This section of the FEDERAL REGISTER

contains notices to the public of the proposed

issuance of rules and regulations. The

purpose of these notices is to give interested

persons an opportunity to participate in the

rule making prior to the adoption of the final

rules.

Proposed Rules Federal Register

24882

Vol. 65, No. 83

Friday, April 28, 2000

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98–NM–326–AD]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9–80 Series

Airplanes and Model MD–88 Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Supplemental notice of

proposed rulemaking; reopening of

comment period.

SUMMARY: This document revises an

earlier proposed airworthiness directive

(AD), applicable to all McDonnell

Douglas Model DC–9–80 series

airplanes and Model MD–88 airplanes,

that would have superseded an existing

AD that currently requires revisions to

the Airplane Flight Manual (AFM) and

installation of tufts and triangular decals

on the wing upper surfaces. The

proposed AD would have required

installation of an overwing heater

blanket system or a primary wing ice

detection system and a new AFM

revision. For certain airplanes, this

action proposes new repetitive tests and

a one-time inspection, as applicable, to

ensure the integrity of the electrical

installation of the overwing heater

blanket, and corrective action, if

necessary. This new action also

proposes installation of a heater

protection panel or an equipment

protection device on certain overwing

heater blanket systems, which would

constitute terminating action for the

new repetitive tests for affected

airplanes. The actions specified by this

proposed AD are intended to prevent ice

accumulation on the wing upper

surfaces, which could result in ingestion

of ice into one or both engines and

consequent loss of thrust from one or

both engines.

DATES: Comments must be received by

June 12, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 98–NM–

326–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

The Boeing Company, Douglas Products

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:

Albert Lam, Aerospace Engineer,

Systems and Equipment Branch, ANM–

130L, FAA, Transport Airplane

Directorate, Los Angeles Aircraft

Certification Office, 3960 Paramount

Boulevard, Lakewood, California

90712–4137; telephone (562) 627–5346;

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

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 98–NM–326–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.

98–NM–326–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

A proposal to amend part 39 of the

Federal Aviation Regulations (14 CFR

part 39) to add an airworthiness

directive (AD), applicable to all

McDonnell Douglas Model DC–9–80

series airplanes and Model MD–88

airplanes, was published as a notice of

proposed rulemaking (NPRM) in the

Federal Register on March 8, 1999 (64

FR 10959). That NPRM proposed to

supersede AD 92–03–02, amendment

39–8156 (57 FR 2014, January 17, 1992),

which is applicable to all McDonnell

Douglas Model DC–9–80 series

airplanes and Model MD–88 airplanes.

That proposal would have continued to

require a revision to the Airplane Flight

Manual (AFM) to specify restrictions on

operations during icing conditions,

installation of tufts and triangular decals

on the inboard side of the wing upper

surfaces, and a revision to the AFM to

specify restrictions on operations when

such tufts or decals are missing. That

proposal would have added a

requirement for installation of an

overwing heater blanket system or a

primary wing ice detection system, and

a new revision to the AFM to advise the

flightcrew of the hazards associated

with ice accumulation on wing surfaces.

That NPRM was prompted by incidents

in which ice accumulation on the wing

upper surfaces shed into the engines

during takeoff. That condition, if not

corrected, could result in consequent

loss of thrust from one or both engines.

Actions Since Issuance of Previous

Proposal

Since the issuance of that NPRM, the

FAA has received several reports of

Federal Register / Vol. 65, No. 83 / Friday, April 28, 2000 / Proposed Rules 24883

arcing of overwing heater blankets

installed on the wing upper surfaces.

Investigation revealed that the arcing

was caused by damaged wiring in an

overwing heater blanket. Investigation

further revealed that the arcing current

was too low for the circuit breaker of the

overwing heater blanket system to

disconnect power to the heater blanket.

This condition, if not corrected, could

result in a fire on the overwing heater

blanket.

Explanation of Relevant Service

Information

The FAA has reviewed and approved

McDonnell Douglas Alert Service

Bulletin MD80–30A087, dated

September 22, 1997. For airplanes on

which an overwing heater blanket

system has been installed in accordance

with certain service bulletins or

supplemental type certificates (STC),

that service bulletin describes

procedures for repetitive dielectric

withstanding voltage and resistance

tests of overwing heater blankets to

ensure the integrity of the electrical

installation of the overwing heater

blanket and to ensure that there is no

damage to the heater blanket. For

airplanes on which the overwing heater

blanket system was installed in

accordance with TDG Aerospace, Inc.,

STC SA6042NM, the service bulletin

also describes procedures for a one-time

detailed visual inspection to detect

discrepancies of the overwing heater

blanket, including mechanical damage

or punctures in the upper skin of the

blanket, prying damage on the panel,

and fuel leakage. McDonnell Douglas

Alert Service Bulletin MD80–30A087

references TDG Aerospace Document

E95–451, Revision B, dated January 31,

1996, as an additional source of service

information for accomplishment of

corrective actions, including repair or

replacement of the overwing heater

blanket, if any discrepancy is detected.

The FAA also has reviewed and

approved McDonnell Douglas Service

Bulletin MD80–30–090, dated October

19, 1999. For airplanes on which the

overwing heater blanket system was

installed in accordance with certain

service bulletins or STC’s, that service

bulletin describes procedures for

installation of a heater protection panel

(HPP) and associated wiring on the

overwing heater blanket system, or

modification of the existing HPP, if one

is installed. Installation of an HPP is

intended to protect the overwing heater

blanket from damage by detecting

abnormal current flow, and interrupting

and shutting off power to the heater

blanket. Accomplishment of the

installation or modification of the HPP,

as applicable, eliminates the need for

the repetitive tests described in

McDonnell Douglas Alert Service

Bulletin MD80–30A087, dated

September 22, 1997.

Accomplishment of the actions

described in these service bulletins is

intended to adequately address the new

identified unsafe condition (arcing of

overwing heater blankets, which could

result in a fire on the overwing heater

blanket).

Comments

Due consideration has been given to

the comments received in response to

the NPRM, and two comments have

resulted in a change to this proposed

rule.

Request To Incorporate Ground Fault

Protection System

One commenter, the airplane

manufacturer, requests that the

proposed AD be revised to add a

requirement for installation of ground

fault protection for the overwing heater

blanket system. The commenter states

no justification for its request in its

comment. However, as stated

previously, there have been several

incidents of arcing of overwing heater

blankets due to damaged wiring, and the

manufacturer has issued McDonnell

Douglas Service Bulletin MD80–30–090,

described previously, which describes

procedures for installation of ground

fault protection.

The FAA partially concurs with the

commenter’s request. The FAA concurs

that it is necessary to require

installation of ground fault protection

for the overwing heater blanket systems

installed in accordance with certain

service bulletins or STC’s. Therefore,

paragraphs (f)(1)(i) and (f)(1)(ii) of this

supplemental NPRM would require

installation or modification, as

applicable, of an HPP on any overwing

heater blanket system installed in

accordance with McDonnell Douglas

Service Bulletin MD80–30–071,

Revision 02, dated February 6, 1996; or

McDonnell Douglas Service Bulletin

MD80–30–078, Revision 01, dated April

8, 1997. Similarly, paragraph (f)(1)(iii) of

this supplemental NPRM proposes to

require installation of an equipment

protection device (EPD) approved by the

Manager, Los Angeles Aircraft

Certification Office, to provide ground

fault protection for the overwing heater

blanket system installed in accordance

with TDG Aerospace, Inc.,

Supplemental Type Certificate (STC)

SA6042NM. In addition, for airplanes

on which overwing heater blankets are

already installed, this supplemental

NPRM proposes to require

accomplishment of the previously

described repetitive dielectric

withstanding voltage and resistance

tests of overwing heater blankets.

However, the FAA finds that it is not

necessary to require installation of

ground fault protection for airplanes on

which overwing heater blankets are

installed in accordance with

AlliedSignal STC SA6061NM, because a

ground fault protection circuit is

integrated as part of the system.

Request To Reference Holders of STC’s

One commenter states that, although

the McDonnell Douglas service bulletins

are quoted repeatedly in the NPRM by

both name and service bulletin

numbers, the NPRM makes no mention

of the holders of the STC’s referenced in

paragraph (d)(1) of the NPRM. The

commenter requests that the holders of

the STC’s be identified in the AD.

The FAA concurs with the

commenter’s request. Therefore,

paragraph (f)(1)(iii)(B) identifies TDG

Aerospace, Inc., as the holder of STC

6042NM, and paragraph (f)(1)(iii)(C) of

this supplemental NPRM identifies

AlliedSignal as the holder of STC

SA6061NM.

Request To Revise Cost Impact

Information

One commenter, the airplane

manufacturer, requests revisions to the

cost impact estimates for installation of

the wing heater system and primary

wing ice detector system. Certain

changes suggested by the commenter are

related to the incorporation of the

ground fault protection system along

with the wing heater system; various

other changes relate to the estimate of

work hours and costs for installation of

the primary wing ice detection system.

The commenter provides no

justification for its requests, but does

indicate that the cost of parts will vary

depending on factors such as parts

suppliers, airplane fleet size, and

airplane configuration.

The FAA partially concurs with the

commenter’s requests. The FAA finds

that it is appropriate to update the cost

estimate in this supplemental NPRM to

reflect the work hours and parts costs

associated with installation of the HPP

or EPD along with the wing heater

system. Therefore, this supplemental

NPRM has been revised to update the

cost of installation of the overwing

heater blankets to reflect the figures

provided by the commenter. The FAA

has also determined that it is

appropriate to revise the estimated costs

for installation of the primary wing ice

detection system; however, the cost

estimates have been updated to reflect

24884 Federal Register / Vol. 65, No. 83 / Friday, April 28, 2000 / Proposed Rules

the most recent information provided by

the manufacturer and do not necessarily

reflect the figures provided by the

commenter in its written comment.

Explanation of New Requirements of

Proposal

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

continue to require a revision to the

Airplane Flight Manual (AFM) to

specify restrictions on operations during

icing conditions, installation of tufts

and triangular decals on the inboard

side of the wing upper surfaces, and a

revision to the AFM to specify

restrictions on operations when such

tufts or decals are missing. The

proposed AD would also require

installation of an overwing heater

blanket system or a primary wing ice

detection system, and a new revision to

the AFM to advise the flightcrew of the

hazards associated with ice

accumulation on wing surfaces.

Installation of an overwing heater

blanket system, if accomplished, would

be required to be accomplished in

accordance with the applicable service

bulletin described in the NPRM, except

as discussed in the ‘‘Differences

Between Proposed Rule and Service

Bulletins’’ section of the original NPRM;

or in accordance with certain STC’s.

Installation of a primary wing ice

detection system, if accomplished,

would be required to be accomplished

in accordance with a method approved

by the FAA.

For certain airplanes on which an

overwing heater blanket system has

already been installed prior to the

effective date of the AD, the proposed

AD also would require repetitive tests to

ensure the integrity of the electrical

installation of the overwing heater

blanket; a one-time inspection to detect

discrepancies in repaired areas of the

overwing heater blanket system, as

applicable; and corrective action, if

necessary. The proposed AD also would

require installation or modification of

an HPP, as applicable, or installation of

an EPD, to provide circuit protection to

the overwing heater blanket system.

Such installation or modification, as

applicable, would constitute

terminating action for the new proposed

repetitive tests for affected airplanes.

The repetitive inspections and

installation or modification of an HPP,

as applicable, would be required to be

accomplished in accordance with the

service bulletins described previously,

except as discussed below. Installation

of an EPD would be required to be

accomplished in accordance with a

method approved by the FAA.

Explanation of Differences Between

Service Bulletins and Supplemental

NPRM

Operators should note that, although

McDonnell Douglas Service Bulletin

MD80–30–090 recommends that an HPP

be installed in conjunction with

installation of an overwing heater

blanket within 18 months after receipt

of that service bulletin, this

supplemental NPRM proposes to require

installation of an HPP (or an EPD)

within 3 years after the effective date of

this AD. The FAA finds that it is

appropriate for the HPP (or EPD) to be

installed in conjunction with the

overwing heater blanket system, and the

compliance time for installation of the

overwing heater blanket system

specified in this proposed AD is 3 years

after the effective date of this AD.

Therefore, the FAA finds that it is

appropriate to require installation of

both the overwing heater blanket system

and an HPP or EPD within 3 years after

the effective date of this AD. However,

for overwing heater blankets installed

prior to the effective date of this AD

without an HPP or EPD, this proposed

AD would require repetitive tests,

described previously, to ensure the

integrity of the electrical installation of

the overwing heater blanket (and a onetime detailed visual inspection to detect

discrepancies in repaired areas of the

overwing heater blanket system, if

applicable) until an HPP or EPD is

installed.

Conclusion

Since these changes expand the scope

of the originally proposed rule, the FAA

has determined that it is necessary to

reopen the comment period to provide

additional opportunity for public

comment.

Cost Impact

There are approximately 1,153

airplanes of the affected design in the

worldwide fleet. The FAA estimates that

643 airplanes of U.S. registry would be

affected by this proposed AD.

The AFM revision that is currently

required by AD 92–03–02 takes

approximately 1 work hour 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 AFM revision on U.S.

operators is estimated to be $38,580, or

$60 per airplane.

The revision of the CDL that is

currently required by AD 92–03–02

takes approximately 1 work hour per

airplane to accomplish, at an average

labor rate of $60 per work hour. Based

on these figures, the cost impact of the

CDL revision on U.S. operators is

estimated to be $38,580, or $60 per

airplane.

The installation of tufts and decals

that is currently required by AD 92–03–

02 takes approximately 3 work hours

per airplane to accomplish, at an

average labor rate of $60 per work hour.

Required parts cost approximately $25

per airplane. Based on these figures, the

cost impact of the currently required

installation of tufts and decals on U.S.

operators is estimated to be $131,815, or

$205 per airplane.

The installation of the wing heater

system that is proposed as one option

for compliance with this AD action

would take approximately 200 to 350

work hours per airplane to accomplish,

at an average labor rate of $60 per work

hour. Required parts would cost

approximately $76,000 to $130,000 per

airplane, depending on suppliers,

airplane fleet size, and configuration.

Based on these figures, the cost impact

of the installation proposed by this AD

on U.S. operators is estimated to range

from $88,000 to $151,000 per airplane.

In lieu of installation of a wing heater

system, this proposed AD provides for

installation of a primary wing ice

detector system. Because the

manufacturer has not issued service

information that describes the

procedures for such an installation, the

FAA is unable at this time to provide

specific information as to the number of

work hours or cost of parts that would

be required to accomplish that proposed

installation. However, based on

estimated costs provided by the

manufacturer, the FAA can reasonably

estimate that the proposed installation

would require 290 work hours to

accomplish, at an average labor rate of

$60 per work hour. The cost of required

parts is estimated to range from $30,000

to $70,000 per airplane, depending on

fleet size and airplane configuration.

Based on these figures, the cost impact

of the installation of a primary wing ice

detector system proposed by this AD on

U.S. operators is estimated to range from

$47,400 to $87,400 per airplane.

The new AFM revision that is

proposed in this AD action would take

approximately 1 work hour per airplane

to accomplish, at an average labor rate

of $60 per work hour. Based on these

figures, the cost impact of the new AFM

revision proposed by this AD on U.S.

operators is estimated to be $38,580, or

$60 per airplane.

For affected airplanes, the new

repetitive tests proposed in this AD

action would take approximately 3 work

hours per airplane to accomplish, at an

Federal Register / Vol. 65, No. 83 / Friday, April 28, 2000 / Proposed Rules 24885

average labor rate of $60 per work hour.

Based on these figures, the cost impact

of the repetitive tests proposed by this

AD on U.S. operators is estimated to be

$180 per airplane, per test cycle.

For affected airplanes, the one-time

detailed visual inspection proposed in

this AD action would take

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

detailed visual inspection proposed by

this AD on U.S. operators is estimated

to be $180 per airplane.

For airplanes listed in Group 1 of

McDonnell Douglas Alert Service

Bulletin MD80–30–090, the

modification of the existing HPP would

take approximately 5 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour. The

manufacturer has committed previously

to its customers that it will bear the cost

of necessary parts. As a result, the cost

of those parts is not attributable to this

proposed AD. Based on these figures,

the cost impact of the proposed AD on

U.S. operators is estimated to be $300

per airplane.

For airplanes listed in Group 2 of

McDonnell Douglas Alert Service

Bulletin MD80–30–090, the installation

of the HPP and associated wiring would

take approximately 3 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour. The

manufacturer has committed previously

to its customers that it will bear the cost

of necessary parts. As a result, the cost

of those parts is not attributable to this

proposed AD. Based on these figures,

the cost impact of the proposed AD on

U.S. operators is estimated to be $180

per airplane.

Because no service information that

describes procedures for installation of

an EPD has been issued, such

installation for affected airplanes would

be required to be accomplished in

accordance with a method approved by

the FAA, and the FAA is unable at this

time to provide specific information as

to the number of work hours that would

be required to accomplish the proposed

installation. However, based on the

information available for installation of

an HPP, the FAA estimates that the

proposed installation of an EPD would

require approximately 3 hours per

airplane, at an average labor rate of $60

per work hour. Based on information

from the supplier on parts cost for the

EPD, the cost of required parts is

estimated to be $5,475 per airplane.

Based on these figures, the cost impact

of the proposed AD on U.S. operators is

estimated to be $5,655 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.

However, the FAA has been advised

that the terminating modification has

already been installed on a number of

airplanes that are subject to this AD.

Therefore, the future economic cost

impact of this rule on U.S. operators is

expected to be less than the cost impact

figures indicated above.

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

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 39–8156 (57 FR

2014, January 17, 1992), and by adding

a new airworthiness directive (AD), to

read as follows:

McDonnell Douglas: Docket 98–NM–326–

AD. Supersedes AD 92–03–02,

Amendment 39–8156.

Applicability: All Model DC–9–81, –82,

–83, and –87 series airplanes; and Model

MD–88 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 request approval for an

alternative method of compliance in

accordance with paragraph (h)(1) of this AD.

The request should include an assessment of

the effect of the modification, alteration, or

repair on the unsafe condition addressed by

this AD; and, if the unsafe condition has not

been eliminated, the request should include

specific proposed actions to address it.

Compliance: Required as indicated, unless

accomplished previously.

To prevent ice accumulation on the wing

upper surfaces, which could result in

ingestion of ice into one or both engines and

consequent loss of thrust from one or both

engines, accomplish the following:

Restatement of Requirements of AD 92–03–

02

Airplane Flight Manual Revision

(a) Within 10 days after January 17, 1992

(the effective date of AD 92–03–02,

amendment 39–8156), revise the Limitations

Section of the FAA-approved Airplane Flight

Manual (AFM) to include the following. This

may be accomplished by inserting a copy of

this AD in the AFM.

‘‘Ice on Wing Upper Surfaces

Caution

Ice shedding from the wing upper surface

during takeoff can cause severe damage to

one or both engines, leading to surge,

vibration, and complete thrust loss. The

formation of ice can occur on wing surfaces

during exposure of the airplane to normal

icing conditions. Clear ice can also occur on

the wing upper surfaces when cold-soaked

fuel is in the main wing fuel tanks, and the

airplane is exposed to conditions of high

humidity, rain, drizzle, or fog at ambient

temperatures well above freezing. Often, the

ice accumulation is clear and difficult to

detect visually. The ice forms most

frequently on the inboard, aft corner of the

main wing tanks. [END OF CAUTIONARY

NOTE]

The wing upper surfaces must be

physically checked for ice when the airplane

has been exposed to conditions conducive to

ice formation. Takeoff may not be initiated

unless the flight crew verifies that a visual

check and a physical (hands-on) check of the

wing upper surfaces have been

accomplished, and that the wing is clear of

ice accumulation when any of the following

conditions occur:

24886 Federal Register / Vol. 65, No. 83 / Friday, April 28, 2000 / Proposed Rules

(1) When the ambient temperature is less

than 50 degrees F and high humidity or

visible moisture (rain, drizzle, sleet, snow,

fog, etc.) is present;

(2) When frost or ice is present on the

lower surface of either wing;

(3) After completion of de-icing.

When tufts and triangular decals are

installed in accordance with McDonnell

Douglas MD–80 Service Bulletin 30–59, the

physical check may be made by assuring that

all installed tufts move freely.

Note

This limitation does not relieve the

requirement that aircraft surfaces are free of

frost, snow, and ice accumulation, as

required by Federal Aviation Regulations

Sections 91.527 and 121.629. [END OF

NOTE]’’

AFM Configuration Deviation List Revision

(b) Within 10 days after January 17, 1992,

revise the Configuration Deviation List (CDL)

Appendix of the FAA-approved AFM to

include the following. This may be

accomplished by inserting a copy of this AD

in the AFM.

‘‘30–80–01 Triangular Decal and Tuft

Assemblies

Up to two (2) decals or tufts per side may

be missing, provided:

(a) At least one decal and tuft on each side

is located along the aft spar line; and

(b) The tufts are used for performing the

physical check to determine that the upper

wing is free of ice by observing that the tufts

move freely.

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

missing, provided:

(a) Takeoff may not be initiated unless the

flight crew verifies that a physical (hands-on)

check is made of the upper wing in the

location of the missing decals and/or tufts to

assure that there is no ice on the wing when

icing conditions exist;

OR

(b) When the ambient temperature is more

than 50 degrees F.’’

Installation of Tufts and Triangular Decals

(c) Within 30 days after January 17, 1992,

install tufts and triangular decals on the

inboard side of the wings’ upper surfaces, in

accordance with McDonnell Douglas Service

Bulletin 30–59, dated September 18, 1989;

Revision 1, dated January 5, 1990; or

Revision 2, dated August 15, 1990.

New Requirements of This AD

Repetitive Tests and One-Time Inspection

(d) For airplanes on which an overwing

heater blanket system was installed without

installation of a heater protection panel

(HPP) or an equipment protection device

(EPD) prior to the effective date of this AD:

Within 60 days after the effective date of this

AD, accomplish the actions specified in

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

applicable.

(1) For airplanes on which the overwing

heater blanket system was installed in

accordance with McDonnell Douglas Service

Bulletin MD80–30–071, Revision 02, dated

February 6, 1996; or McDonnell Douglas

Service Bulletin MD80–30–078, Revision 01,

dated April 8, 1997: Accomplish paragraphs

(d)(1)(i) and (d)(1)(ii) of this AD.

(i) Remove secondary access covers, and

perform a one-time detailed visual inspection

to detect discrepancies (mechanical damage

or punctures in the upper skin of the blanket,

prying damage on the panel, and fuel

leakage) of the overwing heater blanket, in

accordance with McDonnell Douglas Alert

Service Bulletin MD80–30A087, dated

September 22, 1997. And,

(ii) Accomplish paragraph (d)(1)(ii)(A) or

(d)(1)(ii)(B) of this AD.

(A) Perform dielectric withstanding voltage

and resistance tests in accordance with

McDonnell Douglas Alert Service Bulletin

MD80–30A087, dated September 22, 1997.

Repeat the tests thereafter at intervals not to

exceed 150 days, until installation of an HPP

in accordance with paragraph (f)(1)(i) or

(f)(1)(ii) of this AD, as applicable.

(B) Deactivate the overwing heater blanket

system until accomplishment of dielectric

withstanding voltage and resistance tests

specified in paragraph (1)(2)(ii)(A). If the

overwing heater blanket system is

deactivated as provided by this paragraph,

continue to accomplish the requirements of

paragraphs (a), (b), and (c) of this AD.

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 such as mirror,

magnifying lenses, etc., may be used. Surface

cleaning and elaborate access procedures

may be required.’’

(2) For airplanes on which the overwing

heater blanket system was installed in

accordance with TDG Aerospace, Inc., STC

SA6042NM: Accomplish paragraphs (d)(2)(i)

and (d)(2)(ii) of this AD.

(i) Remove secondary access covers, and

perform a one-time detailed visual inspection

to detect discrepancies (mechanical damage

or punctures in the upper skin of the blanket,

prying damage on the panel, and fuel

leakage) of the overwing heater blanket, in

accordance with McDonnell Douglas Alert

Service Bulletin MD80–30A087, dated

September 22, 1997. And,

(ii) Accomplish paragraph (d)(2)(ii)(A) or

(d)(2)(ii)(B) of this AD.

(A) Perform dielectric withstanding voltage

and resistance tests in accordance with

McDonnell Douglas Alert Service Bulletin

MD80–30A087, dated September 22, 1997.

Repeat the tests thereafter at intervals not to

exceed 150 days, until installation of an EPD

in accordance with paragraph (f)(1)(iii)(B) of

this AD.

(B) Deactivate overwing heater blanket

system until accomplishment of dielectric

withstanding voltage and resistance tests

specified in paragraph (d)(2)(ii)(A). If the

overwing heater blanket system is

deactivated as provided by this paragraph,

continue to accomplish the requirements of

paragraphs (a), (b), and (c) of this AD.

Corrective Action

(e) If any discrepancy is detected during

any inspection or test performed in

accordance with paragraph (d) of this AD,

prior to further flight, repair or replace the

affected heater blanket, in accordance with

McDonnell Douglas Alert Service Bulletin

MD80–30A087, dated September 22, 1997.

Note 3: McDonnell Douglas Alert Service

Bulletin MD80–30A087, dated September 22,

1997, references TDG Aerospace Document

E95–451, Revision B, dated January 31, 1996,

as an additional source of service information

for accomplishment of repair or replacement

of the overwing heater blanket.

Installation of Overwing Heater Blanket or

Primary Wing Ice Detection System

(f) Within 3 years after the effective date of

this AD, accomplish the requirements of

either paragraph (f)(1) or (f)(2) of this AD.

(1) Accomplish the actions specified in

paragraph (f)(1)(i), (f)(1)(ii), or (f)(1)(iii) of

this AD, as applicable.

(i) For airplanes listed in Group 1 in

McDonnell Douglas Service Bulletin MD80–

30–090, dated October 19, 1999: Install an

overwing heater blanket system in

accordance with McDonnell Douglas Service

Bulletin MD80–30–071, Revision 02, dated

February 6, 1996; and modify and reidentify

the existing HPP in accordance with

McDonnell Douglas Service Bulletin MD80–

30–090. Modification of the existing HPP in

accordance with this paragraph constitutes

terminating action for the repetitive

inspections required by (d)(1)(ii)(A) of this

AD.

(ii) For airplanes listed in Group 2 in

McDonnell Douglas Service Bulletin MD80–

30–090, dated October 19, 1999: Install an

overwing heater blanket system in

accordance with McDonnell Douglas Service

Bulletin MD80–30–078, Revision 01, dated

April 8, 1997; and install an HPP and

associated wiring in accordance with

McDonnell Douglas Service Bulletin MD80–

30–090. Installation of an HPP and associated

wiring in accordance with this paragraph

constitutes terminating action for the

repetitive inspections required by

(d)(1)(ii)(A) of this AD.

(iii) For airplanes other than those

identified in paragraph (f)(1)(i) or (f)(1)(ii) of

this AD: Accomplish the requirements of

paragraph (f)(1)(iii)(A), (f)(1)(iii)(B), or

(f)(1)(iii)(C) of this AD.

(A) Accomplish the actions specified in

either paragraph (f)(1)(i) or (f)(1)(ii) of this

AD.

(B) Install an overwing heater blanket

system in accordance with TDG Aerospace,

Inc., Supplemental Type Certificate (STC)

SA6042NM, and install an EPD that provides

a circuit protection function to the overwing

heater blanket, in accordance with a method

approved by the Manager, Los Angeles

Aircraft Certification Office (ACO), FAA,

Transport Airplane Directorate. Installation

of an EPD in accordance with this paragraph

constitutes terminating action for the

repetitive inspections required by

(d)(2)(ii)(A) of this AD.

(C) Install an overwing heater blanket

system in accordance with AlliedSignal STC

SA6061NM.

Federal Register / Vol. 65, No. 83 / Friday, April 28, 2000 / Proposed Rules 24887

(2) Install an FAA-approved primary wing

ice detection system in accordance with a

method approved by the Manager, Los

Angeles ACO.

Note 4: McDonnell Douglas has received

FAA approval of an acceptable primary wing

ice detection system. This modification has

been assigned a McDonnell Douglas service

bulletin number but, at this time, no service

bulletin is available.

AFM Revision

(g) Prior to further flight after

accomplishment of the installation required

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

the Limitations Section of the FAA-approved

AFM to include the following. This may be

accomplished by inserting a copy of this AD

in the AFM. After accomplishment of the

installation required by paragraph (f) of this

AD and this AFM revision, the AFM

revisions required by paragraphs (a) and (b)

of this AD may be removed from the AFM,

and the tufts and triangular decals required

by paragraph (c) of this AD may be removed

from the airplane.

‘‘Ice on Wing Upper Surfaces

Caution

Ice shedding from the wing upper surface

during takeoff can cause severe damage to

one or both engines, leading to surge,

vibration, and complete thrust loss. The

formation of ice can occur on wing surfaces

during exposure of the airplane to normal

icing conditions. Clear ice can also occur on

the wing upper surfaces when cold-soaked

fuel is in the main wing fuel tanks, and the

airplane is exposed to conditions of high

humidity, rain, drizzle, or fog at ambient

temperatures well above freezing. Often, the

ice accumulation is clear and difficult to

detect visually. The ice forms most

frequently on the inboard, aft corner of the

main wing tanks. [END OF CAUTIONARY

NOTE]’’

Alternative Methods of Compliance

(h)(1) An alternative method of compliance

or adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager, Los

Angeles ACO. Operators shall submit their

requests through an appropriate FAA

Principal Maintenance Inspector, who may

add comments and then send it to the

Manager, Los Angeles ACO.

(2) Alternative methods of compliance,

approved previously in accordance with AD

92–03–02, amendment 39–8156, are NOT

approved as alternative methods of

compliance with this AD.

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.

Special Flight Permits

(i) 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 April 24,

2000.

Donald L. Riggin,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 00–10672 Filed 4–27–00; 8:45 am]

BILLING CODE 4910–13–P

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000–NM–90–AD]

RIN 2120–AA64

Airworthiness Directives; Bombardier

Model DHC–7–100, and DHC–8–100,

–200, and –300 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 all

Bombardier Model DHC–7–100, and

DHC–8–100, –200, and –300 series

airplanes. This proposal would require

a one-time inspection of maintenance

records to determine the method used

during the most recent weight and

balance check of the airplane and, if

necessary, accomplishment of a weight

and balance check. This proposal is

prompted by issuance of mandatory

continuing airworthiness information by

a foreign civil airworthiness authority.

The actions specified by the proposed

AD are intended to prevent unusual

handling characteristics and consequent

reduced controllability during ground

operations due to incorrect methods of

weighing and balancing the airplane.

DATES: Comments must be received by

May 30, 2000.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–114,

Attention: Rules Docket No. 2000–NM–

90–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

Bombardier, Inc., Canadair, Aerospace

Group, P.O. Box 6087, Centre-ville,

Montreal, Quebec H3C 3G9, Canada.

This information may be examined at

the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW.,

Renton, Washington; or at the FAA,

Engine and Propeller Directorate, New

York Aircraft Certification Office, 10

Fifth Street, Third Floor, Valley Stream,

New York.

FOR FURTHER INFORMATION CONTACT:

James E. Delisio, Aerospace Engineer,

Airframe and Propulsion Branch, ANE–

171, FAA, Engine and Propeller

Directorate, New York Aircraft

Certification Office, 10 Fifth Street,

Third Floor, Valley Stream, New York

11581; telephone (516) 256–7521; fax

(516) 568–2716.

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 2000–NM–90–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.

2000–NM–90–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

Transport Canada Civil Aviation

(TCCA), which is the airworthiness

authority for Canada, notified the FAA

that an unsafe condition may exist on

all Bombardier Model DHC–7–100, and

all Model DHC–8–100, –200, and –300