[Federal Register Volume 69, Number 103 (Thursday, May 27, 2004)]
[Proposed Rules]
[Pages 30244-30245]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-11961]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 69, No. 103 / Thursday, May 27, 2004 / 
Proposed Rules  

[[Page 30244]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-172-AD]
RIN 2120-AA64


Airworthiness Directives; BAE Systems (Operations) Limited Model 
BAe 146 and Avro 146-RJ Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain BAE Systems (Operations) 
Limited Model BAe 146 and Avro 146-RJ series airplanes. This proposal 
would require replacing the existing bellows inlet duct of the 
auxiliary power unit (APU) system with a new, improved rectangular 
metallic bellows inlet duct. This action is necessary to prevent air 
from the APU bay being ingested into the flight deck and passenger 
cabin resulting in poor air quality and, if the air is contaminated, 
possible incapacitation of the flightcrew and passengers. This action 
is intended to address the identified unsafe condition.

DATES: Comments must be received by June 28, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-172-AD, 1601 Lind Avenue, SW., 
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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2003-NM-172-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from British Aerospace Regional Aircraft American Support, 
13850 Mclearen Road, Herndon, Virginia 20171. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; fax (425) 227-1149.

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 action may be changed in 
light of the comments received.
    Submit comments using the following format:

     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2003-NM-172-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. 2003-NM-172-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, notified the FAA that an unsafe 
condition may exist on certain BAE Systems (Operations) Limited Model 
BAe 146 and Avro 146-RJ series airplanes. The CAA advises that the 
existing auxiliary power unit (APU) inlet duct and sealing 
configuration has been found to be unreliable in service. This 
condition, if not corrected, could result in air from the APU bay being 
ingested into the flight deck and passenger cabin resulting in poor air 
quality and, if the air is contaminated, possible incapacitation of the 
flightcrew and passengers.

Explanation of Relevant Service Information

    BAE Systems (Operations) Limited has issued Modification Service 
Bulletin SB.49-036-36019E, Revision 4, dated April 30, 2003. The 
service bulletin describes procedures for replacing the existing rubber 
bellows inlet duct and sealing configuration of the APU system, with a 
new, improved rectangular metallic bellows inlet duct, which 
incorporates an improved seal and clamp configuration. The procedures 
include instructions for degreasing and priming the mating surfaces of 
the new duct. Accomplishment of the actions specified in the service 
bulletin is intended to adequately address the identified unsafe 
condition. The CAA classified this service bulletin as mandatory and 
issued British airworthiness directive 007-04-2003 to

[[Page 30245]]

ensure the continued airworthiness of these airplanes in the United 
Kingdom.

FAA's Conclusions

    These airplane models are manufactured in the United Kingdom and 
are type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletin described previously, 
except as discussed below.

Difference Between the Service Information and Proposed AD

    The service bulletin specifies to submit certain information to the 
manufacturer. This AD does not include such a requirement.

Clarification of Compliance Time

    Operators should note that the British airworthiness directive and 
the service bulletin both specify to replace the APU bellows inlet duct 
at the next scheduled APU removal or the next ``C-check,'' whichever is 
first. Because maintenance and ``C-check'' schedules vary among 
operators, this proposed AD would require accomplishment of the 
replacement within 24 months or 4,000 flight cycles after the effective 
date of the AD, whichever is first. We find that compliance within 24 
months or 4,000 flight cycles after the effective date of this AD is 
appropriate for affected airplanes to continue to operate without 
compromising safety.

Cost Impact

    We estimate that 54 airplanes of U.S. registry would be affected by 
this proposed AD, that it would take approximately 2 work hours per 
airplane to accomplish the proposed replacement, and that the average 
labor rate is $65 per work hour. Required parts would cost 
approximately $4,500 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be 
$250,020, or $4,630 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this AD were not adopted. The cost impact figures 
discussed in AD rulemaking actions represent only the time necessary to 
perform the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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 adding the following new 
airworthiness directive:

BAE Systems (Operations) Limited (Formerly British Aerospace 
Regional Aircraft): Docket 2003-NM-172-AD.

    Applicability: Model 146 series airplanes with Modification 
HCM30027A, HCM36019A, or HCM30373A installed; and Model Avro 146-RJ 
series airplanes with Modification HCM36019A or HCM30373A installed; 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent air from the auxiliary power unit (APU) bay being 
ingested into the flight deck and passenger cabin resulting in poor 
air quality and, if the air is contaminated, possible incapacitation 
of the flightcrew and passengers, accomplish the following:

Replacement of Rubber Bellows Inlet Duct

    (a) Within 24 months or 4,000 flight cycles after the effective 
date of this AD, whichever is first: Replace the existing rubber 
bellows inlet duct and sealing configuration of the APU system, with 
a new, improved rectangular metallic bellows inlet duct, which 
incorporates an improved seal and clamp configuration, per the 
Accomplishment Instructions of BAE Systems (Operations) Limited 
Modification Service Bulletin SB.49-036-36019E, Revision 4, dated 
April 30, 2003. Although the service bulletin specifies to submit 
certain information to the manufacturer, this AD does not include 
such a requirement.

Alternative Methods of Compliance

    (b) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, Transport Airplane Directorate, FAA, is authorized 
to approve alternative methods of compliance for this AD.

    Note 1: The subject of this AD is addressed in British 
airworthiness directive 007-04-2003.


    Issued in Renton, Washington, on May 18, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-11961 Filed 5-26-04; 8:45 am]
BILLING CODE 4910-13-P