63262 Federal Register / Vol. 62, No. 229 / Friday, November 28, 1997 / Rules and Regulations

This incorporation by reference was

approved by the Director of the Federal

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

and 1 CFR part 51. Copies may be obtained

from Fokker Services B.V., Technical

Support Department, P.O. Box 75047, 1117

ZN Schiphol Airport, The Netherlands.

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.

Note 3: The subject of this AD is addressed

in Netherlands airworthiness directive BLA

94–114(A), dated August 5, 1994.

(g) This amendment becomes effective on

January 2, 1998.

Issued in Renton, Washington, on

November 19, 1997.

Stewart R. Miller,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–31021 Filed 11–26–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–185–AD; Amendment

39–10218; AD 97–24–11]

RIN 2120–AA64

Airworthiness Directives; Fokker

Model F28 Mark 0100 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to certain Fokker Model F28

Mark 0100 series airplanes, that requires

repetitive inspections of certain flanges

and finger strips at rib 5.0 of the vertical

stabilizer to detect fatigue cracking, and

repairs, if necessary. This amendment

also requires modifications that would

strengthen the torsion box at rib 5.0 and

prevent fatigue cracking; one of these

modifications constitutes terminating

action for the repetitive inspections.

This amendment is prompted by reports

indicating that, during full-scale fatigue

testing, cracking has been found on the

vertical stabilizer of the test article. The

actions specified by this AD are

intended to detect and prevent fatigue

cracking in the subject area, which, if

not corrected, could reduce the

structural integrity of the vertical

stabilizer.

DATES: Effective January 2, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 2,

1998.

ADDRESSES: The service information

referenced in this AD may be obtained

from Fokker Services B.V., Technical

Support Department, P.O. Box 75047,

1117 ZN Schiphol Airport, The

Netherlands. 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:

International Branch, ANM–116, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2110;

fax (425) 227–1149.

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 Fokker

Model F28 Mark 0100 series airplanes

was published in the Federal Register

on January 14, 1997 (62 FR 1866). That

action proposed to require repetitive

eddy current inspections to detect

fatigue cracking of the left-hand and

right-hand flanges and finger strips at

rib 5.0 of the vertical stabilizer, and

repair, if necessary. That action also

proposed to require modification of rib

5.0 by the installation of a stiffener to

the torsion box; this modification would

be preceded by an eddy current

inspection to detect fatigue cracking,

and repair, if necessary.

Accomplishment of this modification

constitutes terminating action for the

repetitive inspection requirements. In

addition, that action proposed to require

another modification of rib 5.0 by coldexpanding certain bolt holes on the

torsion box.

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.

One commenter supports the

proposed rule.

Requests To Extend the Compliance

Time

Two commenters request that the

compliance time for accomplishing the

proposed eddy current inspection and

modification of rib 5.0 of the vertical

stabilizer [required by paragraphs (b)(1)

and (b)(2) of the proposed AD,

respectively] be extended from ‘‘prior to

the accumulation of 13,500 total

landings, or within 6 months * * * ’’ to

‘‘prior to the accumulation of 16,000

total landings or within 12 months.’’

One of these commenters states that it

is currently performing the subject

inspection and modification during its

F100 ‘‘Q’’ check visit, which is currently

scheduled at 16,000 flight hours or

16,000 landings, whichever occurs first.

The commenter also states that ten of its

airplanes, which have accumulated

between 10,972 and 14,976 flight cycles,

have been inspected and modified. This

commenter points out that no cracks

have been detected on these airplanes.

This commenter contends that

accomplishment of the repetitive

inspections required by paragraph (a) of

the proposed AD at 2,000 flight cycle

intervals will assure that the required

level of safety is maintained.

The FAA does not concur with the

commenters’ request to extend the

compliance time. The FAA points out

that the proposed compliance time of

paragraphs (b)(1) and (b)(2) of the AD

was developed in consideration of not

only the degree of urgency associated

with addressing the unsafe condition,

but such factors as the manufacturer’s

and the foreign airworthiness

authority’s [i.e., Rijksluchtvaartdienst

(RLD)] recommendations, the

availability of required parts, and the

practical aspect of installing the

required modification within an interval

of time that parallels normal scheduled

maintenance for the majority of affected

operators. The FAA also has consulted

with the manufacturer and RLD and

determined that 13,500 flight cycles

represents the maximum number of

flight cycles allowable for the affected

airplanes to continue to operate prior to

accomplishing the required inspections

and modification without compromising

safety. The proposed compliance times

are based on results of fatigue tests and

analysis of the effects of the thrust

reverser loads on adjacent structure.

In addition, the FAA finds that the

commenters have not submitted any

data to substantiate why a 2,500 flightcycle extension of the compliance time

would not compromise safety, nor have

the commenters addressed whether

further inspections would be necessary

to ensure the long term operational

safety. However, under the provisions of

paragraph (e) of the final rule, the FAA

may approve requests for adjustments to

the compliance time if sufficient data

are submitted to substantiate that such

an adjustment would provide an

acceptable level of safety.

Conclusion

After careful review of the available

data, including the comments noted
Federal Register / Vol. 62, No. 229 / Friday, November 28, 1997 / Rules and Regulations 63263

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule as proposed.

Cost Impact

The FAA estimates that 122 Fokker

Model F28 Mark 0100 series airplanes of

U.S. registry will be affected by this

proposed AD.

Approximately 77 airplanes will be

required to conduct repetitive

inspections of the left-hand and righthand flanges and finger strips at rib 5.0

of the vertical stabilizer. It will take

approximately 10 work hours per

airplane to accomplish each required

inspection. The average labor rate is $60

per work hour. Based on these figures,

the cost impact of these inspections

required by this AD on U.S. operators of

these airplanes is estimated to be

$46,200, or $600 per airplane, per

inspection.

Approximately 77 airplanes also will

be required to accomplish the

installation of steel reinforcement in the

torsion box at rib 5.0 of the vertical

stabilizer. It will take approximately 170

work hours per airplane to accomplish

this modification (including a premodification inspection). The average

labor rate is $60 per work hour.

Required parts will cost approximately

$27,000. Based on these figures, the cost

impact of this modification required by

this AD on U.S. operators of these

airplanes is estimated to be $2,864,400,

or $37,200 per airplane.

Approximately 122 airplanes will be

required to accomplish the cold

expansion of holes in the torsion box at

rib 5.0 of the vertical stabilizer. It will

take approximately 17 work hours per

airplane to accomplish this

modification, or approximately 8 work

hours per airplane if this modification is

done at the same time as the installation

of steel reinforcement. The average labor

rate is $60 per work hour. Required

parts will cost approximately $206.

Based on these figures, the cost impact

of this modification required by this AD

on U.S. operators of these airplanes is

estimated to be between $83,692 and

$149,572, or between $686 and $1,226

per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the requirements of this AD action, and

that no operator would accomplish

those actions in the future if this AD

were not adopted.

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

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

adding the following new airworthiness

directive:

97–24–11 Fokker: Amendment 39–10218.

Docket 96–NM–185–AD.

Applicability: Model F28 Mark 0100 series

airplanes having the serial numbers specified

in Table 1 of this AD; certificated in any

category.

TABLE 1.—SERIAL NUMBERS OF

AIRPLANES SUBJECT TO THIS AD

11244 through 11460, inclusive

11463 through 11469, inclusive

11471

11474 through 11483, inclusive

11489 through 11491, inclusive

11497 through 11499, inclusive

11501

11502

11504

11506

TABLE 1.—SERIAL NUMBERS OF AIRPLANES SUBJECT TO THIS AD—

Continued

11507

11512 through 11515, inclusive

11517

11520

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

otherwise modified, altered, or repaired in

the area subject to the requirements of this

AD. For airplanes that have been modified,

altered, or repaired so that the performance

of the requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (e) 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 prevent fatigue cracking in

the vertical stabilizer, which consequently

could reduce its structural integrity,

accomplish the following

(a) For airplanes having serial numbers

11244 through 11419, inclusive, and 11421:

Except as provided by paragraph (c) of this

AD, prior to the accumulation of 8,500 total

landings or within 30 days after the effective

date of this AD, whichever occurs later,

perform an eddy current inspection to detect

fatigue cracking in the left-hand and righthand flanges and finger strips at rib 5.0 of the

vertical stabilizer, in accordance with Fokker

Service Bulletin SBF100–55–019, Revision 1,

dated May 19, 1993.

(1) If no cracking is detected, repeat this

inspection thereafter at intervals not to

exceed 2,000 landings until the requirements

of paragraph (b) of this AD are accomplished.

(2) If any cracking is detected, prior to

further flight, repair in accordance with a

method approved by the Manager,

International Branch, ANM–116, FAA,

Transport Airplane Directorate.

(b) For airplanes with serial numbers

11244 through 11419 inclusive, and 11421,

accomplish the requirements of both

paragraphs (b)(1) and (b)(2) of this AD:

(1) Except as provided by paragraph (c) of

this AD, prior to the accumulation of 13,500

total landings, or within 6 months after the

effective date of this AD, whichever occurs

later, perform an eddy current inspection to

detect fatigue cracking in the left-hand and

right-hand flanges and finger strips at rib 5.0

of the vertical stabilizer, in accordance with

Part 1 of the Accomplishment Instructions of

Fokker Service Bulletin SBF100–55–018,

Revision 1, dated December 27, 1993.

(i) If no cracking is detected, prior to

further flight, accomplish the requirements of

paragraph (b)(2) of this AD.

(ii) If any cracking is detected, prior to

further flight, repair in accordance with a

method approved by the Manager,

International Branch, ANM–116, and
63264 Federal Register / Vol. 62, No. 229 / Friday, November 28, 1997 / Rules and Regulations

accomplish the requirements of paragraph

(b)(2) of this AD.

(2) After accomplishing the requirements

of paragraph (b)(1) of this AD, modify rib 5.0

of the vertical stabilizer by installing new

stiffening, in accordance with Part 2 of the

Accomplishment Instructions of Fokker

Service Bulletin SBF100–55–018, Revision 1,

dated December 27, 1993. Accomplishment

of this modification constitutes terminating

action for the repetitive inspections required

by paragraph (a) of this AD.

(c) The following exceptions apply with

regard to the requirements of paragraphs (a)

and (b) of this AD:

(1) Accomplishment of the inspection

specified in paragraph (a) and (b)(1) of this

AD is not required if the modification

specified in paragraph (b)(2) is accomplished

prior to the accumulation of 7,300 total

landings on the airplane.

(2) Compliance with AD 91–18–15,

amendment 39–8018, is not required if the

requirements of paragraph (b)(2) of this AD

are accomplished prior to the accumulation

of 6,000 total landings on the airplane.

(d) For all airplanes: At the applicable

times specified in paragraph (d)(1) or (d)(2),

modify the Hi-lok bolt holes at rib 5.0 of the

vertical stabilizer by cold expansion, in

accordance with Fokker Service Bulletin

SBF100–55–023, dated January 3, 1995.

(1) For airplanes that have been modified

in accordance with the requirements of

paragraph (b) of this AD prior to the effective

date of this AD: Modify prior to the

accumulation of either 10,000 landings after

in-service modification, or 10,000 landings

after delivery with factory modification, as

applicable; or within 30 days after the

effective date of this AD, whichever occurs

later.

(2) For all other airplanes: Modify

concurrent with accomplishing the

requirements of paragraph (b) of this AD.

(e) 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,

International Branch, ANM–116. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, International Branch,

ANM–116.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the International Branch,

ANM–116.

(f) 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.

(g) The actions shall be done in accordance

with the following Fokker service bulletins,

which contain the following list of effective

pages:

Referenced service bulletin and date Page No. Revision level shown

on page Date shown on page

SBF100–55–018, Revision 1, December 27,

1993.

1–4, 8–16, 18, 19, 21–23, 25–28 ..................... 1 ................................ December 27, 1993.

5–7, 17, 20, 24, 29–31 ..................................... Original ...................... May 19, 1993.

SBF100–55–019, Revision 1, May 19, 1993 ... 1–3, 5, 9, .......................................................... 1 ................................ May 19, 1993.

4, 6–8, 10–12 ................................................... Original ...................... August 11, 1992.

SBF100–55–023, January 3, 1995 ................... 1–17 .................................................................. Original ...................... January 3, 1995.

This incorporation by reference was

approved by the Director of the Federal

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

and 1 CFR part 51. Copies may be obtained

from Fokker Services B.V., Technical

Support Department, P.O. Box 75047, 1117

ZN Schiphol Airport, The Netherlands.

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.

Note 3: The subject of this AD is addressed

in Dutch airworthiness directive (BLA) 93–

069 (A), dated June 1, 1993.

(h) This amendment becomes effective on

January 2, 1998.

Issued in Renton, Washington, on

November 19, 1997.

James V. Devany,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–31029 Filed 11–26–97; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–189–AD; Amendment

39–10220; AD 97–24–13]

RIN 2120–AA64

Airworthiness Directives; British

Aerospace BAe Model ATP Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive (AD),

applicable to certain British Aerospace

BAe Model ATP airplanes, that requires

a detailed visual inspection of the flap

drive torque tubes in the wing root area

to detect inadequate clearance between

the torque tubes and surrounding

structure or scoring damage to the tubes;

and follow-on repetitive inspections or

corrective action, if necessary.

Accomplishment of certain

replacements and modifications would

constitute terminating action for the

repetitive inspections. This amendment

is prompted by reports of inadequate

clearance between flap drive torque

tubes and surrounding structures, and

possible scoring damage to the tubes.

The actions specified by this AD are

intended to prevent failure of the torque

tubes, which could result in an

asymmetric flap condition and reduced

controllability of the airplane.

DATES: Effective January 2, 1998.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of January 2,

1998.

ADDRESSES: The service information

referenced in this AD may be obtained

from AI(R) American Support, Inc.,

13850 Mclearen Road, Herndon,

Virginia 20171. 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:

International Branch, ANM–116, FAA,

Transport Airplane Directorate, 1601

Lind Avenue, SW., Renton, Washington

98055–4056; telephone (425) 227–2110;

fax (425) 227–1149.

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 British

Aerospace BAe Model ATP airplanes

was published in the Federal Register