[Federal Register Volume 70, Number 9 (Thursday, January 13, 2005)]
[Rules and Regulations]
[Pages 2339-2342]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-538]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20010; Directorate Identifier 2003-NM-224-AD; 
Amendment 39-13938; AD 2005-01-13]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767-300 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Boeing Model 767-300 series airplanes. This AD requires 
repetitive functional tests and repetitive replacements of the 
auxiliary power unit (APU) and engine fire shutoff switches. This 
proposal also provides an optional terminating action for the 
repetitive functional tests and replacements. This AD is prompted by a 
report of the failure of the engine fire shutoff switch in the engine 
fire control module. We are issuing this AD to prevent mineral build-up 
on the APU and engine fire shutoff switches, which could lead to the 
switches failing to discharge fire suppressant to the affected fire 
zone and result in an uncontrolled engine or APU fire and consequent 
loss of the airplane.

DATES: Effective January 28, 2005. The incorporation by reference of a 
certain publication listed in the AD is approved

[[Page 2340]]

by the Director of the Federal Register as of January 28, 2005.
    We must receive comments on this AD by March 14, 2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this 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.
     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, 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 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-2005-20010; the directorate identifier for this 
docket is 2003-NM-224-AD.

Examining the Dockets

    You can examine the AD docket on the Internet at http://dms.dot.gov, or in person in 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 Docket Management System 
(DMS) receives them.

FOR FURTHER INFORMATION CONTACT: Bernie Gonzalez, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 917-6498; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: This AD is prompted by a report of the 
failure of the engine fire shutoff switch in the engine fire control 
module, which resulted in the inability to stow the thrust reverser on 
a certain Boeing Model 767 series airplane. On this installation the 
thrust reverser is operated by engine pneumatic bleed air, which is 
regulated by a spring-loaded-closed pressure regulating and shutoff 
valve (PRSOV). The PRSOV requires electrical power to stay open against 
the spring force. Its power supply is routed through the engine fire 
shutoff switch. The electrical contacts for the thrust reverser inside 
the engine fire shutoff switch are normally in the closed position. 
When the engine fire shutoff switch is pulled, during a fire or test, 
the power supplied to the thrust reverser PRSOV is removed and the 
valve closes off the engine bleed air, leaving the thrust reverser in 
the last commanded position. Investigation of the reported incident 
revealed that certain flight deck humidifiers distribute unfiltered air 
containing minerals from the potable water supply. The humidified air 
contaminates the auxiliary power unit (APU) and engine fire shutoff 
switches and may result in mineral build-up on switch contacts. The 
contamination within the fire shutoff switch gradually builds up, 
causing an increase in contact resistance. In the case of the thrust 
reverser, this contact resistance was high enough that the power 
supplied to the PRSOV was insufficient to hold the valve open. The 
PRSOV closed, leaving the thrust reverser in the deployed state. This 
same contamination can build up on the fire extinguishing switch 
contacts inside the APU and engine fire switches. Mineral build-up on 
the APU and engine fire shutoff switches, if not corrected, could lead 
to the switches failing to discharge fire suppressant to the affected 
fire zone and result in an uncontrolled engine or APU fire and 
consequent loss of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 767-26A0127, dated 
July 17, 2003. The service bulletin describes the following procedures:
    1. Doing repetitive functional tests of the APU and engine fire 
shutoff switches;
    2. Doing repetitive replacements of the APU and engine fire shutoff 
switches with new or serviceable switches; and
    3. Deactivating the Lucas (also known as TRW Systemes 
Aeronautiques) flight deck humidifier, part numbers (P/N) M01AA0101, 
M01AB0101, M01AB0102, or M01AB0103, which eliminates the need for the 
repetitive functional tests and replacements.
    We have determined that accomplishment of the actions specified in 
the service information will adequately address the unsafe condition.

FAA's Determination and Requirements of This AD

    The unsafe condition described previously is likely to exist or 
develop on other airplanes of the same type design that may be 
registered in the U.S. at some time in the future. Therefore, this AD 
is being issued to prevent mineral build-up on APU and engine fire 
shutoff switches, which could lead to the switches failing to discharge 
fire suppressant to the affected fire zone and result in an 
uncontrolled engine fire and consequent loss of the airplane. This AD 
requires repetitive functional tests and repetitive replacements of the 
APU and engine fire shutoff switches. This proposal also provides an 
optional terminating action for the repetitive functional tests and 
replacements. You must do these actions in accordance with the service 
information described previously, except as discussed under 
``Differences Between the AD and the Service Bulletin.''

Differences Between the AD and the Service Bulletin

    Operators should note that the service bulletin specifies the 
initial compliance time as ``after the airplane has 12 calendar months 
of service but within 18 calendar months since airplane delivery. * * 
*'' This AD, however, specifies the initial compliance time as within 
18 months since the date of issuance of the original Airworthiness 
Certificate or the original Export Certificate of Airworthiness. This 
decision is based on our determination that ``since airplane delivery'' 
may be interpreted differently by different operators. We find that 
this terminology is generally understood within the industry and 
records will always exist that establish these dates with certainty. 
This AD also omits reference to ``after the airplane has 12 calendar 
months of service,'' since accomplishing the initial actions within 18 
months of service provides an acceptable level of safety. Thus the 
compliance time specified in this AD includes any airplanes that may 
have been operating since delivery.
    Operators should also note that the service bulletin states, 
``Operators who perform the 90 calendar day inspection and the 18 
calendar month switch servicing can avoid the required test interval 
shown in Figure 1, by deactivation of the Lucas (also known as TRW 
Systemes Aeronautiques) Flight Deck Humidifier.'' This AD, however, 
specifies that if an operator deactivates the flight deck humidifier, 
all APU and engine fire shutoff switches must be

[[Page 2341]]

replaced with new or serviceable switches before further flight. We 
have determined that if a flight deck humidifier is deactivated shortly 
before any required replacement or required functional test, it might 
be possible for any switch to have a latent type of failure due to the 
previous exposure to moisture and minerals from the humidifier. To 
address this unsafe condition, we have added a requirement to paragraph 
(j) of this AD to replace all switches after deactivating the flight 
deck humidifier. We have also added requirements to paragraph (k) of 
this AD to ensure an operator performs the repetitive functional tests 
and replacements of switches after reactivating the flight deck 
humidifier.

Costs of Compliance

    None of the airplanes affected by this action are on the U.S. 
Register. All airplanes affected by this AD are currently operated by 
non-U.S. operators under foreign registry; therefore, they are not 
directly affected by this AD action. However, we consider this AD 
necessary to ensure that the unsafe condition is addressed if any 
affected airplane is imported and placed on the U.S. Register in the 
future.
    If an affected airplane is imported and placed on the U.S. Register 
in the future, the required functional test would take about 2 work 
hours per switch, at an average labor rate of $65 per work hour. We 
estimate there are 3 switches per airplane. No parts would be required. 
Based on these figures, the estimated cost of the AD would be $390 per 
airplane, per testing cycle.
    If an affected airplane is imported and placed on the U.S. Register 
in the future, the required switch replacement would take about 2 work 
hours per switch, at an average labor rate of $65 per work hour. 
Required parts would cost about $1,000 per switch, if replaced with a 
serviceable switch. Based on these figures, the estimated cost of the 
AD would be $1,130 per switch, per replacement.

FAA's Determination of the Effective Date

    No airplane affected by this AD is currently on the U.S. Register. 
Therefore, providing notice and opportunity for public comment is 
unnecessary before this AD is issued, and this AD may be made effective 
in less than 30 days after it is published in the Federal Register.

Comments Invited

    Although this is a final rule that was not preceded by notice and 
an opportunity for public comment, we invite you to submit any written 
relevant data, views, or arguments regarding this AD. Send your 
comments to an address listed under ADDRESSES. Include ``Docket No. 
FAA-2005-20010; Directorate Identifier 2003-NM-224-AD'' at the 
beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of the 
AD. We will consider all comments received by the closing date and may 
amend the 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 AD. Using the search function of our docket 
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 the 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.

Authority for This Rulemaking

    The FAA's authority to issue rules regarding aviation safety is 
found in Title 49 of the United States Code. Subtitle I, section 106 
describes the authority of the FAA Administrator. Subtitle VII, 
Aviation Programs, describes in more detail the scope of the agency's 
authority.
    This rulemaking is promulgated under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in 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.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will 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 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 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new AD:

2005-01-13 Boeing: Amendment 39-13938. Docket No. FAA-2005-20010; 
Directorate Identifier 2003-NM-224-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective January 
28, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 767-300 series airplanes, 
certificated in any category; as listed in Boeing Alert Service 
Bulletin 767-26A0127, dated July 17, 2003.

Unsafe Condition

    (d) This AD was prompted by a report of the failure of the 
engine fire shutoff switch in the engine fire control module. The 
Federal Aviation Administration is issuing this AD to prevent 
mineral build-up on the auxiliary power unit (APU) and engine fire 
shutoff switches, which could lead to the switches failing to 
discharge fire suppressant to the affected fire zone and result in 
an uncontrolled engine or APU fire and consequent loss of the 
airplane.

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.

[[Page 2342]]

Service Bulletin Reference

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Boeing Alert Service Bulletin 767-
26A0127, dated July 17, 2003.

Initial and Repetitive Functional Tests

    (g) At the later of the compliance times specified in paragraphs 
(g)(1) and (g)(2) of this AD, do a functional test of the APU and 
engine fire shutoff switches, in accordance with the service 
bulletin. Repeat the functional test thereafter at intervals not to 
exceed 18 months.
    (1) Within 18 months since the date of issuance of the original 
Airworthiness Certificate or the original Export Certificate of 
Airworthiness.
    (2) Within 90 days after the effective date of this AD.

Corrective Action for Failure of a Fire Shutoff Switch

    (h) If any APU or engine fire shutoff switch fails during any 
functional test required by paragraph (g) or (k) of this AD, before 
further flight, replace the switch with a new or serviceable switch, 
in accordance with the service bulletin. Repeat the switch 
replacement thereafter at intervals not to exceed 36 months.

Initial and Repetitive Replacements of Fire Shutoff Switches

    (i) Within 18 months after the effective date of this AD, 
replace all APU and engine fire shutoff switches that have not been 
previously replaced in accordance with paragraph (h) of this AD with 
new or serviceable switches, in accordance with the service 
bulletin. Repeat the switch replacement thereafter at intervals not 
to exceed 36 months.

Optional Terminating Action: Deactivation of Humidifier

    (j) Accomplishment of the actions specified in paragraphs (j)(1) 
and (j)(2) of this AD, terminates the repetitive requirements of 
paragraphs (g), (h), and (i) of this AD, except as provided by 
paragraph (k) of this AD.
    (1) Deactivate the Lucas humidifier, part number (P/N) 
M01AA0101, M01AB0101, M01AB0102, or M01AB0103, in accordance with 
the service bulletin.
    (2) Before further flight following the deactivation specified 
in paragraph (j)(1) of this AD, replace all APU and engine fire 
shutoff switches with new or serviceable switches, in accordance 
with the service bulletin.

Reactivation of Lucas Humidifier

    (k) For any airplane on which Lucas humidifier, P/N M01AA0101, 
M01AB0101, M01AB0102, or M01AB0103, is reactivated after the 
effective date of this AD: Do the actions required by paragraphs 
(k)(1) and (k)(2) of this AD at the specified compliance times.
    (1) Within 18 months after reactivating the humidifier, and 
thereafter at intervals not to exceed 18 months, do the functional 
tests required by paragraph (g) of this AD.
    (2) Within 36 months after reactivating the humidifier, and 
thereafter at intervals not to exceed 36 months, replace all APU and 
engine fire shutoff switches that have not been previously replaced 
in accordance with paragraph (h) of this AD. Do the replacements in 
accordance with paragraph (i) of this AD.

Alternative Methods of Compliance (AMOC)

    (l) 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.

Material Incorporated by Reference

    (m) You must use Boeing Alert Service Bulletin 767-26A0127, 
dated July 17, 2003, to perform the actions that are required by 
this AD, unless the AD specifies otherwise. The Director of the 
Federal Register approved the incorporation by reference of this 
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You 
can get copies of the document from Boeing Commercial Airplanes, 
P.O. Box 3707, Seattle, Washington 98124-2207. You can review copies 
at the Docket Management Facility office, U.S. Department of 
Transportation, 400 Seventh Street SW, room PL-401, Nassif Building, 
Washington, DC; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on December 29, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-538 Filed 1-12-05; 8:45 am]
BILLING CODE 4910-13-P