55730 Federal Register / Vol. 62, No. 208 / Tuesday, October 28, 1997 / Rules and Regulations

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96–NM–95–AD; Amendment

39–10176; AD 97–22–05]

RIN 2120–AA64

Airworthiness Directives; McDonnell

Douglas Model DC–9 Series Airplanes

and C–9 (Military) Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule.

SUMMARY: This amendment adopts a

new airworthiness directive applicable

to certain McDonnell Douglas Model

DC–9 series airplanes and C–9 (military)

series airplanes, that requires

modification of the emergency internal

release system of the tailcone and the

accessory compartment. This

amendment is prompted by a report

that, due to failure of the tailcone

release system, the tailcone did not

deploy on an airplane during an

emergency evacuation. The actions

specified by this AD are intended to

ensure that the emergency internal

release system of the tailcone performs

its intended function in the event of an

emergency evacuation. The actions also

are intended to prevent people on board

the airplane from striking their heads on

exposed metal frames in the tailcone

area, which could cause injury and

delay or impede their evacuation during

an emergency.

DATES: Effective December 2, 1997.

The incorporation by reference of

certain publications listed in the

regulations is approved by the Director

of the Federal Register as of December

2, 1997.

ADDRESSES: The service information

referenced in this AD 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 Federal

Aviation Administration (FAA),

Transport Airplane Directorate, Rules

Docket, 1601 Lind Avenue, SW.,

Renton, Washington; or at the FAA,

Transport Airplane Directorate, Los

Angeles Aircraft Certification Office,

3960 Paramount Boulevard, Lakewood,

California; or at the Office of the Federal

Register, 800 North Capitol Street, NW.,

suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Albert H. Lam, Aerospace Engineer,

Systems and Equipment Branch, ANM–

130L, FAA, Los Angeles Aircraft

Certification Office, 3960 Paramount

Boulevard, Lakewood, California 90712;

telephone (562) 627–5346; fax (562)

627–5210.

SUPPLEMENTARY INFORMATION: A

proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) to

include an airworthiness directive (AD)

that is applicable to certain McDonnell

Douglas Model DC–9 series airplanes

and C–9 (military) series airplanes was

published in the Federal Register on

September 13, 1996 (61 FR 48433). That

action proposed to require modification

of the emergency internal release system

of the tailcone and the accessory

compartment.

Interested persons have been afforded

an opportunity to participate in the

making of this amendment. Due

consideration has been given to the

comments received.

Two commenters support the

proposed rule.

Requests To Revise the Compliance

Times of the Proposed Modifications

One commenter requests that the

compliance time for accomplishing the

proposed modifications be extended

from the proposed 36 months to 4 years.

The commenter states that such an

extension will allow the modifications

to be accomplished during a regularly

scheduled heavy maintenance check

and will allow time for procurement of

additional modification kits. The

commenter also states that such an

extension will allow time for revising

the affected manual; training of

inspection and maintenance personnel;

drafting, checking, and approving

engineering documents; and testing and

debugging the proposed modifications.

Another commenter requests that the

compliance times be shortened to 12

months. This commenter suggests that

the proposed compliance times may be

too long to fly with the potential of

failure of the emergency internal release

system of the tailcone.

The FAA does not concur with either

of these commenters’ request. In

developing an appropriate compliance

time for these modifications, the FAA

considered not only the degree of

urgency associated with addressing the

unsafe condition, but the availability of

required parts and the practical aspect

of installing the required modifications

within an interval of time that parallels

normal scheduled maintenance for the

majority of affected operators. The

manufacturer has advised that an ample

number of required parts will be

available for modification of the U.S.

fleet within the proposed compliance

period. Further, the FAA estimates that

the affected airplanes will undergo two

heavy maintenance checks during the

proposed compliance time. In addition,

the FAA finds that the 36-month

compliance time is sufficient for

operators to train their personnel and to

incorporate the modifications into

various documents. However, under the

provisions of paragraph (c) of the final

rule, the FAA may approve requests for

adjustments to the compliance time if

data are presented to justify such an

adjustment.

Request To Remove Modification

Requirement

Two commenters state that the

modification specified in McDonnell

Douglas DC–9 Service Bulletin 53–257,

Revision 1, dated February 9, 1996

[which is referenced in paragraph (a) of

the proposal as the appropriate source

of service information] is difficult to

accomplish and only adds more

problems to the existing tailcone release

system. One of these commenters

contends that the tailcone release

system described in the referenced

service bulletin is unacceptable for an

emergency exit system. This commenter

also contends that the subject

modification cannot be accomplished

on airplanes equipped with aft ventral

airstairs.

From these comments, the FAA infers

that the commenters are requesting that

the proposed modification in paragraph

(a) of the AD be removed from the final

rule. The FAA does not concur. The

FAA acknowledges that there were

some problems associated with

accomplishing the modification in

accordance with the original issue of

McDonnell Douglas DC–9 Service

Bulletin 53–257, dated May 18, 1994.

However, the FAA finds that these

problems were addressed and corrected

in Revision 1 of this service bulletin.

The FAA recognizes that Revision 1 of

the service bulletin does not address

airplanes on which the aft ventral

airstair handle has not been deactivated.

However, based on a survey conducted

by McDonnell Douglas, the FAA finds

that affected operators are willing to

deactivate the aft ventral airstair handle

to accommodate the modification

required by this AD. In addition,

paragraph (c) of the AD contains a

provision for requesting approval of an

alternative method of compliance to

address these types of unique

circumstances.

Request To Add a New Requirement

One commenter requests that

paragraph (b) of the proposed AD be

revised to include procedures for adding
Federal Register / Vol. 62, No. 208 / Tuesday, October 28, 1997 / Rules and Regulations 55731

protective padding between the added

ceiling panel and beams, and on all

other beams in the path of exiting

passengers. The commenter contends

that installation of ceiling panels [as

required by paragraph (b) of the AD]

provides a false sense of security and

guidance to the flight attendants and

evacuees. The commenter states that the

ceiling panels could be damaged easily

by tall and/or unruly passengers during

emergency egress, which could expose

the beams and supporting structure.

Thus other passengers could strike their

heads against the overhead beams. The

commenter also states that the ceiling

panels could detach from its support

structure during an actual emergency,

and consequently, also allow exposure

of the beams and supporting structure.

Further, the commenter states that the

ceiling panels could fall in the path of

the passengers that are exiting from the

airplane. The FAA does not concur. The

FAA has determined that installation of

ceiling panels on the lower side of three

frames and installation of a protective

pad on the last frame in the aft

accessory compartment provides an

acceptable level of safety. In addition,

the FAA finds that such an installation

is comparable to other panel

installations throughout the airplane.

However, under provisions of paragraph

(c) of the final rule, operators may apply

for approval of an alternative methods

of compliance if sufficient justification

is presented to the FAA.

Request To Address Deficiencies With

Existing Tailcone Release System

One commenter states that the

existing tailcone release system contains

many design and reliability deficiencies.

The commenter points out that the

proposed AD does not specify any

requirements to replace or repair the

existing tailcone release system. The

commenter also contends that, due to

such deficiencies, the new interior

release handle [installed in accordance

with the requirements of paragraph (b)

of the proposed AD] will fail to perform

its intended function. From this

comment, the FAA infers that the

commenter is requesting that the FAA

address the problems associated with

the existing tailcone release system in

the proposed AD. The FAA does not

concur. The FAA has previously issued

several other AD’s that concern the

tailcone deployment system on Model

DC–9 series airplanes, which was

discussed previously in the Other

Relevant Rulemaking Section in the

preamble to the NPRM. Therefore, the

FAA finds no change to the final rule is

necessary.

Request To Revise the Proposed

Modification of the Emergency Internal

Release System

One commenter requests that the

existing tailcone release system be

replaced with an electro-mechanical

system, which can be actuated from

inside the airplane. The commenter

states that it is more cost effective to

install a modern and efficient system

(i.e., electro-mechanical system), rather

than a system with design technology

standards that are 25 to 30 years old.

The commenter also states that the

existing system does not meet industry

expectations. The FAA does not concur.

The modification required by paragraph

(b) of this AD was developed with

operator, manufacturer, and FAA

concurrence based on cost and technical

feasibility. However, under the

provisions of paragraph (c) of this AD,

operators may apply for the approval of

an alternative method of compliance, if

sufficient justification is presented to

the FAA.

Request To Revise Various

Manufacturer Manuals

One commenter requests that the FAA

require the manufacturer, rather than

the affected operator(s), to update the

affected Illustrated Parts Catalog,

Airplane Maintenance Manual,

Structural Repair Manual, and Wiring

Diagram Manual to ensure continued

airworthiness of the tailcone release

system. The commenter states that an

operator, who does not have

‘‘experience’’ with the modification

required by the proposed AD, could

enter erroneous information into these

manuals. The FAA does not concur. The

FAA finds that the subject service

documents are not necessary to

accomplish the modifications required

by this AD. The FAA has been informed

that the manufacturer is in the process

of revising the DC–9 Airplane

Maintenance Manual (AMM) to comply

with the continued airworthiness

requirements and will make the AMM

available to operators.

FAA’s Conclusion

After careful review of the available

data, including the comments noted

above, the FAA has determined that air

safety and the public interest require the

adoption of the rule as proposed.

Cost Impact

There are approximately 878

McDonnell Douglas Model DC–9 series

airplanes and C–9 (military) series

airplanes of the affected design in the

worldwide fleet. The FAA estimates that

590 airplanes of U.S. registry will be

affected by this AD.

The modification of the emergency

internal release system will take

approximately 7 work hours per

airplane to accomplish, at an average

labor rate of $60 per work hour.

Required parts will cost approximately

$6,660 per airplane. Based on these

figures, the cost impact of this

modification required by this AD on

U.S. operators is estimated to be

$4,177,200, or $7,080 per airplane.

The modification of the accessory

compartment will take approximately

10 work hours per airplane to

accomplish, at an average labor rate of

$60 per work hour. For the 395

airplanes identified as ‘‘Group I’’ in the

referenced service bulletin, required

parts will cost approximately $1,777 per

airplane. For the 195 airplanes

identified as ‘‘Group 2’’ in the

referenced service bulletin, required

parts will cost $5,369 per airplane.

Based on these figures, the cost impact

of this modification required by this AD

on U.S. operators of Group 1 airplanes

is estimated to be $938,915, or $2,377

per airplane; and on U.S. operators of

Group 2 airplanes is estimated to be

$1,163,955, or $5,969 per airplane.

The cost impact figures discussed

above are based on assumptions that no

operator has yet accomplished any of

the requirements of this AD action, and

that no operator would accomplish

those actions in the future if this AD

were not adopted.

Regulatory Impact

The regulations adopted herein will

not have substantial direct effects on the

States, on the relationship between the

national government and the States, or

on the distribution of power and

responsibilities among the various

levels of government. Therefore, in

accordance with Executive Order 12612,

it is determined that this final rule does

not have sufficient federalism

implications to warrant the preparation

of a Federalism Assessment.

For the reasons discussed above, I

certify that this action (1) is not a

‘‘significant regulatory action’’ under

Executive Order 12866; (2) is not a

‘‘significant rule’’ under DOT

Regulatory Policies and Procedures (44

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

will not have a significant economic

impact, positive or negative, on a

substantial number of small entities

under the criteria of the Regulatory

Flexibility Act. A final evaluation has

been prepared for this action and it is

contained in the Rules Docket. A copy

of it may be obtained from the Rules

Docket at the location provided under

the caption ADDRESSES.
55732 Federal Register / Vol. 62, No. 208 / Tuesday, October 28, 1997 / Rules and Regulations

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation

safety, Incorporation by reference,

Safety.

Adoption of the Amendment

Accordingly, pursuant to the

authority delegated to me by the

Administrator, the Federal Aviation

Administration amends part 39 of the

Federal Aviation Regulations (14 CFR

part 39) as follows:

PART 39—AIRWORTHINESS

DIRECTIVES

1. The authority citation for part 39

continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§39.13 [Amended]

2. Section 39.13 is amended by

adding the following new airworthiness

directive:

97–22–05—McDonnell Douglas: Amendment

39–10176. Docket 96–NM–95–AD.

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

–40, and –50 series airplanes and C–9

(military) series airplanes; as listed in

McDonnell Douglas DC–9 Service Bulletin

53–257, Revision 1, dated February 9, 1996,

and McDonnell Douglas DC–9 Service

Bulletin 25–331, dated December 10, 1993;

operating in a passenger or passenger/cargo

configuration; certificated in any category.

Note 1: The requirements of this AD

become applicable at the time an airplane

operating in an all-cargo configuration is

converted to a passenger or passenger/cargo

configuration.

Note 2: This AD applies to each airplane

identified in the preceding applicability

provision, regardless of whether it has been

otherwise modified, altered, or repaired in

the area subject to the requirements of this

AD. For airplanes that have been modified,

altered, or repaired so that the performance

of the requirements of this AD is affected, the

owner/operator must request approval for an

alternative method of compliance in

accordance with paragraph (c) 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 ensure that the emergency internal

release system of the tailcone performs its

intended function in the event of an

emergency evacuation, accomplish the

following:

(a) For airplanes listed in McDonnell

Douglas DC–9 Service Bulletin 53–257,

Revision 1, dated February 9, 1996: Within

36 months after the effective date of this AD,

modify the emergency internal release system

of the tailcone in accordance with the service

bulletin.

(b) For airplanes listed in McDonnell

Douglas DC–9 Service Bulletin 25–331, dated

December 10, 1993: Within 36 months after

the effective date of this AD, modify the

accessory compartment in accordance with

the service bulletin.

(c) An alternative method of compliance or

adjustment of the compliance time that

provides an acceptable level of safety may be

used if approved by the Manager, Los

Angeles Aircraft Certification Office (ACO),

FAA, Transport Airplane Directorate.

Operators shall submit their requests

through an appropriate FAA Principal

Maintenance Inspector, who may add

comments and then send it to the Manager,

Los Angeles ACO.

Note 3: Information concerning the

existence of approved alternative methods of

compliance with this AD, if any, may be

obtained from the Los Angeles ACO.

(d) 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.

(e) The actions shall be done in accordance

with McDonnell Douglas DC–9 Service

Bulletin 53–257, Revision 1, dated February

9, 1996, and McDonnell Douglas DC–9

Service Bulletin 25–331, dated December 10,

1993. This incorporation by reference was

approved by the Director of the Federal

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

and 1 CFR part 51. Copies may be obtained

from McDonnell Douglas Corporation, 3855

Lakewood Boulevard, Long Beach, California

90846, Attention: Technical Publications

Business Administration, Department C1–

L51 (2–60). Copies may be inspected 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;

or at the Office of the Federal Register, 800

North Capitol Street, NW., suite 700,

Washington, DC.

(f) This amendment becomes effective on

December 2, 1997.

Issued in Renton, Washington, on October

17, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane

Directorate, Aircraft Certification Service.

[FR Doc. 97–28319 Filed 10–27–97; 8:45 am]

BILLING CODE 4910–13–U

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97–NM–229–AD; Amendment

39–10179; AD 97–22–07]

RIN 2120–AA64

Airworthiness Directives; Boeing

Model 737 Series Airplanes

AGENCY: Federal Aviation

Administration, DOT.

ACTION: Final rule; request for

comments.

SUMMARY: This amendment supersedes

an existing airworthiness directive (AD),

applicable to certain Boeing Model 737

series airplanes, that currently requires

repetitive inspections to detect cracking

of the lower skin at the lower row of

fasteners in the lap joints of the

fuselage, and repair of any cracking

detected. This amendment requires that

the inspections be accomplished at

more frequent intervals. This

amendment also adds a requirement for

modification of the fuselage lap joints at

certain locations, which constitutes

terminating action for repetitive

inspections of modified areas. This

amendment is prompted by reports of

numerous fatigue cracks in the lower

skin of the fuselage lap joints at the

lower row of fasteners. The actions

specified in this AD are intended to

prevent such fatigue cracking, which

could result in sudden decompression

of the airplane.

DATES: Effective November 12, 1997.

The incorporation by reference of

certain publications, as listed in the

regulations, is approved by the Director

of the Federal Register as of November

12, 1997.

The incorporation by reference of

Boeing Alert Service Bulletin 737–

53A1177, dated November 8, 1994, as

listed in the regulations, was approved

previously by the Director of the Federal

Register as of December 27, 1994 (59 FR

63716, December 9, 1994).

Comments for inclusion in the Rules

Docket must be received on or before

December 29, 1997.

ADDRESSES: Submit comments in

triplicate to the Federal Aviation

Administration (FAA), Transport

Airplane Directorate, ANM–103,

Attention: Rules Docket No. 97–NM–

229–AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055–4056.

The service information referenced in

this AD 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; or at the Office of

the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Gregory L. Schneider or Nenita K.

Odesa, Aerospace Engineers, Airframe

Branch, ANM–120S, FAA, Transport

Airplane Directorate, Seattle Aircraft

Certification Office (ACO), 1601 Lind

Avenue, SW., Renton, Washington;

telephone (425) 227–2028 or (425) 227–

2557; fax (425) 227–1181.