[Federal Register Volume 65, Number 66 (Wednesday, April 5, 2000)]
[Proposed Rules]
[Pages 17818-17821]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8387]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-333-AD]
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: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain McDonnell Douglas 
Model DC-9-10, -20, -30, -40, and -50 series airplanes and C-9 
(military) airplanes, that currently 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 action 
would require a reduction in the inspection threshold and repetitive 
intervals for a certain doubler configuration and an increase in the 
repetitive inspection interval for a certain other doubler 
configuration. This proposal is prompted by a determination that 
certain inspection compliance times were incorrect. The actions 
specified by the proposed AD are intended to detect and correct fatigue 
cracking, which could result in rapid decompression of the fuselage and 
consequent reduced structural integrity of the airplane.

DATES: Comments must be received by May 22, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-

[[Page 17819]]

333-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 Boeing Commercial Aircraft Group, Long Beach 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 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: 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:

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.
    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 99-NM-333-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. 99-NM-333-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On December 11, 1998, the FAA issued AD 98-26-09, amendment 39-
10949 (63 FR 70005, December 18, 1998), applicable to certain McDonnell 
Douglas Model DC-9-10, -20, -30, -40, and -50 series airplanes and C-9 
(military) airplanes, 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. That action was 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 requirements of that 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.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, the manufacturer has informed the 
FAA that the initial and repetitive inspection compliance times were 
incorrect in McDonnell Douglas Service Bulletin DC9-53-280, Revision 
01, dated July 30, 1998, for the doorstops and corners of the forward 
passenger doorjamb that have been modified previously, using steel 
doublers. Therefore, McDonnell Douglas has issued Service Bulletin DC9-
53-280, Revision 02, dated July 26, 1999, to correct this condition. 
Paragraph (c)(1) of the existing AD specifies that the high frequency 
eddy current (HFEC) initial inspection should be performed ``Prior to 
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. * * *'' The correct initial HFEC inspection 
compliance time should be 6,000 landings after accomplishment of the 
modification, or within 3,575 landings after the effective date of the 
AD, whichever occurs later.
    Also, paragraph (c)(1)(i) of AD 98-26-09 specifies that the HFEC 
repetitive inspection interval is 20,000 landings. The correct 
repetitive HFEC inspection interval is 3,000 landings.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletin DC-9-53-280, Revision 02, dated July 26, 1999, which describes 
procedures for the following:
    1. Performing a one-time visual inspection to determine if the 
doorstops and corners of the forward passenger door doorjamb have been 
modified;
    2. For certain airplanes: Performing a low frequency eddy current 
(LFEC) or x-ray inspection to detect cracks at all corners and 
doorstops of the doorjamb of the forward passenger door;
    3. For certain other airplanes: Performing an HFEC inspection to 
detect cracks on the skin adjacent to the modification;
    4. Conducting repetitive inspections, or modifying the doorstops 
and corners of the doorjamb of the forward passenger door, and 
performing follow-on HFEC inspections, if no cracking is detected;
    5. Performing repetitive HFEC inspections to detect cracks on the 
skin adjacent to any doorstop or corner that has been modified; and
    6. Modifying doorstops and corners if any crack is found to be 0.5 
inch or less in length at all doorstops and corners that have not been 
modified, and performing follow-on repetitive HFEC inspections.
    Accomplishment of the action 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 supersede AD 98-26-09, amendment 39-10949, to require 
accomplishment of the actions specified in the service bulletin 
described previously, except as discussed below.
    The FAA has also noted that a typographical error exists in 
paragraph (d) of AD 98-26-09 that involves the compliance time for 
performing an HFEC inspection to detect cracks in the skin adjacent to 
a certain modification of the doorstops and corners of the forward 
passenger door doorjamb. That AD specifies that the HFEC inspection 
should be performed ``Prior to the accumulation of 28,000 landings 
since accomplishment of that modification, or within 3,500 landings 
after the effective date of this AD, whichever occurs later.'' However, 
the intent of the FAA was to specify that compliance time as

[[Page 17820]]

``Prior to the accumulation of 28,000 landings since accomplishment of 
that modification, or within 3,575 landings after the effective date of 
this AD, whichever occurs later.'' Paragraph (d) of this proposed AD 
has been revised to correctly specify 3,575 landings.

Differences Between Proposed Rule and Service Bulletin

    Operators should note that, although the service bulletin specifies 
that the manufacturer must be contacted for disposition of certain 
conditions, this proposal would require the repair of those conditions 
to be accomplished in accordance with a method approved by the FAA.

Cost Impact

    There are approximately 809 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 572 airplanes of U.S. registry 
would be affected by this proposed AD.
    The visual inspection that is currently required by AD 98-26-09 and 
that is retained in this AD takes approximately 1 work hour per 
airplane to accomplish the proposed visual inspection, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the currently required visual inspection proposed by this AD 
on U.S. operators is estimated to be $34,320 or $60 per airplane.
    Should an operator be required to accomplish the proposed LFEC or 
x-ray inspection, it would 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 proposed by this AD on U.S. operators is estimated to be 
$120 per airplane, per inspection cycle.
    Should an operator be required to accomplish the proposed HFEC 
inspection, it would 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 
proposed by this AD on U.S. operators is estimated to be $60 per 
airplane, per inspection cycle.
    Should an operator be required to accomplish the proposed 
modification, it would take approximately 8 work hours per airplane to 
accomplish, at an average labor rate of $60 per work hour. Required 
parts would cost between $898 and $1,037 per airplane, depending on the 
service kit purchased. Based on these figures, the cost impact of the 
modification proposed by this AD on U.S. operators is estimated to be 
between $1,378 and $1,517 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or 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 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 removing amendment 98-26-09, 
amendment 39-10949 (63 FR 70005, December 18, 1998), and by adding a 
new airworthiness directive (AD), to read as follows:

McDonnell Douglas: Docket 99-NM-333-AD. Supersedes AD 98-26-09, 
Amendment 39-10949.

    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 02, dated July 26, 
1999, 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)(1) 
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 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.

Visual Inspection

    (a) Prior to the accumulation of 48,000 total landings, or 
within 3,575 landings after January 22, 1999 (the effective date of 
AD 98-26-09, amendment 39-10949), 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, Revision 01, dated July 30, 
1998, or Revision 02, dated July 26, 1999.

Group 1, Low Frequency Eddy Current Inspection

    (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, Revision 01, dated July 30, 1998, or 
Revision 02, dated July 26, 1999.
    (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.

[[Page 17821]]

    (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 an 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 an 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.

Group 2, Inspection of Door Corners With Steel Doublers

    (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, Revision 01, dated July 30, 
1998, or Revision 02, dated July 26, 1999.
    (1) Option 1. Prior to the accumulation of 6,000 landings after 
accomplishment of the modification, or within 3,575 landings after 
January 22, 1999, or within 2,000 landings after the effective date 
of this AD, whichever occurs latest: Perform an 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 within 2,000 landings after 
the effective date of this AD or within 3,000 landings from the last 
inspection in accordance with paragraph (c)(1) of this AD, whichever 
occurs later, and thereafter at intervals not to exceed 3,000 
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.

Group 2, Inspection of Door Corners With Aluminum Doublers

    (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 3,575 landings 
after January 22, 1999, whichever occurs later, perform an 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, Revision 01, dated July 30, 
1998, or Revision 02, dated July 26, 1999.
    (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.

Group 2, Inspection of Door Corners With Non-SRM Modifications

    (e) Group 2, Condition 3. For airplanes identified as Group 2 in 
McDonnell Douglas Service Bulletin DC9-53-280, Revision 02, dated 
July 26, 1999: 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.

Terminating Action for Supplemental Inspection Document, AD 96-13-03

    (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.

Alternative Methods of Compliance

    (g)(1) 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.
    (2) Alternative methods of compliance, approved previously in 
accordance with AD 98-26-09, amendment 39-10949, or AD 96-13-03, 
amendment 39-9671, are approved as alternative methods of compliance 
with this AD.

    Note 4: 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

    (h) 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.

    Issued in Renton, Washington, on March 30, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-8387 Filed 4-4-00; 8:45 am]
BILLING CODE 4910-13-U