[Federal Register Volume 69, Number 172 (Tuesday, September 7, 2004)]
[Proposed Rules]
[Pages 54060-54063]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-20210]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18999; Directorate Identifier 2003-NM-259-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400, -400D, and -400F 
Series 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 certain Boeing Model 747-400, -400D, and -400F series airplanes. 
This proposed AD would require replacing at least one flap control unit 
(FCU) in the main equipment center with a new or modified FCU. This 
proposed AD is prompted by a report indicating that, after takeoff, an 
airplane was required to return to the airport because the autopilot 
disengaged. The report also indicated that, upon selecting flaps for 
landing, the flaps indication display did not indicate the flap 
setting, requiring the airplane to land in alternate flap mode. We are 
proposing this AD to prevent disconnection of autoland/autopilot 
functions and loss of primary flaps control and flaps indication 
display due to disengagement of all three FCUs at the same time, which 
could lead to a non-normal high speed landing with the flaps retracted, 
increased pilot workload, and possible runway departure at high speeds 
during landing.

DATES: We must receive comments on this proposed AD by October 22, 
2004.

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.

[[Page 54061]]

    For the service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207.
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or 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.

FOR FURTHER INFORMATION CONTACT:
    Technical Information: Douglas Tsuji, Aerospace Engineer, Systems 
and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 917-6487; fax (425) 917-6590.
    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-2004-18999; 
Directorate Identifier 2003-NM-259-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 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 a report indicating that, after takeoff, a Boeing 
Model 747-400 series airplane was required to return to the airport 
because the autopilot disengaged. The report also indicated that, upon 
selecting flaps for landing, the flaps indication display did not 
indicate the flap setting, requiring the airplane to land in alternate 
flap mode. The root cause of these conditions has been determined to be 
the susceptibility of the flap control units (FCUs) to certain external 
failures of the position switch circuit of the leading edge flap. These 
external failures can cause all three FCUs to disengage at the same 
time, which could result in disconnection of autoland/autopilot 
functions and loss of primary flaps control and flaps indication 
display. These conditions, if not corrected, could lead to a non-normal 
high speed landing with the flaps retracted, increased pilot workload, 
and possible runway departure at high speeds during landing.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 747-27A2386, dated 
March 13, 2003, which describes procedures for replacing FCUs having 
part number (P/N) 285U0011-207, located in the main equipment center, 
with new or modified FCUs having P/N 285U0011-208. The service bulletin 
specifies that at least one FCU per airplane must be replaced to 
prevent the malfunction of the primary flaps control and flaps 
indication display.
    Boeing Alert Service Bulletin 747-27A2386 refers to Boeing 
Component Service Bulletin 285U0011-27-06, dated March 13, 2003, as an 
additional source of service information for modifying an FCU having P/
N 285U0011-207 to P/N 285U0011-208.
    Boeing Alert Service Bulletin 747-27A2386 also specifies prior or 
concurrent accomplishment of Boeing Service Bulletin 747-27-2319, dated 
January 24, 1991, which describes procedures for replacing FCUs having 
P/N 285U0011-205 or 285U0011-206, located in the main equipment center, 
with new or modified FCUs having P/N 285U0011-207.
    Boeing Service Bulletin 747-27-2319 refers to Boeing Component 
Service Bulletin 285U0011-27-04, dated January 24, 1991, as an 
additional source of service information for modifying an FCU having P/
N 285U0011-205 or 285U0011-206 to P/N 285U0011-207.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.

Clarification of FCU Replacement Specified in Boeing Alert Service 
Bulletin

    Although the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-27A2386 specify to ``replace the FCUs as shown in Figure 
1'' (which illustrates replacement of three FCUs), only a minimum of 
one FCU for each airplane must be replaced as specified in paragraph 
1.E., ``Compliance,'' of the service bulletin. In paragraph 1.D., 
``Description,'' the service bulletin specifies that ``a minimum of one 
FCU for each airplane must be replaced to prevent the malfunction of 
the primary flaps control and flaps indication display.'' Replacing a 
minimum of one FCU having P/N 285U0011-207 with P/N 285U0011-208 
addresses the unsafe condition specified in the proposed AD.

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 at least one FCU having P/N 285U0011-207, 
located in the main equipment center, with an FCU having P/N 285U0011-
208. For certain

[[Page 54062]]

airplanes, the proposed AD would first require replacing the three FCUs 
having P/N 285U0011-205 or 285U0011-206 with FCUs having P/N 285U0011-
207. The proposed AD would require you to use Boeing Alert Service 
Bulletin 747-27A2386, dated March 13, 2003; and Boeing Service Bulletin 
747-27-2319, dated January 24, 1991; described previously to perform 
these actions.

Costs of Compliance

    This proposed AD would affect about 614 airplanes worldwide and 87 
airplanes of U.S. registry. The following table provides the estimated 
costs for U.S. operators to comply with this proposed AD.

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                                                                             Average
                         Replacement                           Work hours   labor rate     Parts       Cost per
                                                                             per hour                  airplane
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                                                 Estimated Costs
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With new -208 FCU...........................................            2          $65      $78,550      $78,680
With modified -208 FCU......................................           10           65          975        1,625
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                                   Estimated Concurrent Service Bulletin Costs
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With new -207 FCU...........................................            3           65      235,650      235,845
With modified -207 FCU......................................           87           65        2,925        8,580
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Regulatory Findings

    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):

Boeing: Docket No. FAA-2004-18999; Directorate Identifier 2003-NM-
259-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive comments 
on this AD action by October 22, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Model 747-400, -400D, and -400F series 
airplanes, as listed in Boeing Alert Service Bulletin 747-27A2386, 
dated March 13, 2003; certificated in any category.

Unsafe Condition

    (d) This AD was prompted by a report indicating that, after 
takeoff, an airplane was required to return to the airport because the 
autopilot disengaged. The report also indicated that, upon selecting 
flaps for landing, the flaps indication display did not indicate the 
flap setting, requiring the airplane to land in alternate flap mode. We 
are issuing this AD to prevent disconnection of autoland/autopilot 
functions and loss of primary flaps control and flaps indication 
display due to disengagement of all three flap control units (FCUs) at 
the same time, which could lead to a non-normal high speed landing with 
the flaps retracted, increased pilot workload, and possible runway 
departure at high speeds during landing.

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.

Replace FCU

    (f) At the earliest of the times specified in paragraphs (f)(1), 
(f)(2), and (f)(3) of this AD: Replace at least one FCU having P/N 
285U0011-207 with a new or modified FCU having P/N 285U0011-208 in 
accordance with the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-27A2386, dated March 13, 2003.
    (1) Within 60 months after the effective date of this AD.
    (2) Within 25,000 flight hours after the effective date of this AD.
    (3) Within 4,000 flight cycles after the effective date of this AD.

    Note 1: Boeing Alert Service Bulletin 747-27A2386, dated March 
13, 2003, refers to Boeing Component Service Bulletin 285U0011-27-
06, dated March 13, 2003, as an additional source of service 
information for modifying an FCU having P/N 285U0011-207 to P/N 
285U0011-208.


Actions Required Before or Concurrently With Paragraph (f)

    (g) For airplanes listed in Boeing Service Bulletin 747-27-2319, 
dated January 24, 1991: Before or concurrent with the accomplishment 
of paragraph (f) of this AD, replace the three FCUs having P/N 
285U0011-205 or 285U0011-206 with new or modified FCUs having P/N 
285U0011-207 in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 747-27-2319, dated January 24, 1991.

    Note 2: Boeing Service Bulletin 747-27-2319, dated January 24, 
1991, refers to Boeing Component Service Bulletin 285U0011-27-04, 
dated January 24, 1991, as an additional source of service 
information for modifying

[[Page 54063]]

the FCUs having P/N 285U0011-205 or 285U0011-206 to P/N 285U0011-
207.

Parts Installation

    (h) As of the effective date of this AD, no person may install 
on any airplane an FCU having P/N 285U0011-205 or -206.

Alternative Methods of Compliance (AMOCs)

    (i) The Manager, Seattle 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 August 25, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-20210 Filed 9-3-04; 8:45 am]
BILLING CODE 4910-13-P