Federal Register / Vol. 65, No. 233 / Monday, December 4, 2000 / Rules and Regulations 75585

Note 6: There is no terminating action

currently available for the inspections

required by paragraph (c) of this AD.

Repetitive Inspections/Reinforcement/Repair

(No Cracks Detected)

(d) If no crack is detected during the

inspection required by paragraph (b) of this

AD, prior to further flight, oversize fastener

holes in accordance with Boeing Service

Bulletin 747–53A2417, Revision 1, dated July

23, 1998; or Boeing Alert Service Bulletin

747–53A2417, Revision 2, dated August 10,

2000; and accomplish the requirements of

paragraph (d)(1), (d)(2), or (d)(3) of this AD.

(1) Repeat the inspections specified in

paragraph (b) of this AD one time within

3,000 flight cycles. Within 3,000 flight cycles

after accomplishment of the repeat

inspection, accomplish paragraph (d)(2) or

(d)(3) of this AD.

(2) Reinforce the door frame, in accordance

with Figure 5 of the service bulletin.

Thereafter, at intervals not to exceed 3,000

flight cycles, perform a detailed visual

inspection to detect cracks of the forward and

aft side of the frame, in accordance with

Figure 6 of the service bulletin. Within

10,000 flight cycles after the reinforcement,

accomplish the requirements of paragraph

(d)(3) of this AD.

(3) Accomplish the web replacement repair

(‘‘Terminating Action’’) in accordance with

the service bulletin. Such repair constitutes

terminating action for the repetitive

inspection requirements of paragraphs (d)(1)

and (d)(2) of this AD.

Repair (Cracks Detected)

(e) If any crack is detected during any

inspection required by paragraph (b), (d)(1),

or (d)(2) of this AD, prior to further flight,

accomplish the repair (‘‘Terminating

Action’’) in accordance with Boeing Service

Bulletin 747–53A2417, Revision 1, dated July

23, 1998; or Boeing Alert Service Bulletin

747–53A2417, Revision 2, dated August 10,

2000. Such repair constitutes terminating

action for the repetitive inspection

requirements of paragraphs (d)(1) and (d)(2)

of this AD.

Repair

(f) If any cracking is detected during the

inspection required by paragraph (c) of this

AD, prior to further flight, repair in

accordance with a method approved by the

Manager, Seattle Aircraft Certification Office

(ACO), FAA; or in accordance with data

meeting the type certification basis of the

airplane approved by a Boeing Company

Designated Engineering Representative (DER)

who has been authorized by the Manager,

Seattle ACO, to make such findings. For a

repair method to be approved by the

Manager, Seattle ACO, as required by this

paragraph, the approval letter must

specifically reference this AD.

Alternative Methods of Compliance

(g) 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, Seattle

ACO. Operators shall submit their requests

through an appropriate FAA Principal

Maintenance Inspector, who may add

comments and then send it to the Manager,

Seattle ACO.

Note 7: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

Special Flight Permits

(h) 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.

Incorporation by Reference

(i) Except as provided in paragraph (f) of

this AD, the actions shall be done in

accordance with Boeing Service Bulletin

747–53A2417, Revision 1, dated July 23,

1998; or Boeing Alert Service Bulletin 747–

53A2417, Revision 2, dated August 10, 2000.

This incorporation by reference was

approved by the Director of the Federal

Register in accordance with 5 U.S.C. 552(a)

and 1 CFR part 51. Copies may be obtained

from Boeing Commercial Airplane Group,

P.O. Box 3707, Seattle, Washington 98124–

2207. Copies may be inspected at the FAA,

Transport Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington; or at the

Office of the Federal Register, 800 North

Capitol Street, NW., suite 700, Washington,

DC.

Effective Date

(j) This amendment becomes effective on

January 8, 2001.

Issued in Renton, Washington, on

November 22, 2000.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–30399 Filed 12–1–00; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–363–AD; Amendment

39–12013; AD 2000–24–06]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 707, 727C, and 727–100C Series

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 707,

727C, and 727–100C series airplanes,

that currently requires repetitive

inspections to detect cracking of the

main cargo door skin and frames, and

repair, if necessary. The existing AD

also provides optional terminating

modifications. This amendment requires

follow-on repetitive inspections of

repaired or modified areas for certain

airplanes. This amendment is prompted

by reports of cracking and/or tearing of

the main cargo door outer skin and

subsequent failure of the door frame.

The actions specified by this AD are

intended to detect and correct such

cracking and/or tearing, which could

result in failure of the door frame and

consequent rapid decompression of the

airplane.

DATES: Effective January 8, 2001.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 8,

2001.

ADDRESSES: The service information

referenced in this AD may be obtained

from Boeing Commercial Airplane

Group, P.O. Box 3707, Seattle,

Washington 98124–2207. This

information may be examined at the

Federal Aviation Administration (FAA),

Transport Airplane Directorate, Rules

Docket, 1601 Lind Avenue, SW.,

Renton, Washington; or at the Office of

the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Walt

Sippel, Aerospace Engineer, Airframe

Branch, ANM–120S, FAA, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2774;

fax (425) 227–1181.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39)

by superseding AD 83–02–09,

amendment 39–4549 (48 FR 6953,

February 17, 1983); which is applicable

to certain Boeing Model 707, 727C, and

727–100C airplanes; was published in

the Federal Register on April 19, 2000

(65 FR 20924). The action proposed to

continue to require repetitive

inspections to detect cracking of the

main cargo door skin and frames, and

repair, if necessary, and to continue to

provide for optional terminating

modifications. The action also proposed

to require new follow-on repetitive

inspections of repaired or modified

areas for certain airplanes.

Explanation of Change in the Final Rule

Paragraph (e)(2) of the proposed rule

states that it applies to airplanes on

which the modification specified in Part

II, Option 2 of the Accomplishment

Instructions of Boeing Service Bulletin

727–52A0079, Revision 4, dated June

19, 1981, Revision 5, dated June 17,

75586 Federal Register / Vol. 65, No. 233 / Monday, December 4, 2000 / Rules and Regulations

1983, or Revision 6, dated January 11,

1990, has been accomplished. However,

Part II, Option 2, and the modification

contained therein (which involves

installation of over-sized, protrudinghead rivets), appears only in Revision 6

of the service bulletin. Therefore,

paragraph (e)(2) of this final rule has

been revised to refer only to Revision 6

of the service bulletin. In addition,

paragraph (e)(1) of this final rule has

been revised to clarify that the

modification referred to as ‘‘Part II,

Option 1’’ in Revision 6 of the service

bulletin is referred to as ‘‘Part II’’ of

Revisions 4 and 5 of the service bulletin.

Comments

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

single comment received.

Request to Reference Terminating

Action

One commenter requests that the FAA

revise the proposed rule to terminate the

repetitive high frequency eddy current

(HFEC) inspections specified in

paragraph (e) of the proposed AD

following installation of over-sized,

protruding-head rivets in the skin of the

main cargo door. The commenter points

out that such installation of over-sized,

protruding-head rivets in crack-free

holes is one of two options for

modification in Revision 5 of the service

bulletin. The commenter states that

eliminating the requirement for HFEC

inspections would be consistent with

the requirements of AD 91–06–06,

amendment 39–6921 (56 FR 9612,

March 7, 1991), which does not require

repetitive HFEC inspections of the

upper row of fuselage lap splices once

protruding-head rivets have been

installed.

The FAA concurs with the intent of

the commenter’s request and its

rationale. However, the FAA infers that,

though the commenter refers to Revision

5 of the service bulletin, the correct

reference should be to Revision 6 of the

service bulletin. (As noted above,

Revision 5 does not describe the

modification to which the commenter

refers.) For airplanes modified per Part

II, Option 2 of the Accomplishment

Instructions of the service bulletin,

paragraph (e)(2) of the proposed rule

specifies repetitive internal and external

detailed visual and HFEC inspections of

the modified area. The FAA has

determined that the HFEC inspection is

no longer necessary following

accomplishment of the modification in

Part II, Option 2 of the Accomplishment

Instructions of Revision 6 of the service

bulletin. Therefore, paragraph (e)(2) of

this final rule has been revised to delete

reference to an HFEC inspection.

Conclusion

After careful review of the available

data, including the comment noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule with the changes

previously described. The FAA has

determined that these changes will

neither increase the economic burden

on any operator nor increase the scope

of the AD.

Cost Impact

There are approximately 50 Model

707 and 308 Model 727 series airplanes

of the affected design in the worldwide

fleet. The FAA estimates that 1 Model

707 and 81 Model 727 airplanes of U.S.

registry will be affected by this AD.

The cost impact information in AD

83–02–09 inadvertently contained

information relevant only to the X-ray

inspection; however, since the detailed

visual and eddy current inspections are

also acceptable methods to detect

cracking, this AD includes the estimated

number of work hours necessary to

accomplish any one of the three

inspection methods. Additionally, the

FAA has recently reviewed the figures

it has used over the past several years

in calculating the economic impact of

AD activity. In order to account for

various inflationary costs in the airline

industry, the FAA has determined that

it is necessary to increase the labor rate

used in these calculations from $40 per

work hour to $60 per work hour. The

cost impact information, below, has

been revised to reflect these changes.

Should an operator elect to

accomplish the detailed visual

inspection that is currently required by

AD 83–02–09, it will take approximately

1 work hour per airplane to accomplish,

at an average labor rate of $60 per work

hour. Based on these figures, the cost

impact of the detailed visual inspection

is estimated to be $60 per airplane.

Should an operator elect to

accomplish the eddy current inspection

that is currently required by AD 83–02–

09, it will take approximately 1 work

hour per airplane to accomplish, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of the eddy current inspection is

estimated to be $60 per airplane.

Should an operator elect to

accomplish the X-ray inspection that is

currently required by AD 83–02–09, it

will take approximately 3 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 X-ray inspection is estimated to

be $180 per airplane.

The detailed visual inspection (for

Model 727 series airplanes only)

required by this AD will take

approximately 1 work hour per airplane

to accomplish, at an average labor rate

of $60 per work hour. Based on these

figures, the cost impact of the detailed

visual inspection is estimated to be

$4,860, or $60 per airplane.

The eddy current inspection (for

Model 727 series airplanes only)

required by this AD will take

approximately 1 work hour per airplane

to accomplish, at an average labor rate

of $60 per work hour. Based on these

figures, the cost impact of the eddy

current inspection is estimated to be

$4,860, or $60 per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the requirements of this AD action, and

that no operator would accomplish

those actions in the future if this AD

were not adopted. The cost impact

figures discussed in AD rulemaking

actions represent only the time

necessary to perform the specific actions

actually required by the AD. These

figures typically do not include

incidental costs, such as the time

required to gain access and close up,

planning time, or time necessitated by

other administrative actions.

Regulatory Impact

The regulations adopted herein will

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 final rule does not

have federalism implications under

Executive Order 13132.

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)

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 final evaluation has

been prepared for this action and it is

contained in the Rules Docket. A copy

of it may be obtained from the Rules

Docket at the location provided under

the caption ADDRESSES.

Federal Register / Vol. 65, No. 233 / Monday, December 4, 2000 / Rules and Regulations 75587

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Incorporation by reference,

Safety.

Adoption of the Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration amends 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 39–4549 (48 FR

6953, February 17, 1983), and by adding

a new airworthiness directive (AD),

amendment 39–12013, to read as

follows:

2000–24–06 Boeing: Amendment 39–12013.

Docket 99–NM–363–AD. Supersedes AD

83–02–09, Amendment 39–4549.

Applicability: Model 707, 727C, and 727–

100C series airplanes; as listed in Boeing

Service Bulletins 2999, Revision 3, dated

January 12, 1972, and 727–52–79, Revision 4,

dated June 19, 1981; 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 (g)(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 correct cracking of the main

cargo door skin and frames, which could

result in failure of the door frame, and

consequent rapid decompression of the

airplane, accomplish the following:

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 such as mirror,

magnifying lenses, etc., may be used. Surface

cleaning and elaborate access procedures

may be required.’’

Restatement of Requirements of AD 83–02–

09:

Initial Inspection

(a) Within 500 landings after March 3, 1983

(the effective date of AD 83–02–09,

amendment 39–4549), or prior to the

accumulation of 25,000 total landings after

March 3, 1983, whichever occurs later:

Perform an inspection (detailed visual, eddy

current, or X-ray) to detect cracks of the main

cargo door outer skin and frames between

body stations (BS) 505 and 595, from the

lower edge of the door hinge a minimum of

6 inches down, and 6 inches above, and 3

inches below the center line of stringer 10,

in accordance with Boeing Service Bulletin

2999, Revision 3, dated January 12, 1972, or

Revision 4, dated January 31, 1991 (for Model

707 series airplanes); or Boeing Service

Bulletin 727–52–79, Revision 4, dated June

19, 1981, or Boeing Service Bulletin 727–52–

79, Revision 5, dated June 17, 1983, or

Boeing Service Bulletin 727–52A0079,

Revision 6, dated January 11, 1990 (for Model

727 series airplanes); as applicable.

Repetitive Inspections

(b) Repeat the inspection required by

paragraph (a) of this AD at the times

specified in paragraph (b)(1), (b)(2) or (b)(3)

of this AD; as applicable; until

accomplishment of the modification required

by paragraph (d) of this AD.

(1) Repeat the detailed visual inspection at

intervals not to exceed 500 landings.

(2) Repeat the eddy current inspection at

intervals not to exceed 750 landings.

(3) Repeat the X-ray inspection at intervals

not to exceed 1,000 landings.

Repair

(c) If any cracking is detected during any

inspection required by paragraph (a) or (b) of

this AD: Prior to further flight, repair any

cracks detected in accordance with Boeing

Service Bulletin 2999, Revision 3, dated

January 12, 1972, or Revision 4, dated

January 31, 1991 (for Model 707 series

airplanes); or Boeing Service Bulletin 727–

52–79, Revision 4, dated June 19, 1981, or

Boeing Service Bulletin 727–52–79, Revision

5, dated June 17, 1983, or Boeing Service

Bulletin 727–52A0079, Revision 6, dated

January 11, 1990 (for Model 727 series

airplanes); as applicable.

Optional Terminating Action

(d) Modification of the main cargo door in

accordance with Part II, Option 1 or Option

2, as applicable, of the Accomplishment

Instructions of Boeing Service Bulletin 2999,

Revision 3, dated January 12, 1972, or

Revision 4, dated January 31, 1991 (for Model

707 series airplanes); or Boeing Service

Bulletin 727–52–79, Revision 4, dated June

19, 1981, or Boeing Service Bulletin 727–52–

79, Revision 5, dated June 17, 1983, or

Boeing Service Bulletin 727–52A0079,

Revision 6, dated January 11, 1990 (for Model

727 series airplanes); as applicable;

constitutes terminating action for the

requirements of paragraphs (a) and (b) of this

AD.

New Requirements of this AD:

Post-Repair/Post-Mod Repetitive Inspections

(e) For Model 727 series airplanes: Within

27,000 flight cycles after accomplishment of

the repair specified in paragraph (c) of this

AD, and/or the modification specified in

paragraph (d) of this AD, as applicable; or

within 1,000 flight cycles after the effective

date of this AD; whichever occurs later;

accomplish the requirements of paragraph

(e)(1) or (e)(2) of this AD, as applicable.

(1) For airplanes that have accomplished

the modification specified in Part II of the

Accomplishment Instructions of Boeing

Service Bulletin 727–52–79, Revision 4,

dated June 19, 1981, or Revision 5, dated

June 17, 1983; or in Part II, Option 1, of the

Accomplishment Instructions of Boeing

Service Bulletin 727–52A0079, Revision 6,

dated January 11, 1990: Perform a detailed

visual and eddy current inspection of the

modified area and/or any repaired area to

detect cracks, in accordance with the service

bulletin. Repeat the inspections at intervals

not to exceed 3,800 flight cycles.

(2) For airplanes that have accomplished

the modification specified in Part II, Option

2 of the Accomplishment Instructions of

Boeing Service Bulletin 727–52A0079,

Revision 6, dated January 11, 1990: Perform

an internal and external detailed visual

inspection of the modified area to detect

cracks in accordance with the service

bulletin. Repeat the inspection at intervals

not to exceed 3,800 flight cycles.

Repair

(f) If any cracking is detected during any

inspection required by paragraph (e)(1) or

(e)(2) of this AD: Prior to further flight, repair

any cracks detected in accordance with a

method approved by the Manager, Seattle

Aircraft Certification Office (ACO), FAA; or

in accordance with data meeting the type

certification basis of the airplane approved

by a Boeing Company Designated

Engineering Representative who has been

authorized by the Manager, Seattle ACO, to

make such findings. For a repair method to

be approved by the Manager, Seattle ACO, as

required by this paragraph, the Manager’s

approval letter must specifically reference

this AD.

Alternative Methods of Compliance

(g)(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, Seattle

ACO. Operators shall submit their requests

through an appropriate FAA Principal

Maintenance Inspector, who may add

comments and then send it to the Manager,

Seattle ACO.

(2) Alternative methods of compliance

approved previously in accordance with AD

83–02–09, amendment 39–4549, are

approved as alternative methods of

compliance with this AD.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

Note 4: Incorporation of the Boeing Model

707–720 Supplemental Structural Inspection

75588 Federal Register / Vol. 65, No. 233 / Monday, December 4, 2000 / Rules and Regulations

Document (SSID) into the operator’s

approved airplane maintenance program

constitutes an approved alternative method

of compliance for Model 707 and 720 series

airplanes.

Special Flight Permits

(h) 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.

Incorporation by Reference

(i) Except as provided by paragraph (f) of

this AD, the actions shall be done in

accordance with Boeing Service Bulletin

2999, Revision 3, dated January 12, 1972;

Boeing Service Bulletin 2999, Revision 4,

dated January 31, 1991; Boeing Service

Bulletin 727–52–79, Revision 4, dated June

19, 1981; Boeing Service Bulletin 727–52–79,

Revision 5, dated June 17, 1983; or Boeing

Service Bulletin 727–52A0079, Revision 6,

including Addendum, dated January 11,

1990; as applicable. This incorporation by

reference was approved by the Director of the

in accordance with 5 U.S.C. 552(a) and 1 CFR

part 51. Copies may be obtained from Boeing

Commercial Airplane Group, P.O. Box 3707,

Seattle, Washington 98124–2207. Copies may

be inspected at the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW., Renton,

Washington; or at the Office of the Federal

Register, 800 North Capitol Street, NW., suite

700, Washington, DC.

Effective Date

(j) This amendment becomes effective on

January 8, 2001.

Issued in Renton, Washington, on

November 22, 2000.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–30398 Filed 12–1–00; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–378–AD; Amendment

39–12027; AD 2000–24–20]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 707 and 720 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to all Boeing Model 707 and

720 series airplanes, that requires

repetitive inspections of certain

stringers and around certain fastener

holes of the lower skin of the wings to

detect fatigue cracking, and repair, if

necessary. This action is necessary to

detect and correct such cracking and

consequent damage to adjacent

structure, which could result in reduced

structural integrity of the airplane. This

action is intended to address the

identified unsafe condition.

DATES: Effective January 8, 2001.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 8,

2001.

ADDRESSES: The service information

referenced in this AD may be obtained

from Boeing Commercial Airplane

Group, P.O. Box 3707, Seattle,

Washington 98124–2207. This

information may be examined at the

Federal Aviation Administration (FAA),

Transport Airplane Directorate, Rules

Docket, 1601 Lind Avenue, SW.,

Renton, Washington; or at the Office of

the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

James Rehrl, Aerospace Engineer,

Airframe Branch, ANM–120S, FAA,

Seattle Aircraft Certification Office,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(425) 227–2783; fax (425) 227–1181.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an airworthiness directive (AD)

that is applicable to all Boeing Model

707 and 720 series airplanes was

published in the Federal Register on

August 10, 2000 (65 FR 48941). That

action proposed to require repetitive

inspections of certain stringers and

around certain fastener holes of the

lower skin of the wings to detect fatigue

cracking, and repair, if necessary.

Comment Received

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

single comment received.

The commenter, Boeing, requests that

all references to Model 720 series

airplanes be deleted from the proposed

rule. Specifically, Boeing suggests that:

• the Cost Impact paragraph be

revised to specify that there are

approximately ‘‘* * * 49 affected

Model 707 series airplanes worldwide

* * *;’’

• paragraph (a) of the proposed rule

be removed; and

• Note 2 of the proposed rule be

revised to state that the actions required

by AD 81–11–06 R1, amendment 39–

4178, for Model 720 airplanes remain in

effect. The commenter states that there

are no Model 720 series airplanes in

active service. In addition, the changes

in Revision 4 of the referenced alert

service bulletin affect only Model 707

series airplanes.

The FAA does not concur with the

commenter’s request to remove

references to Model 720 series airplanes

from this final rule. Even though no

Model 720 series airplanes are currently

in active service, including this model

in the applicability of the final rule is

necessary to ensure that the unsafe

condition is addressed on any Model

720 series airplane that is returned to

service in the future. In addition, the

FAA notes that several changes in

Revision 4 of the alert service bulletin

do, in fact, address Model 720 series

airplanes. No change to this final rule is

necessary.

Conclusion

After careful review of the available

data, including the comment noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule as proposed.

Cost Impact

There are approximately 49 Model

707 and 720 series airplanes of the

affected design in the worldwide fleet.

The FAA estimates that 2 airplanes of

U.S. registry will be affected by this AD,

that it will take approximately 56 work

hours per airplane to accomplish the

required actions, and that the average

labor rate is $60 per work hour. Based

on these figures, the cost impact of the

AD on U.S. operators is estimated to be

$6,720, or $3,360 per airplane, per

inspection cycle.

The cost impact figure discussed

above is based on assumptions that no

operator has yet accomplished any of

the requirements of this AD action, and

that no operator would accomplish

those actions in the future if this AD

were not adopted. The cost impact

figures discussed in AD rulemaking

actions represent only the time

necessary to perform the specific actions

actually required by the AD. These

figures typically do not include

incidental costs, such as the time

required to gain access and close up,

planning time, or time necessitated by

other administrative actions.

Regulatory Impact

The regulations adopted herein will

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