[Federal Register Volume 65, Number 166 (Friday, August 25, 2000)]
[Rules and Regulations]
[Pages 51752-51754]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-21614]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-277-AD; Amendment 39-11877; AD 2000-17-51]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-200 and -300 Series 
Airplanes Equipped with a Main Deck Cargo Door Installed in Accordance 
with Supplemental Type Certificate (STC) SA2969SO

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting airworthiness directive (AD) 2000-17-51 that was sent 
previously to all known U.S. owners and operators of certain Boeing 
Model 737-200 and -300 series airplanes by individual notices. This AD 
supersedes an existing AD to require a one-time inspection to detect 
cracks of the lower frames and reinforcing angles of the main deck 
cargo door where the door latch fittings attach between certain 
fuselage stations and water lines, and replacement of any cracked part 
with a new part having the same part number. This action is prompted by 
reports that, during the inspections required by the existing AD, 
cracks were found in the reinforcing angles of the main deck cargo door 
frame. The actions specified by this AD are intended to detect and 
correct cracking of the lower portion of the main deck cargo door 
frames, which could result in sudden depressurization, loss or opening 
of the main deck cargo door during flight, and loss of control of the 
airplane.

DATES: Effective August 30, 2000, to all persons except those persons 
to whom it was made immediately effective by emergency AD 2000-17-51, 
issued on August 14, 2000, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 30, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before October 24, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-

[[Page 51753]]

277-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. Comments may be 
submitted via fax to (425) 227-1232. Comments may also be sent via the 
Internet using the following address: [email protected]. 
Comments sent via fax or the Internet must contain ``Docket No. 2000-
NM-277-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 applicable service information may be obtained from Pemco World 
Air Services, 100 Pemco Drive, Dothan, AL 36303. This information may 
be examined at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the FAA, Atlanta Aircraft 
Certification Office, One Crown Center, 1895 Phoenix Boulevard, Suite 
450, Atlanta, Georgia 30349; or at the Office of the Federal Register, 
800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Rany Azzi, Aerospace Engineer, 
Airframe and Propulsion Branch, ACE-117A, FAA, Atlanta Aircraft 
Certification Office, One Crown Center, 1895 Phoenix Boulevard, Suite 
450, Atlanta, Georgia 30337-2748, telephone (770) 703-6083; fax (770) 
703-6097.

SUPPLEMENTARY INFORMATION: On July 13, 2000, the FAA issued AD 2000-13-
51, amendment 39-11826 (65 FR 44977, July 20, 2000), applicable to 
certain Boeing Model 737-200 and -300 series airplanes. That AD 
requires repetitive special detailed inspections to detect cracking of 
the main deck cargo door frames, their existing reinforcing angles 
(where applicable), and the attach holes of the latch fittings between 
frame station (FS) 361.87 and FS 498.12, and between water line (WL) 
202.35 and WL 213.00, in the area where the main deck cargo door latch 
fittings attach to the frames; and corrective actions, if necessary. 
That action was prompted by a report indicating that three of the 
subject airplanes had multiple cracks in the lower portion of the main 
deck cargo door frames and, in some cases, the reinforcing angles. The 
actions required by that AD are intended to detect and correct cracking 
of the lower portion of the main deck cargo door frames, which could 
result in sudden depressurization, loss or opening of the main deck 
cargo door during flight, and loss of control of the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 2000-13-51, the FAA has received reports 
that, during the special detailed inspections (i.e., borescope) 
required by that AD, cracks were found in the reinforcing angles of the 
main deck cargo door frame. Subsequent disassembly of the affected 
structure revealed substantial cracking that was hidden by the layered 
structure and not detected by the special detailed inspections. These 
findings are a clear indication of multiple element damage (MED). MED 
is a source of widespread fatigue damage (WFD), which is characterized 
by the simultaneous presence of cracks in multiple structural details 
that are of sufficient size and density, whereby the structure will no 
longer meet its damage tolerance requirements. Therefore, the FAA has 
determined that a high frequency eddy current (HFEC) inspection of all 
affected structural elements of the main deck cargo door, and 
replacement of any cracked part with a new part having the same part 
number are necessary to prevent reduced structural integrity of the 
main deck cargo door, which could result in sudden depressurization, 
loss or opening of the main deck cargo door during flight, and loss of 
control of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Pemco Service Bulletin 737-52-
0037, including Attachment 1, dated August 10, 2000. The service 
bulletin describes procedures for an HFEC inspection to detect cracks 
of the lower frames and reinforcing angles of the main deck cargo door 
where the door latch fittings attach between FS 361.87 and FS 498.12 
and WL 202.35 and WL 213.00, and replacement of any cracked part with a 
new part having the same part number.

Explanation of Requirements of the Rule

    Since the unsafe condition described is likely to exist or develop 
on other airplanes of the same type design, the FAA issued emergency AD 
2000-17-51 to detect and correct cracking of the lower portion of the 
main deck cargo door frames, which could result in sudden 
depressurization, loss or opening of the main deck cargo door during 
flight, and loss of control of the airplane. The AD supersedes AD 2000-
13-51 to require a one-time HFEC inspection to detect cracks of the 
lower frames and reinforcing angles of the main deck cargo door where 
the door latch fittings attach between FS 361.87 and FS 498.12 and WL 
202.35 and WL 213.00, and replacement of any cracked part with a new 
part having the same part number. The actions are required to be 
accomplished in accordance with the service bulletin previously 
described.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual notices 
issued on August 14, 2000, to all known U.S. owners and operators of 
certain Boeing Model 737-200 and -300 series airplanes. These 
conditions still exist, and the AD is hereby published in the Federal 
Register as an amendment to section 39.13 of the Federal Aviation 
Regulations (14 CFR 39.13) to make it effective to all persons.

Interim Action

    The FAA is considering further rulemaking action to supersede this 
AD to require replacement of the main deck cargo door frames and 
reinforcing angles that have accumulated 7,000 or more total flight 
cycles with new parts. However, the planned compliance time for these 
actions is sufficiently long so that prior notice and time for public 
comment will be practicable.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that

[[Page 51754]]

summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-277-AD.'' The postcard will be date stamped 
and returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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 removing amendment 39-11826 (65 FR 
44977, July 20, 2000), and by adding a new airworthiness directive 
(AD), amendment 39-11877, to read as follows:

2000-17-51  Boeing: Amendment 39-11877. Docket 2000-NM-277-AD. 
Supersedes AD 2000-13-51, Amendment 39-11826.
    Applicability: Model 737-200 and -300 series airplanes equipped 
with a main deck cargo door installed in accordance with 
Supplemental Type Certificate (STC) SA2969SO, certificated in any 
category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (b) 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 lower portion of the main 
deck cargo door frames, which could result in sudden 
depressurization, loss or opening of the main deck cargo door during 
flight, and loss of control of the airplane, accomplish the 
following:

One-Time Inspection and Corrective Action, If Necessary

    (a) Within 7 days after the effective date of this AD, perform a 
one-time high frequency eddy current inspection to detect cracks of 
the lower frames and reinforcing angles of the main deck cargo door 
where the door latch fittings attach between fuselage station (FS) 
361.87 and FS 498.12 and water line (WL) 202.35 and WL 213.00, in 
accordance with the inspection procedures specified in paragraph 
3.D.(1) of the Accomplishment Instructions of Pemco Service Bulletin 
737-52-0037, including Attachment 1, dated August 10, 2000. If any 
crack is detected, prior to further flight, replace the cracked part 
with a new part having the same part number, in accordance with 
paragraph 3.D.(2) of the Accomplishment Instructions of the service 
bulletin.

Alternative Methods of Compliance

    (b) 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, Atlanta Aircraft Certification 
Office (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, Atlanta ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.

Special Flight Permits

    (c) 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.

Incorporation by Reference

    (d) The actions shall be done in accordance with Pemco Service 
Bulletin 737-52-0037, including Attachment 1, dated August 10, 2000. 
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 Pemco World Air Services, 100 Pemco 
Drive, Dothan, AL 36303. Copies may be inspected at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Atlanta Aircraft Certification Office, 
One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, 
Georgia; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

Effective Date

    (e) This amendment becomes effective on August 30, 2000, to all 
persons except those persons to whom it was made immediately 
effective by emergency AD 2000-17-51, issued on August 14, 2000, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on August 18, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-21614 Filed 8-24-00; 8:45 am]
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