplanes to the effectivity of the 
original issue of the service bulletin.
     Revision 02 of the service bulletin adds procedures for 
repetitive visual inspections to detect any discrepancies of the 12 
attachments bolts located on the No. 4 banjo fitting/pylon carry-
through cap, and repair, if necessary.
     Revision 03 of the service bulletin specifies revised part 
numbers of second oversize Hi-Lok attachments. Revision 03 also 
specifies certain conditions for which additional work may or may not 
be necessary.
    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 accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletin

    Operators should note that the service bulletin specifies that the 
manufacturer may be contacted if holes require enlargement beyond 
certain specifications, or for an evaluation for deferment of certain 
repairs. However, this proposal would require disposition of those 
conditions to be accomplished in accordance with a method approved by 
the FAA.

Cost Impact

    There are approximately 82 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 31 airplanes of U.S. registry 
would be affected by this proposed AD.
    The FAA estimates that it would take approximately 1 work hour per 
airplane to accomplish the proposed external visual inspection, and 
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 $1,860, or $60 per airplane, per inspection cycle.
    The FAA estimates that it would take approximately 2 work hours per 
airplane to accomplish the proposed eddy current inspection, and 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 
$3,720, or $120 per airplane.
    The FAA estimates that it would take approximately 6 work hours per 
airplane to accomplish the proposed replacement, and that the average 
labor rate is $60 per work hour. Required parts would cost 
approximately $250 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be $18,910, 
or $610 per airplane.
    The cost impact figures discussed above are 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 AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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 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:


[[Page 49681]]


    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 96-NM-227-AD.

    Applicability: Model MD-11 series airplanes; as listed in 
McDonnell Douglas Service Bulletin MD11-55-013, Revision 03, dated 
May 15, 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 (e) 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 failure of the attachment bolts on the forward and 
aft flanges of the No. 4 banjo fitting and the pylon carry-through 
cap due to fatigue cracking, and consequent reduced controllability 
of the airplane during flight and ground operation, accomplish the 
following:
    (a) Within 1,500 landings after the effective date of this AD, 
perform an external visual inspection for attachment failures of the 
12 attachments located on the No. 4 banjo fitting/pylon carry-
through cap, in accordance with McDonnell Douglas Service Bulletin 
MD11-55-013, Revision 02, dated October 28, 1996; or Revision 03, 
dated May 15, 1998.
    (1) If no failed attachment is found, repeat the external visual 
inspection thereafter at intervals not to exceed 1,500 landings 
until the terminating action specified in paragraph (b) of this AD 
is accomplished.
    (2) If any failed attachment is found, prior to further flight, 
accomplish the actions specified in paragraph (b) of this AD.
    (b) Except as provided by paragraph (c) of this AD: Within 5 
years after the effective date of this AD, perform an eddy 
inspection to detect cracking of the forward and aft flanges and 
bolt holes of the No. 4 banjo fitting, in accordance with McDonnell 
Douglas MD-11 Service Bulletin 55-13, Revision 1, dated December 17, 
1993; or McDonnell Douglas Service Bulletin MD11-55-013, Revision 
02, dated October 28, 1996; or McDonnell Douglas Service Bulletin 
MD11-55-013, Revision 03, dated May 15, 1998.
    (1) If no cracking is found, within 5 years after the effective 
date of this AD, replace the 12 attachments located on the No. 4 
banjo fitting/pylon carry-through cap with new or serviceable 
attachments in accordance with Revision 03 of the service bulletin. 
Such replacement constitutes terminating action for the repetitive 
inspections required by paragraph (a) of this AD.
    (2) If any cracking is found, prior to further flight, repair 
the fitting, and replace the 12 attachments located on the No. 4 
banjo fitting/pylon carry-through cap with new or serviceable 
attachments in accordance with Revision 03 of the service bulletin. 
Such replacement constitutes terminating for the repetitive 
inspections required by paragraph (a) of this AD.
    (c) For airplanes on which McDonnell Douglas MD-11 Service 
Bulletin 55-13, dated December 22, 1992, has been accomplished, and 
on which no failed attachment was found during the inspection 
required by paragraph (a) of this AD: The eddy current bolt hole 
inspection specified in paragraph (b) of this AD is not required 
provided that all 12 attachments have been replaced in accordance 
with the original issue of the service bulletin.
    (d) If the service bulletin specifies that the manufacturer may 
be contacted for disposition of enlargement of holes beyond the 
specifications of the service bulletin, or for an evaluation for 
deferment of repairs: Those conditions shall be addressed in 
accordance with a method approved by the Manager, Los Angeles 
Aircraft Certification Office (ACO), FAA, Transport Airplane 
Directorate.
    (e) 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (f) 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.

    Issued in Renton, Washington, on September 10, 1998.
Dorenda D. Baker,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-24869 Filed 9-16-98; 8:45 am]
BILLING CODE 4910-13-U