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.

Proposed Rules Federal Register

10224

Vol. 62, No. 44

Thursday, March 6, 1997

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–18–AD]

RIN 2120–AA64

Airworthiness Directives; Gulfstream

Aerospace Corporation Model G–159

(G–I) Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to all

Gulfstream Model G–159 (G–I)

airplanes, that currently requires

repetitive inspections to detect

corrosion in the wing planks under the

bottom wing center fairings, and repair,

if necessary. This action would require

the installation of a protective paint

system which, when accomplished, will

allow the inspections to be conducted at

longer intervals. This action was

prompted by the development of a

modification that will improve the

corrosion resistance of the subject area.

The actions specified by the proposed

AD are intended to detect and prevent

corrosion in the lower skins of the wing

center section. If corrosion in this area

remains unchecked, it could reduce the

integrity of the wing-to-fuselage fitting,

and consequently could lead to

separation of the wing from the

airplane.

DATES: Comments must be received by

April 14, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

18–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

Gulfstream Aerospace Corporation,

Technical Operations Department, P.O.

Box 2206, M/S D–10, Savannah, Georgia

31402–2206. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Christina Marsh, Aerospace Engineer,

Airframe and Propulsion Branch, ACE–

117A, FAA, Small Airplane Directorate,

Atlanta Aircraft Certification Office,

Campus Building, 1701 Columbia

Avenue, Suite 2–160, College Park,

Georgia 30337–2748; telephone (404)

305–7362; fax (404) 305–7348.

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 97–NM–18–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.

97–NM–18–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

In 1967, the FAA issued AD 67–04–

01, amendment 39–1234 (36 FR 12688,

July 3, 1971), applicable to all

Gulfstream Model G–159 (G–I)

airplanes. That AD requires a visual

inspection to detect corrosion of the

wing planks under the bottom wing

center fairing assemblies (having part

numbers 159W10400–121 and

159W10401–121), and repair if

necessary. After the initial inspection is

accomplished, and after any repair is

made, the inspection is required to be

repeated at intervals of 26 weeks.

That action was prompted by reports

indicating that corrosion was found in

the lower skins of the wing center

section of several of these airplanes. The

requirements of that AD are intended to

detect and correct corrosion in this area.

If such corrosion remains unchecked, it

could reduce the integrity of the wingto-fuselage fitting, and consequently

could lead to separation of the wing

from the airplane.

Actions Since Issuance of Previous Rule

As part of its on-going program to

address issues relevant to the continued

operational safety of the aging transport

fleet, the FAA, along with Gulfstream

Aerospace Corporation and several U.S.

and non-U.S. operators of the affected

airplanes, agreed to undertake the task

of identifying and implementing

procedures to ensure the continuing

structural airworthiness of aging

commuter-class airplanes. This group

recently reviewed selected service

bulletins, applicable to Gulfstream

Model G–159 airplanes, to be

recommended for mandatory

rulemaking action to ensure the

continued operational safety of these

airplanes.

Explanation of Relevant Service

Information

The group reviewed and

recommended Grumman Gulfstream I

Aircraft Service Change No. 190, dated

June 28, 1971, for mandatory regulatory

action. That service change describes

procedures for repetitive inspections to

detect corrosion of the center section

lower wing planks, and repair, if

necessary. It also describes the
Federal Register / Vol. 62, No. 44 / Thursday, March 6, 1997 / Proposed Rules 10225

installation of a protective paint system

to the fairing assemblies and bottom

wing cover. This protective system is

intended to improve the corrosion

resistance of this area. Once it is

installed, the repetitive inspections may

be conducted at longer intervals.

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

supersede AD 67–04–01. It would

continue to require the repetitive visual

inspections, specified in AD 67–04–01,

to detect corrosion of the wing planks

under the bottom wing center fairing

assemblies, and repair, if necessary.

For airplanes on which a protective

paint system had not been installed

previously, this new action would

require that the inspection continue to

be repeated at intervals of 6 months (26

weeks), until a protective paint system

is installed within 12 months. Once the

paint system is installed, the repetitive

inspections would be required to

continue, but the repetitive interval

would be extended to 18 months.

For airplanes on which a protective

paint system was installed previously,

this new action would extend the

currently-required repetitive inspection

interval of 12 months to 18 months.

These actions would be required to be

accomplished in accordance with the

aircraft service change described

previously.

Cost Impact

There are approximately 146

Gulfstream Model G–159 airplanes of

the affected design in the worldwide

fleet. The FAA estimates that 72

airplanes of U.S. registry would be

affected by this proposed AD.

The inspections that are currently

required by AD 67–04–01, and those

that would be required by this proposed

action, take approximately 40 work

hours per airplane to accomplish, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of the proposed inspection actions on

U.S. operators is estimated to be

$172,800, or $2,400 per airplane, per

inspection.

The installation of the protective

paint system that is proposed in this AD

action would take approximately 30

work hours per airplane to accomplish,

at an average labor rate of $60 per work

hour. Required materials would cost

approximately $100 per airplane. Based

on these figures, the cost impact of the

proposed requirements of this AD on

U.S. operators is estimated to be

$136,800, or $1,900 per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the current or 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

removing amendment 39–1234 (36 FR

12688, July 3, 1971), and by adding a

new airworthiness directive (AD), to

read as follows:

Gulfstream Aerospace Corporation: Docket

97–NM–18–AD. Supersedes AD 67–04–

01, Amendment 39–1234.

Applicability: All Model G–159 (G–I)

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 (d)(1) 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 detect and prevent corrosion in the

lower skins of the wing center section, which

could reduce the integrity of the wing-tofuselage fitting and consequently could lead

to separation of the wing from the airplane,

accomplish the following:

(a) For all airplanes: Within 4 weeks after

July 3, 1971 (the effective date of AD 67–04–

01, amendment 39–1234), remove the bottom

wing center fairings having part numbers (P/

N) 159W10400–121 and 159W10401–121, or

use an FAA-approved equivalent method, to

perform a visual inspection to detect

corrosion of the wing planks under these

fairings.

Note 2: Paragraph (a) of this AD merely

restates the actions previously required by

AD 67–04–01, amendment 39–1234. As

allowed by the phrase, ‘‘unless accomplished

previously,’’ if those requirements of AD 67–

04–01 have already been accomplished, this

AD does not require that those actions be

repeated.

Note 3: Care must be exercised when

removing the fairings, since the attaching

rivets go into the pressure vessel. Use caution

not to enlarge rivet holes when removing

rivets. When reinstalling the fairings, an

adequate type fastener and sealant must be

used.

Note 4: Grumman Service Newsletter,

Volume 166, dated August–September 1966,

pertains to this subject.

(b) For airplanes on which a protective

paint system has not been installed in

accordance with Grumman Gulfstream I

Aircraft Service Change No. 190, dated June

28, 1971: Accomplish paragraphs (b)(1) and

(b)(2) of this AD. As of the effective date of

this AD, the inspections required by this

paragraph shall be accomplished in

accordance with Grumman Gulfstream I

Aircraft Service Change No. 190, dated June

28, 1971.

Note 5: The repeated inspection referred to

in this paragraph is the same inspection

previously required by AD 67–04–01.

Paragraph (b)(1) of this AD merely restates
10226 Federal Register / Vol. 62, No. 44 / Thursday, March 6, 1997 / Proposed Rules

the requirement of AD 67–04–01 to repeat the

inspection at intervals of 6 months.

Paragraph (b)(2) permits the reinspection

interval to be extended to 18 months once the

specified protective paint system is installed.

(1) As a result of the inspection required

by paragraph (a) of this AD:

(i) If no corrosion is detected, repeat the

inspection thereafter at intervals not to

exceed 6 months (26 weeks) until the actions

specified in paragraph (b)(2) of this AD are

accomplished.

(ii) If any corrosion is detected, prior to

further flight, either repair the corroded part

with an FAA-approved repair; or replace the

corroded part with a new or serviceable part

of the same part number; or replace the

corroded part with a part approved by the

FAA. Thereafter, continue to perform the

inspection at intervals not to exceed 6

months (26 weeks) until paragraph (b)(2) of

this AD is accomplished.

(2) Within 12 months after the effective

date of this AD, install the protective paint

system in accordance with Grumman

Gulfstream I Aircraft Service Change No. 190,

dated June 28, 1971. After installation,

continue to perform the inspection required

by this paragraph at intervals not to exceed

18 months.

(c) For airplanes on which a protective

paint system has been installed previously in

accordance with Grumman Gulfstream I

Aircraft Service Change No. 190, dated June

28, 1971: Accomplish paragraphs (c)(1) and

(c)(2) of this AD. As of the effective date of

this AD, the inspections required by this

paragraph shall be accomplished in

accordance with Grumman Gulfstream I

Aircraft Service Change No. 190, dated June

28, 1971.

Note 6: The repeated inspection referred to

in this paragraph is the same inspection

previously required by AD 67–04–01.

Paragraph (c)(1) of this AD merely restates

the requirement of AD 67–04–01 to repeat the

inspection at intervals of 12 months.

Paragraph (c)(2) permits the reinspection

interval to be extended to 18 months.

(1) As a result of the inspection required

by paragraph (a) of this AD:

(i) If no corrosion is detected, repeat the

inspection thereafter at intervals not to

exceed 12 months until paragraph (c)(2) of

this AD is accomplished.

(ii) If any corrosion is detected, prior to

further flight, either repair the corroded part

with an FAA-approved repair; or replace the

corroded part with a new or serviceable part

of the same part number; or replace the

corroded part with a part approved by the

FAA. Thereafter, continue to perform the

inspection at intervals not to exceed 12

months until paragraph (c)(2) of this AD is

accomplished.

(2) Within 18 months since the last

inspection accomplished in accordance with

paragraph (c)(1) of this AD (i.e., the last

inspection accomplished in accordance with

AD 67–04–01), repeat the inspection

specified in paragraph (c)(1) of this AD.

(i) If no corrosion is detected, repeat the

inspection thereafter at intervals not to

exceed 18 months.

(ii) If any corrosion is detected, prior to

further flight, repair in accordance with the

service change. After repair, continue to

perform the inspection at intervals not to

exceed 18 months.

(d)(1) 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, Atlanta

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, Atlanta ACO.

(2) Alternative methods of compliance,

approved previously in accordance with AD

67–04–01, amendment 39–1234, are

approved as alternative methods of

compliance with this AD.

Note 7: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Atlanta ACO.

(e) 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 27, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–5463 Filed 3–5–97; 8:45 am]

BILLING CODE 4910–13–U

14 CFR Part 39

[Docket No. 97–NM–19–AD]

RIN 2120–AA64

Airworthiness Directives; Gulfstream

Aerospace Corporation Model G–159

(G–I) Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to certain

Gulfstream Model G–159 (G–I)

airplanes, that currently requires

repetitive inspections to detect chafe

wear on the upper diagonal engine

mount tube, and replacement or repair,

if necessary. This action would require

the installation of chafe guards at the

engine mounts, which would terminate

the currently required inspections. It

also would require that the chafe guards

then be repetitively inspected for chafe

wear. This proposal is prompted by the

development of a modification that will

provide better protection of the subject

area against future chafe wear. The

actions specified by the proposed AD

are intended to prevent excessive chafe

wear in the area of the upper diagonal

engine mount tubes and trusses; if not

detected and corrected, such wear could

result in failure of the engine mount

assembly and possible separation of the

engine from the airplane.

DATES: Comments must be received by

April 14, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

19–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

Gulfstream Aerospace Corporation,

Technical Operations Department, P.O.

Box 2206, M/S D–10, Savannah, Georgia

31402–2206. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Christina Marsh, Aerospace Engineer,

Airframe and Propulsion Branch, ACE–

117A, FAA Small Airplane Directorate,

Atlanta Aircraft Certification Office,

Campus Building, 1701 Columbia

Avenue, Suite 2–160, College Park,

Georgia 30337–2748; telephone (404)

305–7362; fax (404) 305–7348.

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