10492 Federal Register / Vol. 62, No. 45 / Friday, March 7, 1997 / Proposed Rules

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 ensure continued structural integrity of

these airplanes, accomplish the following:

(a) Within 180 days after the effective date

of this AD, revise the Airworthiness

Limitations Section of the Instructions for

Continued Airworthiness [Airworthiness

Limitations Instructions (ALI), McDonnell

Douglas Report No. MDC–94K9000, dated

November 1994] to incorporate the Item,

Location, and Inspection Interval of the

following principal structural elements: This

may be accomplished by inserting a copy of

Revision 1 of the ALI, dated January 1995, or

a copy of this AD into the ALI.

Item Location

Inspection interval (in

landings)

Initial Repeat

Item 53.30.02.3 ..... Skin Panels, STA 237 to 1395 Fuselage Skin in Constant Section from Longeron 3 Left to

Longeron 3 Right.

60,000 11,000

Item 53.30.02.4 ..... Skin Panels, STA 237 to 1395 Fuselage Hoop Skin Splice in Constant Section from Longeron 5 Left to Longeron 5 Right.60,000 30,000

Item 54.10.04.1 ..... Thrust Bulkhead, Pylon—STA Yn 170.5—Rear Spar and Engine Thrust Support Fitting

(Upper and Lower).

15,000 4,500

(b) Within 180 days after the effective date of this AD, revise the Airworthiness Limitations Section of the Instructions

for Continued Airworthiness [Airworthiness Limitations Instructions (ALI), McDonnell Douglas Report No. MDC–94K9000,

dated November 1994] to incorporate the Item, Location, and Inspection Interval of the following principal structural

elements: This may be accomplished by inserting a copy of Revision 2 to the ALI, dated July 1996, or a copy of

this AD into the ALI.

Item Location

Inspection interval (in

landings)

Initial Repeat

Item 55.13.01.1 ..... Plates/Skin—Upper STA Xh 27.2 Left to Xh 27.2 Right—Upper Aft Skin Plank with Integral

Stringers from Xh 7.234 to Xh 26.859.

60,000 8,100

(c) Except as provided in paragraph

(d) of this AD: After the actions

specified in paragraphs (a) and (b) of

this AD have been accomplished, no

alternative inspections or inspection

intervals may be approved for the parts

specified in paragraphs (a) and (b) of

this AD.

(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.

(e) Special flight permits may be

issued in accordance with §§ 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

28, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–5573 Filed 3–6–97; 8:45 am]

BILLING CODE 4910–13–U

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–203–AD]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9 and DC–9–80

Series Airplanes, Model MD–88

Airplanes, and C–9 (Military) 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

McDonnell Douglas Model DC–9 and

DC–9–80 series airplanes, Model MD–88

airplanes, and C–9 (military) series

airplanes. This proposal would require

repetitive high frequency eddy current

inspections of the external areas of the

fuselage to detect cracks of the skin and/

or longeron, and various follow-on

actions. The proposal also would

require the installation of a preventative

modification, which would terminate

the repetitive inspections. This proposal

is prompted by reports indicating that,

due to material fatigue caused by

installation preload and cabin

pressurization cycles, fatigue cracks

were found in the skin and longerons of

the fuselage. The actions specified by

the proposed AD are intended to

prevent such fatigue cracks, which

could result in loss of the structural

integrity of the fuselage and,

consequently, lead to rapid

depressurization of the airplane.

DATES: Comments must be received by

April 16, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No.96–NM–

203–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this
Federal Register / Vol. 62, No. 45 / Friday, March 7, 1997 / Proposed Rules 10493

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

McDonnell Douglas Corporation, 3855

Lakewood Boulevard, Long Beach,

California 90846, Attention: Technical

Publications Business Administration,

Department C1–L51 (2–60). This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton,

Washington.

FOR FURTHER INFORMATION CONTACT:

Brent Bandley, Aerospace Engineer,

Airframe Branch, ANM–120L, FAA, Los

Angeles Aircraft Certification Office,

3960 Paramount Boulevard, Lakewood,

California 90712; telephone (310) 627–

5237; fax (310) 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

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 96–NM–203–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–203–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

The FAA has received several reports

indicating that, on certain McDonnell

Douglas Model DC–9 series airplanes,

cracks were found in the skin and

longerons of the fuselage. The cracked

fuselage skin was found on airplanes

that had accumulated 61,345 or more

total landings. The cracked fuselage

longerons were found on airplanes that

had accumulated 45,850 or more total

landings. The cracking occurred

between longeron 5 left and longeron 8

right, between stations Y=160.000 and

Y=218.000. Investigation revealed that

the apparent cause of such cracking has

been attributed to material fatigue, as a

result of installation preload and cabin

pressurization cycles. This condition, if

not detected and corrected in a timely

manner, could result in loss of the

structural integrity of the fuselage and,

consequently, lead to rapid

depressurization of the airplane.

The subject area on certain

McDonnell Douglas Model DC–9–80

series airplanes, Model MD–88

airplanes, and C–9 (military) series

airplanes is identical to that on the

affected Model DC–9 series airplanes.

Therefore, all of these airplanes may be

subject to the same unsafe condition.

Explanation of Relevant Service

Information

The FAA has reviewed and approved

McDonnell Douglas Service Bulletin 53–

235, dated September 15, 1993. The

service bulletin describes procedures for

performing repetitive high frequency

eddy current (HFEC) inspections of the

external areas of the fuselage skin to

detect cracks of the skin and/or

longeron between stations Y=160.000

and Y=218.000 and various follow-on

actions. (These follow-on actions

include repetitive inspections or

installation of a preventative

modification, and repair of cracked skin

or longerons.) The service bulletin also

describes procedures for installation of

a preventative modification, which

would eliminate the need for repetitive

inspections. The preventative

modification involves installation of

clips and doublers between certain

stations. Accomplishment of the

preventative modification will minimize

the possibility of further crack

development.

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

require repetitive HFEC inspections of

the external areas of the fuselage skin to

detect cracks of the skin and/or

longeron between stations Y=160.000

and Y=218.000, and various follow-on

actions. The proposed AD also would

require the installation of a preventative

modification, which would constitute

terminating action for the repetitive

inspection requirements. The actions

would be required to be accomplished

in accordance with the service bulletin

described previously.

Differences Between the Proposal and

the Referenced Service Information

This proposed AD would differ from

the referenced service bulletin in that it

would mandate the accomplishment of

the terminating preventative

modification for the repetitive

inspections. The service bulletin

provides that action only as optional

procedure.

Mandating the terminating action is

based on the FAA’s determination that

long term continued operational safety

will be better assured by modifications

or design changes to remove the source

of the problem, rather than by repetitive

inspections. Long term inspections may

not be providing the degree of safety

assurance necessary for the transport

airplane fleet. This, coupled with a

better understanding of the human

factors associated with numerous

repetitive inspections, has led the FAA

to consider placing less emphasis on

special procedures and more emphasis

on design improvements. The proposed

modification requirement is in

consonance with these considerations.

Cost Impact

There are approximately 1,728

McDonnell Douglas Model DC–9 and

DC–9–80 series airplanes, Model MD–88

airplanes, and C–9 (military) series

airplanes of the affected design in the

worldwide fleet. The FAA estimates that

1,152 airplanes of U.S. registry would be

affected by this proposed AD.

It would take approximately 16 work

hours per airplane to accomplish the

proposed HFEC inspection, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of the HFEC inspection proposed by this

AD on U.S. operators is estimated to be

$1,105,920, or $960 per airplane, per

inspection cycle.

It would take approximately 89 work

hours per airplane to accomplish the

proposed modification, at an average

labor rate of $60 per work hour. The

cost of required parts would range from

$13,771 to $15,292 per airplane. Based

on these figures, the cost impact of the

proposed AD on U.S. operators is

estimated to be between $22,015,872
10494 Federal Register / Vol. 62, No. 45 / Friday, March 7, 1997 / Proposed Rules

($19,111 per airplane) and $23,768,064

($20,632 per airplane).

The cost impact figures discussed

above are 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:

McDonnell Douglas: Docket 96–NM–203–

AD.

Applicability: Model DC–9–10, -20, -30,

-40, and -50 series airplanes; Model DC–9–81

(MD–81), -82 (MD–82), -83 (MD–83), and -87

(MD–87) series airplanes; Model MD–88

airplanes; and C–9 (military) series airplanes;

as listed in McDonnell Douglas DC–9 Service

Bulletin 53–235, dated September 15, 1993;

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 (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 fatigue cracks in the skin and

longerons of the fuselage, which could result

in loss of the structural integrity of the

fuselage and, consequently, lead to rapid

depressurization of the airplane, accomplish

the following:

(a) Prior to the accumulation of 30,000 total

landings, or within 8,000 landings after the

effective date of this AD, whichever occurs

later, perform a high frequency eddy current

(HFEC) inspection of the external areas of the

fuselage to detect cracks of the skin and/or

longeron between stations Y=160.000 and

Y=218.000, in accordance with McDonnell

Douglas DC–9 Service Bulletin 53–235, dated

September 15, 1993.

(b) Condition 1 (No Cracks). If no crack is

detected during any inspection required by

this AD, accomplish either paragraph (b)(1)

or (b)(2) of this AD, in accordance with

McDonnell Douglas DC–9 Service Bulletin

53–235, dated September 15, 1993.

(1) Condition 1, Option I (Repetitive

Inspection). Repeat the HFEC inspection

required by paragraph (a) of this AD, and the

aided visual inspection specified in

paragraph 2.E. of the Accomplishment

Instructions of the service bulletin, at

intervals not to exceed 10,000 landings.

(2) Condition 1, Option II (Terminating

Action Modification). Accomplish the

preventative modification installation of

clips and doublers between stations

Y=160.000 and Y=218.000, in accordance

with the service bulletin. Accomplishment of

the modification constitutes terminating

action for the repetitive inspection

requirements of this AD.

(c) Condition 2 (Skin Cracks). If any skin

crack is detected during any inspection

required by this AD, prior to further flight,

repair it in accordance with McDonnell

Douglas DC–9 Service Bulletin 53–235, dated

September 15, 1993. After repair, accomplish

either paragraph (b)(1) or (b)(2) of this AD.

(d) Condition 3 (Longeron Cracks). If any

longeron crack is detected during any

inspection required by this AD, prior to

further flight, repair it in accordance with

McDonnell Douglas DC–9 Service Bulletin

53–235, dated September 15, 1993. After

repair, accomplish either paragraph (b)(1) or

(b)(2) of this AD.

(e) Prior to the accumulation of 100,000

total landings, or within 4 years after the

effective date of this AD, whichever occurs

later, accomplish the preventative

modification specified in paragraph 2.J. of

the Accomplishment Instructions of

McDonnell Douglas DC–9 Service Bulletin

53–235, dated September 15, 1993.

Accomplishment of the modification

constitutes terminating action for the

requirements of this AD.

(f) 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.

(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.

Issued in Renton, Washington, on February

28, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–5572 Filed 3–6–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF THE INTERIOR

Bureau of Indian Affairs

RIN 1076–AD14

25 CFR Part 290

Tribal Revenue Allocation Plans

AGENCY: Bureau of Indian Affairs,

Interior.

ACTION: Proposed Rule; Extension of

Comment Period; Correction.

SUMMARY: This notice corrects a

discrepancy in the notice published on

February 20, 1997, that extended the

comment period for the proposed rule.

The proposed rule would establish

procedures for submission, review, and

approval of tribal plans for distributing

revenues from gaming activities.

DATES: Comments must be received on

or before March 24, 1997.

ADDRESSES: Mail comments to George

Skibine, Director, Indian Gaming

Management Staff Office, Bureau of

Indian Affairs, 1849 C Street NW, MS

2070–MIB, Washington, DC 20240.