Federal Register / Vol. 63, No. 110 /Tuesday, June 9, 1998 / Proposed Rules 31377

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 action (1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under 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 has been placed 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 a new airworthiness directive

(AD) to read as follows:

Glaser-Dirks Flugzeugbau GMBH: Docket

No. 98–CE–12–AD. Applicability: Model

DG–400 gliders, serial numbers 4–1

through 4–249, certificated in any

category.

Note 1: This AD applies to each glider

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

gliders 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 (c) 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 within 1 calendar

month after the effective date of this AD,

unless already accomplished.

To prevent damage to the engine caused by

vibration, which could result in loss of

engine power during critical phases of flight,

accomplish the following:

(a) Inspect the powerplant (engine) mount

and propeller mount for any loose parts in

accordance with paragraph 1 in the

Instructions section of Glaser-Dirks Technical

Note (TN) Nr. 826/22, dated January 10,

1990.

(1) If any part of the powerplant mount or

propeller mount is found loose, prior to

further flight, accomplish paragraphs 2

through 4 in the Instructions section of

Glaser-Dirks TN Nr. 826/22, dated January

10, 1990. The engine ignition timing

procedures shall be accomplished in

accordance with the appropriate Bombardier

ROTAX maintenance manual for ROTAX

engine type 505, which is referenced in

Working Instruction No. 3, Instruction 4 of

the Glaser-Dirks TN Nr. 826/22.

(2) If no part of the powerplant mount or

propeller mount is loose upon the inspection

required in paragraph (a) of this AD,

accomplish paragraphs 2 through 4 in the

Instructions section of Glaser-Dirks TN Nr.

826/22, dated January 10, 1990, within the

next 3 calendar months after the date of the

initial inspection.

Note 2: It is recommended that the manual

pages referenced in the Instructions section

of Glaser-Dirks TN Nr. 826/22 be inserted

into the maintenance manual.

(b) 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 glider to a

location where the requirements of this AD

can be accomplished.

(c) An alternative method of compliance or

adjustment of the compliance time that

provides an equivalent level of safety may be

approved by the Manager, Small Airplane

Directorate, FAA, 1201 Walnut, suite 900,

Kansas City, Missouri 64106. The request

shall be forwarded through an appropriate

FAA Maintenance Inspector, who may add

comments and then send it to the Manager,

Small Airplane Directorate.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Small Airplane

Directorate.

(d) Questions or technical information

related to DG Flugzeugbau Technical Note

No. 826/22, dated January 10, 1990, should

be directed to DG Flugzeugbau GmbH, P.O.

Box 4120, 76625 Bruchsal, Germany;

telephone: +49 7257–89–0; facsimile: +49

7257–8922. This service information may be

examined at the FAA, Central Region, Office

of the Regional Counsel, Room 1558, 601 E.

12th Street, Kansas City, Missouri 64106.

Note 4: The subject of this AD is addressed

in German AD 90–43 Glaser-Dirks, dated

February 26, 1990.

Issued in Kansas City, Missouri, on June 1,

1998.

Ronald K. Rathgeber,

Acting Manager, Small Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 98–15197 Filed 6–8–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–116–AD]

RIN 2120–AA64

Airworthiness Directives; Bombardier

Model CL–600–2B19 (Regional Jet

Series 100 and 200) 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

Bombardier Model CL–600–2B19

(Regional Jet Series 100 and 200)

airplanes, that currently requires

repetitive inspections to detect

discrepancies of the shock strut end

caps and attachment pins of the main

landing gear (MLG), and replacement of

discrepant parts with new parts. It also

requires a check for and replacement of

certain pins that currently may be

installed on some airplanes. This action

would add a requirement for the

installation of new, improved MLG

shock strut upper and lower attachment

pins, which would constitute

terminating action for the repetitive

inspections. This action also would

reduce the applicability of the existing

AD by removing certain airplanes. 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

attachment pins and the attachment pin

end caps, which could result in failure

of the MLG.

DATES: Comments must be received by

July 9, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 97–NM–

116–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00
31378 Federal Register / Vol. 63, No. 110 /Tuesday, June 9, 1998 / Proposed Rules

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Bombardier, Inc., Canadair, Aerospace

Group, P.O. Box 6087, Station Centreville, Montreal, Quebec H3C 3G9,

Canada; or Messier-Dowty Inc., 574

Monarch Avenue, Ajax, Ontario L1S

2GB, Canada. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington; or at

the FAA, Engine and Propeller

Directorate, New York Aircraft

Certification Office, 181 South Franklin

Avenue, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT:

George Duckett, Aerospace Engineer,

Airframe and Propulsion Branch, ANE–

171, FAA, New York Aircraft

Certification Office, Engine and

Propeller Directorate, 10 Fifth Street,

Third Floor, Valley Stream, New York

11581; telephone (516) 256–7525; fax

(516) 256–2716.

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–116–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.

97–NM–116–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On October 24, 1996, the FAA issued

AD 96–22–14, amendment 39–9803 (61

FR 57319, November 6, 1996),

applicable to certain Bombardier Model

CL–600–2B19 (Regional Jet Series 100

and 200) airplanes, to require repetitive

inspections to detect discrepancies of

the shock strut end caps and attachment

pins of the main landing gear (MLG),

and replacement of discrepant parts

with new parts. It also requires a check

for and replacement of certain pins that

currently may be installed on some

airplanes.

That action was prompted by reports

of corrosion, wear, and loss of chrome

plating on the upper and lower

attachment pins of the shock strut of the

MLG, and reports of cracks in the lower

attachment pins and the end cap of

upper attachment pins. The

requirements of that AD are intended to

prevent failure of the attachment pin

and the attachment pin end caps, which

could result in failure of the MLG.

Actions Since Issuance of Previous Rule

In the preamble to AD 96–22–14, the

FAA specified that the actions required

by that AD were considered ‘‘interim

action’’ and that once a terminating

modification is developed, approved,

and available, the FAA may consider

additional rulemaking action. The

manufacturer now has developed such a

modification, and the FAA has

determined that further rulemaking

action is indeed necessary; this

proposed AD follows from that

determination.

Relevant Service Information

The manufacturer has issued Canadair

Regional Jet Service Bulletin S.B. 601R–

32–065, dated November 11, 1996. The

Canadair service bulletin references

Messier-Dowty Service Bulletin M–DT

17002–32–12, dated November 6, 1996,

as an additional source of service

information. These service bulletins

describe procedures for the installation

of new, improved MLG shock strut

upper and lower attachment pins. The

effectivity listing of the Canadair service

bulletin limits the accomplishment of

the installation to those airplanes on

which the installation was not

accomplished during production.

Accomplishment of the installation

eliminates the need for the repetitive

inspections required by AD 96–22–14.

Transport Canada Aviation (TCA),

which is the airworthiness authority for

Canada, classified the Canadair service

bulletin as mandatory and issued

Canadian airworthiness directive CF–

96–12R1, dated January 29, 1997, in

order to assure the continued

airworthiness of these airplanes in

Canada.

FAA’s Conclusions

This airplane model is manufactured

in Canada 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,

TCA has kept the FAA informed of the

situation described above. The FAA has

examined the findings of TCA, 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

supersede AD 96–22–14 to continue to

require the repetitive inspections to

detect discrepancies of the shock strut

end caps and attachment pins of the

MLG. It also continues to require a

check for and replacement of certain

pins that currently may be installed on

some airplanes. This new proposed AD

would add a requirement for the

installation of new, improved MLG

shock strut upper and lower attachment

pins, which would constitute

terminating action for the repetitive

inspections. In addition, this action

would reduce the applicability of the

existing AD by removing certain

airplanes.

The actions would be required to be

accomplished in accordance with the

service bulletin described previously.

Cost Impact

There are approximately 41 Model

CL–600–2B19 (Regional Jet Series 100

and 200) airplanes of U.S. registry that

would be affected by this proposed AD.

The actions that are currently

required by AD 96–22–14, and retained

in this proposed AD, take approximately

25 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 currently

required actions on U.S. operators is

estimated to be $61,500, or $1,500 per

airplane.
Federal Register / Vol. 63, No. 110 /Tuesday, June 9, 1998 / Proposed Rules 31379

The new actions that are proposed in

this AD action would take

approximately 13 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour.

Required parts would be supplied by

the manufacturer at no cost to the

operators. Based on these figures, the

cost impact of the new actions proposed

by this AD on U.S. operators is

estimated to be $31,980, or $780 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 39–9803 (61 FR

57319, November 6, 1996), and by

adding a new airworthiness directive

(AD), to read as follows:

Bombardier, Inc. (Formerly Canadair):

Docket 97–NM–116–AD. Supersedes AD

96–22–14, Amendment 39–9803.

Applicability: Model CL–600–2B19

(Regional Jet Series 100 and 200) airplanes,

serial numbers 7003 through 7157 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 (f) 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 attachment pins and

the attachment pin end caps of the main

landing gear (MLG), which could result in

failure of the MLG, accomplish the following:

Restatement of the Requirements of AD 96–

22–14

(a) Serial Number Check. For airplanes

having serial numbers 7003 through 7126

inclusive: Within 150 landings after

November 21, 1996 (the effective date of AD

96–22–14, amendment 39–9803), check the

serial number of each MLG shock strut lower

attachment pin, part number 17144–1, in

accordance with paragraphs 2.A. and 2.B. of

the Accomplishment Instructions of Canadair

Regional Jet Alert Service Bulletin S.B.

A601R–32–062, Revision ‘C,’ dated

September 18, 1996; and paragraphs 2.A.(4),

2.B.(4), and 2.C.(3) of the Accomplishment

Instructions of Messier-Dowty Service

BulletinM–DT 17002–32–10, Revision 3,

dated September 6, 1996.

(1) If the serial number is within the range

of DCL206 through DCL259 inclusive, prior

to further flight, remove the pin and install

a new pin having a serial number outside

(either higher or lower) of that range, in

accordance with the service bulletins.

Thereafter, inspect that replacement pin in

accordance with paragraphs (b) and (c) of this

AD.

(2) If the serial number is outside of the

range (higher or lower) of DCL206 through

DCL259 inclusive, thereafter inspect the pin

in accordance with paragraphs (b) and (c) of

this AD.

(b) In-Situ Visual Inspection. Within 150

landings after November 21, 1996, perform

an in-situ visual inspection to detect

discrepancies of the left- and right-hand

shock strut of the MLG, in accordance with

paragraphs 2.C. and 2.D. of the

Accomplishment Instructions of Canadair

Regional Jet Alert Service Bulletin S.B.

A601R–32–062, Revision ‘C,’ dated

September 18, 1996; and paragraph 2.B.(1) of

the Accomplishment Instructions of MessierDowty Service Bulletin M–DT 17002–32–10,

Revision 3, dated September 6, 1996.

Note 2: In-situ visual inspections that have

been accomplished prior to November 21,

1996, in accordance with Messier-Dowty

Service Bulletin M–DT 17002–32–10, dated

June 13, 1996; Revision 1, dated June 29,

1996; or Revision 2, dated July 17, 1996; are

considered acceptable for compliance with

paragraph (b) of this amendment.

(1) If no discrepancy is detected, repeat the

in-situ visual inspection thereafter at

intervals not to exceed every ‘‘A’’ check or

400 landings, whichever occurs later.

(2) If any discrepancy is detected, prior to

further flight, replace the discrepant part

with a new part in accordance with the

service bulletins. Thereafter, repeat the insitu visual inspection at intervals not to

exceed every ‘‘A’’ check or 400 landings,

whichever occurs later.

(c) Detailed Inspection. Within 3,000

landings since the date of airplane

manufacture, or within 400 landings after

November 21, 1996, whichever occurs later,

perform a detailed inspection to detect

discrepancies of the shock strut end caps and

attachment pins of the MLG, in accordance

with paragraphs 2.E. and 2.F. of the

Accomplishment Instructions of Canadair

Regional Jet Alert Service Bulletin S.B.

A601R–32–062, Revision ‘C,’ dated

September 18, 1996; and paragraph 2.B.(2) of

the Accomplishment Instructions of MessierDowty Service Bulletin M–DT 17002–32–10,

Revision 3, dated September 6, 1996. Nondestructive testing (NDT) must be

accomplished in accordance with the

instructions provided or references referred

to in these service bulletins. Where

instructions in those documents specify dye

penetrant inspections (DPI), accomplish

fluorescent penetrant (Type 1) inspections,

sensitivity level 3 or higher, using material

qualified to Military Standard MIL–I–25135.

Note 3: Detailed inspections accomplished

prior to November 21, 1996, in accordance

with Messier-Dowty Service Bulletin M–DT

17002–32–10, dated June 13, 1996; Revision

1, dated June 29, 1996; or Revision 2, dated

July 17, 1996; are considered acceptable for

compliance with paragraph (c) of this

amendment.

(1) If no discrepancy is detected, repeat the

detailed inspection thereafter at intervals not

to exceed 2,000 landings.

(2) If any discrepancy is detected, prior to

further flight, replace the discrepant part

with a new part in accordance with the

service bulletins. Repeat the detailed

inspection thereafter at intervals not to

exceed 2,000 landings.

(d) As of November 21, 1996, no person

shall install on any airplane an MLG shock

strut lower attachment pin, part number

17144–1, that has a serial number that is

within the range of DCL206 through DCL259

inclusive.
31380 Federal Register / Vol. 63, No. 110 /Tuesday, June 9, 1998 / Proposed Rules

New Requirements of This AD

(e) Within 6 months after the effective

date of this AD, install new MLG shock

strut upper and lower attachment pins

in accordance with Canadair Regional

Jet Service Bulletin S.B. 601R–32–065,

dated November 11, 1996.

Accomplishment of this installation

constitutes terminating action for the

repetitive inspections required by

paragraphs (b) and (c) of this AD.

Note 4: The Canadair service bulletin

references Messier-Dowty Service Bulletin

M–DT 17002–32–12, dated November 6,

1996, as an additional source of service

information to accomplish the installation.

(f)(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, New York

Aircraft Certification Office (ACO), FAA,

Engine and Propeller Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, New York ACO.

(2) Alternative methods of compliance,

approved previously in accordance with AD

96–22–14, amendment 39–9803, are

approved as alternative methods of

compliance with this AD.

Note 5: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the New York ACO.

(g) 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 6: The subject of this AD is addressed

in Canadian airworthiness directive CF–96–

12R1, dated January 29, 1997.

Issued in Renton, Washington, on June 3,

1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–15252 Filed 6–8–98; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–151–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

a one-time inspection for cracking of the

rear pressure bulkhead; and installation

of a reinforcement angle on the rear

pressure bulkhead; or repair, 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 cracking of the

rear pressure bulkhead, which could

result in sudden loss of cabin pressure

and the inability to withstand fail-safe

loads.

DATES: Comments must be received by

July 9, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 98–NM–

151–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

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 98–NM–151–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–151–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The Luftfartsverket (LFV), which is

the airworthiness authority for Sweden,

notified the FAA that an unsafe

condition may exist on certain Saab

Model SAAB 2000 series airplanes. The

LFV advises that, during full-scale

fatigue testing on a test article, a crack

was detected on the radius of the lower

forward flange that connects the rear

pressure bulkhead to the fuselage skin.

The crack occurred when the test article

reached 68,000 simulated flights. The

LFV further advises that reinforcement

of the lower forward flange area that

connects the rear pressure bulkhead to

the fuselage skin is required to meet the

design life of the airplane. Such

cracking, if not corrected, could result

in sudden loss of cabin pressure and the

inability to withstand fail-safe loads.

Explanation of Relevant Service

Information

The manufacturer has issued SAAB

Service Bulletin 2000–53–026, dated

February 27, 1998, which describes

procedures for a one-time inspection to

detect cracking of the rear pressure

bulkhead in the area of the lower

forward flange that connects to the

fuselage skin. Additionally, for

airplanes on which no cracking is

found, the service bulletin describes

procedures for installation of a

reinforcement angle on the rear pressure

bulkhead in the area of the lower

forward flange that connects to the

fuselage skin. Accomplishment of the

actions specified in the service bulletin

is intended to adequately address the

identified unsafe condition. The LFV

classified this service bulletin as

mandatory and issued Swedish

airworthiness directive 1–122, dated

March 2, 1998, in order to assure the