Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules 30023

airplane, an H–11 steel bolt, part number

71658–8–44, 71658–7–44, 71658–7–54,

71658–7–56, 71658–7–29, 71658–9–31,

71658–9–34, 71658–9–38, 71658–9–41,

71658–10–41, 71658–7–26, 71658–7–27, or

71658–8–29, on the inboard or outboard flap

assembly.

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, Los

Angeles Aircraft Certification Office (ACO),

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, Los Angeles ACO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

Special Flight Permits

(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 May 4,

2000.

Vi L. Lipski,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–11724 Filed 5–9–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–368–AD]

RIN 2120–AA64

Airworthiness Directives; Saab Model

SAAB 2000 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

certain Saab Model SAAB 2000 series

airplanes. This proposal would require

repetitive detailed visual and dye

penetrant inspections of the backup

struts in the left and right nacelles to

detect discrepancies; and corrective

actions, if necessary. This proposal is

prompted by issuance of mandatory

continuing airworthiness information by

a foreign civil airworthiness authority.

The actions specified by the proposed

AD are intended to prevent failure of the

backup struts in the left and right

nacelles due to fatigue cracking, which

could result in loss of fail-safe

redundancy in the design of the nacelle

in terms of load capability.

DATES: Comments must be received by

June 9, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–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

Saab Aircraft AB, SAAB Aircraft

Product Support, S–581.88, Linko ̈ping,

Sweden. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Norman B. Martenson, Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2110;

fax (425) 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 Number 99–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.

99–NM–368–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The Luftfartsverket (LFV), which is

the airworthiness authority for Sweden,

recently notified the FAA that an unsafe

condition may exist on certain Saab

Model SAAB 2000 series airplanes. The

LFV advises that field experience has

revealed fatigue cracking in the internal

backup struts in the forward part of the

nacelle structure. Such cracking was

found in the area of the welded splices

for the upper and lower attachment

fittings. In the lower end of the

attachment fittings, cracks were found

near the local cut-out in the tube or

areas adjacent to the welding, and in the

upper area in the radius of the

attachment fittings. On one occasion,

fatigue cracks resulted in complete

failure of the backup strut. Such fatigue

cracking, if not corrected, could result

in failure of the backup struts in the left

and right nacelles, which could result in

loss of fail-safe redundancy in the

design of the nacelle in terms of load

capability.

Explanation of Relevant Service

Information

The manufacturer has issued Saab

Service Bulletin 2000–54–023, Revision

01, dated January 28, 2000, which

describes procedures for repetitive

detailed visual and dye penetrant

inspections of the backup struts in the

left and right nacelles to detect

discrepancies; and corrective actions, if

necessary. Descriptions of the two types

of inspections are as follows:

• The initial detailed visual

inspection includes the upper areas of

the backup strut around the welding in

the pipe and in the attachment fittings.

• The initial dye penetrant

inspection, using a Penetrant Type 1

(fluorescent dye) sensitivity level 2,

includes the lower areas of the backup

strut around the welding in the pipe and

in the attachment fittings, and specifies

taking special care to check the inside

edge of the cutouts.

If any inspection reveals a failed

backup strut, procedures include the

following additional inspections of the

engine mount surrounding structure:

• Detailed visual inspections of each

engine mount strut and mounting

30024 Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules

fittings, forward semi-circular collar/

frame and aft beam, nacelle backup strut

opposite side to the failed backup strut

and attachment fittings at station 176/

199, inboard and outboard upper and

lower longerons of the nacelle, and

upper and lower longerons at the

attachment to the inboard and outboard

upper and lower fittings of the nacelle.

• General visual inspections of the

inner and outer side walls and side of

the skin panels.

Discrepancies include fatigue

cracking, a failed backup strut, and

damage to the surrounding structure of

the engine mount. Corrective actions

include replacing any failed backup

strut located in the hydraulic bay or

electrical bay areas with a new backup

strut, and performing additional

inspections of the surrounding structure

of the engine mount.

The LFV classified this service

bulletin as mandatory and issued

Swedish airworthiness directive No. 1–

150R1, dated January 31, 2000, in order

to assure the continued airworthiness of

these airplanes in Sweden.

FAA’s Conclusions

This airplane model is manufactured

in Sweden and is type certificated for

operation in the United States under the

provisions of section 21.29 of the

Federal Aviation Regulations (14 CFR

21.29) and the applicable bilateral

airworthiness agreement. Pursuant to

this bilateral airworthiness agreement,

the LFV has kept the FAA informed of

the situation described above. The FAA

has examined the findings of the LFV,

reviewed all available information, and

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

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

accomplishment of the actions specified

in the service bulletin described

previously, except as described below.

Differences Between Proposed AD and

Service Bulletin

Operators should note that, although

the service bulletin specifies that the

manufacturer may be contacted for

repair instructions for certain damage

conditions, this proposed AD would

require the repair of those conditions to

be accomplished in accordance with a

method approved by either the FAA or

the LFV (or its delegated agent). In light

of the type of repair that would be

required to address the identified unsafe

condition, and in consonance with

existing bilateral airworthiness

agreements, the FAA has determined

that a repair approved by either the FAA

or the LFV would be acceptable for

compliance with this proposed AD.

Interim Action

This is considered to be interim

action until final action is identified, at

which time the FAA may consider

further rulemaking.

Cost Impact

The FAA estimates that 3 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

inspections, 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 $1,440, or $480 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.

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.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

SAAB Aircraft AB: Docket 99–NM–368–AD.

Applicability: Model SAAB 2000 series

airplanes, serial numbers –004 through –063

inclusive; 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 failure of the backup struts in

the left and right nacelles due to fatigue

cracking, which could result in loss of failsafe redundancy in the design of the nacelle

in terms of load capability, accomplish the

following:

Repetitive Inspections

(a) For airplanes on which the dye

penetrant inspection of the backup struts in

the left and right nacelles specified in Saab

Alert Service Bulletin 2000–A54–022, dated

October 27, 1999, has not been

accomplished prior to the effective date of

this AD:

Within 200 flight hours after the effective

date of this AD, accomplish paragraphs (b)(1)

and (b)(2) of this AD in accordance with the

Accomplishment Instructions of Saab Service

Bulletin 2000–54–023, Revision 01, dated

January 28, 2000.

(b) For airplanes on which the dye

penetrant inspection of the backup struts in

the left and right nacelle specified in Saab

Alert Service Bulletin 2000–A54–022, dated

October 27, 1999, has been accomplished

prior to the effective date of this AD: Within

450 flight hours after the effective date of this

AD, accomplish paragraphs (b)(1) and (b)(2)

of this AD in accordance with the

Accomplishment Instructions of Saab Service

Bulletin 2000–54–023, Revision 01, dated

January 28, 2000.

Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules 30025

(1) Perform a detailed visual inspection of

the upper areas of the backup strut around

the welding in the pipe and in the

attachment fittings to detect any discrepancy

(including fatigue cracking or a failed backup

strut) by accomplishing all actions specified

in paragraph B.(1) of the Accomplishment

Instructions of the service bulletin, in

accordance with that service bulletin. Repeat

the detailed visual inspection thereafter at

intervals not to exceed 450 flight hours.

Note 2: For the purposes of this AD, a

detailed visual inspection is defined as: ‘‘An

intensive visual examination of a specific

structural area, system, installation, or

assembly to detect damage, failure, or

irregularity. Available lighting is normally

supplemented with a direct source of good

lighting at intensity deemed appropriate by

the inspector. Inspection aids (e.g., mirror,

magnifying lenses) may be used. Surface

cleaning and elaborate access procedures

may be required.’’

(2) Perform a dye penetrant inspection,

using Penetrant Type 1 (fluorescent dye)

sensitivity level 2, of the lower areas of the

backup strut around the welding in the pipe

and in the attachment fittings to detect any

discrepancy (including fatigue cracking or a

failed backup strut) by accomplishing all

actions specified in paragraphs B.(2) and

B.(3) of the service bulletin, as applicable, in

accordance with that service bulletin.

(i) For airplanes on which all backup struts

have accumulated less than 4,500 total flight

hours as of the effective date of this AD,

repeat the dye penetrant inspection thereafter

at intervals not to exceed 1,650 flight hours,

until any backup strut on the airplane has

accumulated 4,500 total flight hours; then

perform the repetitive inspection thereafter at

the interval specified by paragraph (b)(2)(ii)

of this AD.

(ii) For airplanes on which any backup

strut has accumulated 4,500 or more total

flight hours as of the effective date of this

AD, repeat the dye penetrant inspection

thereafter at intervals not to exceed 900 flight

hours.

Corrective Actions

(c) If any discrepancy (including fatigue

cracking, a failed backup strut, or damage to

the surrounding structure of the engine

mount) is detected during any inspection

required by this AD: Prior to further flight,

accomplish the applicable corrective actions

(including performing additional inspections

of the engine mount surrounding structure,

and replacing any discrepant backup strut in

the hydraulic or electrical bay areas with a

new backup strut) specified by paragraph C.

of the Accomplishment Instructions of Saab

Service Bulletin 2000–54–023, Revision 01,

dated January 28, 2000, in accordance with

that service bulletin. For any repair condition

for which the service bulletin specifies to

contact the manufacturer for appropriate

ACTION: Prior to further flight, repair in

accordance with a method approved by

either the Manager, International Branch,

ANM–116, FAA, Transport Airplane

Directorate; or the Luftfartsverket (LFV) (or

its delegated agent). For a repair method to

be approved by the Manager, International

Branch, ANM–116, as required by this

paragraph, the Manager’s approval letter

must specifically reference 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,

International Branch, ANM–116. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, International Branch,

ANM–116.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the International Branch,

ANM–116.

Special Flight Permits

(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.

Note 4: The subject of this AD is addressed

in Swedish airworthiness directive No. 1–

150R1, dated January 31, 2000.

Issued in Renton, Washington, on May 4,

2000.

Vi L. Lipski,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–11723 Filed 5–9–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–255–AD]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9–10, –20, –30, –40

and –50 Series Airplanes and C–9

(Military) 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

McDonnell Douglas Model DC–9 series

airplanes and C–9 (military) airplanes,

that currently requires repetitive

ultrasonic or magnetic particle

inspections to detect cracking of the

engine pylon aft upper spar straps

(caps); and if necessary, replacement of

the strap with a new strap, or

modification of the engine pylon rear

spar straps, which constitutes

terminating action for the repetitive

inspections. This action would require

new, improved repetitive ultrasonic

inspections, and corrective actions, if

necessary. This action also would

require, among other items, a

terminating action for the repetitive

inspection requirements. This proposal

is prompted by additional reports of

fatigue cracking in the subject area on

these airplanes. The actions specified by

the proposed AD are intended to detect

and correct such fatigue cracking, which

could result in major damage to the

adjacent structure of the pylon aft spar

upper cap, and consequent reduced

structural integrity of the airplane.

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. 99–NM–

255–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

Boeing Commercial Aircraft Group,

Long Beach Division, 3855 Lakewood

Boulevard, Long Beach, California

90846, Attention: Technical

Publications Business Administration,

Dept. C1-L51 (2–60). This information

may be examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington; or at

the FAA, Transport Airplane

Directorate, Los Angeles Aircraft

Certification Office, 3960 Paramount

Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Wahib Mina, Aerospace Engineer,

Airframe Branch, ANM–120L, FAA,

Transport Airplane Directorate, Los

Angeles Aircraft Certification Office,

3960 Paramount Boulevard, Lakewood,

California 90712–4137; telephone (562)

627–5324; fax (562) 627–5210.

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