Federal Register / Vol. 60, No. 75 / Wednesday, April 19, 1995 / Proposed Rules 19545

of over 90 percent petroleum on an

energy equivalent basis. Reformulated

gasoline is an enumerated ‘‘clean

alternative fuel’’ in section 241 of the

Clean Air Act. 42 U.S.C. 7581. It is not

mentioned at all in the definition of

‘‘alternative fuel’’ in section 301 of the

Energy Policy Act of 1992. Section

301(2) provides as follows: the term

‘‘alternative fuel’’ means methanol,

denatured ethanol, and other alcohols;

[mixtures containing 85 percent or more

(or such other percentage, but not less

than 70 percent, as determined by the

Secretary, by rule, to provide for cold

start, safety, or vehicle functions) by

volume of methanol, denatured ethanol,

and other alcohols with gasoline, or

other fuels]; natural gas; liquefied

petroleum gas; hydrogen; coal-derived

liquid fuels; fuels (other than alcohol)

derived from biological materials;

electricity (including electricity from

solar energy); [and any other fuel the

Secretary determines, by rule, is

substantially not petroleum and would

yield substantial energy security

benefits and substantial environmental

benefits].

3. On page 10973, third column, first

full paragraph following paragraph 4.,

the first sentence is corrected to read as

follows:

Each of the above bracketed phrases

sets forth limited authority for the

Department to add fuels to the

definition of ‘‘alternative fuel.’’

4. On page 10990, second column, in

Appendix A To Subpart A of Part 490,

‘‘Metropolitan Statistical Areas/

Consolidated Metropolitan Statistical

Areas with 1980 Populations of 250,000

or more,’’ add the following

Metropolitan Statistical Areas in

alphabetical order:

Duluth MSA MN–WI

Johnstown MSA PA

Kalamazoo-Battle Creek MSA MI

Thomas J. Gross,

Deputy Assistant Secretary for Transportation

Technologies, Office of Energy Efficiency and

Renewable Energy.

[FR Doc. 95–9693 Filed 4–18–95; 8:45 am]

BILLING CODE 6450–01–M

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94–NM–167–AD]

Airworthiness Directives; Mitsubishi

Model YS–11 and –11A Series

Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to

Mitsubishi Model YS–11 and –11A

series airplanes. This proposal would

require the implementation of a

corrosion prevention and control

program. This proposal is prompted by

incidents involving corrosion and

fatigue cracking in transport category

airplanes that are approaching or have

exceeded their economic design goal;

these incidents have jeopardized the

airworthiness of the affected airplanes.

The actions specified by the proposed

AD are intended to prevent degradation

of the structural capabilities of the

affected airplanes due to problems

associated with corrosion.

DATES: Comments must be received by

May 25, 1995.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 94–NM–

167–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

Nihon Aeroplane Manufacturing,

Toranomon Daiichi, Kotohire-Cho,

Shiba, Minato-Ku, Tokyo, Japan. This

information may be examined at the

FAA, Transport Airplane Directorate,

1601 Lind Avenue SW., Renton,

Washington; or at the FAA, Los Angeles

Aircraft Certification Office, Transport

Airplane Directorate, 3960 Paramount

Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

William Roberts, Aerospace Engineer,

Airframe Branch, ANM–120L, Los

Angeles Aircraft Certification Office,

FAA, Transport Airplane Directorate,

3960 Paramount Boulevard, Lakewood,

California 90712–4137; telephone (310)

627–5228; fax (310) 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

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 94–NM–167–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–103, Attention: Rules Docket No.

94–NM–167–AD, 1601 Lind Avenue

SW., Renton, Washington 98055–4056.

Discussion

In April 1988, a transport category

airplane managed to land after tiny

cracks in rivet holes in the upper

fuselage linked together, causing

structural failure and explosive

decompression. An 18-foot section

ripped from the fuselage. This accident

focused greater attention on the problem

of aging aircraft.

In June 1988, the FAA sponsored an

international conference on aging

airplane issues, which was attended by

representatives of the aviation industry

from around the world. It became

obvious that, because of the tremendous

increase in air travel, the relatively slow

pace of new airplane production, and

the apparent economic feasibility of

operating older technology airplanes

rather than retiring them, increased

attention needed to be focused on the

aging fleets and maintaining their

continued operational safety.

In concert with the objectives that

arose from this conference, the ‘‘YS–11

Structures Working Group (SWG),’’ was

formed in 1990. This group was

comprised of representatives of several

Japanese airlines and overhaul facilities;

Mitsubishi Heavy Industries (MHI), the

airframe manufacturer; and the Japan

Civil Aviation Bureau (JCAB), which is

the airworthiness authority for Japan. It

undertook the task of identifying and
19546 Federal Register / Vol. 60, No. 75 / Wednesday, April 19, 1995 / Proposed Rules

implementing procedures to ensure the

continuing structural airworthiness of

Model YS–11 fleet.

As a result of this group’s effort, a

baseline program was developed for

controlling corrosion problems that may

jeopardize the continued airworthiness

of the Model YS–11 fleet. The program

is contained in MHI Publication No.

YS–MR–301, ‘‘YS–11 Corrosion Control

Program,’’ dated November 1, 1993

(hereafter referred to as ‘‘the

Document’’).

The JCAB has classified the Document

as mandatory, and has issued Japanese

Airworthiness Directive TCF–50–001–

1E–1, KU–KI–1532, TCD–3954–93,

dated December 27, 1993, addressing

this subject.

Section 1.2 of the Document describes

the basic requirements of the corrosion

control program (CCP).

Section 1.3 of the Document defines

three levels of corrosion: Level 1

corrosion is that which does not exceed

certain limits; Level 2 corrosion is that

which exceeds those limits; and Level 3

corrosion is significant corrosion which

is potentially an urgent airworthiness

concern.

Section 2 of the Document describes

the general guidelines for developing

and implementing a corrosion

prevention and control program. These

guidelines address such things as the

scope and priority of the baseline

program; the relationship between an

operator’s maintenance program and the

CCP; intervals for accomplishment of

the basic tasks for corrosion prevention;

selection of corrosion preventive

compound; and how the program relates

to newly-acquired, leased, and

transferred airplanes. This section also

provides for periodic review and update

of the data contained in the Document.

It should be noted that this section

indicates that, since more than 20 years

have passed since most Model YS–11

airplanes were last manufactured,

implementation of the Baseline Program

is necessary for all airplanes. In light of

this, the program described in the

Document does not specify any

particular ‘‘implementation age’’ for

initiating the program on a particular

airplane. Instead, it emphasizes

developing and adopting a program,

then accomplishing the specific actions

on each airplane in an operator’s fleet,

on a phased-in basis.

Section 3 of the Document establishes

the procedures for reporting the results

of the inspections conducted under the

program. It describes the specific system

for reporting of findings when various

levels of corrosion are determined to

exist.

Section 4 of the Document lays out

the recommended baseline program.

This section describes the ‘‘basic task’’

to be accomplished in each defined

airplane area (‘‘zone’’) as part of the

baseline program, the specific airplane

areas that are subject to the program,

and the intervals for inspecting areas

and applying corrosion preventive

compound. A ‘‘basic task’’ includes

visual inspections of all primary and

secondary structures, and may also

include detailed visual and nondestructive inspections (NDI). Any

corrosion or other damage found as a

result of these inspections must be

repaired.

This airplane model is manufactured

in Japan and is type certificated for

operation in the United States under the

provisions of § 21.29 of the Federal

Aviation Regulations (14 CFR 21.29)

and the applicable bilateral

airworthiness agreement. Pursuant to

this bilateral airworthiness agreement,

the JCAB has kept the FAA informed of

the situation described above. The FAA

has examined the findings of the JCAB,

reviewed all available information, and

determined that AD action is necessary

for products of this type design that are

certificated for operation in the United

States.

Since corrosion is likely to exist or

develop on airplanes of this type design,

an AD is proposed which would require

adoption of a corrosion prevention and

control program that is equivalent to or

better than the program specified in the

Document previously described.

Operators would be permitted to

accomplish this either by performing

the specific basic tasks described in the

Document (the ‘‘task-by-task method), or

by revising their FAA-approved

maintenance program to include such a

program.

Paragraph (a) of the proposal sets

forth the proposed compliance time for

the implementation of the schedule for

accomplishing the basic task for each

affected aircraft area. The basic task

would be required to be repeated at a

time interval not to exceed the repeat

interval for that area, as detailed in the

Document.

Operators should note that the

proposal does not contain a paragraph

specifically to address repair actions.

The FAA considers that any repairs

would be carried out necessarily as a

part of each basic task, as it is defined

in the Document. As discussed

previously, a ‘‘basic task’’ is defined in

the Document as including not only the

pertinent inspection, but any necessary

repairs, application of corrosion

inhibitors, and other follow-on

procedures, as well. Paragraph (a)

contains a note to reference the portion

of the Document that defines a basic

task, and to emphasize the importance

of these corrective actions.

Paragraph (b) of the proposal provides

for an optional method of complying

with the rule. In lieu of performing the

task-by-task requirements proposed in

paragraph (a), operators may revise their

FAA-approved maintenance/inspection

programs to include the corrosion

prevention and control program defined

in the Document or an equivalent

program approved by the FAA.

Paragraph (b) also would require that,

subsequent to the accomplishment of

the initial basic task, any extensions of

repeat intervals specified in the

Document must be approved by the

FAA.

Any operator electing to comply with

proposed paragraph (b) would be

permitted to use an alternative

recordkeeping method to that otherwise

required by Federal Aviation

Regulations (FAR) § 91.417 or § 121.380,

provided it is approved by the FAA and

is included in a revision to the FAAapproved maintenance/inspection

program. In response to questions raised

previously concerning recordkeeping

and record retention requirements as

they relate to the programmatic

approach proposed in this AD action

and other similar proposals that have

been issued applicable to other airplane

models, the FAA offers the following:

Sections 91.417(a)(2)(v) and

121.380(a)(2)(v) of the FAR require that

a record be made of the current status

of applicable AD’s. With regard to

proposed paragraph (b), such a record

would be required to be made when the

maintenance/inspection program is

revised to incorporate the program

specified in the Document; at that time,

paragraph (b) of the AD would be fully

complied with. Regarding paragraphs

(d) through (g) of this proposal, those

paragraphs would impose separate

requirements; therefore, except as

discussed below, separate entries would

have to be made to reflect compliance

with each of those paragraphs.

Section 121.380(a)(2)(iv) of the FAR

concerns recording ‘‘the identification

of the current inspection status of the

aircraft.’’ Section 91.417(a)(2)(iv)

contains a similar requirement. Because

proposed paragraph (b) would require

operators to revise their maintenance/

inspection program to include the

program specified in the Document,

each operator’s program would require

a record of each inspection to be

performed. By recording the current

inspection status of each airplane, and

by maintaining a cross-reference system

between these records and the
Federal Register / Vol. 60, No. 75 / Wednesday, April 19, 1995 / Proposed Rules 19547

maintenance/inspection program

revision, it will be possible to determine

the current status of each basic task on

each airplane. Once this cross-reference

system has been established (normally

within a year after the effective date of

the AD), this recording provision of

Sections 91 and 121 requires no

additional recording beyond what

would otherwise be required normally.

Section 121.380(a)(1) concerns

‘‘records necessary to show that all

requirements for the issuance of an

airworthiness release under Section

121.709 have been met.’’ Section

91.417(a)(1) contains a similar

requirement. These are also referred to

as ‘‘dirty fingerprint records.’’ This

provision of Sections 91 and 121

requires most of the recording that

would result from this proposed AD.

Each time a basic task is performed, the

operator would be required to make a

‘‘dirty fingerprint’’ record of the task,

identifying what actions were

accomplished. It should be noted,

however, that these records are not

different from the records made for any

other actions taken under the operator’s

maintenance/inspection program.

In addition to the record making

requirements, discussed above, Sections

91 and 121 of the FAR impose

requirements for record retention:

Section 121.380(b)(1) and Section

91.417(b)(1) require that the ‘‘dirty

fingerprint’’ records be retained until

the work is repeated or superseded by

other work, or for one year after the

work is performed. Therefore, most of

the records resulting from this proposed

AD would not have to be retained

indefinitely. However, such retention

might facilitate subsequent transfers, or

substantiate requests for repetitive

interval escalations, and therefore, may

be in the operator’s interest.

Section 121.380(b)(2) requires that the

records specified in paragraph

121.380(a)(2) [current status of AD’s and

current inspection status] be retained

and transferred with the airplane at the

time it is sold. Section 91.417(b)(2)

contains a similar requirement.

These recording requirements are not

considered to be unduly burdensome

and are considered the minimum

necessary to enable the cognizant FAA

Maintenance Inspector to perform

proper surveillance and to ensure that

the objectives of the proposed rule are

being fulfilled.

Due to numerous concerns expressed

previously by operators regarding the

recordkeeping obligations imposed by

Section 121.380 with regard to similar

rulemaking on corrosion prevention and

control programs, the FAA has included

in this proposal certain provisions for

alternative recordkeeping methods.

Proposed paragraph (b)(1) would

provide for the development and

implementation of such alternative

methods, which must be approved by

the FAA. For example, operators may

choose to submit proposals to record

compliance with paragraphs (d) through

(g) of the AD by a means other than they

normally use to record AD status. [The

FAA has developed guidance material

that will contain information to be

considered by FAA Principal

Maintenance Inspectors (PMI) when

reviewing proposals for alternative

recordkeeping methods.]

Paragraph (c) of the proposal provides

for increasing a repeat interval by up to

10% in order to accommodate

unanticipated scheduling requirements.

Operators would be required to inform

the FAA within 30 days of such

increases.

Paragraph (d)(1) of the proposal sets

forth the reporting actions that are

necessary to be accomplished when

Level 3 corrosion is determined to exist.

Within 7 days after such a

determination is made, an operator

would be required to accomplish one of

the following actions:

1. Submit a report of the

determination to the FAA and complete

the basic task in the affected area on the

remainder of the Model YS–11/–11A

series airplanes in the operator’s fleet; or

2. Submit a proposed schedule, for

approval by the FAA, for performing the

basic tasks in the affected area on the

remainder of the operator’s Model YS–

11/–11A series fleet; or

3. Submit data substantiating that the

Level 3 corrosion was an isolated

occurrence.

Once the FAA has received such a

report, it may, in conjunction with

normal surveillance activities, request

additional information regarding the

results of the basic tasks performed on

the remainder of the operator’s Model

YS–11/–11A series fleet.

Paragraph (d)(2) of the proposal

specifies that the FAA may impose

schedules different from what an

operator has proposed under paragraph

(d)(1), if it is found that changes are

necessary to ensure that any other Level

3 corrosion in the operator’s Model

YS–11 series fleet is detected in a timely

manner.

Paragraph (d)(3) of the proposal

would require that, within the time

schedule approved by the FAA, the

operator must accomplish the basic

tasks in the affected areas on the

remaining airplanes in its Model YS–11/

–11A series fleet to ensure that any

other Level 3 corrosion is detected and

repaired.

Paragraph (e) would require that,

upon finding corrosion exceeding Level

1 during a repetitive inspection, an

operator must adjust its program to

ensure that future corrosion findings are

limited to Level 1 or better. Where

corrective action is necessary to reduce

corrosion to Level 1 or better, an

operator must submit a proposal for

corrective action for the FAA’s approval

within 60 days after the determination

of corrosion is made. That action,

approved by the FAA, must then be

implemented to reduce future findings

of corrosion in that area to Level 1 or

better.

With regard to paragraph (e), it should

be noted that if corrosion is found and

it is not considered representative of the

operator’s fleet, no further corrective

action may be necessary, since a means

to reduce any corrosion to Level 1 or

better will have already been

implemented in the operator’s program

in accordance with proposed paragraph

(a) or (b). For example, if a finding of

corrosion is attributable to a particular

spill of mercury or other unique event,

or if corrosion is found on an airplane

recently acquired from another operator,

the means specified in the existing

program may be adequate for controlling

corrosion in the remainder of the

operator’s fleet. Similarly, if an operator

has already implemented means to

reduce corrosion in an airplane area

based on previous findings, no

additional corrective action may be

necessary. In reviewing the reports

submitted in accordance with the AD,

the FAA will monitor the effectiveness

of the corrective action to reduce

corrosion. If the FAA determines that an

operator has failed to implement

adequate means to reduce corrosion to

Level 1 or better, appropriate action will

be taken to ensure compliance with this

paragraph.

Paragraph (f) of the proposal concerns

adding airplanes to an operator’s fleet,

and the procedures that must be

followed with regard to corrosion

prevention and control. This paragraph

differentiates between procedures

applicable to added airplanes that

previously were maintained in

accordance with this AD and those that

were not so maintained. For airplanes

that previously have been maintained in

accordance with the proposed

requirements of this AD action, the first

basic task in each aircraft area to be

performed by the new operator would

be required to be performed in

accordance with either the previous

operator’s or the new operator’s

inspection schedule, whichever would

result in the earlier accomplishment

date for that task. For airplanes that
19548 Federal Register / Vol. 60, No. 75 / Wednesday, April 19, 1995 / Proposed Rules

have not been maintained in accordance

with the proposed requirements of this

AD action, the first basic task in each

aircraft area to be performed by the new

operator would be required to be

performed before the airplane is placed

in service, or in accordance with a

schedule approved by the FAA.

With regard to the requirements of

paragraph (f), the FAA considers it

essential that operators ensure that

transferred airplanes are inspected in

accordance with the baseline corrosion

prevention and control program on the

same basis as if there were continuity in

ownership. Scheduling of the

inspections for each airplane must not

be delayed or postponed due to a

transfer of ownership. The proposed

rule would require that the specified

procedures be accomplished before any

operator places into service any airplane

subject to the requirements of the

proposed AD.

Paragraph (g) of the proposal would

require that reports of Level 2 and Level

3 corrosion be submitted to Mitsubishi

within certain time periods after such

corrosion is detected. A note has been

included in this paragraph indicating

that reporting to the FAA of any Level

2 or Level 3 corrosion found as a result

of any opportunity inspections is highly

desirable. Operators are not relieved,

however, from reporting corrosion

findings as required by FAR § 121.703.

Cost Impact

The FAA estimates that 39 airplanes

of U.S. registry would be affected by this

proposed AD, that it would take

approximately 8 work hours per basic

task to accomplish the 30 basic tasks

called out in the Document; this

represents a total average of 240 work

hours (this figure includes not only

inspection time, but access and closure

time as well).

The average labor rate is $60 per work

hour. Based on these figures, the total

cost impact of the proposed AD on U.S.

operators for the 4-year average

inspection cycle is estimated to be

$561,600, or $14,400 per airplane.

The total cost impact figure discussed

above is based on assumptions that no

operator has yet accomplished any of

the proposed requirements of this AD

action, and that no operator would

accomplish those actions in the future if

this AD were not adopted.

The FAA recognizes that the

obligation to maintain aircraft in an

airworthy condition is vital, but

sometimes expensive. Because AD’s

require specific actions to address

specific unsafe conditions, they appear

to impose costs that would not

otherwise be borne by operators.

However, because of the general

obligation of operators to maintain

aircraft in an airworthy condition, this

appearance is deceptive. Attributing

those costs solely to the issuance of this

AD is unrealistic because, in the interest

of maintaining safe aircraft, prudent

operators would accomplish the

required actions even if they were not

required to do so by the AD.

A full cost-benefit analysis has not

been accomplished for this proposed

AD. As a matter of law, in order to be

airworthy, an aircraft must conform to

its type design and be in a condition for

safe operation. The type design is

approved only after the FAA makes a

determination that it complies with all

applicable airworthiness requirements.

In adopting and maintaining those

requirements, the FAA has already

made the determination that they

establish a level of safety that is costbeneficial. When the FAA, as in this

proposed AD, makes a finding of an

unsafe condition, this means that the

original cost-beneficial level of safety is

no longer being achieved and that the

proposed actions are necessary to

restore that level of safety. Because this

level of safety has already been

determined to be cost-beneficial, a full

cost-benefit analysis for this proposed

AD would be redundant and

unnecessary.

Regulatory Impact

The regulations proposed herein

would 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

proposal would not have sufficient

federalism implications to warrant the

preparation of a Federalism Assessment.

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. App. 1354(a), 1421

and 1423; 49 U.S.C. 106(g); and 14 CFR

11.89.

§ 39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

Mitsubishi Heavy Industries, Ltd.: Docket

94–NM–167–AD.

Applicability: All Model YS–11 and –11A

series airplanes, certificated in any category.

Note 1: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

modified, altered, or repaired in the area

subject to the requirements of this AD. For

airplanes that have been modified, altered, or

repaired so that the performance of the

requirements of this AD is affected, the

owner/operator must use the authority

provided in paragraph (h) to request approval

from the FAA. This approval may address

either no action, if the current configuration

eliminates the unsafe condition; or different

actions necessary to address the unsafe

condition described in this AD. Such a

request should include an assessment of the

effect of the changed configuration on the

unsafe condition addressed by this AD. In no

case does the presence of any modification,

alteration, or repair remove any airplane from

the applicability of this AD.

Compliance: Required as indicated, unless

accomplished previously.

Note 2: This AD references MHI

Publication No. YS–MR–301, ‘‘YS–11

Corrosion Control Program,’’ dated November

1, 1993 (hereafter referred to as ‘‘the

Document’’), for basic tasks, definitions of

corrosion levels, compliance times, and

reporting requirements. In addition, this AD

specifies inspection and reporting

requirements beyond those included in the

Document. Where there are differences

between the AD and the Document, the AD

prevails.

Note 3: As used throughout this AD, the

term ‘‘the FAA’’ is defined differently for

different operators, as follows: For those

operators complying with paragraph (a) of

this AD, ‘‘the FAA’’ is defined as ‘‘the

Manager of the Los Angeles Aircraft

Certification Office (ACO).’’ For those

operators operating under Federal Aviation
Federal Register / Vol. 60, No. 75 / Wednesday, April 19, 1995 / Proposed Rules 19549

Regulation (FAR) Part 121 or 129, and

complying with paragraph (b) of this AD,

‘‘the FAA’’ is defined as ‘‘the cognizant

Principal Maintenance Inspector (PMI).’’ For

those operators operating under FAR Part 91

or 125, and complying with paragraph (b) of

this AD, ‘‘the FAA’’ is defined as ‘‘the

cognizant Maintenance Inspector at the

appropriate FAA Flight Standards office.’’

To preclude degradation of the structural

capabilities of the airplane due to the

problems associated with corrosion,

accomplish the following:

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

this AD, within a date two years after the

effective date of this AD, complete each of

the basic tasks specified in Section 4.3 of the

Document in accordance with the procedures

specified in the Document and the schedule

specified in Figure 5 of the Document.

Thereafter, repeat each basic task at a time

interval not to exceed the repeat interval

specified in Section 4 of the Document for

that task.

Note 4: A ‘‘basic task,’’ as defined in

Section 4 of the Document, includes

inspections; procedures for a corrective

action, including repairs, under identified

circumstances; application of sealants or

corrosion inhibitors; and other follow-on

actions.

Note 5: Basic tasks completed in

accordance with the Document before the

effective date of this AD may be credited for

compliance with the initial basic task

requirements of this paragraph.

Note 6: Where non-destructive inspection

(NDI) methods are employed, in accordance

with Section 4 of the Document, the

standards and procedures used must be

acceptable to the Administrator in

accordance with FAR Section 43.13.

(b) As an alternative to the requirements of

paragraph (a) of this AD: Within one year

after the effective date of this AD, revise the

FAA-approved maintenance/inspection

program to include the corrosion control

program specified in the Document; or to

include an equivalent program that is

approved by the FAA.

(1) Any operator complying with paragraph

(b) of this AD may use an alternative

recordkeeping method to that otherwise

required by FAR § 91.417 or § 121.380 for the

actions required by this AD, provided it is

approved by the FAA and is included in a

revision to the FAA-approved maintenance/

inspection program.

(2) Subsequent to the accomplishment of

the initial basic task, any extensions of repeat

intervals specified in the Document must be

approved by the FAA.

(c) To accommodate unanticipated

scheduling requirements, it is acceptable for

a repeat interval to be increased by up to

10%, but not to exceed 6 months. The FAA

must be informed, in writing, of any such

extension within 30 days after such

adjustment of the schedule.

(d)(1) If, as a result of any inspection

conducted in accordance with paragraphs (a)

or (b) of this AD, Level 3 corrosion is

determined to exist in any airplane area,

accomplish either paragraph (d)(1)(i) or

(d)(1)(ii) within 7 days after such

determination:

(i) Submit a report of that determination to

the FAA and complete the basic task in the

affected aircraft zones on all Model YS–11/

–11A series airplanes in the operator’s fleet;

or

(ii) Submit to the FAA for approval one of

the following:

(A) A proposed schedule for performing

the basic tasks in the affected aircraft zones

on the remaining Model YS–11/–11A series

airplanes in the operator’s fleet, which is

adequate to ensure that any other Level 3

corrosion is detected in a timely manner,

along with substantiating data for that

schedule; or

(B) Data substantiating that the Level 3

corrosion found is an isolated occurrence.

Note 7: Notwithstanding the provisions of

section 1.3 of the Document, which would

permit corrosion that otherwise meets the

definition of Level 3 corrosion (i.e., which is

determined to be a potentially urgent

airworthiness concern requiring expeditious

action) to be treated as Level 1 if the operator

finds that it ‘‘can be attributed to an event not

typical of the operator’s usage of other

airplanes in the same fleet,’’ this paragraph

requires that data substantiating any such

finding be submitted to the FAA for

approval.

(2) The FAA may impose schedules other

than those proposed, upon finding that such

changes are necessary to ensure that any

other Level 3 corrosion is detected in a

timely manner.

(3) Within the time schedule approved

under paragraph (d)(1) or (d)(2) of this AD,

accomplish the basic tasks in the affected

aircraft zones of the remaining Model YS–11/

–11A series airplanes in the operator’s fleet.

(e) If, as a result of any inspection after the

initial inspection conducted in accordance

with paragraphs (a) or (b) of this AD, it is

determined that corrosion findings exceed

Level 1 in any area, within 60 days after such

determination, implement a means, approved

by the FAA, to reduce future findings of

corrosion in that area to Level 1 or better.

(f) Before any operator places into service

any airplane subject to the requirements of

this AD, a schedule for the accomplishment

of basic tasks required by this AD must be

established in accordance with paragraph

(f)(1) or (f)(2) of this AD, as applicable:

(1) For airplanes previously maintained in

accordance with this AD, the first basic task

in each aircraft zone to be performed by the

new operator must be accomplished in

accordance with the previous operator’s

schedule or with the new operator’s

schedule, whichever would result in the

earlier accomplishment date for that task.

After each basic task has been performed

once, each subsequent task must be

performed in accordance with the new

operator’s schedule.

(2) For airplanes that have not been

previously maintained in accordance with

this AD, the first basic task for each aircraft

zone to be performed by the new operator

must be accomplished prior to further flight

or in accordance with a schedule approved

by the FAA.

(g) Reports of Level 2 and Level 3 corrosion

must be submitted at least every three

months to Mitsubishi Heavy Industries, Ltd.,

in accordance with Section 3 of the

Document.

Note 8: Reporting of Level 2 and Level 3

corrosion found as a result of any

opportunity inspections is highly desirable.

(h) An alternative method of compliance or

adjustment of the compliance time, which

provides an acceptable level of safety, may be

used when approved by the Manager, Los

Angeles Aircraft Certification Office (ACO),

FAA, Transport Airplane Directorate.

Operators shall submit their requests through

the cognizant Maintenance Inspector at the

appropriate FAA Flight Standards office,

who may concur or comment and then send

it to the Manager, Los Angeles ACO.

Note 9: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

(i) 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.

(j) Reports of inspection results required by

this AD have been approved by the Office of

Management and Budget (OMB) under the

provisions of the Paperwork Reduction Act of

1980 (44 U.S.C. 3501 et seq.) and have been

assigned OMB Control Number 2120–0056.

Issued in Renton, Washington, on April 10,

1995.

S.R. Miller,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 95–9352 Filed 4–18–95; 8:45 am]

BILLING CODE 4910–13–U

14 CFR Part 39

[Docket No. 94–NM–166–AD]

Airworthiness Directives; British

Aerospace Model Viscount 744, 745D,

and 810 Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Notice of proposed rulemaking

(NPRM).

SUMMARY: This document proposes the

adoption of a new airworthiness

directive (AD) that is applicable to all

British Aerospace Model Viscount 744,

754D, and 810 airplanes. This proposal

would require an inspection to detect

corrosion of the tailplane assemblies,

and correction of discrepancies. This

proposal is prompted by a report of

corrosion on the main spar top and

bottom forward boom of the tailplane

assemblies and reports of cracking in

the upper root joint attachment fitting.

The actions specified by the proposed

AD are intended to prevent such

cracking or corrosion of the main spar

forward booms or the upper root joint

attachment fitting, which consequently