[Federal Register Volume 69, Number 241 (Thursday, December 16, 2004)]
[Proposed Rules]
[Pages 75277-75280]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-27512]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-19867; Directorate Identifier 2004-NM-58-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model MD-90-30 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all McDonnell Douglas Model MD-90-30 airplanes. This proposed AD 
would require replacing existing dual anti-skid control manifolds 
(DACM) with new, improved or reworked and reidentified DACMs; 
inspecting the inlet filters and other components of the DACMs for 
damage; replacing any damaged DACM components with new or serviceable 
components; and flushing/cleaning the braking system prior to replacing 
the inlet filters. This proposed AD is prompted by reports of multiple 
incidents of blown tires on landing while using maximum autobrake. We 
are proposing this AD to prevent metallic fibers from the first stage 
filter of the servo valves inside the DACM from becoming lodged in the 
first stage nozzle of the servo valve, which could lead to tire failure 
during high speed/

[[Page 75278]]

high energy braking and possible subsequent runway departure.

DATES: We must receive comments on this proposed AD by January 31, 
2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     By fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood 
Boulevard, Long Beach, California 90846, Attention: Data and Service 
Management, Dept. C1-L5A (D800-0024).
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or in person at the Docket Management Facility, 
U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-
401, on the plaza level of the Nassif Building, Washington, DC. This 
docket number is FAA-2004-19867; the directorate identifier for this 
docket is 2004-NM-58-AD.

FOR FURTHER INFORMATION CONTACT:
    Technical information: Cheyenne Del Carmen, Aerospace Engineer, 
Cabin Safety, Mechanical & Environmental Branch, ANM-150L, FAA, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; telephone (562) 627-5338; fax (562) 
627-5210.
    Plain language information: Marcia Walters, [email protected].

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

    The FAA has implemented new procedures for maintaining AD dockets 
electronically. As of May 17, 2004, new AD actions are posted on DMS 
and assigned a docket number. We track each action and assign a 
corresponding directorate identifier. The DMS AD docket number is in 
the form ``Docket No. FAA-2004-99999.'' The Transport Airplane 
Directorate identifier is in the form ``Directorate Identifier 2004-NM-
999-AD.'' Each DMS AD docket also lists the directorate identifier 
(``Old Docket Number'') as a cross-reference for searching purposes.

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2004-19867; 
Directorate Identifier 2004-NM-58-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments submitted by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You can get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the Docket

    You can examine the AD docket in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the DOT street address stated in the ADDRESSES section. 
Comments will be available in the AD docket shortly after the DMS 
receives them.

Discussion

    We have received reports of multiple incidents of blown tires on 
landing while using maximum autobrake on McDonnell Douglas Model MD-90-
30 airplanes. The reports indicate that, due to filter contamination, 
structural damage, or excessive wear, metallic fibers from the first 
stage filter of the servo valves inside the dual anti-skid control 
manifold (DACM) are becoming lodged in the first stage nozzle of the 
servo valve. This condition, if not corrected, could result in tire 
failure during high speed/high energy braking and possible subsequent 
runway departure.

Relevant Service Information

    We have reviewed McDonnell Douglas Service Bulletin MD90-32-056, 
dated October 7, 2003. The service bulletin describes procedures for 
replacing existing DACMs with new, improved or reworked and 
reidentified DACMs.
    Service Bulletin MD90-32-056 specifies prior or concurrent 
accomplishment of McDonnell Douglas Service Bulletin MD90-32-043, 
Revision 01, dated November 9, 2000.
    We have reviewed Service Bulletin MD90-32-043, which describes 
procedures for replacing the metered pressure inlet filters of the DACM 
with new filters. Service Bulletin MD90-32-043 also describes 
procedures for inspecting the inlet filters and other components of the 
DACM for damage, and flushing/cleaning the braking system prior to 
replacing the inlet filters.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.
    Service Bulletin MD90-32-056 refers to Aircraft Braking Systems 
Corporation (ABSC) Service Bulletin MD-90 6006079-32-02, dated August 
7, 2003, as an additional source of service information for reworking 
and reidentifying DACMs.
    Service Bulletin MD90-32-043 refers to ABSC Service Bulletin MD90-
32-12, dated January 12, 2000, as an additional source of service 
information for inspecting components of the DACM for cleanliness, 
structural damage, or excessive wear, and replacing any damaged 
components with new or serviceable components.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. Therefore, we are proposing this AD, which 
would require replacing DACMs with new, improved or reworked and 
reidentified DACMs;

[[Page 75279]]

inspecting the inlet filters and other components of the DACMs for 
damage; replacing any damaged DACM components with new or serviceable 
components; and flushing/cleaning the braking system prior to replacing 
the inlet filters; in accordance with Service Bulletin MD90-32-056, 
dated October 7, 2003, and Service Bulletin MD90-32-043, Revision 01, 
dated November 9, 2000; except as discussed under ``Differences Between 
Service Information and the Proposed AD.''

Differences Between Service Information and the Proposed AD

    Although Service Bulletin MD90-32-056 recommends that ``operators 
do this service bulletin at a scheduled maintenance period when 
manpower, materials, and facilities are available,'' we have determined 
that this imprecise compliance time would not address the identified 
unsafe condition in a timely manner. In developing an appropriate 
compliance time for this proposed AD, we considered not only the 
manufacturer's recommendation, but also the degree of urgency 
associated with addressing the subject unsafe condition, the average 
utilization of the affected fleet, and the time necessary to perform 
the modifications. In light of all of these factors, we find a 
compliance time of 18 months for completing the required actions to be 
warranted, in that it represents an appropriate interval of time for 
affected airplanes to continue to operate without compromising safety.
    Although Service Bulletin MD90-32-043, Revision 01, specifies 
inspecting the DACM assembly inlet filters for damage, this proposed AD 
would require a detailed inspection of the filters to eliminate any 
possible confusion about the proper type of inspection. Note 3 of this 
proposed AD includes a definition of this type of inspection.

Costs of Compliance

    This proposed AD would affect about 115 airplanes worldwide and 24 
airplanes of U.S. registry. The proposed actions would take about 8 
work hours per airplane, at an average labor rate of $65 per work hour. 
Required parts would cost between $8,000 and $240,780 per airplane. 
Based on these figures, the estimated cost of the proposed AD for U.S. 
operators is between $204,480 and $5,791,200, or between $8,520 and 
$241,300 per airplane.

Regulatory Authority and Findings

    This rulemaking is promulgated under the authority described in 
subtitle VII, part A, subpart III, section 44701, General requirements. 
Under that section, the FAA is charged with prescribing regulations for 
practices, methods, and procedures the Administrator finds necessary 
for safety and air commerce. This regulation is within the scope of 
that authority because it addresses an unsafe condition that is likely 
to exist or develop on products identified in this AD.
    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2004-19867; Directorate Identifier 
2004-NM-58-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by January 31, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all McDonnell Douglas Model MD-90-30 
airplanes, certificated in any category.

Unsafe Condition

    (d) This AD was prompted by reports of multiple incidents of 
blown tires on landing while using maximum autobrake. We are issuing 
this AD to prevent metallic fibers from the first stage filter of 
the servo valves inside the dual anti-skid control manifolds (DACM) 
from becoming lodged in the first stage nozzle of the servo valve, 
which could lead to tire failure during high speed/high energy 
braking and possible subsequent runway departure.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Replacement of DACMs

    (f) Within 18 months after the effective date of this AD, 
replace existing DACMs with new, improved or reworked and 
reidentified DACMs, part number 6006079-2, by doing all actions in 
accordance with the Accomplishment Instructions of McDonnell Douglas 
Service Bulletin MD90-32-056, dated October 7, 2003.

    Note 1: McDonnell Douglas Service Bulletin MD90-32-056 refers to 
Aircraft Braking Systems Corporation (ABSC) Service Bulletin MD-90 
6006079-32-02, dated August 7, 2003, as an additional source of 
service information for installing new, improved or reworked and 
reidentified DACMs.

Concurrent Service Bulletin

    (g) Prior to or concurrent with the accomplishment of paragraph 
(f) of this AD, perform paragraphs (g)(1) and (g)(2) of this AD in 
accordance with the Accomplishment Instructions of McDonnell Douglas 
Service Bulletin MD90-32-043, Revision 01, dated November 9, 2000.
    (1) Perform a detailed inspection of the metered pressure inlet 
filters and other components of the DACM for damage. Replace any 
damaged DACM components with new or serviceable components, and 
flush/clean the braking system, as applicable.
    (2) Replace the metered pressure inlet filters of the DACM 
assembly with new filters.

    Note 2: McDonnell Douglas Service Bulletin MD90-32-043, Revision 
01, refers to ABSC Service Bulletin MD90-32-12, dated January 12, 
2000, as an additional source of service information for inspecting 
the components of the DACM assembly for uncleanliness, structural 
damage or excessive wear that may render the DACM inoperable, and 
for replacing those components with new or serviceable components, 
if necessary.


    Note 3: For the purposes of this AD, a detailed inspection is 
``an intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good

[[Page 75280]]

lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc. may be necessary. Surface cleaning 
and elaborate procedures may be required.''

Prior Inspection/Replacement of Inlet Filters

    (h) Inspecting and replacing DACM inlet filters and flushing/
cleaning braking systems before the effective date of this AD in 
accordance with McDonnell Douglas Service Bulletin MD90-32-043, 
dated April 10, 2000, is considered acceptable for compliance with 
the corresponding actions specified in this AD.

Alternative Methods of Compliance (AMOCs)

    (i) The Manager, Los Angeles Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19.

    Issued in Renton, Washington, on December 6, 2004.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-27512 Filed 12-15-04; 8:45 am]
BILLING CODE 4910-13-U