16814 Federal Register / Vol. 60, No. 63 / Monday, April 3, 1995 / Proposed Rules

and the applicable bilateral

airworthiness agreement. Pursuant to

this bilateral airworthiness agreement,

the DGAC has kept the FAA informed

of the situation described above. The

FAA has examined the findings of the

DGAC, 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 an unsafe condition has been

identified that is likely to exist or

develop on other airplanes of the same

type design registered in the United

States, the proposed AD would require

a mechanical integrity inspection to

detect discrepancies of the thrust

reverser control lever spring having part

number (P/N) A2791294520000, and an

operational test to verify the integrity of

the flight inhibition circuit of the thrust

reverser system. It also requires the

correction of discrepancies or

deactivation of the associated thrust

reverser. The actions are required to be

accomplished in accordance with the

All Operators Telex described

previously.

The FAA estimates that 21 airplanes

of U.S. registry would be affected by this

proposed AD, that it would take

approximately 6 work hours per

airplane to accomplish the proposed

actions, and that the average labor rate

is $60 per work hour. Required parts

would cost approximately $55 per

airplane. Based on these figures, the

total cost impact of the proposed AD on

U.S. operators is estimated to be $8,715,

or $415 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 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:

Airbus Industrie: Amendment 39– .

Docket 95–NM–34–AD.

Applicability: Model A300–B2 and –B4

series airplanes, equipped with General

Electric CF6–50 series engines or Pratt &

Whitney JT9D–59A engines; 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 (b) 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.

To ensure the detection of broken or

deformed thrust reverser control lever

springs that could lead to uncommanded

deployment of a thrust reverser and

subsequent reduced controllability of the

airplane, accomplish the following:

(a) Within 500 flight hours after the

effective date of this AD, perform a

mechanical integrity inspection to detect

discrepancies of the thrust reverser control

lever spring having part number (P/N)

A2791294520000, and an operational test to

verify the integrity of the flight inhibition

circuit of the thrust reverser system, in

accordance with Airbus All Operators Telex

AOT 78–03, Revision 1, dated July 20, 1994.

(1) If no discrepancies are detected, no

further action is required by this AD.

(2) If the control lever spring is found

broken or out of tolerance, prior to further

flight, replace it with a new control lever

spring or deactivate the associated thrust

reverser in accordance with the AOT.

(3) If the flight inhibition circuit of the

thrust reverser system fails the operational

test, prior to further flight, determine the

origin of the malfunction, in accordance with

the AOT.

(i) If the origin of the malfunction is

identified, prior to further flight, repair the

flight inhibition circuit in accordance with

the AOT.

(ii) If the origin of the malfunction is not

identified, prior to further flight, replace the

relay having P/N 125GB or 124GB, and repeat

the operational test, in accordance with the

AOT. If the malfunction is still present, prior

to further flight, inspect and repair the wiring

in accordance with the AOT. If the

malfunction is still present following the

inspection and repair, prior to further flight,

deactivate the associated thrust reverser in

accordance with the AOT.

(b) 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,

Standardization Branch, FAA, Transport

Airplane Directorate, ANM–113. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Standardization

Branch, ANM–113.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Standardization Branch,

ANM–113.

(c) 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.

Issued in Renton, Washington, on March

27, 1995.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 95–8078 Filed 3–31–95; 8:45 am]

BILLING CODE 4910–13–U
Federal Register / Vol. 60, No. 63 / Monday, April 3, 1995 / Proposed Rules 16815

14 CFR Part 39

[Docket No. 95–NM–07–AD]

Airworthiness Directives; Boeing

Model 757 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

Boeing Model 757 series airplanes, that

currently requires various modifications

and terminating actions for the

passenger door, and repair, if necessary.

This action would require additional

inspections, and replacement of certain

parts, if necessary. This proposal is

prompted by reports of excessive gaps

between lockout cams and crank stops,

which resulted in broken power assist

triggers. The actions specified by this

proposed AD are intended to prevent

broken power assist triggers, which

could result in an inoperative door

opening system during an emergency

evacuation.

DATES: Comments must be received by

May 31, 1995.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 95–NM–

07–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

Comments may be inspected at this

location between 9 a.m. and 3 p.m.,

Monday through Friday, except Federal

holidays.

The service information referenced in

the proposed rule may be obtained from

Boeing Commercial Airplane Group,

P.O. Box 3707, Seattle, Washington

98124–2207. This information may be

examined at the FAA, Transport

Airplane Directorate, 1601 Lind

Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Roy

Boffo, Aerospace Engineer, Airframe

Branch, ANM–120S, FAA, Transport

Airplane Directorate, Seattle Aircraft

Certification Office, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056;

telephone (206) 227–2780; fax (206)

227–1181.

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 95–NM–07–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.

95–NM–07–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On March 13, 1991, the FAA issued

AD 91–07–09, amendment 39–6951 (56

FR 12111, March 22, 1991), applicable

to certain Boeing Model 757 series

airplanes, which requires various

modifications and terminating actions

for the passenger door, and repair, if

necessary. That action was prompted by

reports of fractured emergency power

assist triggers. The requirements of that

AD are intended to prevent an

inoperative emergency power assist

door opening system during an

emergency evacuation.

Since the issuance of that AD, the

FAA has received additional reports of

broken power assist triggers. One broken

power assist trigger was found on a door

before the airplane was delivered to the

operator. The FAA also has received

reports of excessive gaps between

lockout cams and crank stops.

Investigation has revealed that when the

crank stop is in the arm/engage position,

excessive fore and aft clearance between

the lockout cam and the crank stop can

result in broken power assist triggers.

This condition, if not detected and

corrected, could result in an inoperative

power assist system of the passenger

door during an emergency evacuation.

Based on these findings, the FAA has

determined that the distance between

the lockout cam and the crank stop must

be measured to ensure that gaps are not

excessive. In addition, the FAA finds

that inspections must be performed to

detect damaged or cracked power assist

triggers that may prevent the door

opening systems from operating.

The FAA has reviewed and approved

Boeing Alert Service Bulletin 757–

52A0023, Revision 3, dated November

18, 1993, which describes procedures

for repetitive inspections to detect worn,

damaged, or cracked power assist

triggers, repair of worn fittings, and

replacement of any discrepant trigger.

The alert service bulletin also describes

procedures for repetitive measurement

of the clearance between the lockout

cam and the crank stop, and

replacement of the lockout cam, if

necessary.

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 91–07–09 to continue to

require various inspections and

modifications of certain mechanisms of

the passenger doors, and replacement of

certain parts, if necessary. This AD

would require repetitive inspections to

detect worn, damaged, or cracked power

assist triggers, repair of worn triggers,

and replacement, if necessary. This AD

will also require repetitive

measurements of the clearance between

the lockout cam and the crank stop; and

replacement of the lockout cams, if

necessary. These actions would be

required to be accomplished in

accordance with the alert service

bulletin described previously.

There are approximately 578 Model

757 series airplanes of the affected

design in the worldwide fleet. The FAA

estimates that 323 airplanes (6

passenger doors per airplane) of U.S.

registry would be affected by this

proposed AD, that it would take

approximately 12 work hours (2 work

hours per door) to accomplish the

proposed actions, and that 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 is

estimated to be $232,560, or $720 per

airplane ($120 per door), per inspection

cycle.

Should an operator be required to

accomplish the necessary replacement

of power assist triggers, it would take

approximately 18 work hours per
16816 Federal Register / Vol. 60, No. 63 / Monday, April 3, 1995 / Proposed Rules

airplane (3 work hours per passenger

door) to accomplish the replacement, at

an average labor rate of $60 per work

hour. Required parts would cost

approximately $1,800 per airplane ($300

per passenger door). Based on these

figures, the total cost impact of any

necessary replacement action is

estimated to be $2,880 per airplane

($480 per passenger door).

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 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

removing amendment 39–6951 (56 FR

12111, March 22, 1991), and by adding

a new airworthiness directive (AD), to

read as follows:

Boeing: Docket 95–NM–07–AD. Supersedes

AD 91–07–09, Amendment 39–6951.

Applicability: Model 757 series airplanes,

as listed in any of the following service

bulletins: Boeing Service Bulletin 757–52–

0042 dated March 30, 1989, Boeing Service

Bulletin 757–52–0042, Revision 1, dated

April 26, 1990; and Boeing Alert Service

Bulletin 757–52A0023, Revision 3, dated

November 18, 1993; 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 (f) 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.

To ensure proper operation of the door

opening system during an emergency

evacuation, accomplish the following:

(a) For airplanes identified as Group 1 in

Boeing Service Bulletin 757–52–0042, dated

March 30, 1989, and Revision 1, dated April

26, 1990: Within 350 flight hours after

January 6, 1990 (the effective date of AD 89–

25–09, amendment 39–6407), accomplish

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

in accordance with either service bulletin.

Any interference or improper clearance

detected during any inspections required by

this paragraph must be repaired prior to

further flight, in accordance with either

service bulletin.

(1) Modify the forward right-hand

passenger door.

(2) Inspect all passenger doors for evidence

of interference between the trigger support

housing and the upper hinge arm.

(3) Inspect all passenger doors for proper

clearance between the power assist trigger

and the door and fuselage skin.

(b) For all airplanes identified in Boeing

Service Bulletin 757–52–0042, dated March

30, 1989, and Revision 1, dated April 26,

1990: Within 350 flight hours after January 6,

1990 (the effective date of AD 89–25–09,

amendment 39–6407), and thereafter at

intervals not to exceed 6 months, accomplish

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

this AD, in accordance with either service

bulletin. Any damage, improper adjustment,

or improper operation detected during any of

the inspections required by this paragraph

must be repaired prior to further flight, in

accordance with either service bulletin.

(1) Inspect the forward doors for proper

adjustment of the lockout mechanism of the

door emergency power assist system.

(2) Inspect all passenger door emergency

power assist triggers for wear marks, damage,

or fracture.

(3) Inspect trigger spring cylinders for

proper operation.

(4) Inspect roller arms for damage.

(c) For all airplanes identified in Boeing

Service Bulletin 757–52–0042, Revision 1,

dated April 26, 1990: Within 18 months after

April 29, 1991 (the effective date of AD 91–

07–09, amendment 39–6951), accomplish

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

this AD, in accordance with Section III, Part

III, of the service bulletin. Any damage,

defect, improper adjustment, or improper

operation detected during any inspection

required by this paragraph must be repaired,

prior to further flight, in accordance with the

service bulletin. Accomplishment of the

actions required by this paragraph constitutes

terminating action for the periodic

inspections required by paragraph (b) of this

AD.

(1) On forward doors, install the lockout

link and inspect the lockout mechanism for

proper adjustment.

(2) On all passenger doors, install the new

trigger guard. and inspect the emergency

power assist triggers for wear marks, damage,

or fracture.

(3) On all passenger doors, modify the

trigger spring cylinder end cap and inspect

the spring cylinder for proper operation.

(4) On all passenger doors, inspect roller

arms for damage.

(d) For all airplanes identified in Boeing

Alert Service Bulletin 757–52A0023,

Revision 3, dated November 18, 1993: Within

6 months after the effective date of this AD,

perform an inspection to detect wear marks,

damage, or cracking on the upper surface of

the emergency power assist triggers at all

passenger doors, in accordance with the alert

service bulletin. Repeat the inspection

thereafter at intervals not to exceed 6 months.

(1) If any wear mark is detected, prior to

further flight, repair in accordance with the

alert service bulletin.

(2) If any damage or cracking is detected,

prior to further flight, replace the power

assist triggers, in accordance with the alert

service bulletin.

(e) For all airplanes identified in Boeing

Alert Service Bulletin 757–52A0023,

Revision 3, dated November 18, 1993: Within

6 months after the effective date of this AD,

measure the clearance between the lockout

cam and the crank stop, in accordance with

the alert service bulletin.

(1) If the clearance between the lockout

cam and the crank stop is within the limits

specified in the alert service bulletin,

thereafter, repeat the measurement at

intervals not to exceed 6 months.

(2) If the clearance between the lockout

cam and the crank stop is beyond the limits

specified in the alert service bulletin, prior to

further flight, accomplish either paragraph

(e)(2)(i) or (e)(2)(ii) of this AD. Thereafter,
Federal Register / Vol. 60, No. 63 / Monday, April 3, 1995 / Proposed Rules 16817

repeat the measurement at intervals not to

exceed 6 months.

(i) Adjust the lockout cam until the correct

clearance is obtained, in accordance with the

alert service bulletin, Or

(ii) If correct clearance cannot be obtained

by adjusting the lockout cam, replace the

lockout cam, in accordance with the alert

service bulletin.

(f) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager, Seattle

Aircraft Certification Office (ACO), FAA,

Transport Airplane Directorate. Operators

shall submit their requests through an

appropriate FAA Principal Maintenance

Inspector, who may add comments and then

send it to the Manager, Seattle ACO.

Note 2: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Seattle ACO.

(g) 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.

Issued in Renton, Washington, on March

27, 1995.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 95–8079 Filed 3–31–95; 8:45 am]

BILLING CODE 4910–13–U

14 CFR Part 39

[Docket No. 95–NM–08–AD]

Airworthiness Directives; Boeing

Model 767 Series Airplanes Equipped

With Over-Wing Escape Slides

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

Boeing Model 767 series airplanes

equipped with over-wing escape slides,

that currently requires modification of

the trailing edge panels and the aft flaps.

That AD was prompted by the results of

functional tests of over-wing escape

slides, which revealed that some slides

were damaged when they were

deployed across sharp corners on the

trailing edge of the wing and the large

gaps between the trailing edge panels of

the wing. This action would expand the

applicability of the existing AD to

include additional airplanes. The

actions specified by the proposed AD

are intended to prevent damage to the

over-wing escape slide, which could

hinder inflation of the slide to a usable

configuration during an emergency

evacuation.

DATES: Comments must be received by

May 15, 1995.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 95–NM–

08–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 Airplane Group,

P.O. Box 3707, Seattle, Washington

98124–2207.

This information may be examined at

the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW.,

Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Dorothy Lundy, Aerospace Engineer,

ANM–120S, Airframe Branch, FAA,

Transport Airplane Directorate, Seattle

Aircraft Certification Office, 1601 Lind

Avenue, SW., Renton, Washington

98055–4056; telephone (206) 227–2769;

fax (206) 227–1181.

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 95–NM–08–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.

95–NM–08–AD, 1601 Lind Avenue,

SW., Renton, Washington 98055–4056.

Discussion

On December 13, 1993, the FAA

issued AD 93–25–06, amendment 39–

8772 (58 FR 69221, December 30, 1993),

applicable to certain Boeing Model 767

series airplanes equipped with overwing escape slides, to require

modification of the trailing edge panels

and the aft flaps. That action was

prompted by the results of functional

tests of over-wing escape slides, which

revealed that some slides were damaged

when they were deployed across sharp

corners on the trailing edge of the wing

and the large gaps between the trailing

edge panels of the wing. The actions

required by that AD are intended to

prevent damage to the over-wing escape

slide, which could hinder inflation of

the slide to a usable configuration

during an emergency evacuation.

Since the issuance of that AD, the

FAA has received a report indicating

that modification of the trailing edge

panels and the aft flaps has not been

accomplished in production on Model

767 series airplanes, equipped with

over-wing escape slides, line positions

477 through 542 inclusive. In light of

this, these additional airplanes are

subject to the same unsafe condition

addressed by AD 93–25–06.

The FAA has reviewed and approved

Boeing Service Bulletin 767–57–0043,

Revision 3, dated February 2, 1995. The

modification procedures described in

this revision are identical to those

described in Revision 2 of the service

bulletin (which was referenced in AD

93–25–06). This revision only expands

the effectivity listing to include

additional airplanes.

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 modification of the

trailing edge panels and the aft flaps.

The applicability of the proposed rule

would be revised to include additional

airplanes. The proposed actions would

be required to be accomplished in

accordance with the service bulletin

described previously.

As a result of recent communications

with the Air Transport Association

(ATA) of America, the FAA has learned

that, in general, some operators may