[Federal Register Volume 65, Number 91 (Wednesday, May 10, 2000)]
[Proposed Rules]
[Pages 30031-30033]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-11720]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-368-AD]
RIN 2120-AA64


Airworthiness Directives; Raytheon (Beech) Model MU-300, MU-300-
10, 400, and 400A 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 all Raytheon (Beech) Model MU-300, 
MU-300-10, 400, and 400A series airplanes. This proposal would require 
repetitive inspections of the bleed air supply tube assemblies for 
discrepancies; and replacement of the bleed air tube assembly with a 
new bleed air tube assembly, if necessary. In lieu of accomplishing the 
repetitive inspections, this proposal also would provide for a revision 
of the Airworthiness Limitations to incorporate, among other things, 
certain inspections and compliance times to detect discrepancies of the 
subject area; and corrective action, if necessary. This proposal is 
prompted by reports of broken wire braiding in the bellows assembly of 
the bleed air supply tube assembly due to premature failure from 
loading. The actions specified by the proposed AD are intended to 
prevent the bleed air supply tube assembly from disconnecting and 
contacting other pneumatic or electrical systems of the airplane or 
expelling high temperature air on surrounding systems and structure. 
Such a condition could reduce the functional capabilities of the 
airplane or the ability of the flight crew to cope with adverse 
operating conditions.

DATES: Comments must be received by June 26, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-368-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.
    The service information referenced in the proposed rule may be 
obtained from Raytheon Aircraft Company, Manager Service Engineering, 
Beechjet Premier Technical Support, P.O. Box 85, Wichita, Kansas 67201-
0085. 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.

[[Page 30032]]


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 98-NM-368-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. 98-NM-368-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports of broken wire braiding in the bellows 
assembly of the bleed air supply tube assembly on Raytheon (Beech) 
Model MU-300, MU-300-10, 400, and 400A series airplanes. Investigation 
revealed that the stainless steel wire mesh braiding that restrains the 
bellows is subject to loading, which causes the braiding to fail 
prematurely. Failure of the wire braiding, if not corrected, could 
cause the bleed air supply tube assembly to disconnect and contact 
other pneumatic or electrical systems of the airplane or expel high 
temperature air on surrounding systems and structure. Such a condition 
could reduce the functional capabilities of the airplane or the ability 
of the flight crew to cope with adverse operating conditions.

New Revisions to Airworthiness Limitations Section

    The FAA has reviewed and approved Chapter 4, ``Airworthiness 
Limitations'' of Raytheon Aircraft Beechjet 400/400A Maintenance Manual 
(for Model MU-300-10, 400, and 400A series airplanes), Revision B23, 
dated December 18, 1998, and Section MR-11-00, ``Airworthiness 
Limitations'' of Raytheon Aircraft Diamond 1/1A MU-300 Maintenance 
Requirement Manual (for Model MU-300 series airplanes), Revision 8, 
dated December 18, 1998. These revisions describe, among other things, 
specific inspection and compliance times to detect broken wire braids, 
leakage, or rupture of the bellows assembly in the bleed air supply 
tube assembly; and corrective action, if necessary. The corrective 
action involves replacement of the bleed air tube assembly with a new 
bleed air tube assembly. Accomplishment of the procedures specified in 
the Airworthiness Limitations Section (ALS) or the repetitive 
inspections described below 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 repetitive general visual inspections of the 
bleed air supply tube assemblies for broken wire braiding on the 
bellows assemblies or for ruptured or leaking bellow assemblies; and 
replacement of the bleed air tube assembly with a new bleed air tube 
assembly, if necessary. In lieu of accomplishing the repetitive 
inspections, the proposed AD also would provide for a revision of the 
ALS of Raytheon Aircraft Beechjet 400/400A Maintenance Manual (for 
Model MU-300-10, 400, and 400A series airplanes), and Raytheon Aircraft 
Diamond 1/1A MU-300 Maintenance Manual (for Model MU-300 series 
airplanes) to incorporate Revision B23, dated December 18, 1998 (for 
Model MU-300-10, 400, and 400A series airplanes), and Revision 8, dated 
December 18, 1998 (for Model MU-300 series airplanes); as applicable.

Cost Impact

    There are approximately 530 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 452 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
1 work hour per airplane to accomplish the proposed inspection, and 
that the average labor rate is $60 per work hour. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $27,120, or $60 per airplane, per inspection cycle.
    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.
    Should an operator elect to accomplish the optional terminating 
action that would be provided by this AD action, it would take 
approximately 1 work hour to accomplish it, at an average labor rate of 
$60 per work hour. Based on these figures, the cost impact of the 
optional terminating action would be $60 per airplane.

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:

[[Page 30033]]

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 (Formerly Beech): Docket 98-NM-368-AD.

    Applicability: All Model MU-300, MU-300-10, 400, and 400A series 
airplanes, 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) 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 bleed air supply tube assembly from disconnecting 
and contacting other pneumatic or electrical systems of the airplane 
or expelling high temperature air on surrounding systems and 
structure, which could result in reduced functional capabilities of 
the airplane or the ability of the flight crew to cope with adverse 
operating conditions; accomplish the following:

Inspection

    (a) Within 200 hours time-in-service after the effective date of 
this AD, except as provided by paragraph (b) of this AD, perform a 
general visual inspection of the bleed air supply tube assemblies 
for broken wire braiding on the bellows assemblies or for ruptured 
or leaking bellow assemblies. The bleed air supply tube assemblies 
are located within the aft fuselage and connect to mating ducting in 
the pylon area on the right and left side of the airplane. Repeat 
the inspection thereafter at intervals not to exceed 400 hours time-
in-service. If any broken wire is detected or if any bellow assembly 
is ruptured or leaking, prior to further flight, replace the bleed 
air tube assembly with a new bleed air tube assembly.

    Note 2: For the purposes of this AD, a general visual inspection 
is defined as ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

Optional Implementation of Airworthiness Limitations Section

    (b) Instead of accomplishing the requirements of paragraph (a) 
of this AD, revise the Airworthiness Limitations Sections of the 
Instructions for Continued Airworthiness by incorporating the 
procedures specified in Chapter 4, ``Airworthiness Limitations'' of 
Raytheon Aircraft Beechjet 400/400A Maintenance Manual, Revision 
B23, dated December 18, 1998 (for Model MU-300-10, 400, and 400A 
series airplanes); or Section MR-11-00, ``Airworthiness 
Limitations'' of Raytheon Aircraft Diamond 1/1A MU-300 Maintenance 
Requirement Manual, Revision 8, dated December 18, 1998 (for Model 
MU-300 series airplanes); as applicable.
    (c) Except as provided in paragraph (d) of this AD: After the 
action specified in paragraph (b) of this AD has been accomplished, 
no alternative inspections or inspection intervals may be approved 
for the part specified in paragraph (b) of this AD.

Alternative Methods of Compliance

    (d) 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

    (e) Special flight permits may be issued in accordance with 
Sec. 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 3, 2000.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-11720 Filed 5-9-00; 8:45 am]
BILLING CODE 4910-13-U