31124 Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations

(b) The tufts are used for performing the

physical check to determine that the upper

wing is free of ice by observing that the tufts

move freely.

Up to eight (8) decals and/or tufts may be

missing, provided:

(a) Takeoff may not be initiated unless the

flight crew verifies that a physical (hands-on)

check is made of the upper wing in the

location of the missing decals and/or tufts to

assure that there is no ice on the wing when

icing conditions exist;

OR

(b) When the ambient temperature is more

than 50 degrees F.’’

(3) Install inspection aids (i.e., tufts, decals,

mount pads, painted symbols, and paint

stripes) on the inboard side of the wings’

upper surfaces, in accordance with

McDonnell Douglas Service Bulletin 30–59,

dated September 18, 1989; Revision 1, dated

January 5, 1990; or Revision 2, dated August

15, 1990.

Alternative Methods of Compliance

(i)(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, Los

Angeles 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, Los Angeles ACO.

(2) The following alternative methods of

compliance (AMOC) were approved

previously per AD 92–03–02, amendment

39–8156, and are approved as AMOC’s with

the indicated paragraphs of this AD:

(i) Installation of a non-skid, striped

triangular symbol per Option 5 of McDonnell

Douglas Service bulletin MD80–30–059,

Revision 4 though Revision 7, is approved as

an AMOC with paragraph (b) of this AD.

(ii) Revision of the Configuration Deviation

List (CDL) Appendix of the AFM by inserting

a copy of CDL Appendix, Section I, Page 2A,

dated March 10, 1993, into the AFM, is

approved as an AMOC with paragraph (c) of

this AD.

Note 8: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

Special Flight Permits

(j) 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.

Incorporation by Reference

(k) The actions required by paragraphs (c),

(d), (e), (f)(1), and (h)(3) of this AD shall be

done in accordance with the applicable

service document identified in Table 1 of this

AD.

TABLE 1.—REFERENCED SERVICE

DOCUMENTS

Service document Revision

level Date

McDonnell Douglas

Service Bulletin

30–59.

Original ... Sept. 18,

1989.

McDonnell Douglas

Service Bulletin

30–59.

1 ............. Jan. 5,

1990.

McDonnell Douglas

Service Bulletin

30–59.

2 ............. Aug. 15,

1990.

McDonnell Douglas

Alert Service Bulletin MD80–

30A087.

Original ... Sept. 22,

1997.

McDonnell Douglas

Service Bulletin

MD80–30–090.

Original ... Oct. 19,

1999.

McDonnell Douglas

Service Bulletin

MD80–30–078.

01 ........... Apr. 8,

1997.

McDonnell Douglas

Service Bulletin

MD80–30–071.

02 ........... Feb. 6,

1996

(1) The incorporation by reference of

McDonnell Douglas Service Bulletin 30–59,

dated September 18, 1989; McDonnell

Douglas Service Bulletin 30–59, Revision 1,

dated January 5, 1990; and McDonnell

Douglas Service Bulletin 30–59, Revision 2,

dated August 15, 1990; was approved

previously by the Director of the Federal

Register as of January 17, 1992 (57 FR 2014,

January 17, 1992).

(2) The incorporation by reference of the

remaining service bulletins listed in Table 1

of this AD, was approved previously by the

Director of the Federal Register as of May 7,

2001 (66 FR 17499, April 2, 2001).

(3) Copies may be obtained from Boeing

Commercial Aircraft Group, Long Beach

Division, 3855 Lakewood Boulevard, Long

Beach, California 90846, Attention: Data and

Service Management, Dept. C1–L5A (D800–

0024). Copies may be inspected at the FAA,

Transport Airplane Directorate, 1601 Lind

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

FAA, Los Angeles Aircraft Certification

Office, 3960 Paramount Boulevard,

Lakewood, California; or at the Office of the

Federal Register, 800 North Capitol Street,

NW., suite 700, Washington, DC.

Effective Date

(1) The effective date of this amendment

remains May 7, 2001.

Issued in Renton, Washington, on May 30,

2001.

Vi L. Lipski,

Manager, Transport Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 01–14040 Filed 6–8–01; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–283–AD; Amendment

39–12248; AD 2001–11–06]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 747 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 747–

100 series airplanes, that currently

requires repetitive inspections to detect

cracking of the outer chord of the body

station (BS) 1480 upper and lower

bulkhead and longeron splice fitting;

repair, if necessary; and modification of

the skin splice plate, the outer chord

splice fitting, and the stringer interface

of the lower bulkhead, if necessary. This

amendment revises the applicability of

the existing AD to add additional

airplanes, requires accomplishment of

previously optional inspections and

clarifies those inspections, extends

certain compliance times, and requires

additional work in certain areas. This

amendment is prompted by reports that

fatigue cracking has been found in the

outer chord of the BS 1480 bulkhead at

the overwing longeron splice on

airplanes not subject to the existing AD.

The actions specified by this AD are

intended to detect and correct fatigue

cracking of the skin, splice fittings,

bulkhead web, and outer chord of the

BS 1480 upper and lower bulkhead and

longeron splice fitting, which could

result in reduced structural integrity of

the fuselage and the inability to carry

limit load.

DATES: Effective July 16, 2001.

The incorporation by reference of

Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including

Appendices A, B, C, and D; dated July

6, 2000; as listed in the regulations, is

approved by the Director of the Federal

Register as of July 16, 2001.

The incorporation by reference of

Boeing Alert Service Bulletin 747–

53A2390, dated July 31, 1997, as listed

in the regulations, was approved

previously by the Director of the Federal

Register as of October 7, 1998 (63 FR

50508, September 22, 1998).

ADDRESSES: The service information

referenced in this AD may be obtained

from Boeing Commercial Airplane

Group, P.O. Box 3707, Seattle,

Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations 31125

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: Rick

Kawaguchi, Aerospace Engineer,

Airframe Branch, ANM–120S, FAA,

Seattle Aircraft Certification Office,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(425) 227–1153; fax (425) 227–1181.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39)

by superseding AD 98–20–25,

amendment 39–10791 (63 FR 50508,

September 22, 1998), which is

applicable to certain Boeing Model 747–

100 series airplanes, was published in

the Federal Register on November 9,

2000 (65 FR 67311). The action

proposed to revise the applicability of

the existing AD to add additional

airplanes, require accomplishment of

previously optional inspections and

clarify those inspections, extend certain

compliance times, and require

additional work in certain areas.

Comments

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

comments received.

Revise Statement of Unsafe Condition

One commenter requests that the FAA

revise the statement of unsafe condition

in various places in the proposed AD.

The statement appears as follows in the

proposal: ‘‘The actions specified in this

proposed AD are intended to detect and

correct fatigue cracking of the outer

chord * * *.’’ The commenter states

that cracking has also been found in the

skin, splice fittings, and bulkhead web,

in addition to the outer chord. The FAA

concurs with the commenter’s request,

and has changed this statement

accordingly in various locations in this

final rule.

Give Credit for Revision 1 of Service

Bulletin

One commenter requests that the FAA

revise the proposed rule to refer to

Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including

Appendices A, B, C, and D; dated July

6, 2000; in addition to the original issue

of the service bulletin; as an acceptable

source of service information for

paragraph (a)(2). As justification for its

request, the commenter states that

operators of Boeing Model 747–400

series airplanes may not have the

original issue of the service bulletin

available. The commenter also asks the

FAA to revise Note 2 of the proposed

AD to refer to Revision 1.

The FAA concurs with the intent of

the commenter’s request, but not with

its justification because paragraph (a)(2)

of this AD does not apply to Model 747–

400 series airplanes. The FAA

acknowledges, however, that Boeing

Alert Service Bulletin 747–53A2390,

Revision 1, has previously been

approved as an alternative method of

compliance for the actions in

paragraphs (a)(1) and (a)(2) of this AD.

To clarify this, the FAA has revised this

final rule to add Note 2 after paragraph

(a) of this AD, which states that

Revision 1 has been approved as an

alternative method of compliance for

paragraphs (a)(1) and (a)(2) of this AD.

(Subsequent notes have been

renumbered accordingly.) Also, the FAA

has revised Note 3 of this final rule

(which was Note 2 of the proposed rule)

to refer to Revision 1 as well as the

original issue of the service bulletin.

Revise Various Paragraphs for

Clarification

One commenter requests that, for

clarity, the FAA make the following

changes to the proposed rule, for the

following reasons:

• Revise the phrase ‘‘in accordance

with the flight safety inspection

program’’ to ‘‘in accordance with the

after[-]modification inspection

program’’ in paragraphs (d)(2), (e)(2),

and (g)(2), because the inspections

following the Plan ‘‘B’’ modification

should not be confused with the flight

safety inspections for Plan ‘‘A.’’

• Revise the reference to Figures 6

and 7 in paragraph (e)(1) of the

proposed rule to refer to only Figure 6,

because Figure 7 includes a one-time

inspection already required under

paragraph (e).

• Revise the reference to ‘‘Figure 3 or

Figure 8’’ in paragraph (g)(1) to read

‘‘Figures 3 and 8,’’ because Figures 3

and 8 are both necessary to accomplish

inspections per Plan ‘‘A.’’

• Revise the statement ‘‘Except as

provided by paragraph (b) of this AD’’

in paragraph (i) of the proposed rule to

read ‘‘Except as provided by paragraph

(a)(1)(i) or (b) of this AD.’’ Paragraph

(a)(1)(i) also provides for repairs in

accordance with a method approved by

the Manager, Seattle ACO; or in

accordance with data meeting the type

certification basis of the airplane

approved by a Boeing Company DER.

The FAA concurs with the

commenter’s requests, and has revised

the appropriate paragraphs of this final

rule accordingly.

The same commenter requests that the

FAA revise paragraph (d)(1), paragraph

(e), paragraph (e)(2), paragraph (g)(1),

and paragraph (i) to refer to the original

issue of Boeing Alert Service Bulletin

747–53A2390, dated July 31, 1997, in

addition to Revision 1, as an acceptable

source of service information for the

actions in those paragraphs. The

commenter states that operators that

accomplished requirements in

accordance with the original issue of the

service bulletin should receive credit for

these actions.

The FAA concurs with the intent of

the commenter’s request, and has added

a new note, Note 6, to this AD to state

that accomplishment of the actions

specified in paragraphs (d)(1), (e), (e)(2),

(g)(1), and (i) of this AD, in accordance

with the original issue of Boeing Alert

Service Bulletin 747–53A2390, is

acceptable for compliance with those

paragraphs.

Revise Paragraph (i) To Require FAAApproved Repairs

One commenter requests that the FAA

revise paragraph (i) to require that

damage beyond the repair limits

specified in the service bulletin be

repaired according to a method

approved by the FAA. The commenter

states that operators must contact

Boeing or the FAA to ensure that

damage beyond the specified limits is

repaired so that the repair meets the

FAA type certificate, and to have the

repaired structure evaluated for reduced

inspection thresholds and repeat

intervals. (Structure at fastener holes

that are oversized beyond the limits in

the service bulletin will have reduced

fatigue life, and cracks in the area may

grow rapidly.)

The FAA partially concurs with the

commenter’s request. The FAA

considers that, as proposed, paragraph

(b) of this AD would already require that

operators repair any damage outside the

limits specified in the service bulletin in

accordance with a method approved by

the FAA or 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 Aircraft Certification

Office, to make such findings. However,

the FAA finds that explicitly stating this

requirement in paragraph (i) may clarify

the requirements of that paragraph.

Thus, the FAA has revised paragraph (i)

in this final rule accordingly.

31126 Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations

Add Grace Period for and Clarify

Paragraph (f)(2)

One commenter requests that the FAA

revise the compliance time in paragraph

(f)(2) of the proposed AD from ‘‘Prior to

the accumulation of 20,000 total flight

cycles, or at the time of the next

scheduled inspection of the lower

bulkhead in accordance with paragraph

(a)(2) of this AD, whichever occurs

later,’’ to ‘‘20,000 total flight cycles,

within 1,000 flight cycles of the

effective date of the AD, or within

10,000 flight cycles of the previous

inspections accomplished in accordance

with paragraph (g)(1) of this AD,

whichever occurs latest.’’ The

commenter states that the proposed

compliance time could cause airplanes

to be grounded if an airplane has more

than 20,000 total flight cycles but has

not previously been inspected per

paragraph (a)(2).

The FAA does not concur with the

commenter’s request. The compliance

times in paragraph (f)(2) only apply if an

inspection of the lower bulkhead has

been done per paragraph (a)(2). If an

airplane has not been inspected per

paragraph (a)(2), then the compliance

time in paragraph (f)(1), which includes

a grace period of 1,000 flight cycles after

the effective date of this AD, applies. No

change is necessary in this regard.

Also in reference to paragraph (f)(2),

the commenter notes that paragraph

(a)(2) tells operators how, but not when,

to inspect the bulkhead splice and

bulkhead stringer interfaces. The FAA

infers that the commenter is requesting

that the FAA clarify the reference to

paragraph (a)(2) in paragraph (f)(2) of

this AD, and the FAA concurs with this

request. Paragraph (a)(2)(ii) states that

repetitive inspections are to be

accomplished according to the flight

safety inspection program, as specified

in Figures 1 and 3 of the service

bulletin. Figure 3 specifies the 10,000-

flight-cycle repetitive interval.

Therefore, the FAA finds that paragraph

(f)(2) of this AD should refer to

paragraph (a)(2)(ii) of this AD, and has

revised that paragraph accordingly.

Increase Threshold for Inspections of

Splice Area and Stringer Interface

One commenter requests that the FAA

revise the proposed rule to increase the

compliance threshold for the

inspections of the splice area (from

16,000 total flight cycles) and the

stringer interface (from 20,000 total

flight cycles). The commenter suggests a

threshold of 25,000 total flight cycles.

The commenter bases its request on

inspections of its airplanes, many of

which had more than 25,000 total flight

cycles at the time of inspection. Though

cracks were found, all were small

enough to be removed by oversizing

holes or installing bushing repairs.

The FAA does not concur with the

commenter’s request. Service

information from the airplane

manufacturer shows that large bulkhead

repairs have been necessary on

airplanes in Groups 1 through 3 with as

few as 19,387 total flight cycles. Also,

replacement of bulkhead cap fittings has

been necessary on airplanes in Groups

4 through 18 with as few as 13,206 total

flight cycles. These findings are

consistent with the fact that the subject

cracking is caused by fatigue, which can

initiate cracks on airplanes at a wide

range of flight cycles. In view of this

information, the fact that the commenter

found no large cracks on its airplanes,

though the airplanes had more than

25,000 total flight cycles, does not

justify an increase in the compliance

threshold. The FAA finds that the

proposed compliance times are

necessary to ensure an adequate level of

safety, and no change to the final rule

is necessary in this regard.

Request To Delete References to

Appendices

One commenter requests that the FAA

revise paragraphs (c), (d), (d)(1), and

(d)(2) of the proposed rule, to delete the

references to Appendices C and D of the

service bulletin. The commenter states

that these paragraphs apply to airplanes

in Groups 1 through 3, but Appendices

C and D of the service bulletin only

apply to airplanes in Groups 4 through

22. The commenter also asks the FAA

to revise paragraph (e) to delete the

reference to Appendix B of the service

bulletin, because paragraph (e) applies

to airplanes in Groups 4 through 22, but

Appendix B of the service bulletin only

applies to airplanes in Groups 1 through

3.

The FAA does not concur with the

commenter’s request. The references to

the appendices with which the

commenter is concerned are included in

those paragraphs as a citation of the full

service bulletin reference (Boeing Alert

Service Bulletin 747–53A2390, Revision

1; including Appendices A, B, C, and D;

dated July 6, 2000). If a service bulletin

includes one or more appendices which

are numbered separately from the main

body of the service bulletin, the Office

of the Federal Register requires the FAA

to specify all appendices as part of every

full citation of the service bulletin. No

change to the final rule is necessary in

this regard.

Give Credit for Previous

Accomplishment of Paragraph (e)

One commenter requests that the FAA

revise paragraph (e) of the proposed AD

to give credit for inspections

accomplished prior to the effective date

of the AD. The commenter specifically

requests that the FAA include a grace

period of 6,000 flight cycles since the

last inspection in accordance with

paragraph (e)(1) of the AD. (The

repetitive interval for the subject

inspection is 6,000 flight cycles.)

The FAA concurs with the

commenter’s intent, but notes that credit

for previously accomplished AD actions

is always given by means of the phrase

included in every AD, ‘‘Required as

indicated, unless accomplished

previously.’’ No change to the final rule

is necessary in this regard.

Clarify Paragraphs (d)(2), (e)(2), and

(g)(2)

One commenter requests that the FAA

revise paragraphs (d)(2), (e)(2), and

(g)(2) of the proposed rule to state,

‘‘* * * this paragraph postpones the

repetitive inspection requirements

***’’ rather than, ‘‘* * * this

paragraph terminates the repetitive

inspection requirements.’’ The

commenter states that the actions in the

service bulletin do not terminate

inspections, but rather postpone

inspections until 10,000, 16,000, or

20,000 flight cycles, as applicable, after

modification.

The FAA does not concur with the

commenter’s request. The sentences in

the paragraphs to which the commenter

refers specify termination of the

repetitive inspection requirements

under Plan ‘‘A.’’ The paragraphs to

which the commenter refers clearly state

that inspections must still be

accomplished in accordance with the

after-modification inspection program.

No change to the final rule is necessary

in this regard.

Conclusion

After careful review of the available

data, including the comments 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 1,128 Model

747 series airplanes of the affected

design in the worldwide fleet. The FAA

estimates that 259 airplanes of U.S.

registry will be affected by this AD.

Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations 31127

AD 98–20–25 applies to airplanes

listed in Groups 1 through 3 of the

service bulletin. The detailed visual

inspection that is currently offered as

one alternative for compliance with AD

98–20–25 takes approximately 16 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 $960 per

airplane, per inspection cycle.

For airplanes listed in Groups 1

through 3 in the service bulletin (34

U.S.-registered airplanes), the new

detailed visual, ultrasonic, and open

hole high frequency eddy current

(HFEC) inspections of the upper

bulkhead area that are required by this

AD will take approximately 32 work

hours per airplane to accomplish, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of these inspections on U.S. operators is

estimated to be $65,280, or $1,920 per

airplane, per inspection cycle.

For airplanes listed in Groups 4

through 22 in the service bulletin (191

U.S.-registered airplanes), the new

detailed visual, ultrasonic, and open

hole HFEC inspections of the upper

bulkhead area that are required by this

AD will take approximately 22 work

hours per airplane to accomplish, at an

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of these inspections on U.S. operators is

estimated to be $252,120, or $1,320 per

airplane, per inspection cycle.

For all airplanes listed in the

applicability of this AD (259 U.S.-

registered airplanes), the new detailed

visual, ultrasonic, and open hole HFEC

inspections of the lower bulkhead/

stringer interface area that are required

by this AD will take approximately 30

work hours per airplane to accomplish,

at an average labor rate of $60 per work

hour. Based on these figures, the cost

impact of these required inspections on

U.S. operators is estimated to be

$466,200, or $1,800 per airplane, per

inspection cycle.

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.

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 39–10791 (63 FR

50508, September 22, 1998), and by

adding a new airworthiness directive

(AD), amendment 39–12248, to read as

follows:

2001–11–06 Boeing: Amendment 39–12248.

Docket 98–NM–283–AD. Supersedes AD

98–20–25, Amendment 39–10791.

Applicability: Model 747 series airplanes,

line numbers (L/N) 1 through 1254 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 (j)(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 fatigue cracking of

the skin, splice fittings, bulkhead web, and

outer chord of the body station (BS) 1480

bulkhead at the overwing longeron splice,

which could result in reduced structural

integrity of the fuselage and the inability to

carry limit load, accomplish the following:

Restatement of Requirements of AD 98–20–

25: Repetitive Inspections and Repair

(a) For Model 747–100 series airplanes, L/

N 1 through 87 inclusive: Prior to the

accumulation of 10,000 total flight cycles, or

within 45 days after October 7, 1998 (the

effective date of AD 98–20–25, amendment

39–10791), whichever occurs later,

accomplish either paragraph (a)(1) or (a)(2) of

this AD.

Note 2: Inspections per Boeing Alert

Service Bulletin 747–53A2390, Revision 1;

including Appendices A, B, C, and D; dated

July 6, 2000; have been approved as an

alternative method of compliance for the

actions in paragraphs (a)(1) and (a)(2) of this

AD.

(1) Perform a detailed visual inspection to

detect cracking of the longeron splice fitting

at BS 1480, the forward side of the outer

chord of the BS 1480 bulkhead at the

longeron splice fitting attachment bolts, and

the aft side of the outer chord of the BS 1480

bulkhead within two inches above the outer

chord splice fitting, on both the left and right

sides of the airplane.

Note 3: Figure 5 of Boeing Alert Service

Bulletin 747–53A2390, dated July 31, 1997,

and Revision 1, dated July 6, 2000, provides

an exploded view of the structural

components of the splice area for the purpose

of parts identification. (However, paragraph

(a)(1) of this AD does not require the

inspection described in Figure 5.)

Note 4: 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.’’

(i) If any cracking is detected, 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

31128 Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations

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.

(ii) Repeat the detailed visual inspection

thereafter at intervals not to exceed 250 flight

cycles, until the initial inspection required

by paragraph (a)(2) or (d) of this AD is

accomplished.

(2) Perform detailed visual, ultrasonic, and

open hole high frequency eddy current

(HFEC) inspections to detect cracking of the

upper and lower bulkhead, bulkhead outer

chord, web, skin, splice components, and

lower bulkhead/stringer interface, in

accordance with Figures 5 and 8 of Boeing

Alert Service Bulletin 747–53A2390, dated

July 31, 1997. Additionally, for airplanes on

which the inspection in ‘‘Plan B’’ of the

service bulletin is accomplished, modify the

skin splice plate, the outer chord splice

fitting, and the stringer interface of the lower

bulkhead, in accordance with the

Accomplishment Instructions of the service

bulletin. Accomplishment of these actions

constitutes terminating action for the

repetitive inspection requirements of

paragraph (a)(1) of this AD.

(i) If any cracking is detected, prior to

further flight, repair in accordance with the

service bulletin, except as provided by

paragraph (b) of this AD.

(ii) Repeat the inspections thereafter in

accordance with the flight safety inspection

program specified in Figures 1 and 3 of the

service bulletin.

(b) Where the service bulletin specifies that

the manufacturer may be contacted for

disposition of certain repair conditions,

repair in accordance with a method approved

by the Manager, Seattle ACO; or in

accordance with data meeting the type

certification basis of the airplane approved

by a Boeing Company 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.

New Requirements of This AD: Groups 1

Through 3: Splice Area Work (Compliance

Times)

Note 5: Airplanes inspected in accordance

with paragraph (a)(2) of this AD are not

required to be inspected in accordance with

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

Note 6: Accomplishment of the actions

specified in paragraphs (d)(1), (e), (e)(2),

(g)(1), and (i) of this AD; in accordance with

the original issue of Boeing Alert Service

Bulletin 747–53A2390, dated July 31, 1997;

is acceptable for compliance with those

paragraphs.

(c) For airplanes listed in Groups 1 through

3 in Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including Appendices

A, B, C, and D; dated July 6, 2000; on which

the requirements of paragraph (a)(2) of this

AD have NOT been accomplished prior to the

effective date of this AD: Accomplish

paragraph (d) of this AD at the applicable

time specified in paragraph (c)(1), (c)(2), or

(c)(3) of this AD.

(1) For airplanes on which the inspection

specified in Boeing Service Bulletin 747–53–

2333 has not been accomplished: Inspect

prior to the accumulation of 10,000 total

flight cycles, or within 1,000 flight cycles

after the effective date of this AD, whichever

occurs later.

(2) For airplanes on which the inspection

specified in Boeing Service Bulletin 747–53–

2333 has been accomplished, but the full

modification specified in that service bulletin

has not been accomplished: Inspect at the

later of the times specified in paragraphs

(c)(2)(i) and (c)(2)(ii) of this AD.

(i) Prior to the accumulation of 10,000 total

flight cycles, or within 2,000 flight cycles

after accomplishment of the last inspection

in accordance with Boeing Service Bulletin

747–53–2333, whichever occurs first.

(ii) Within 1,000 flight cycles after the

effective date of this AD.

(3) For airplanes on which the full

modification specified in Boeing Service

Bulletin 747–53–2333 has been

accomplished: Inspect at the later of the

times specified in paragraphs (c)(3)(i) and

(c)(3)(ii) of this AD.

(i) Prior to the accumulation of 16,000 total

flight cycles, or within 6,000 flight cycles

after accomplishment of the full modification

in accordance with Boeing Service Bulletin

747–53–2333, whichever occurs first.

(ii) Within 1,000 flight cycles after the

effective date of this AD.

Groups 1 Through 3: Splice Area Work

(Inspections)

(d) For airplanes listed in Groups 1 through

3 in Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including Appendices

A, B, C, and D; dated July 6, 2000; on which

the requirements of paragraph (a)(2) of this

AD have NOT been accomplished prior to the

effective date of this AD: At the applicable

time specified in paragraph (c) of this AD,

accomplish paragraph (d)(1) or (d)(2) of this

AD. Accomplishment of the requirements of

this paragraph constitutes terminating action

for the repetitive inspection requirements

specified in paragraph (a)(1) of this AD, or,

for the upper bulkhead splice area ONLY, for

the inspection requirements specified in

paragraph (a)(2) of this AD.

(1) Plan ‘‘A’’: Perform detailed visual,

ultrasonic, and HFEC inspections to detect

cracking of the splice area, in accordance

with Plan ‘‘A’’ and Figure 5, as defined in the

Accomplishment Instructions of Boeing Alert

Service Bulletin 747–53A2390, Revision 1;

including Appendices A, B, C, and D; dated

July 6, 2000. Repeat the inspections

thereafter in accordance with the flight safety

inspection program as specified under Plan

‘‘A’’ and Figure 1 of the service bulletin.

(2) Plan ‘‘B’’: Modify the skin splice plate

and outer chord splice fitting in accordance

with Plan ‘‘B,’’ as defined in the

Accomplishment Instructions of Boeing Alert

Service Bulletin 747–53A2390, Revision 1;

including Appendices A, B, C, and D; dated

July 6, 2000. Perform HFEC inspections and

modification, then accomplish repeat open

hole HFEC inspections, in accordance with

the after-modification inspection program, as

specified under Plan ‘‘B’’ and Figure 1 of the

service bulletin. Accomplishment of the

modification and inspections in accordance

with this paragraph terminates the repetitive

inspection requirements in paragraph (d)(1)

of this AD.

Groups 4 Through 22: Splice Area Work

(Compliance Time and Inspections)

(e) For airplanes listed in Groups 4 through

22 in Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including Appendices

A, B, C, and D; dated July 6, 2000: Prior to

the accumulation of 16,000 total flight cycles,

or within 1,000 flight cycles after the

effective date of this AD, whichever occurs

later, perform detailed visual and ultrasonic

inspections to detect cracking of the

bulkhead forward flange in accordance with

Figure 7 of the service bulletin, and

accomplish the requirements of either

paragraph (e)(1) or (e)(2) of this AD.

(1) Plan ‘‘A’’: Perform open hole HFEC

inspections to detect cracking of the splice

area, in accordance with Plan ‘‘A’’ and Figure

6, as defined in the Accomplishment

Instructions of the service bulletin. Repeat

the inspections thereafter in accordance with

the flight safety inspection program as

specified under Plan ‘‘A’’ and in Figure 2 of

the service bulletin.

(2) Plan ‘‘B’’: Perform open hole HFEC

inspections and modification of the upper

bulkhead, bulkhead outer chord, web, skin,

and splice components; in accordance with

Plan ‘‘B,’’ as defined in the Accomplishment

Instructions of Boeing Alert Service Bulletin

747–53A2390, Revision 1; including

Appendices A, B, C, and D; dated July 6,

2000. Thereafter, repeat the open hole HFEC

inspections in accordance with the aftermodification inspection program as specified

under Plan ‘‘B’’ and Figure 2 of the service

bulletin. Accomplishment of the

modification and inspections in accordance

with this paragraph terminates the repetitive

inspection requirements specified in

paragraph (e)(1) of this AD.

All Airplanes: Lower Bulkhead/Stringer

Interface Work (Compliance Times)

(f) For all airplanes (L/N 1 through 1254

inclusive): At the applicable time specified in

paragraph (f)(1) or (f)(2) of this AD,

accomplish paragraph (g) of this AD.

(1) For airplanes on which an inspection of

the lower bulkhead has NOT been

accomplished prior to the effective date of

this AD in accordance with paragraph (a)(2)

of this AD: Inspect prior to the accumulation

of 20,000 total flight cycles, or within 1,000

flight cycles after the effective date of this

AD, whichever occurs later.

(2) For airplanes on which an inspection of

the lower bulkhead HAS been accomplished

prior to the effective date of this AD in

accordance with paragraph (a)(2) of this AD:

Inspect prior to the accumulation of 20,000

total flight cycles, or at the time of the next

scheduled inspection of the lower bulkhead

in accordance with paragraph (a)(2)(ii) of this

AD, whichever occurs later.

All Airplanes: Lower Bulkhead/Stringer

Interface Work (Inspections)

(g) For all airplanes (L/N 1 through 1254

inclusive): At the applicable time specified in

paragraph (f) of this AD, accomplish

paragraph (g)(1) or (g)(2) of this AD. For

Federal Register / Vol. 66, No. 112 / Monday, June 11, 2001 / Rules and Regulations 31129

airplanes having L/N 1 through 87 inclusive,

accomplishment of the requirements of this

paragraph constitutes terminating action for

the inspection requirements specified in

paragraph (a)(2) of this AD for the lower

bulkhead/stringer interface area ONLY.

(1) Plan ‘‘A’’: Perform detailed visual and

either ultrasonic or open hole HFEC

inspections, as applicable, to detect cracking

of the lower bulkhead/stringer interface area,

in accordance with Plan ‘‘A’’ and Figure 8,

as defined in the Accomplishment

Instructions of Boeing Alert Service Bulletin

747–53A2390, Revision 1; including

Appendices A, B, C, and D; dated July 6,

2000. Repeat the inspections thereafter in

accordance with the flight safety program as

specified under Plan ‘‘A’’ and Figures 3 and

8 of the service bulletin.

(2) Plan ‘‘B’’: Except as provided by

paragraph (h) of this AD, perform open hole

HFEC inspections and modification of the

lower bulkhead/stringer interface area, in

accordance with Plan ‘‘B’’ and Figure 19, as

defined in the Accomplishment Instructions

of Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including Appendices

A, B, C, and D; dated July 6, 2000. Thereafter,

repeat the detailed visual and either

ultrasonic or open hole HFEC inspections, as

applicable, in accordance with the aftermodification inspection program as specified

under Plan ‘‘B’’ and Figures 3 and 8 of the

service bulletin. Accomplishment of the

modification and inspections in accordance

with this paragraph terminates the repetitive

inspection requirements specified in

paragraph (g)(1) of this AD.

Airplanes Modified With Original Service

Bulletin: Post-Modification Work

(h) For any airplane (L/N 1 through 1254

inclusive) on which the modification

specified in paragraph (g)(2) was

accomplished prior to the effective date of

this AD in accordance with the original issue

of Boeing Alert Service Bulletin 747–

53A2390, dated July 31, 1997: Prior to the

accumulation of 20,000 total flight cycles, or

within 2,000 flight cycles after the effective

date of this AD, whichever occurs later,

accomplish post-modification work in

accordance with Figure 26 of Boeing Alert

Service Bulletin 747–53A2390, Revision 1;

including Appendices A, B, C, and D; dated

July 6, 2000.

Repair

(i) Except as provided by paragraph (a)(1)(i)

or (b) of this AD, if any cracking is detected

during any inspection required by this AD,

prior to further flight, repair in accordance

with Boeing Alert Service Bulletin 747–

53A2390, Revision 1; including Appendices

A, B, C, and D; dated July 6, 2000. If any

damage is found that is beyond the limits

specified in the service bulletin, prior to

further flight, repair in accordance with a

method approved by the Manager, Seattle

ACO; or in accordance with data meeting the

type certification basis of the airplane

approved by a Boeing Company 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

(j)(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

98–20–25, amendment 39–10791, are

approved as alternative methods of

compliance with paragraph (a) of this AD.

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

(k) 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

(l) Except as provided by paragraphs (a)(1),

(a)(1)(i), (a)(1)(ii), (b), and (i) of this AD, the

actions shall be done in accordance with

Boeing Alert Service Bulletin 747–53A2390,

dated July 31, 1997; or Boeing Alert Service

Bulletin 747–53A2390, Revision 1; including

Appendices A, B, C, and D; dated July 6,

2000; as applicable.

(1) The incorporation by reference of

Boeing Alert Service Bulletin 747–53A2390,

Revision 1; including Appendices A, B, C,

and D; dated July 6, 2000; is approved by the

Director of the Federal Register in accordance

with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The incorporation by reference of

Boeing Alert Service Bulletin 747–53A2390,

dated July 31, 1997, was approved previously

by the Director of the Federal Register as of

October 7, 1998 (63 FR 50508, September 22,

1998).

(3) 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

(m) This amendment becomes effective on

July 16, 2001.

Issued in Renton, Washington, on May 25,

2001.

Vi L. Lipski,

Manager, Transport Airplane Directorate,

Aircraft Certification Service.

[FR Doc. 01–14001 Filed 6–8–01; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NM–156–AD; Amendment

39–12254; AD 2001–11–11]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 737, 747, and 777 Series

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to certain Boeing Model 737,

747, and 777 series airplanes, that

requires replacement of the seat track

fittings on all passenger seats with new,

improved fittings. The actions specified

by this AD are intended to prevent

unrestrained movement of the passenger

seats during high forward deceleration

of the airplane, which could result in

injury to the passengers or crew

members during an emergency landing.

DATES: Effective July 16, 2001.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of July 16,

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: Jan

Risheim, Aerospace Engineer, Airframe

Branch, ANM–120S, FAA, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington;

telephone (425) 227–1675; 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 737, 747, and 777 series

airplanes was published in the Federal

Register on December 22, 2000 (65 FR

80794). That action proposed to require

replacement of the seat track fittings on

all passenger seats with new, improved

fittings.