

[Federal Register: August 16, 2007 (Volume 72, Number 158)]
[Proposed Rules]               
[Page 45980-45982]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16au07-30]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28943; Directorate Identifier 2007-NM-011-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 767-300F Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (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 767-300F series airplanes. This proposed AD 
would require replacing the rotomolded duct(s) of the mix manifold 
system with new duct(s). This proposed AD results from a report of 
failures of the duct joint seal of the mix manifold system. We are 
proposing this AD to prevent air conditioning leakage into the mix 
manifold bay. Such leakage could decrease the air flow to the flight 
compartment and main cabin or could allow smoke into the flight 
compartment in the event of a fire in the main cabin or forward cargo 
compartment.

DATES: We must receive comments on this proposed AD by October 1, 2007.

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

[[Page 45981]]

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room W12-140 on the ground floor of the 
West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for the service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Jeffrey S. Palmer, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 917-6481; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2007-
28943; Directorate Identifier 2007-NM-011-AD'' at the beginning 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 received 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.


Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Operations office between 9 

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The 
Docket Operations office (telephone (800) 647-5527) is located on the 
ground level of the West 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 receives them.

Discussion

    We have received a report of more than ten failures of the duct 
joint seal of the mix manifold system on Boeing Model 767-300F series 
airplanes. The seal failures resulted in air conditioning leakage into 
the mix manifold bay, which consequently decreased the air flow to the 
flight compartment and main cabin. The failed ducts were made from 
rotomolded nylon and were between 7 and 9 inches in diameter. Service 
history has shown that the ducts made from rotomolded nylon material 
that are larger than 6.5 inches in diameter can fail as a result of 
joint seal failures, loose clamps, and duct deformation due to 
insufficient rigidity. This condition, if not corrected, could result 
in air conditioning leakage into the mix manifold bay. Such leakage 
could decrease the air flow to the flight compartment and main cabin or 
could allow smoke into the flight compartment in the event of a fire in 
the main cabin or forward cargo compartment.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 767-21-
0192, dated March 23, 2006. The service information describes 
procedures for replacing the rotomolded duct(s) of the mix manifold 
system with new duct(s). Accomplishing the actions specified in the 
service information is intended to adequately address the unsafe 
condition.

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. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously.

Costs of Compliance

    There are about 40 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 32 airplanes of 
U.S. registry. The proposed actions would take about 2 or 8 work hours 
per airplane, at an average labor rate of $80 per work hour. Required 
parts would cost about $4,123 or $42,825 per airplane. Based on these 
figures, the estimated cost of the proposed AD for U.S. operators is 
$4,283 or $43,465 per airplane. (The estimated work hours and costs 
depend on the airplane configuration).

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. 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.
    We are issuing this rulemaking 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 
rulemaking action.

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 and placed it in the AD docket. See the 
ADDRESSES section

[[Page 45982]]

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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

BOEING: Docket No. FAA-2007-28943; Directorate Identifier 2007-NM-
011-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
1, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 767-300F series airplanes, 
certificated in any category; as identified in Boeing Special 
Attention Service Bulletin 767-21-0192, dated March 23, 2006.

Unsafe Condition

    (d) This AD results from a report of failures of the duct joint 
seal of the mix manifold system. We are issuing this AD to prevent 
air conditioning leakage into the mix manifold bay. Such leakage 
could decrease the air flow to the flight compartment and main cabin 
or could allow smoke into the flight compartment in the event of a 
fire in the main cabin or forward cargo compartment.

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

    (f) Within 36 months after the effective date of this AD, do the 
applicable action specified in Table 1 of this AD in accordance with 
the Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 767-21-0192, dated March 23, 2006.

                          Table 1.--Replacement
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For airplanes identified in the service
             bulletin as--                  Do the following action--
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(1) Group 1 airplanes..................  Replace the rotomolded duct
                                          between the transition duct of
                                          the right cooling pack and the
                                          mix manifold with a new duct
                                          made of aluminum.
(2) Group 2 airplanes..................  Replace the rotomolded ducts of
                                          the mix manifold system with
                                          new ducts made from
                                          Kevlar[supreg] and aluminum.
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Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

    Issued in Renton, Washington, on July 30, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-16095 Filed 8-15-07; 8:45 am]

BILLING CODE 4910-13-P
