6504 Federal Register / Vol. 62, No. 29 / Wednesday, February 12, 1997 / Proposed Rules

further flight after accomplishing this

installation, remove the AFM revision

required by paragraphs (a) of this AD.

(c) 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, Manager,

Standardization Branch, ANM–113, FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Operations

Inspector, who may add comments and then

send it to the Manager, Standardization

Branch, ANM–113.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(d) 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. 97–3434 Filed 2–11–97; 8:45 am]

BILLING CODE 4910–13–U

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).

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
Federal Register / Vol. 62, No. 29 / Wednesday, February 12, 1997 / Proposed Rules 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.

§ 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