[Federal Register Volume 61, Number 70 (Wednesday, April 10, 1996)]
[Rules and Regulations]
[Pages 15882-15884]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-8583]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-55-AD; Amendment 39-9562; AD 96-07-51]


Airworthiness Directives; McDonnell Douglas Model DC-9 Series 
Airplanes

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) T96-07-51 that was sent 
previously to all known U.S. owners and operators of McDonnell Douglas 
Model DC-9 series airplanes by individual telegrams. This AD requires 
repetitive inspections to detect corrosion and cracking of the fuselage 
upper skin and frames in the area of the loop antenna assemblies of the 
automatic direction finder (ADF), and repair, if necessary. This 
amendment is prompted by reports of severe corrosion and cracking found 
in that area. The actions specified by this AD are intended to prevent 
rapid decompression of the fuselage, significant structural damage, and 
subsequent reduced structural integrity of the airplane, due to 
problems associated with corrosion and fatigue cracking in the subject 
area.

DATES: Effective April 15, 1996, to all persons except those persons to 
whom it was made immediately effective by telegraphic AD T96-07-51, 
issued March 22, 1996, 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 April 15, 1996.
    Comments for inclusion in the Rules Docket must be received on or 
before June 10, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-56-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The applicable service information may be obtained from McDonnell 
Douglas Corporation, 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, Los Angeles Aircraft Certification Office, Transport Airplane 
Directorate, 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; telephone (310) 627-5324; fax (310) 627-
5210.

SUPPLEMENTARY INFORMATION: On March 22, 1996, the FAA issued 
telegraphic AD T96-07-51, which is applicable to certain McDonnell 
Douglas Model DC-9 series airplanes. That action was prompted by a 
recent report indicating that severe corrosion and a 39-inch crack of 
the forward fuselage upper skin was found during scheduled maintenance 
on a McDonnell Douglas Model DC-9-31 series airplane. The crack 
originated under the loop antenna assemblies of the forward and aft 
automatic direction finders (ADF). Subsequent inspection of the 
adjacent structure revealed cracking of the fuselage frame at fuselage 
station 275. The cracking found has been attributed to fatigue. 
Corrosion and fatigue cracking in these areas, if not detected and 
corrected in a timely manner, could result in rapid decompression of 
the fuselage, significant damage to adjacent structure, and subsequent 
reduced structural integrity of the airplane.
    The FAA has reviewed and approved McDonnell Douglas Alert Service 
Bulletin DC9-53A282, dated March 20, 1996, which describes procedures 
for repetitive internal visual inspections to detect corrosion and 
cracking of the fuselage forward upper skin, and to detect cracking of 
the fuselage frames in the area of the loop antenna assemblies of the 
forward and aft ADF. This alert service bulletin refers to the DC-9 
Structural Repair Manual (SRM) for procedures to repair certain 
corrosion or cracking.
    Since the unsafe condition described is likely to exist or develop 
on other airplanes of the same type design, the FAA issued Telegraphic 
AD T96-07-51 to prevent rapid decompression of the fuselage, 
significant structural damage, and subsequent reduced structural 
integrity of the airplane, due to problems associated with corrosion 
and fatigue cracking in the area of the loop antenna assemblies of the 
forward and aft ADF. The AD requires repetitive internal visual 
inspections to detect corrosion and cracking of the fuselage

[[Page 15883]]
forward upper skin and to detect cracking of the fuselage frames in the 
subject area. This AD also requires repair of any corrosion or cracking 
found. The inspections are required to be accomplished in accordance 
with the alert service bulletin described previously. If cracking or 
corrosion that is found that is within specified limits, it is required 
to be repaired in accordance with the DC-9 SRM. However, if corrosion 
or cracking is found that is outside specified limits, it is required 
to be repaired in accordance with a method approved by the FAA.
    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 telegrams 
issued on March 22, 1996, to all known U.S. owners and operators of 
McDonnell Douglas Model DC-9 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.
    This is considered to be interim action. The manufacturer has 
advised that it is currently developing a modification that will 
positively address the unsafe condition identified by this AD. Once 
this modification is developed, approved, and available, the FAA may 
consider further rulemaking.

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 
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 96-NM-55-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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.
    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 adding the following new 
airworthiness directive:

96-07-51  McDonnell Douglas: Amendment 39-9562. Docket 96-NM-55-AD.

    Applicability: Model DC-9 series airplanes having fuselage 
numbers 001 through 631, inclusive; 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 (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 prevent rapid decompression of the fuselage, significant 
structural damage, and subsequent reduced structural integrity of 
the airplane, due to problem associated with corrosion and fatigue 
cracking, accomplish the following:
    (a) Within 15 days after the effective date of this AD: Perform 
an internal visual inspection to detect corrosion and cracking of 
the fuselage forward upper skin and to detect cracking of the 
fuselage frame in the area of the loop antenna assemblies of the 
forward and aft automatic direction finder (ADF), in accordance with 
McDonnell Douglas Alert Service Bulletin DC9-53A282, dated March 20, 
1996.
    (1) If no corrosion or cracking is detected: Repeat the 
inspections required by paragraph (a) of this AD thereafter at 
intervals not to exceed six months.
    (2) If any corrosion or cracking is detected that is within the 
limits specified in Chapter 53-04, Figure 29, of the DC-9 Structural 
Repair Manual (SRM): Prior to further flight, repair in accordance 
with Chapter 53-04, Figure 29, of the SRM. Repeat the inspection 
required by paragraph (a) of this AD thereafter at intervals not to 
exceed six months.
    (3) If any corrosion or cracking is detected in the fuselage 
forward upper skin, or if any cracking is detected in the fuselage 
frame, and that corrosion or cracking is outside the limits 
specified in Chapter 53-04, Figure 29, of the SRM: Prior to further 
flight, repair in accordance with a method approved by the Manager, 
Los Angeles Aircraft Certification Office (ACO), FAA, Transport 
Airplane Directorate.
    (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, Los Angeles ACO, FAA, Transport 
Airplane Directorate. Operators shall submit their requests through 
an appropriate FAA Principal Maintenance Inspector, who may

[[Page 15884]]
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.
    (c) 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.
    (d) The inspections shall be done in accordance with McDonnell 
Douglas Alert Service Bulletin DC9-53A282, dated March 20, 1996. 
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 McDonnell Douglas Corporation, 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, Los Angeles Aircraft Certification Office, FAA, Transport 
Airplane Directorate, 3960 Paramount Boulevard, Lakewood, 
California; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.
    (e) This amendment becomes effective on April 15, 1996, to all 
persons except those persons to whom it was made immediately 
effective by telegraphic AD T96-07-51, issued on March 22, 1996, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on March 28, 1996.
Bill R. Boxwell,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-8583 Filed 4-9-96; 8:45 am]
BILLING CODE 4910-13-U