[Federal Register Volume 62, Number 29 (Wednesday, February 12, 1997)]
[Proposed Rules]
[Pages 6504-6505]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-3435]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-180-AD]
RIN 2120-AA64
Airworthiness Directives; Raytheon Model BAe 125-1000A and Model
Hawker 1000 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 Model BAe 125-1000A
and Model Hawker 1000 series airplanes. This proposal would require
various modifications to increase the size of certain existing pressure
venting areas and to add additional venting areas. This proposal is
prompted by results of a design review of the requirements for
certification of the cabin pressurization system. The actions specified
by the proposed AD are intended to prevent inadequate venting of cabin
pressure in the event of rapid decompression, which could cause failure
or deformation of certain structural members, and consequent reduced
controllability of the airplane.
DATES: Comments must be received by March 24, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-180-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 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,
Hawker Customer Support Department, 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.
FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2148; fax (206) 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 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 Number96-NM-180-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-103, Attention: Rules
Docket No. 96-NM-180-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has reviewed results of a design review of requirements for
certification of the cabin pressurization system on Raytheon Model BAe
125 and Model Hawker 1000 series airplanes. The Civil Aviation
Authority (the airworthiness authority for the United Kingdom) and the
manufacturer (Raytheon) conducted the design review, and determined
that the existing venting between certain structural members is
inadequate to provide rapid equalization of the pressure differential
between the two sides of these members when rapid decompression occurs
on one side of the member. Inadequate venting of cabin pressure, if not
corrected, could cause failure or deformation of certain structural
members, and consequent reduced controllability of the airplane.
Explanation of Relevant Service Information
The FAA has reviewed and approved the following Raytheon Service
Bulletins:
1. Service Bulletin SB.21-151-25A683C, dated July 12, 1994
(Modification 25A683C), which describes procedures for installing a
pressure relief flap in the rear luggage compartment of the bulkhead at
frame 19. Installation of the pressure relief flap will limit the
pressure differential across the rear luggage compartment in the event
of rapid decompression of the airplane.
2. Service Bulletin SB.53-81-3661B, dated February 25, 1994
(Modification 253661B), which describes procedures to remove the
fiberglass infill cover located outboard of the floor panels between
frame 8 and frame 10B. This service bulletin also describes procedures
to increase the existing size of the lightening holes in the rail web
of the right-hand seat between frame 10B and frame 10D, and to add a
third hole to increase the vent area. Additionally, the service
bulletin describes procedures for installation of a new reinforcing
plate for all three lightening holes. Accomplishment of this
modification will ensure the structural integrity of the fuselage in
the event of rapid decompression of the airplane.
3. Service Bulletin SB.53-76-3627A, dated February 25, 1994
(Modification
[[Page 6505]]
253627A), which describes procedures for adding two holes to the
underfloor diaphragm at frame 10D (right-hand). Accomplishment of these
procedures increases the vent area between the cabin and the right-hand
underfloor area by 4 square inches. Accomplishment of this modification
will ensure the continued structural integrity of the fuselage in the
event of rapid decompression of the airplane.
Explanation of Requirements of Proposed Rule
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:
1. installing a pressure relief flap in the rear luggage
compartment of the bulkhead at frame 19;
2. enlarging two lightening holes and adding one new lightening
hole in the rail web of the right seat between frames 10B and 10D, and
removing fiberglass fill from the right support structure between frame
8 and frame 10B; and
3. installing two new vent holes in the underfloor diaphragm of
frame 10D (right hand).
The actions would be required to be accomplished in accordance with
the service bulletins described previously.
Cost Impact
The FAA estimates that 31 Model BAe 125-1000A and Model Hawker 1000
series airplanes of U.S. registry would be affected by this proposed
AD, that it would take approximately 44 work hours per airplane to
accomplish the proposed actions, 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 $81,840, or $2,640 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.
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:
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, Raytheon Corporate Jets,
British Aerospace, Hawker Siddeley, et al): Docket 96-NM-180-AD.
Applicability: All Model BAe 125-1000A and Model Hawker 1000
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
otherwise 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.
Note 2: Raytheon Model BAe 125-1000B series airplanes are
similar in design to the airplanes that are subject to the
requirements of this AD and, therefore, also may be subject to the
unsafe condition addressed by this AD. However, as of the effective
date of this AD, those models are not type certificated for
operation in the United States. Airworthiness authorities of
countries in which Model BAe 125-1000B series airplanes are approved
for operation should consider adopting corrective action, applicable
to those models, that is similar to the corrective action required
by this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent inadequate venting of cabin pressure in the event of
rapid decompression, which could cause failure or deformation of
certain structural members, and consequent reduced controllability
of the airplane, accomplish the following:
(a) Within 8 months after the effective date of this AD,
accomplish the requirements of paragraphs (a)(1), (a)(2), and (a)(3)
of this AD.
Note 3: The manufacturer has advised that the modifications
required by paragraphs (a)(2) and (a)(3) of this AD should be
incorporated concurrently.
(1) Install a pressure relief flap in the rear luggage
compartment of the bulkhead at frame 19 (Modification No. 25A683C),
in accordance with Raytheon Service Bulletin SB.21-151-25A683C,
dated July 12, 1994.
(2) Enlarge two lightening holes, and add one new lightening
hole in the rail web of the right-hand seat between frames 10B and
10D, and remove the fiberglass infill cover located outboard of the
floor panels between frame 8 and frame 10B (Modification
SB.253661B), in accordance with Raytheon Service Bulletin SB.53-81-
3661B, dated February 25, 1994.
(3) Install two new vent holes in the underfloor diaphragm of
frame 10D (Modification 253627A), in accordance with Raytheon
Service Bulletin SB.53-76-3627A, dated February 25, 1994.
(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, Standardization Branch, ANM-113,
FAA, Transport 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,
Standardization Branch, ANM-113.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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 February 5, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-3435 Filed 2-11-97; 8:45 am]
BILLING CODE 4910-13-U
