[Federal Register Volume 59, Number 43 (Friday, March 4, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4447]


[[Page Unknown]]

[Federal Register: March 4, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-86-AD; Amendment 39-8844; AD 94-05-06]

 

Airworthiness Directives; McDonnell Douglas Model MD-11 Series 
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 MD-11 series airplanes, 
that requires modification or replacement of designated passenger cabin 
floor panels. This amendment is prompted by a report that, during 
manufacture, the inserts that attach the floor panels to the seat 
tracks and floor beams were installed using sealant rather than 
required adhesive. The actions specified by this AD are intended to 
prevent loss of the passenger cabin floor capability to support the 
airplane interior inertia loads under emergency landing conditions.

DATES: Effective April 4, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 4, 1994.

ADDRESSES: The service information referenced in this AD may be 
obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, 
California 90801-1771, Attention: Business Unit Manager, Technical 
Administrative Support, Dept. L51, M.C. 2-98. 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, Los Angeles Aircraft Certification Office, 
3229 East Spring Street, Long Beach, 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-121L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3229 East Spring Street, Long 
Beach, California 90806-2425; telephone (310) 988-5324; fax (310) 988-
5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations to include an airworthiness directive (AD) that is 
applicable to certain McDonnell Douglas Model MD-11 series airplanes 
was published in the Federal Register on August 19, 1993 (58 FR 44150). 
That action proposed to require modification or replacement of 
designated passenger cabin floor panels.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    Two commenters support the proposed rule.
    The Air Transport Association (ATA) of America, on behalf of 
several of its members, requests that the FAA withdraw the proposed 
rule. The commenter states that all U.S. operators and all but one non-
U.S. operator have accomplished the modification or replacement 
specified in McDonnell Douglas MD-11 Service Bulletin 53-31, which is 
cited in the proposed rule, thereby ensuring that 9g crash 
certification requirements are satisfied. The commenter adds that 
McDonnell Douglas MD-11 Service Bulletins 53-32 and 53-33, which are 
also cited in the proposal, were only included in the manufacturer's 
service program to ensure commonality between operators, but were not 
included in that program to return the aircraft to its original design 
intent. The commenter concludes that, since all U.S. operators have 
accomplished the actions described in McDonnell Douglas MD-11 Service 
Bulletin 53-31, there is no need for an AD. Further, the commenter 
believes that issuance of the AD would contradict the principles of 
Presidential Executive Order 12866 (Regulatory Planning and Review), 
and would cause an unjustifiable expense to operators.
    The FAA does not concur with the commenter's request to withdraw 
the proposed rule. As explained in the preamble to the proposal, the 
FAA has determined that accomplishment of the modification or 
replacement described in McDonnell Douglas MD-11 Service Bulletin 53-31 
is necessary to correct an unsafe condition described as loss of the 
passenger cabin floor capability to support the airplane interior 
inertia loads under emergency landing conditions. Under existing 
bilateral airworthiness agreements, the FAA is obligated, through the 
AD process, to advise foreign airworthiness authorities of unsafe 
conditions relating to products produced in the United States, and to 
provide instructions determined necessary to correct the unsafe 
condition addressed. The appropriate vehicle for mandating such action 
to correct an unsafe condition is the airworthiness directive.
    However, upon consideration of data submitted by the manufacturer 
since issuance of the proposal, the FAA has determined that 
accomplishment of the modification or replacement specified in 
McDonnell Douglas MD-11 Service Bulletin 53-31 adequately addresses the 
unsafe condition, and that the actions described in McDonnell Douglas 
MD-11 Service Bulletins 53-32 and 53-33 are not necessary to address 
that unsafe condition. The FAA's original concern was that 
interchanging the floor panels could result in an unsafe condition 
under emergency landing conditions. However, based on the data received 
from the manufacturer, the FAA finds that its concern regarding floor 
panel interchangeability is addressed by part number controls; original 
panels are not interchangeable with reworked panels or new panels. In 
light of this, the FAA has removed paragraphs (b) and (c) from the 
final rule. In addition, references to McDonnell Douglas MD-11 Service 
Bulletins 53-32 and 53-33 have been removed from the applicability of 
the AD. The FAA also has revised the economic impact paragraph, below, 
to reflect the fact that all U.S. airplanes have accomplished the 
requirements of this AD.
    One commenter requests that paragraph (a) of the proposed rule be 
revised to clarify that each individual panel may be reworked in 
accordance with Option I of McDonnell Douglas MD-11 Service Bulletin 
53-31, or replaced in accordance with Option II of that service 
bulletin, rather than implying that all panels must be either reworked 
or replaced. The commenter also requests that the proposal be revised 
to indicate that installation of operator-manufactured panels with 
properly installed inserts are acceptable in lieu of production panels.
    The FAA concurs. Paragraph (a) of this AD has been revised to 
indicate that the requirements of that paragraph may be accomplished by 
either reworking an individual panel in accordance with Option I of the 
service bulletin, or replacing an individual panel in accordance with 
Option II of the service bulletin. Paragraph (a) of the final rule also 
has been revised to specify that new panels that meet the original type 
design or FAA-approved equivalent panels are considered acceptable 
replacement panels.
    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.
    There are approximately 32 Model MD-11 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 20 
airplanes of U.S. registry will be affected by this AD. The FAA has 
been advised that the requirements of this AD have been accomplished on 
all 20 airplanes of U.S. registry.
    However, should an affected airplane be imported and placed on the 
U.S. Register in the future, the FAA has been advised that the 
manufacturer plans to provide required parts and to accomplish the 
required modification at no expense to operators. Therefore, there is 
no future economic cost impact of this rule on U.S. operators.
    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 14 CFR part 
39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

94-05-06 McDonnell Douglas: Amendment 39-8844. Docket 93-NM-68-AD.

    Applicability: Model MD-11 series airplanes, as listed in 
McDonnell Douglas MD-11 Service Bulletin 53-31, dated January 29, 
1993; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent loss of the passenger cabin floor capability to 
support the airplane interior inertia loads under emergency landing 
conditions, accomplish the following:
    (a) Within one year after the effective date of this AD, modify 
or replace the passenger cabin floor panels designated in McDonnell 
Douglas MD-11 Service Bulletin 53-31, dated January 29, 1993, in 
accordance with that service bulletin. The requirements of this 
paragraph may be accomplished by either reworking an individual 
panel in accordance with Option I of the service bulletin, or 
replacing an individual panel in accordance with Option II of the 
service bulletin. New panels that meet the original type design or 
FAA-approved equivalent panels are considered to be acceptable 
replacement panels.
    (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 Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate. 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: 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 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (d) The modification or replacement shall be done in accordance 
with McDonnell Douglas MD-11 Service Bulletin 53-31, dated January 
29, 1993. 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, P.O. Box 1771, Long Beach, California 90801-1771, 
Attention: Business Unit Manager, Technical Administrative Support, 
Dept. L51, M.C. 2-98. Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 
at the FAA, Los Angeles Aircraft Certification Office, 3229 East 
Spring Street, Long Beach, 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 4, 1994.

    Issued in Renton, Washington, on February 22, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-4447 Filed 3-3-94; 8:45 am]
BILLING CODE 4910-13-U