Federal Register / Vol. 63, No. 141 /Thursday, July 23, 1998 /Rules and Regulations 39487

Issued in Renton, Washington, on July 15,

1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–19457 Filed 7–22–98; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–82–AD; Amendment

39–10672; AD 98–15–21]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 747–100 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 wing front spar web

above engine numbers 2 and 3, and to

detect cracked or broken fasteners in the

web; and repair, if necessary. That AD

also provides an optional terminating

action for the repetitive inspections.

This amendment requires various

improved inspections. This amendment

is prompted by a report indicating that

the existing inspections do not

adequately detect vertical cracks. The

actions specified by this AD are

intended to prevent fuel leakage onto an

engine and a resultant fire due to

cracked or broken fasteners in the wing

front spar.

DATES: Effective August 27, 1998.

The incorporation by reference of

Boeing Alert Service Bulletin 747–

57A2266, Revision 5, dated August 3,

1995, as listed in the regulations, is

approved by the Director of the Federal

Register as of August 27, 1998.

The incorporation by reference of

Boeing Service Bulletin 747–57A2266,

Revision 3, dated March 31, 1994; and

Boeing Service Bulletin 747–57A2266,

Revision 4, dated November 3, 1994,

was approved previously by the Director

of the Federal Register as of March 23,

1995 (60 FR 9613, February 21, 1995).

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:

Tamara L. Anderson, Aerospace

Engineer, Airframe Branch, ANM–120S,

FAA, Transport Airplane Directorate,

Seattle Aircraft Certification Office,

1601 Lind Avenue, SW., Renton,

Washington 98055–4056; telephone

(425) 227–2771; fax (425) 227–1181.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39)

by superseding AD 95–02–15,

amendment 39–9134 (60 FR 9613,

February 21, 1995), which is applicable

to certain Boeing Model 747–100 series

airplanes, was published in the Federal

Register on April 14, 1998 (63 FR

18167). The action proposed to

supersede AD 95–02–15 to continue to

require repetitive inspections to detect

cracking of the wing front spar web

above engine numbers 2 and 3, and to

detect cracked or broken fasteners in the

web; and repair, if necessary. That

action also continues to provide for an

optional terminating action for the

repetitive inspections. The action

proposed to require various improved

inspections.

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.

The commenter supports the

proposed rule.

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 190 Boeing

Model 747–100 series airplanes of the

affected design in the worldwide fleet.

The FAA estimates that 95 airplanes of

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

The actions that are currently

required by AD 95–02–15, and retained

in this AD, take approximately 70 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 inspection on

U.S. operators is estimated to be

$399,000, or $4,200 per airplane, per

inspection cycle.

For airplanes identified as

Configuration A in the referenced alert

service bulletin, the new actions that are

required in this AD will take

approximately 60 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

new inspection requirements of this AD

on those U.S. operators is estimated to

be $3,600 per airplane, per inspection

cycle.

For airplanes identified as

Configuration B in the referenced alert

service bulletin, the new actions that are

required in this AD will take

approximately 40 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

new inspection requirements of this AD

on U.S. operators is estimated to be

$2,400 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.

Should an operator elect to

accomplish the optional terminating

action (fastener replacement between

FSS 570 and FSS 684) that is provided

by this AD action, it would take

approximately 306 work hours to

accomplish it, at an average labor rate of

$60 per work hour. The cost of required

parts would be approximately $15,478.

Based on these figures, the cost impact

of the optional terminating action will

be $33,838 per airplane.

Regulatory Impact

The regulations adopted herein will

not have substantial direct effects on the

States, on the relationship between the

national government and the States, or

on the distribution of power and

responsibilities among the various

levels of government. Therefore, in

accordance with Executive Order 12612,

it is determined that this final rule does

not have sufficient federalism

implications to warrant the preparation

of a Federalism Assessment.

For the reasons discussed above, I

certify that this action (1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

FR 11034, February 26, 1979); and (3)

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
39488 Federal Register / Vol. 63, No. 141 /Thursday, July 23, 1998 /Rules and Regulations

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 39–9134 (60 FR

9613, February 21, 1995), and by adding

a new airworthiness directive (AD),

amendment 39–10672, to read as

follows:

98–15–21 Boeing: Amendment 39–10672.

Docket 97–NM–82–AD. Supersedes AD

95–02–15, Amendment 39–9134.

Applicability: Model 747–100 series

airplanes; as listed in Boeing Alert Service

Bulletin 747–57A2266, Revision 5, dated

August 3, 1995; 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) 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 fuel leakage onto an engine and

a resultant fire, accomplish the following:

Restatement of Requirements of AD 95–02–

15, Amendment 39–9134

(a) For airplanes on which the terminating

action (fastener replacement) specified in

Boeing Service Bulletin 747–57A2266, dated

June 6, 1991; Revision 1, dated May 21, 1992;

or Revision 2, dated June 10, 1993; has not

been accomplished: Prior to the

accumulation of 13,000 total flight cycles, or

within 9 months after March 23, 1995 (the

effective date of AD 95–02–15, amendment

39–9134), or within 2,000 flight cycles after

the immediately preceding inspection

accomplished in accordance with AD 92–07–

11, amendment 39–8207, whichever occurs

latest, accomplish the inspections specified

in paragraphs (a)(1), (a)(2), and (a)(3) of this

AD in accordance with Boeing Service

Bulletin 747–57A2266, Revision 3, dated

March 31, 1994, or Revision 4, dated

November 3, 1994. Repeat these inspections

thereafter at intervals not to exceed 2,000

flight cycles until the inspections required by

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

are accomplished.

(1) Perform a detailed visual inspection to

detect cracking of the wing front spar chords,

stiffeners, and rib posts between the fastener

heads between FSS 570 and FSS 684; and

(2) Perform an ultrasonic inspection of the

web under the upper and lower chord

footprints to detect cracking of the wing front

spar web between FSS 570 and FSS 684; and

(3) Perform an ultrasonic inspection of the

fasteners in the web-to-chords, and of the

fasteners in the top two and bottom two rows

in the web-to-stiffeners and web-to-rib posts

of the wing front spar to detect cracked or

broken fasteners between FSS 570 and FSS

684.

(b) For airplanes on which the terminating

action (fastener replacement) specified in

Boeing Service Bulletin 747–57A2266, dated

June 6, 1991; Revision 1, dated May 21, 1992;

or Revision 2, dated June 10, 1993; has been

accomplished: Within 18 months after

accomplishing the terminating action

specified in the original issue, Revision 1, or

Revision 2 of the service bulletin, or within

9 months after March 23, 1995, whichever

occurs later, accomplish the inspections

specified in paragraphs (b)(1), (b)(2), and

(b)(3) of this AD, in accordance with Boeing

Service Bulletin 747–57A2266, Revision 3,

dated March 31, 1994, or Revision 4, dated

November 3, 1994. Repeat these inspections

thereafter at intervals not to exceed 2,000

flight cycles until the inspections required by

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

are accomplished.

(1) Perform a detailed visual inspection of

the wing front spar chords, stiffeners, and rib

posts between the fastener heads between

FSS 570 and FSS 684; and

(2) Perform an ultrasonic inspection of the

web under the upper and lower chord

footprints to detect cracking of the wing front

spar web between FSS 570 and FSS 636 and

between FSS 675 and FSS 684; and

(3) Perform an ultrasonic inspection of the

fasteners in the web-to-chords, and of the

fasteners in the top two rows and bottom two

rows in the web-to-stiffeners and web-to-rib

posts of the wing front spar to detect cracked

or broken fasteners between FSS 570 and FSS

636 and between FSS 675 and 684.

New Requirements of this AD

(c) For airplanes identified as

Configuration A in Boeing Alert Service

Bulletin 747–57A2266, Revision 5, dated

August 3, 1995: Prior to the accumulation of

13,000 total flight cycles, or within 6 months

after the effective date of this AD, or within

2,000 flight cycles after the immediately

preceding inspection accomplished in

accordance with paragraph (a) or (b) of this

AD, whichever occurs latest, accomplish the

inspections specified in paragraphs (c)(1),

(c)(2), (c)(3), and (c)(4) of this AD, in

accordance with Figure 3 of Boeing Alert

Service Bulletin 747–57A2266, Revision 5,

dated August 3, 1995. Repeat these

inspections thereafter at intervals not to

exceed 2,000 flight cycles. Accomplishment

of these inspections terminates the

inspections required by paragraphs (a) and

(b) of this AD.

(1) Perform a detailed visual inspection to

detect damage and fuel leaks in the general

area of the web of the wing front spar

between FSS 570 and FSS 684.

(2) Perform an eddy current inspection to

detect cracks along the web near the edges of

the vertical flange of the upper and lower

chords of the wing front spar between FSS

570 and FSS 684.

(3) Perform an ultrasonic inspection to

detect cracks in the web around the first two

fastener holes in the stiffeners and rib posts

between FSS 570 and FSS 684.

(4) Perform an ultrasonic inspection to

detect cracked or broken fasteners in the

fasteners attaching only the web to the

chords, in the top two and bottom two rows

of the fasteners attaching the web to the

stiffeners, and in the top two and bottom two

rows of the fasteners attaching the web to the

rib posts. This inspection area is located

between FSS 570 and FSS 684.

(d) For airplanes identified as

Configuration B in Boeing Alert Service

Bulletin 747–57A2266, Revision 5, dated

August 3, 1995: Within 18 months following

accomplishment of the terminating action

(fastener replacement) specified in Boeing

Service Bulletin 747–57A2266, dated June 6,

1991, Revision 1, dated May 21, 1992, or

Revision 2, dated June 10, 1993; or within 12

months after the effective date of this AD; or

within 2,000 flight cycles after the

immediately preceding inspection

accomplished in accordance with paragraph

(a) or (b) of this AD; whichever occurs latest;

accomplish the inspections specified in

paragraphs (d)(1), (d)(2), (d)(3), and (d)(4) of

this AD in accordance with Figure 4 of

Boeing Alert Service Bulletin 747–57A2266,

Revision 5, dated August 3, 1995. Repeat

these inspections thereafter at intervals not to

exceed 2,000 flight cycles. Accomplishment

of these inspections terminates the

inspections required by paragraphs (a) and

(b) of this AD.

(1) Perform a detailed visual inspection to

detect damage and fuel leaks in the general

area of the web of the wing front spar

between FSS 570 and FSS 636 and between

FSS 675 and FSS 684.

(2) Perform an eddy current inspection to

detect cracks along the web near the edges of

the vertical flange of the upper and lower

chords of the wing front spar between FSS

570 and FSS 636 and between FSS 675 and

FSS 684.

(3) Perform an ultrasonic inspection to

detect cracks in the web around the first two

fastener holes in the stiffeners and rib posts

between FSS 570 and FSS 636 and between

FSS 675 and FSS 684.

(4) Perform an ultrasonic inspection to

detect cracked or broken fasteners in the

fasteners attaching only the web to the

chords, in the top two and bottom two rows

of the fasteners attaching the web to the
Federal Register / Vol. 63, No. 141 /Thursday, July 23, 1998 /Rules and Regulations 39489

stiffeners, and in the top two and bottom two

rows of the fasteners attaching the web to the

rib posts. This inspection area is located

between FSS 570 and FSS 636 and between

FSS 675 and FSS 684.

(e) If any discrepancy (i.e., cracking, fuel

leakage, broken fasteners) is detected during

any inspection required by this AD, prior to

further flight, repair in accordance with

paragraphs E. and H. (as applicable) of the

Accomplishment Instructions of Boeing

Service Bulletin 747–57A2266, Revision 3,

dated March 31, 1994; Boeing Service

Bulletin 747–57A2266, Revision 4, dated

November 3, 1994; or Boeing Alert Service

Bulletin 747–57A2266, Revision 5, dated

August 3, 1995. Thereafter, continue to

inspect the remaining fasteners in accordance

with paragraph (c) or (d) of this AD, as

applicable, until the terminating action

specified in paragraph (f) of this AD is

accomplished. If any crack is found that

cannot be removed by oversizing the fastener

hole, prior to further flight, repair it in

accordance with a method approved by the

Manager, Seattle Aircraft Certification Office

(ACO), FAA, Transport Airplane Directorate.

(f) Replacement of the fasteners in the webto-chords and of the fasteners in the web-tostiffeners and web-to-rib posts, as specified

in Boeing Service Bulletin 747–57A2266,

Revision 3, dated March 31, 1994; Revision

4, dated November 3, 1994; or Revision 5,

dated August 3, 1995; with oversized

fasteners on each wing spar in accordance

with the service bulletin constitutes

terminating action for the repetitive

inspections required by paragraphs (a), (b),

(c), (d), and (e) of this AD.

(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

Aircraft Certification Office (ACO), FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Seattle ACO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

(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.

(i) The actions shall be done in accordance

with Boeing Service Bulletin 747–57A2266,

Revision 3, dated March 31, 1994; Boeing

Service Bulletin 747–57A2266, Revision 4,

dated November 3, 1994; and Boeing Alert

Service Bulletin 747–57A2266, Revision 5,

dated August 3, 1995.

(1) The incorporation by reference of

Boeing Alert Service Bulletin 747–57A2266,

Revision 5, dated August 3, 1995, 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 Service Bulletin 747–57A2266,

Revision 3, dated March 31, 1994; and

Boeing Service Bulletin 747–57A2266,

Revision 4, dated November 3, 1994, was

approved previously by the Director of the

Federal Register as of March 23, 1995 (60 FR

9613, February 21, 1995).

(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.

(j) This amendment becomes effective on

August 27, 1998.

Issued in Renton, Washington, on July 15,

1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 98–19455 Filed 7–22–98; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–ANE–35–AD; Amendment

39–10668; AD 98–15–17]

RIN 2120–AA64

Airworthiness Directives; General

Electric Company CF6–80A3 Series

Turbofan Engines

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment adopts a

new airworthiness directive (AD) that is

applicable to General Electric Company

CF6–80A3 series turbofan engines. This

action requires initial and repetitive onwing borescope inspections of the left

hand aft mount link assembly for cracks,

bearing migration, and bearing race

rotation, and, if necessary, replacement

with serviceable parts. This amendment

is prompted by a report of a fractured

left hand aft mount link discovered

during a scheduled engine removal. The

actions specified in this AD are

intended to prevent left hand aft mount

link failure, which can result in adverse

redistribution of the aft mount loads and

possible aft mount system failure.

DATES: Effective August 7, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of August 7,

1998.

Comments for inclusion in the Rules

Docket must be received on or before

September 21, 1998.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), New England

Region, Office of the Regional Counsel,

Attention: Rules Docket No. 98–ANE–

35–AD, 12 New England Executive Park,

Burlington, MA 01803–5299. Comments

may also be sent via the Internet using

the following address: ‘‘9-adengineprop@faa.dot.gov’’. Comments

sent via the Internet must contain the

docket number in the subject line.

The service information referenced in

this AD may be obtained from Rohr,

Inc., 850 Lagoon Dr., Chula Vista, CA

91910–2098; telephone (619–691–3102),

fax (619–498–7215). This information

may be examined at the FAA, New

England Region, Office of the Regional

Counsel, 12 New England Executive

Park, Burlington, MA; or at the Office of

the Federal Register, 800 North Capitol

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

FOR FURTHER INFORMATION CONTACT:

William S. Ricci, Aerospace Engineer,

Engine Certification Office, FAA, Engine

and Propeller Directorate, 12 New

England Executive Park, Burlington, MA

01803–5299; telephone (781) 238–7742,

fax (781) 238–7199.

SUPPLEMENTARY INFORMATION: The

Federal Aviation Administration (FAA)

has received a report of a fractured left

hand aft mount link discovered during

a scheduled engine removal of a General

Electric Company (GE) CF6–80A3 series

turbofan engine. Failure analysis

revealed a fatigue type fracture with no

metallurgical anomalies and no

geometric discrepancies in the area of

the crack origin. Over the course of the

investigation of the cracked left hand aft

mount link assembly and the review of

other link assemblies returned from

service, two conditions were noted that

individually could be considered benign

but when combined could result in

higher stress levels and the reduced

fatigue capability of link assemblies.

The first condition is the incorrect

orientation of the entry slots of the

spherical bearing assembly and the

second condition is high friction

between the bearing and the race

resulting from contamination between

faying bearing surfaces. This condition,

if not corrected, could result in left hand

aft mount link failure, which can result

in adverse redistribution of the aft

mount loads and possible aft mount

system failure.

On May 20, 1998, the Direction

Generale de L’Aviation Civile (DGAC),

the airworthiness authority of France,

issued AD 98–205–260(B), applicable to

Airbus A310 aircraft, addressing this

unsafe condition by requiring initial and

repetitive on-wing borescope

inspections of the left hand aft mount

link assembly for cracks, bearing