10356 Federal Register / Vol. 66, No. 32 / Thursday, February 15, 2001 / Rules and Regulations

Bell Helicopter Textron, Inc. (BHTI)

Model 204B helicopters that requires

replacing any main rotor mast assembly

(mast), part number (P/N) 204–011–

450–001, within 25 hours time-inservice (TIS). This amendment is

prompted by the crash of a restricted

category Model UH–1B helicopter due

to failure of a mast, P/N 204–011–450–

001. The same mast P/N is used on the

Model 204B helicopters. The actions

specified by this AD are intended to

prevent failure of the mast and

subsequent loss of control of the

helicopter.

EFFECTIVE DATE: March 22, 2001.

FOR FURTHER INFORMATION CONTACT:

Michael Kohner, Aviation Safety

Engineer, FAA, Rotorcraft Directorate,

Rotorcraft Certification Office, Fort

Worth, Texas 76193–0170, telephone

(817) 222–5447, fax (817) 222–5783.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an AD for BHTI Model 204B

helicopters was published in the

Federal Register on October 2, 2000 (65

FR 58681). That action proposed

replacing any mast, P/N 204–011–450–

001, within 25 hours TIS.

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. No

comments were received on the

proposal or the FAA’s determination of

the cost to the public. The FAA has

determined that air safety and the

public interest require the adoption of

the rule as proposed.

The FAA estimates that 15 helicopters

of U.S. registry will be affected by this

AD, that it will take approximately 10

work hours per helicopter to accomplish

the required actions, and that the

average labor rate is $60 per work hour.

Required parts will cost approximately

$8,862 per helicopter. Based on these

figures, the total cost impact of the AD

on U.S. operators is estimated to be

$141,930.

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 FAA, Office of the

Regional Counsel, Southwest Region,

2601 Meacham Blvd., Room 663, Fort

Worth, Texas.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, 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

adding a new airworthiness directive to

read as follows:

2001–02–11 Bell Helicopter Textron, Inc.:

Amendment 39–12096. Docket No. 2000-

SW–16-AD.

Applicability: Model 204B helicopters with

main rotor mast assembly, part number (P/N)

204–011–450–001, installed, certificated in

any category.

Note 1: This AD applies to each helicopter

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 helicopters 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 (b) 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 25 hours

time-in-service, unless accomplished

previously.

To prevent failure of the main rotor mast

assembly (mast) and subsequent loss of

control of the helicopter, accomplish the

following:

(a) Remove any mast, P/N 204–011–450–

001, from service and replace it with an

airworthy mast. Accomplishing the

requirement of this paragraph constitutes

terminating action for the requirements of

this AD. P/N 204–011–450–001 is not eligible

for installation on any helicopter.

(b) 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, Rotorcraft

Certification Office, Rotorcraft Directorate,

FAA. Operators shall submit their requests

through an FAA Principal Maintenance

Inspector, who may concur or comment and

then send it to the Manager, Rotorcraft

Certification Office.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Rotorcraft Certification

Office.

(c) 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 helicopter

to a location where the requirements of this

AD can be accomplished.

(d) This amendment becomes effective on

March 22, 2001.

Issued in Fort Worth, Texas, on January 19,

2001.

Henry A. Armstrong,

Manager, Rotorcraft Directorate, Aircraft

Certification Service.

[FR Doc. 01–3670 Filed 2–14–01; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–368–AD; Amendment

39–12110; AD 2001–03–06]

RIN 2120–AA64

Airworthiness Directives; Raytheon

(Beech) Model MU–300, MU–300–10,

400, and 400A Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to Raytheon (Beech) Model

MU–300, MU–300–10, 400, and 400A

series airplanes, that requires repetitive

inspections of the bleed air supply tube

assemblies for discrepancies; and

replacement of the bleed air tube

assembly with a new bleed air tube

assembly, if necessary. In lieu of

accomplishing the repetitive

Federal Register / Vol. 66, No. 32 / Thursday, February 15, 2001 / Rules and Regulations 10357

inspections, this AD also provides for a

revision of the Airworthiness

Limitations to incorporate, among other

things, certain inspections and

compliance times to detect

discrepancies of the subject area; and

corrective action, if necessary. This

amendment is prompted by reports of

broken wire braiding in the bellows

assembly of the bleed air supply tube

assembly due to premature failure from

loading. The actions specified by this

AD are intended to prevent the bleed air

supply tube assembly from

disconnecting and contacting other

pneumatic or electrical systems of the

airplane or expelling high temperature

air on surrounding systems and

structure. Such a condition could

reduce the functional capabilities of the

airplane or the ability of the flight crew

to cope with adverse operating

conditions.

DATES: Effective March 22, 2001.

ADDRESSES: The service information

referenced in this AD may be obtained

from Raytheon Aircraft Company,

Manager, Service Engineering, Beechjet

Premier Technical Support, P.O. Box 85,

Wichita, Kansas 67201–0085. 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 FAA,

Wichita Aircraft Certification Office,

1801 Airport Road, Room 100, MidContinent Airport, Wichita, Kansas.

FOR FURTHER INFORMATION CONTACT: Paul

C. DeVore, Aerospace Engineer, Systems

and Propulsion Branch, ACE–116W,

FAA, Wichita Aircraft Certification

Office, 1801 Airport Road, Room 100,

Mid-Continent Airport, Wichita, Kansas,

67209; telephone (316) 946–4142; fax

(316) 946–4407.

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 Raytheon

(Beech) Model MU–300, MU–300–10,

400, and 400A series airplanes was

published in the Federal Register on

May 10, 2000 (65 FR 30031). That action

proposed to require repetitive

inspections of the bleed air supply tube

assemblies for discrepancies; and

replacement of the bleed air tube

assembly with a new bleed air tube

assembly, if necessary. That action also

proposed to require that, in lieu of

accomplishing the repetitive

inspections, the Airworthiness

Limitations Section (ALS) be revised to

specify, among other things, certain

inspections to detect discrepancies and

compliance times for the subject area;

and corrective action, if necessary.

Since the Issuance of the NPRM

The FAA has reviewed and approved

Raytheon Aircraft Beechjet 400/400A

Maintenance Manual, Airworthiness

Limitations, Page 1, Section 4–00–00,

Revision B26, dated August 27, 1999.

The FAA also has reviewed and

approved Raytheon Aircraft Beechjet

400/400A Maintenance Manual, TimeLimited Inspections, Pages 3 and 6,

Section 4–00–02, and Pages 4 and 9,

Section 4–00–04, Revision B26, dated

August 27, 1999. The FAA has

determined that Revision B26 contains

no information that has been revised or

added to since the issuance of Revision

B23 regarding STARS Code 361031

(Bleed Air System). Since Revision B26

is the most current ALS revision, the

FAA has cited Revision B26 in this final

rule, as no required work has been

added or changed from the requirements

set forth in the proposed rule.

The FAA has reviewed and approved

Raytheon Aircraft Diamond 1/1A MU–

300 Maintenance Requirement Manual,

Revision 9, dated February 26, 1999.

The FAA has determined that Revision

9 contains no information that has been

revised or added to since the issuance

of Revision 8 regarding the Bleed Air

System. Since Revision 9 is the most

current ALS revision, the FAA has cited

Revision 9 in this final rule, as no

required work has been added or

changed from the requirements set forth

in the proposed rule.

Clarification of Paragraph (a) of the

Final Rule

The FAA notes that the method of

compliance in paragraph (a) of the

proposal was inadvertently not included

in the proposal. Therefore, the FAA has

specified that those actions required by

paragraph (a)(1) of this AD must be

accomplished in accordance with the

Airplane Maintainance Manual, Chapter

4, dated August 27, 1999. Paragraph

(a)(1) of the final rule has been revised

accordingly.

Comments to the NPRM

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

comments received.

Request to Clarify the Compliance Time

One commenter requests that the

compliance time specified in paragraph

(b) of the proposal be clarified to state

that the actions must be accomplished

within 200 hours time-in-service.

The FAA concurs with the commenter

that clarification is needed. Since

paragraph (a) of the proposal clearly

specifies a compliance time of 200

hours time-in-service, paragraph (b) of

the the proposal has been redesignated

as paragraph (a)(2) to clarify that the 200

hours time-in-service also applies to

those requirements.

Request to Specify Incorporation of

Airworthiness Limitations Section as

Terminating Action

One commenter requests that the

proposal clearly specify that

incorporation of the revisions of the

ALS specified in the proposal be

designated as a terminating action

‘‘until such time as the operator elects

to inspect the affected aircraft in

accordance with paragraphs (a) or (d).’’

The FAA does not concur.

Accomplishment of the requirements of

paragraph (a)(2) of this AD

(incorporation of the ALS revisions) is

simply considered to be one way of

complying with the requirements of

paragraph (a) of this AD. Incorporation

of the ALS revisions relieves the

operator from continually updating

compliance with the inspection

requirements of this AD, but does not

‘‘terminate’’ the requirement to perform

the inspections that are now enforceable

as part of the ALS. No change is

necessary to the final rule.

Request to Clarify the Requirements of

Paragraph (b)

The same commenter also requests

that the proposal clarify that the ALS

does not require any inspection until

the aircraft accumulates 1,000 hours

time-in-service. The commenter further

requests that the proposal clearly

reference the current 20-hour

‘‘inspection interval tolerance’’

provided for in the ALS.

The FAA acknowledges that the ALS

does not require an inspection until the

aircraft accumulates 1,000 hours timein-service, and that the ALS provides for

a 20-hour ‘‘inspection interval

tolerance.’’ However, the requirements

of paragraph (a)(2) of this AD merely

require incorporating procedures

specified in certain revisions of the ALS

of the Instructions of Continued

Airworthiness. The FAA does not

consider it necessary to identify each of

the procedures, provisions, or

requirements that are included in those

specific revisions of the ALS. Therefore,

no change has been made to the final

rule in this regard.

Conclusion

After careful review of the available

data, including the comments noted

10358 Federal Register / Vol. 66, No. 32 / Thursday, February 15, 2001 / Rules and Regulations

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 530

airplanes of the affected design in the

worldwide fleet. The FAA estimates that

452 airplanes of U.S. registry will be

affected by this AD, that it will take

approximately 1 work hour per airplane

to accomplish either the inspection or

the revision to the Airworthiness

Limitations Section, 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 $27,120, or $60 per airplane.

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.

Should an operator elect to

accomplish the optional terminating

action that would be provided by this

AD action, it would take approximately

1 work hour to accomplish it, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of the optional terminating action would

be $60 per airplane.

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.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, 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

adding the following new airworthiness

directive:

2001–03–06 Raytheon Aircraft Company

(Formerly Beech): Amendment 39–

12110. Docket 98–NM–368–AD.

Applicability: All Model MU–300, MU–

300–10, 400, and 400A series airplanes,

certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

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 (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 as indicated, unless

accomplished previously.

To prevent the bleed air supply tube

assembly from disconnecting and contacting

other pneumatic or electrical systems of the

airplane or expelling high temperature air on

surrounding systems and structure, which

could result in reduced functional

capabilities of the airplane or the ability of

the flight crew to cope with adverse

operating conditions; accomplish the

following:

Inspection

(a) Within 200 hours time-in-service after

the effective date of this AD, accomplish the

actions specified in either paragraph (a)(1) or

(a)(2) of this AD.

(1) Perform a general visual inspection of

the bleed air supply tube assemblies for

broken wire braiding on the bellows

assemblies or for ruptured or leaking bellow

assemblies. The bleed air supply tube

assemblies are located within the aft fuselage

and connect to mating ducting in the pylon

area on the right and left side of the airplane.

Repeat the inspection thereafter at intervals

not to exceed 400 hours time-in-service. If

any broken wire is detected or if any bellow

assembly is ruptured or leaking, prior to

further flight, replace the bleed air tube

assembly with a new bleed air tube assembly,

in accordance with the Airplane

Maintenance Manual, Revision B26 of

Chapter 4, dated August 27, 1999.

Note 2: For the purposes of this AD, a

general visual inspection is defined as ‘‘A

visual examination of an interior or exterior

area, installation, or assembly to detect

obvious damage, failure, or irregularity. This

level of inspection is made under normally

available lighting conditions such as

daylight, hangar lighting, flashlight, or droplight, and may require removal or opening of

access panels or doors. Stands, ladders, or

platforms may be required to gain proximity

to the area being checked.’’

(2) Revise the Airworthiness Limitations

Sections of the Instructions for Continued

Airworthiness by incorporating the

procedures specified in Chapter 4,

‘‘Airworthiness Limitations’’ of Raytheon

Aircraft Beechjet 400/400A Maintenance

Manual, Revision B26, dated August 27,

1999, for Model MU–300–10, 400, and 400A

series airplanes; or Section MR–11–00,

‘‘Airworthiness Limitations’’ of Raytheon

Aircraft Diamond 1/1A MU–300

Maintenance Requirement Manual, Revision

9, dated February 26, 1999 (for Model MU–

300 airplanes); as applicable.

(b) Except as provided in paragraph (c) of

this AD: After the action specified in

paragraph (a)(2) of this AD has been

accomplished, no alternative inspections or

inspection intervals may be approved for the

part specified in paragraph (a)(2) of this AD.

Alternative Methods of Compliance

(c) 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, Wichita

Aircraft Certification Office (ACO), FAA.

Operators shall submit their requests through

an appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Wichita ACO.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Wichita ACO.

Special Flight Permits

(d) 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.

Effective Date

(e) This amendment becomes effective on

March 22, 2001.

Federal Register / Vol. 66, No. 32 / Thursday, February 15, 2001 / Rules and Regulations 10359

Issued in Renton, Washington, on February

7, 2001.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 01–3672 Filed 2–14–01; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NM–279–AD; Amendment

39–12117; AD 2001–03–13]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 707 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to certain Boeing Model 707

series airplanes, that requires

modification of certain areas of the

upper skin of the wing. This

amendment is necessary to prevent

cracking of the upper skin of the wing,

which could result in reduced structural

integrity of the wing. This action is

intended to address the identified

unsafe condition.

DATES: Effective March 22, 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.

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 certain Boeing

Model 707 series airplanes was

published in the Federal Register on

November 28, 2000 (65 FR 70819). That

action proposed to require modification

of certain areas of the upper skin of the

wing.

Comments

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. No

comments were submitted in response

to the proposal or the FAA’s

determination of the cost to the public.

Conclusion

The FAA has determined that air

safety and the public interest require the

adoption of the rule as proposed.

Cost Impact

There are approximately 5 airplanes

of the affected design in the worldwide

fleet. The FAA estimates that 1 airplane

of U.S. registry will be affected by this

AD, that it will take approximately 8

work hours 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 the

single U.S. operator is estimated to be

$480.

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

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.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, 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

adding the following new airworthiness

directive:

2001–03–13 Boeing: Amendment 39–12117.

Docket 2000–NM–279–AD.

Applicability: Model 707 series airplanes;

as listed in Boeing Service Bulletin 2378,

Revision 1, dated June 30, 1967; 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 (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 as indicated, unless

accomplished previously.

To prevent cracking of the upper skin of

the wing, which could result in reduced

structural integrity of the wing, accomplish

the following:

Modification

(a) Prior to the accumulation of 20,000 total

flight hours, or within 24 months after the

effective date of this AD, whichever occurs

later, modify the upper skin of the wing at

wing stringers 10A and 11A on both the leftand right-hand wings of the airplane, in

accordance with Boeing Service Bulletin

2378, Revision 1, dated June 30, 1967.

(b) During the high frequency eddy current

inspection included as part of the

modification required by paragraph (a) of this

AD, if any crack is found, prior to further

flight, repair in accordance with the

applicable section of the Boeing 707

Structural Repair Manual.