Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules 30025

(1) Perform a detailed visual inspection of

the upper areas of the backup strut around

the welding in the pipe and in the

attachment fittings to detect any discrepancy

(including fatigue cracking or a failed backup

strut) by accomplishing all actions specified

in paragraph B.(1) of the Accomplishment

Instructions of the service bulletin, in

accordance with that service bulletin. Repeat

the detailed visual inspection thereafter at

intervals not to exceed 450 flight hours.

Note 2: For the purposes of this AD, a

detailed visual inspection is defined as: ‘‘An

intensive visual examination of a specific

structural area, system, installation, or

assembly to detect damage, failure, or

irregularity. Available lighting is normally

supplemented with a direct source of good

lighting at intensity deemed appropriate by

the inspector. Inspection aids (e.g., mirror,

magnifying lenses) may be used. Surface

cleaning and elaborate access procedures

may be required.’’

(2) Perform a dye penetrant inspection,

using Penetrant Type 1 (fluorescent dye)

sensitivity level 2, of the lower areas of the

backup strut around the welding in the pipe

and in the attachment fittings to detect any

discrepancy (including fatigue cracking or a

failed backup strut) by accomplishing all

actions specified in paragraphs B.(2) and

B.(3) of the service bulletin, as applicable, in

accordance with that service bulletin.

(i) For airplanes on which all backup struts

have accumulated less than 4,500 total flight

hours as of the effective date of this AD,

repeat the dye penetrant inspection thereafter

at intervals not to exceed 1,650 flight hours,

until any backup strut on the airplane has

accumulated 4,500 total flight hours; then

perform the repetitive inspection thereafter at

the interval specified by paragraph (b)(2)(ii)

of this AD.

(ii) For airplanes on which any backup

strut has accumulated 4,500 or more total

flight hours as of the effective date of this

AD, repeat the dye penetrant inspection

thereafter at intervals not to exceed 900 flight

hours.

Corrective Actions

(c) If any discrepancy (including fatigue

cracking, a failed backup strut, or damage to

the surrounding structure of the engine

mount) is detected during any inspection

required by this AD: Prior to further flight,

accomplish the applicable corrective actions

(including performing additional inspections

of the engine mount surrounding structure,

and replacing any discrepant backup strut in

the hydraulic or electrical bay areas with a

new backup strut) specified by paragraph C.

of the Accomplishment Instructions of Saab

Service Bulletin 2000–54–023, Revision 01,

dated January 28, 2000, in accordance with

that service bulletin. For any repair condition

for which the service bulletin specifies to

contact the manufacturer for appropriate

ACTION: Prior to further flight, repair in

accordance with a method approved by

either the Manager, International Branch,

ANM–116, FAA, Transport Airplane

Directorate; or the Luftfartsverket (LFV) (or

its delegated agent). For a repair method to

be approved by the Manager, International

Branch, ANM–116, as required by this

paragraph, the Manager’s approval letter

must specifically reference this AD.

Alternative Methods of Compliance

(d) 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 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the International Branch,

ANM–116.

Special Flight Permits

(e) 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.

Note 4: The subject of this AD is addressed

in Swedish airworthiness directive No. 1–

150R1, dated January 31, 2000.

Issued in Renton, Washington, on May 4,

2000.

Vi L. Lipski,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–11723 Filed 5–9–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–255–AD]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9–10, –20, –30, –40

and –50 Series Airplanes and C–9

(Military) Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to certain

McDonnell Douglas Model DC–9 series

airplanes and C–9 (military) airplanes,

that currently requires repetitive

ultrasonic or magnetic particle

inspections to detect cracking of the

engine pylon aft upper spar straps

(caps); and if necessary, replacement of

the strap with a new strap, or

modification of the engine pylon rear

spar straps, which constitutes

terminating action for the repetitive

inspections. This action would require

new, improved repetitive ultrasonic

inspections, and corrective actions, if

necessary. This action also would

require, among other items, a

terminating action for the repetitive

inspection requirements. This proposal

is prompted by additional reports of

fatigue cracking in the subject area on

these airplanes. The actions specified by

the proposed AD are intended to detect

and correct such fatigue cracking, which

could result in major damage to the

adjacent structure of the pylon aft spar

upper cap, and consequent reduced

structural integrity of the airplane.

DATES: Comments must be received by

June 26, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 99–NM–

255–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9:00 a.m. and 3:00

p.m., Monday through Friday, except

Federal holidays.

The service information referenced in

the proposed rule may be obtained from

Boeing Commercial Aircraft Group,

Long Beach Division, 3855 Lakewood

Boulevard, Long Beach, California

90846, Attention: Technical

Publications Business Administration,

Dept. C1-L51 (2–60). This information

may be examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington; or at

the FAA, Transport Airplane

Directorate, Los Angeles Aircraft

Certification Office, 3960 Paramount

Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Wahib Mina, Aerospace Engineer,

Airframe Branch, ANM–120L, FAA,

Transport Airplane Directorate, Los

Angeles Aircraft Certification Office,

3960 Paramount Boulevard, Lakewood,

California 90712–4137; telephone (562)

627–5324; fax (562) 627–5210.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to

participate in the making of the

proposed rule by submitting such

written data, views, or arguments as

they may desire. Communications shall

identify the Rules Docket number and

be submitted in triplicate to the address

specified above. All communications

received on or before the closing date

for comments, specified above, will be

considered before taking action on the

proposed rule. The proposals contained

30026 Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules

in this notice may be changed in light

of the comments received.

Comments are specifically invited on

the overall regulatory, economic,

environmental, and energy aspects of

the proposed rule. All comments

submitted will be available, both before

and after the closing date for comments,

in the Rules Docket for examination by

interested persons. A report

summarizing each FAA-public contact

concerned with the substance of this

proposal will be filed in the Rules

Docket.

Commenters wishing the FAA to

acknowledge receipt of their comments

submitted in response to this notice

must submit a self-addressed, stamped

postcard on which the following

statement is made: ‘‘Comments to

Docket Number 99–NM–255–AD.’’ The

postcard will be date stamped and

returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this

NPRM by submitting a request to the

FAA, Transport Airplane Directorate,

ANM–114, Attention: Rules Docket No.

99–NM–255–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

In 1978, the FAA issued AD 78–01–

16, amendment 39–3117, applicable to

certain McDonnell Douglas Model DC–

9 series airplanes and C–9 (military)

airplanes. That AD requires repetitive

ultrasonic or magnetic particle

inspections to detect cracking of the

engine pylon aft upper spar straps

(caps); and if necessary, replacement of

the strap with a new strap, or

modification of the engine pylon rear

spar straps (caps), which constitutes

terminating action for the repetitive

inspections. That action was prompted

by reports of fatigue cracking of the

pylon aft upper spar straps (caps). The

requirements of that AD are intended to

detect cracks and prevent failure of the

engine pylon aft upper spar straps

(caps).

Actions Since Issuance of Previous Rule

Since the issuance of AD 78–01–16,

the FAA has received additional reports

of fatigue cracking in the subject area on

these airplanes. The airplanes on which

the cracking occurred had accumulated

between 19,000 and 36,000 landings.

Investigation revealed that the repetitive

ultrasonic inspections, as required by

AD 78–01–16, do not adequately detect

fatigue cracking in the subject area.

Such fatigue cracking, if not detected

and corrected, could result in major

damage to the adjacent structure of the

pylon aft spar upper cap, and

consequent reduced structural integrity

of the airplane.

Explanation of Relevant Service

Information

The FAA has reviewed and approved

McDonnell Douglas Alert Service

Bulletin DC9–54A031, Revision 08,

dated January 31, 2000, which describes

procedures for new repetitive ultrasonic

or magnetic particle inspections of the

engine pylon aft upper spar straps (caps)

to detect cracking; and corrective

actions, if necessary. The corrective

actions include reapplication of a

sealant; modification of the rear spar

upper strap (cap); and replacement of

the bearing on the spar strap (cap) with

a new annular groove bearing; as

applicable. The service bulletin

references McDonnell Douglas DC–9

Service Bulletin 54–31, Revision 4,

dated March 28, 1991, as an additional

source of service information for

accomplishment of the modification.

The FAA also has reviewed and

approved McDonnell Douglas DC–9

Service Bulletin 54–31, Revision 4,

dated March 28, 1991. The service

bulletin describes procedures for

modification of the rear spar upper strap

(cap), which would eliminate the need

for the repetitive inspections specified

in McDonnell Douglas Alert Service

Bulletin DC9–54A031, Revision 08,

dated January 31, 2000. The

modification includes installation of

access doors on the pylon rear spars, if

applicable; replacement of the strap on

the pylon upper rear spar cap with a

new strap using new close tolerance

attaching parts; and modification of the

pylon-to-vibration isolator link.

Accomplishment of the actions

specified in the service bulletins is

intended to adequately address the

identified unsafe condition.

Explanation of Requirements of

Proposed Rule

Since an unsafe condition has been

identified that is likely to exist or

develop on other products of this same

type design, the proposed AD would

supersede AD 78–01–16 to continue to

require repetitive ultrasonic or magnetic

particle inspections to detect cracking of

the engine pylon aft upper spar straps

(caps); and if necessary, replacement of

the strap with a new strap, or

modification of the engine pylon rear

spar straps (caps), which constitutes

terminating action for the repetitive

inspections. The proposed AD also

would require accomplishment of the

actions specified in the service bulletins

described previously.

Cost Impact

There are approximately 809 Model

DC–9–10, –20, –30, –40 and –50 series

airplanes and C–9 (military) airplanes of

the affected design in the worldwide

fleet. The FAA estimates that 572

airplanes of U.S. registry would be

affected by this proposed AD.

The ultrasonic inspection that is

currently required by AD 78–01–16, and

retained in this proposed AD, takes

approximately 3 work hours, per

airplane to accomplish, at an average

labor rate of $60 per work hour. Based

on these figures, the cost impact of the

currently required actions on U.S.

operators is estimated to be $180 per

airplane, per inspection cycle.

The new ultrasonic inspection that is

proposed in this AD action would take

approximately 4 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 ultrasonic inspection proposed by

this AD on U.S. operators is estimated

to be $240 per airplane, per inspection

cycle.

The new modification of the rear spar

upper strap (cap) that is proposed in

this AD action would take between

approximately 349 and 412 work hours

depending on the configuration of the

affected airplane to accomplish, at an

average labor rate of $60 per work hour.

The cost of required parts would be

between approximately $1,865 and

$7,947 per airplane. Based on these

figures, the cost impact of the new

modification proposed by this AD on

U.S. operators is estimated to be

between $22,805 and $32,667 per

airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the current or proposed 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 magnetic

particle inspection that would be

provided by this AD action, it would

take approximately 7 work hours to

accomplish it, at an average labor rate of

$60 per work hour. Based on these

figures, the cost impact of this action

would be $420 per airplane, per

inspection cycle.

Regulatory Impact

The regulations proposed herein

would 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

Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules 30027

various levels of government. Therefore,

it is determined that this proposal

would not have federalism implications

under Executive Order 13132.

For the reasons discussed above, I

certify that this proposed regulation (1)

is not a ‘‘significant regulatory action’’

under Executive Order 12866; (2) is not

a ‘‘significant rule’’ under the DOT

Regulatory Policies and Procedures (44

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

promulgated, 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 copy of the draft

regulatory evaluation prepared for this

action is contained in the Rules Docket.

A copy of it may be obtained by

contacting the Rules Docket at the

location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration proposes to amend 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 39–3117, and by

adding a new airworthiness directive

(AD), to read as follows:

McDonnell Douglas: Docket 99–NM–255–

AD. Supersedes AD 78–01–16,

Amendment 39–3117.

Applicability: Model DC–9–10, –20, –30,

–40, and –50 series airplanes, and C–9

(military) airplanes, fuselage numbers 1

through 851, 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 (p) 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 pylon aft upper spar straps (caps), which

could result in major damage to the adjacent

structure of the pylon aft spar upper cap, and

consequent reduced structural integrity of the

airplane, accomplish the following:

Restatement of Requirements of AD 78–01–

16, Amendment 39–3117

Compliance Times

(a) For airplanes that have accumulated

35,000 or more total landings as of February

13, 1978 (the effective date of AD 78–01–16,

amendment 39–3117): Within 600 landings

after February 13, 1978, unless already

accomplished within the last 1,800 landings,

and thereafter at intervals not to exceed 2,400

landings, accomplish the actions specified in

paragraph (f) of this AD.

(b) For airplanes that have accumulated

between 30,000 and 34,999 total landings

inclusive, as of February 13, 1978: Within

900 landings after February 13, 1978, unless

already accomplished within the last 1,500

landings, and thereafter at intervals not to

exceed 2,400 landings, accomplish the

actions specified in paragraph (f) of this AD.

(c) For airplanes that have accumulated

between 25,000 and 29,999 total landings

inclusive, as of February 13, 1978: Within

1,200 landings after February 13, 1978,

unless already accomplished within the last

1,200 landings, and thereafter at intervals not

to exceed 2,400 landings, accomplish the

actions specified in paragraph (f) of this AD.

(d) For airplanes that have accumulated

between 15,000 and 24,999 total landings

inclusive, as of February 13, 1978: Within

2,000 landings after February 13, 1978,

unless already accomplished within the last

400 landings, and thereafter at intervals not

to exceed 2,400 landings, accomplish the

actions specified in paragraph (f) of this AD.

(e) For airplanes that have accumulated

less than 15,000 total landings as of February

13, 1978: Within 2,000 landings after the

accumulation of 15,000 total landings, and

thereafter at intervals not to exceed 2,400

landings, accomplish the actions specified in

paragraph (f) of this AD.

Repetitive Inspections and Corrective Actions

(f) At the times specified in paragraphs (a)

through (e), except as provided by paragraph

(g) of this AD, perform an ultrasonic

inspection of the engine pylon aft upper spar

straps (caps), part number (P/N) 9958154–5/

–6, or P/N 9958154–37/–38, to detect

cracking, in accordance with paragraph 2.B

of McDonnell Douglas DC–9 Service Bulletin

A54–31, dated December 22, 1976, or in

accordance with a method approved by the

Manager, Los Angeles Aircraft Certification

Office (ACO), FAA, Transport Airplane

Directorate.

Note 2: Alternative methods of compliance

approved previously prior to the effective

date of this AD in accordance with the Chief,

Aircraft Engineering Division, Western

Region, are considered acceptable for

compliance with paragraph (f) of this AD.

(1) If there is evidence of cracking, the

magnetic particle inspection specified in

paragraph 2.C of the service bulletin may be

used to confirm the evidence of cracking.

(2) If any cracking is detected, prior to

further flight, accomplish either paragraph

(f)(2)(i) or (f)(2)(ii) of this AD in accordance

with the service bulletin.

(i) Replace the strap with a new strap, P/

N 9958154–5/–6, or P/N 9958154–37/–38,

and repeat the inspection thereafter at

intervals not to exceed 15,000 landings. Or

(ii) Modify the engine pylon rear spar

straps (caps) in accordance with the service

bulletin. Accomplishment of the

modification constitutes terminating action

for the repetitive inspection requirements of

this AD.

Note 3: Modification of the engine pylon

rear spar straps (caps) accomplished prior to

the effective date of this AD in accordance

with McDonnell Douglas DC–9 Alert Service

Bulletin A54–31, Revision 2, dated December

22, 1977; Revision 3, dated June 20, 1986;

Revision 4, dated March 26, 1987; Revision

5, dated March 25, 1991; or Revision 6, dated

November 23, 1992; is considered acceptable

for compliance with the requirements of

paragraph (f)(2)(ii) of this AD.

Optional Magnetic Particle Inspection

(g) In lieu of accomplishing the ultrasonic

inspection, at the times specified in

paragraphs (a) through (e) of this AD, perform

a magnetic particle inspection of the engine

pylon aft upper spar straps (caps), P/N

9958154–5/–6, or P/N 9958154–37/–38, to

detect cracking, in accordance with

paragraph 2.C of McDonnell Douglas DC–9

Service Bulletin A54–31, dated December 22,

1976. If any cracking is detected, prior to

further flight, accomplish the action specified

in paragraph (f) of this AD. After two bearing

replacements, accomplish the action

specified in either paragraph (f)(2)(i) or

(f)(2)(ii) of this AD.

Note 4: Ultrasonic or magnetic particle

inspection of the engine pylon aft upper spar

straps (caps) accomplished prior to the

effective date of this AD in accordance with

McDonnell Douglas DC–9 Alert Service

Bulletin A54–31, Revision 2, dated December

22, 1977; Revision 3, dated June 20, 1986;

Revision 4, dated March 26, 1987; Revision

5, dated March 25, 1991; or Revision 6, dated

November 23, 1992; is considered acceptable

for compliance with the inspection

requirements of paragraph (f) or (g) of this

AD, as applicable.

New Requirements of This AD

Repetitive Ultrasonic Inspections

(h) For airplanes on which the

modification/replacement specified in

paragraph (f)(2)(ii) or (n) of this AD has not

been accomplished, and on which the

replacement specified in paragraph (f)(2)(i) of

this AD has not been accomplished: Except

as provided by paragraph (m) of this AD,

perform an ultrasonic inspection of the

engine pylon aft upper spar straps (caps) to

detect cracking, in accordance with

McDonnell Douglas Alert Service Bulletin

DC9–54A031, Revision 08, dated January 31,

2000; at the time specified in paragraph

30028 Federal Register / Vol. 65, No. 91 / Wednesday, May 10, 2000 / Proposed Rules

(h)(1), (h)(2), (h)(3), or (h)(4) of this AD, as

applicable. Repeat this inspection thereafter

at intervals not to exceed 2,400 landings.

Accomplishment of the ultrasonic

inspection constitutes terminating action for

the repetitive inspection requirements of

paragraphs (a) through (f), (f)(2)(i), and (g) of

this AD.

(1) For airplanes that have accumulated

between 15,000 and 24,999 total landings as

of the effective date of this AD: Within 2,000

landings or 6 months after the effective date

of this AD, whichever occurs later.

(2) For airplanes that have accumulated

between 25,000 and 29,999 total landings as

of the effective date of this AD: Within 1,200

landings or 6 months after the effective date

of this AD, whichever occurs later.

(3) For airplanes that have accumulated

between 30,000 and 34,999 total landings as

of the effective date of this AD: Within 900

landings or 6 months after the effective date

of this AD, whichever occurs later.

(4) For airplanes that have accumulated

35,000 or more total landings as of the

effective date of this AD: Within 600 landings

or 6 months after the effective date of this

AD, whichever occurs later.

(i) For airplanes on which the

modification/replacement specified in

paragraph (f)(2)(ii) or (n) of this AD has not

been accomplished, and on which the

replacement specified in paragraph (f)(2)(i) of

this AD has been accomplished: Except as

provided by paragraph (m) of this AD,

perform an ultrasonic inspection of the

engine pylon aft upper spar straps (caps) to

detect cracking, in accordance with

McDonnell Douglas Alert Service Bulletin

DC9–54A031, Revision 08, dated January 31,

2000; at the time specified in paragraph (i)(1),

(i)(2), (i)(3), or (i)(4) of this AD, as applicable.

Repeat this inspection thereafter at intervals

not to exceed 2,400 landings.

(1) For airplanes that have accumulated

between 15,000 and 24,999 landings since

installation of the new spar strap (cap):

Within 2,000 landings or 6 months after the

effective date of this AD, whichever occurs

later.

(2) For airplanes that have accumulated

between 25,000 and 29,999 landings since

installation of the new spar strap (cap):

Within 1,200 landings or 6 months after the

effective date of this AD, whichever occurs

later.

(3) For airplanes that have accumulated

between 30,000 and 34,999 landings since

installation of the new spar strap (cap):

Within 900 landings or 6 months after the

effective date of this AD, whichever occurs

later.

(4) For airplanes that have accumulated

35,000 or more landings since installation of

the new spar strap (cap): Within 600 landings

or 6 months after the effective date of this

AD, whichever occurs later.

(j) If no cracking is detected during any

inspection required by paragraph (h), (i), or

(m) of this AD, prior to further flight, reapply

sealant in accordance with McDonnell

Douglas Alert Service Bulletin DC9–54A031,

Revision 08, dated January 31, 2000.

(k) If any cracking is detected during any

inspection required by paragraph (h) or (i) of

this AD, prior to further flight, accomplish

the actions specified in paragraph (m) of this

AD.

(l) If any cracking is detected during any

inspection required by paragraph (h), (i), or

(m) of this AD, prior to further flight, modify

the rear spar upper strap (cap) in accordance

with McDonnell Douglas DC–9 Service

Bulletin 54–31, Revision 4, dated March 28,

1991. Accomplishment of the modification

constitutes terminating action for the

repetitive inspection requirements of

paragraphs (h) and (i) of this AD.

(m) In lieu of accomplishing the ultrasonic

inspection required by paragraphs (h) and (i)

of this AD, at the applicable times specified

in paragraphs (h), (h)(1), (h)(2), (h)(3), (h)(4),

(i), (i)(1), (i)(2), (i)(3), or (i)(4) of this AD,

perform a magnetic particle inspection of the

engine pylon aft upper spar strap (cap) for

cracks, in accordance with McDonnell

Douglas Alert Service Bulletin DC9–54A031,

Revision 08, dated January 31, 2000. If no

cracking is detected, prior to further flight,

replace the bearing on the spar strap (cap)

with a new annular groove bearing, in

accordance with the service bulletin.

Terminating Modification

(n) Prior to the accumulation of 100,000

total landings, or within 6 months after the

effective date of this AD, whichever occurs

later, modify the rear spar upper strap (cap)

in accordance with McDonnell Douglas DC–

9 Service Bulletin 54–31, Revision 4, dated

March 28, 1991. Accomplishment of the

modification constitutes terminating action

for the repetitive inspection requirements of

paragraphs (h) and (i) of this AD.

(o) Accomplishment of the modification

required by paragraph (l) or (n) of this AD

constitutes compliance with the following:

(1) The actions specified in McDonnell

Douglas Service Bulletin 54–27, Revision 4,

dated April 2, 1990, that are required by AD

96–10–11, amendment 39–9618 (61 FR

24675, May 16, 1996) [which references

‘‘DC–9/MD80 Aging Aircraft Service Action

Requirements Document’’ (SARD),

McDonnell Douglas Report MDC K1572,

Revision B, dated January 15, 1993, as the

appropriate source of service information for

accomplishment of the modification]; and

(2) The requirements of AD 72–09–01,

amendment 39–2844 (which references

McDonnell Douglas Service Bulletin 54–31,

dated August 24, 1976, and McDonnell

Douglas Service Bulletin 54–27, Revision 4,

dated April 2, 1990, as appropriate sources

of service information for accomplishment of

the modification).

Alternative Methods of Compliance

(p) 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 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, Los Angeles ACO.

Note 5: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

Note 6: Alternative methods of compliance,

approved previously in accordance with AD

78–01–16, amendment 39–3117, are

approved as alternative methods of

compliance with this AD.

Special Flight Permits

(q) 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.

Issued in Renton, Washington, on May 3,

2000.

Vi L. Lipski,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–11722 Filed 5–9–00; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99–NM–60–AD]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–8 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

supersedure of an existing airworthiness

directive (AD), applicable to certain

McDonnell Douglas Model DC–8 series

–10 through –50, –61, –61F, –71, –71F

airplanes, that currently requires a

visual or eddy current inspection(s) of

the left and right wing front spar lower

caps to detect cracks migrating from

attachment holes; and repair, if

necessary. That AD also provided for an

optional terminating modification of the

front spar lower cap. This proposal is

prompted by a report that additional

cracking was found in the front spar

lower cap of a wing. This action would

require accomplishment of the

previously optional terminating action.

The proposed AD also would expand

the applicability of the existing AD to

include additional airplanes and to

increase the interval for the repetitive

eddy current inspections. The actions

specified by the proposed AD are

intended to prevent reduced structural

integrity of the left or right wing due to

metal fatigue failure of the front spar

lower cap.

DATES: Comments must be received by

June 26, 2000.