[Federal Register Volume 65, Number 104 (Tuesday, May 30, 2000)]
[Proposed Rules]
[Pages 34420-34422]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-13450]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-260-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 777-200 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Boeing Model 777-
200 series airplanes, that currently requires a one-time inspection to 
determine the serial numbers of various switch modules on the overhead 
panel and control stand, and replacement of switch modules with new, 
improved modules. The existing AD also requires repetitive tests of the 
cargo fire extinguishing system, and one-time tests of the fuel 
crossfeed valve, pack, trim air, and alternate flap control switches; 
and repair or replacement of switch modules with new improved modules, 
if necessary.
    This action would revise the applicability of the existing AD. This 
action also would require replacement of the existing switch modules 
with new switch modules; replacement of the existing module assemblies 
with new module assemblies; or reworked module assemblies; as 
applicable. This proposal is prompted by the FAA's determination that 
certain switches are susceptible to contamination. The actions 
specified by the proposed AD are intended to minimize contamination of 
the switch contacts and consequent failure of the switches, which, if 
not corrected, could result in inability of the flight crew to activate 
the cargo fire extinguishing, fuel, air conditioning, and alternate 
flap systems.

DATES: Comments must be received by July 14, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-260-AD, 1601 Lind Avenue, SW.,

[[Page 34421]]

Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Mohamed Jamil, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98055-4056; telephone (425) 227-2677; fax (425) 
227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-260-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 97-NM-260-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On October 2, 1996, the FAA issued AD 96-20-01, amendment 39-9767 
(61 FR 53035, dated October 10, 1996), applicable to certain Boeing 
Model 777-200 series airplanes, to require a one-time inspection to 
determine the serial numbers of various switch modules on the overhead 
panel and control stand, and replacement of switch modules with new, 
improved modules. This AD also requires repetitive tests of the cargo 
fire extinguishing system, and one-time tests of the fuel crossfeed 
valve, pack, trim air, and alternate flap control switches; and repair 
or replacement of switch modules with new improved modules, if 
necessary.
    That action was prompted by a report indicating that the flight 
crew received a warning of fire in the forward cargo compartment during 
flight; later inspection revealed that the metered fire bottles failed 
to discharge possibly due to contamination in the arming switch of the 
cargo fire extinguishing system. The requirements of that AD are 
intended to minimize contamination of the switch contacts and 
consequent failure of the switches, which, if not corrected, could 
result in inability of the flight crew to activate the cargo fire 
extinguishing, fuel, air conditioning, and alternate flap systems.

Actions Since Issuance of Previous Rule

    In the preamble to AD 96-20-01, the FAA specified that the actions 
required by that AD were considered to be interim action. The FAA 
indicated that it may consider further rulemaking to address other 
switches that may be susceptible to contamination. The FAA has 
determined that further rulemaking action is indeed necessary; this 
proposed AD follows from that determination.
    Since the issuance of AD 96-20-01, the FAA has determined that 
certain switches, including the ten switches previously replaced in 
accordance with AD 96-20-01, are susceptible to the contamination as a 
result of particles originating from a component internal to the 
switches (as discussed in the preamble of AD 96-20-01). Such 
contamination could result in the failure of the switches and 
consequent inability of the flight crew to activate the cargo fire 
extinguishing, fuel, air conditioning, and alternate flap systems. In 
addition, analysis indicates that the functional tests required by AD 
96-20-01 do not provide any additional increase in safety. Therefore, 
this proposed AD would eliminate the repetitive functional tests of the 
cargo fire extinguishing system previously required by AD 96-20-01.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
777-31A0019, Revision 4, dated April 27, 2000, which describes 
procedures for replacing the switch modules in certain pushbutton 
switches in the flight compartment with new, improved switch modules. 
Operators would have the option of choosing one of the following 
methods for replacing the switch modules:
    <bullet> Method I: Replacement of the existing switch modules with 
new switch modules (including changing the part number of the reworked 
module assemblies and control stand assembly).
    <bullet> Method II: Replacement of the existing switch modules with 
new switch modules, and replacement of existing module assemblies with 
new module assemblies or reworked module assemblies (including changing 
the part number of the control stand assembly).
    Accomplishment of the actions specified in the service bulletin is 
intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 96-20-01 to require accomplishment of 
the actions specified in the service bulletin described previously. The 
proposed AD also would revise the applicability of the existing AD to 
include additional airplanes that are subject to the identified unsafe 
condition.

Explanation of Change Made to Applicability Statement

    Operators should note that the applicability of the proposal 
differs from the applicability of AD 96-20-01. The applicability has 
been revised to include additional airplanes (i.e., line positions 41 
through 85 inclusive) that are subject to the identified unsafe 
condition of this AD.
    Operators also should note that the applicability of AD 96-20-01 
identified the affected airplanes by ``line positions.'' The 
terminology ``line positions'' refers to airplane line numbers, rather 
than the manufacturer's tracking numbers for production airplanes. To 
clarify the affected airplanes, the applicability of this AD has been 
revised to identify those airplanes by ``line numbers.''

[[Page 34422]]

Cost Impact

    There are approximately 85 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 23 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
20 work hours (for Method I) or 9 work hours (for Method II) per 
airplane to accomplish the proposed replacement, at an average labor 
rate of $60 per work hour. Required parts would cost approximately 
$12,785 per airplane. Based on these figures, the cost impact of the 
proposed requirements of this AD on U.S. operators is estimated to be 
$321,655, or $13,985 per airplane (for Method I), or $306,475, or 
$13,325 per airplane (for Method II).
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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 39-9767 (61 FR 
53035, dated October 10, 1996), and by adding a new airworthiness 
directive (AD), to read as follows:

Boeing: Docket 97-NM-260-AD. Supersedes AD 96-20-01, Amendment 39-
9767.

    Applicability: Model 777-200 series airplanes, line numbers 1 
through 85 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 (d)(1) 
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 minimize contamination of the switch contacts and consequent 
failure of the switches, which, if not corrected, could result in 
inability of the flight crew to activate the cargo fire 
extinguishing, fuel, air conditioning, and alternate flap systems, 
accomplish the following:

Replacement and Reidentification

    (a) For Groups 1 and 2 airplanes identified in Boeing Alert 
Service Bulletin 777-31A0019, Revision 4, dated April 27, 2000, 
except as provided in paragraph (b) of this AD, within 12 months 
after the effective date of this AD, perform the actions in either 
paragraph (a)(1) or (a)(2) of this AD.
    (1) Replace the existing switch modules with new switch modules 
(including changing the part number of the reworked module 
assemblies and control stand assembly) in accordance with Method I 
of the Accomplishment Instructions of Boeing Alert Service Bulletin 
777-31A0019, Revision 4, dated April 27, 2000.
    (2) Replace the existing switch modules with new switch modules, 
and replace the existing module assemblies with new module 
assemblies or reworked module assemblies (including changing the 
part number of the control stand assembly), in accordance with 
Method II of the Accomplishment Instructions of Boeing Alert Service 
Bulletin 777-31A0019, Revision 4, dated April 27, 2000.

    Note 2: Replacements accomplished prior to the effective date of 
this AD in accordance with Boeing Alert Service Bulletin 777-
31A0019, Initial Release, dated October 2, 1997; Revision 1, dated 
March 12, 1998; Revision 2, dated March 25, 1999; or Revision 3, 
dated January 27, 2000; are acceptable for compliance with the 
requirements of paragraphs (a)(1) and (a)(2) of this AD.

    (b) For Group 2 airplanes identified in Boeing Alert Service 
Bulletin 777-31A0019, Revision 4, dated April 27, 2000, on which a 
guarded toggle passenger oxygen switch has been installed: 
Accomplishment of the actions specified in paragraphs (a)(1) and 
(a)(2) of this AD is not required for the passenger oxygen switch or 
window heat/emergency light module assembly.

Spares

    (c) As of the effective date of this AD, no person shall install 
on any airplane, any part listed in the ``Existing Part Number'' 
column of the table listed in paragraph II.D., ``Existing Parts 
Accountability,'' of Boeing Alert Service Bulletin 777-31A0019, 
Revision 4, dated April 27, 2000.

Alternative Methods of Compliance

    (d)(1) 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, Seattle 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, Seattle ACO.
    (2) Alternative methods of compliance approved previously in 
accordance with AD 96-20-01, amendment 39-9767, are not considered 
to be approved as alternative methods of compliance with this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (e) 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.

    Issued in Renton, Washington, on May 23, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-13450 Filed 5-26-00; 8:45 am]
BILLING CODE 4910-13-U