[Federal Register Volume 65, Number 157 (Monday, August 14, 2000)]
[Proposed Rules]
[Pages 49523-49524]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-20507]



[[Page 49523]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-212-AD]
RIN 2120-AA64


Airworthiness Directives; Raytheon Model BAe.125, Hawker 800 (U-
125A), and Hawker 800XP 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 Model BAe.125, Hawker 800 
(U-125A), and Hawker 800XP series airplanes. This proposal would 
require removal of existing clamps, bedding tapes, and rubber 
connecting sleeves at the ends of the turbine air discharge duct and 
the water separator, and replacement of the clamps and rubber 
connecting sleeves with new, improved components. This action is 
intended to prevent the turbine air discharge duct or water separator 
outlet duct from disconnecting from the cold air unit turbine or from 
the water separator, resulting in the loss of air supply to maintain 
adequate cabin pressure. Loss of adequate cabin pressure at high 
altitude would require emergency procedures, such as use of oxygen, 
auxiliary pressurization, or emergency descent.

DATES: Comments must be received by September 28, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-212-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. 2000-NM-212-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 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Raytheon Aircraft Company, 9709 East Central, Wichita, 
Kansas 67206. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at 
the FAA, Small Airplane Directorate, Wichita Aircraft Certification 
Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, 
Kansas.

FOR FURTHER INFORMATION CONTACT: Paul C. DeVore, Aerospace Engineer, 
Systems and Propulsion Branch, ACE-116W, FAA, Small Airplane 
Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, 
Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 
946-4142; fax (316) 946-4407.

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.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-212-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. 2000-NM-212-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that in four instances the 
turbine air discharge duct became disconnected from the cold air unit 
and/or from the water separator in flight, resulting in cabin 
depressurization. The disconnection apparently occurred, because the 
design of the sleeve connection, with bedding tape installed under the 
clamps, is prone to slippage. This condition, if not corrected, may 
lead to the loss of air supply to maintain adequate cabin pressure. 
Such a loss of cabin pressure at high altitude would require emergency 
procedures, such as use of oxygen, auxiliary pressurization, or 
emergency descent.
    If cabin depressurization occurs on long overwater flights, 
descending to a lower altitude may not allow sufficient range to reach 
a suitable airfield. Descending to a lower altitude would result in 
higher fuel consumption and, therefore, less range. If the fuel 
consumption and reserves had been calculated based on a fuel burn rate 
at a high cruise altitude, and a loss of pressure forced the crew to 
alter their plan, then the available fuel may no longer allow them to 
reach their destination or to reach it with sufficient reserves.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Raytheon Service Bulletin SB 21-
3377, Revision 1, dated July 2000, which describes procedures for 
removing the clamps, bedding strips, and rubber connecting sleeves on 
both ends of the turbine air discharge duct and the water separator and 
replacing the clamps and connecting sleeves with new, improved 
components. 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 require accomplishment of the actions specified in 
the service bulletin described previously.

[[Page 49524]]

Cost Impact

    There are approximately 220 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 154 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
8 work hours per airplane to accomplish the proposed installation, and 
that the average labor rate is $60 per work hour. Required parts would 
cost approximately $492 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be 
$149,688, or $972 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 proposed 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:

Raytheon Aircraft Company: Docket 2000-NM-212-AD.

    Applicability: Model BAe.125 Series 800A (C-29A and U-125) 
series airplanes, Hawker 800 (U-125A) series airplanes up to and 
including serial number 258406, and Hawker 800XP series airplanes up 
to and including serial number 258459; 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 (b) 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 prevent the turbine air discharge duct or water separator 
outlet duct from disconnecting from the cold air unit turbine or 
from the water separator, resulting in the loss of air supply to 
maintain adequate cabin pressure, accomplish the following:

Replacement

    (a) Remove the clamps, bedding tapes, and rubber connecting 
sleeves at the ends of the air turbine discharge duct and the water 
separator, and replace the clamps and rubber connecting sleeves with 
new, improved components, in accordance with the Accomplishment 
Instructions of Raytheon Service Bulletin SB 21-3377, Revision 1, 
dated July 2000, at the earliest of the times specified in 
paragraphs (a)(1), (a)(2), and (a)(3) of this AD.
    (1) Prior to any extended over-water operation.
    (2) Within the next 300 hours time-in-service after the 
effective date of this AD.
    (3) Within the next six months after the effective date of this 
AD.

    Note 2: An extended over-water operation is defined in 14 CFR 
1.1 as ``* * * an operation over water at a horizontal distance of 
more than 50 nautical miles from the nearest shoreline. * * *''

Alternative Methods of Compliance

    (b) 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, Wichita Aircraft Certification 
Office (ACO), FAA, Small 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, Wichita ACO.

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

Special Flight Permits

    (c) 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 August 8, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate Aircraft Certification 
Service.
[FR Doc. 00-20507 Filed 8-11-00; 8:45 am]
BILLING CODE 4910-13-P