Airworthiness Directives; McDonnell Douglas Model MD-11 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-100-AD; Amendment 39-11154; AD 99-09-51]

RIN 2120-AA64

Airworthiness Directives; McDonnell Douglas Model MD-11 Series

Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment

adopting airworthiness directive (AD) 99-09-51 that was sent previously

to all known U.S. owners and operators of certain McDonnell Douglas

Model MD-11 series airplanes by individual notices. This AD requires

visual inspections under the floorboards in the lower center cargo

compartment at frame 1681 to verify that a certain bracket and a

certain open face nylon clamp are installed to a specific support wire

bundle and to detect damage of the subject wire bundle; repair of

damaged wiring; and installation of certain silicone rubber coated with

a glass cloth protective wrap around the wire bundle, if necessary.

This action is prompted by an incident in which the insulation

[[Page 23180]]

blanket between frames 1661 and 1681 in the lower center cargo

compartment was found to be burnt due to a missing wiring harness

support bracket/clamp on the wire bundle at frame 1681. The actions

specified by this AD are intended to ensure that such a wire harness

support bracket/clamp is installed; a missing bracket/clamp could cause

the wire bundle to chafe against the frame, which could result in

sparks, smoke, and possible fire in the lower center cargo compartment.

DATES: Effective May 5, 1999, to all persons except those persons to

whom it was made immediately effective by emergency AD 99-09-51, issued

on April 16, 1999, which contained the requirements of this amendment.

Comments for inclusion in the Rules Docket must be received on or

before June 29, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-114,

Attention: Rules Docket No. 99-NM-100-AD, 1601 Lind Avenue, SW.,

Renton, Washington 98055-4056.

Information pertaining to this amendment 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.

FOR FURTHER INFORMATION CONTACT: Brett Portwood, Aerospace Engineer,

ANM-130L, FAA, Transport Airplane Directorate, Los Angeles Aircraft

Certification Office, 3960 Paramount Boulevard, Lakewood, California

90712; telephone (562) 627-5350; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: On April 16, 1999, the FAA issued emergency

AD 99-09-51, which is applicable to certain McDonnell Douglas Model MD-

11 series airplanes.

As part of its practice of re-examining all aspects of the service

experience of a particular aircraft whenever an accident occurs, the

FAA has become aware of an incident in which the insulation blanket

between frames 1661 and 1681 in the lower center cargo compartment was

found to be burnt. This incident occurred on a McDonnell Douglas Model

MD-11 series airplane.

Investigation revealed that a wiring harness (including wires with

a 115 volt alternating current) of the aft cargo loader control unit

was contacting the insulation blanket and rubbing against frame 1681

above stringer R46. A wire was cut, and three other wires were missing

insulation. In addition, frame 1681 had signs of arcing damage.

Furthermore, the exposed moisture barrier material of the insulation

blanket was burnt, and a hole was detected on the insulation blanket

where the wiring harness was chafing against frame 1681. Further

investigation revealed that a wiring harness support bracket/clamp on

the wire bundle at frame 1681 may not have been installed during

production of the airplane.

This incident is not considered to be related to an accident that

occurred off the coast of Nova Scotia involving a McDonnell Douglas

Model MD-11 series airplane. The cause of that accident is still under

investigation.

A missing wiring harness support bracket/clamp on the wire bundle

at frame 1681 could cause the wire bundle to chafe against the frame,

which could result in sparks, smoke, and possible fire in the lower

center cargo compartment.

Other Related Rulemaking

On April 9, 1999, the FAA issued a similar action (AD 99-08-51),

which applies only to airplanes that are equipped with a 72-inch cargo

door and use the light-weight cargo handling system. However, since the

issuance of AD 99-08-51, the FAA has determined that the wire routing

on airplanes that are equipped with a 72-inch cargo door and use any

cargo handling system must also be inspected. Therefore, the FAA has

determined that these additional airplanes also are subject to the

unsafe condition identified in AD 99-08-51, and that the actions

required by that AD must be accomplished on those airplanes to ensure

an adequate level of safety of the affected fleet. Those airplanes are

listed in the applicability of this new AD.

The FAA, in conjunction with Boeing and operators of Model MD-11

series airplanes, is continuing to review all aspects of the service

history of those airplanes to identify potential unsafe conditions and

to take appropriate corrective actions. This airworthiness directive is

one of a series of actions identified during that process. The process

is continuing and the FAA may consider additional rulemaking actions as

further results of the review become available.

Explanation of Requirements of the Rule

Since an unsafe condition has been identified that is likely to

exist or develop on other airplanes of this same type design, this

airworthiness directive is issued to require a visual inspection to

verify that, under the floorboards in the lower center cargo

compartment at frame 1681, a certain bracket and a certain open face

nylon clamp are installed to a specific support wire bundle. This AD

also requires a visual inspection to detect damage of the subject wire

bundle; repair of damaged wiring; and installation of certain silicone

rubber coated with a glass cloth protective wrap around the subject

wire bundle, if necessary. In addition, this AD requires that operators

submit a report of the inspection results to the FAA. The repairs are

required to be accomplished in accordance with the procedures specified

in Chapter 20-30-01 of the McDonnell Douglas MD-11 Airplane Maintenance

Manual, and Chapter 20-10-01 of the McDonnell Douglas MD-11 Wiring

Diagram Manual.

Since it was found that immediate corrective action was required,

notice and opportunity for prior public comment thereon were

impracticable and contrary to the public interest, and good cause

existed to make the AD effective immediately by individual notices

issued on April 16, 1999, to all known U.S. owners and operators of

certain McDonnell Douglas Model MD-11 series airplanes. These

conditions still exist, and the AD is hereby published in the Federal

Register as an amendment to section 39.13 of the Federal Aviation

Regulations (14 CFR 39.13) to make it effective to all persons.

Comments Invited

Although this action is in the form of a final rule that involves

requirements affecting flight safety and, thus, was not preceded by

notice and an opportunity for public comment, comments are invited on

this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All

communications received on or before the closing date for comments will

be considered, and this rule may be amended in light of the comments

received. Factual information that supports the commenter's ideas and

suggestions is extremely helpful in evaluating the effectiveness of the

AD action and determining whether additional rulemaking action would be

needed.

Comments are specifically invited on the overall regulatory,

economic, environmental, and energy aspects of the rule that might

suggest a need to modify the rule. All comments

[[Page 23181]]

submitted will be available, both before and after the closing date for

comments, in the Rules Docket for examination by interested persons. A

report that summarizes each FAA-public contact concerned with the

substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments

submitted in response to this rule must submit a self-addressed,

stamped postcard on which the following statement is made: ``Comments

to Docket Number 99-NM-100-AD.'' The postcard will be date stamped and

returned to the commenter.

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.

The FAA has determined that this regulation is an emergency

regulation that must be issued immediately to correct an unsafe

condition in aircraft, and that it is not a ``significant regulatory

action'' under Executive Order 12866. It has been determined further

that this action involves an emergency regulation under DOT Regulatory

Policies and Procedures (44 FR 11034, February 26, 1979). If it is

determined that this emergency regulation otherwise would be

significant under DOT Regulatory Policies and Procedures, a final

regulatory evaluation will be prepared and placed in the Rules Docket.

A copy of it, if filed, may be obtained from 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.

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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

99-09-51 McDonnell Douglas: Amendment 39-11154. Docket 99-NM-100-

AD.

Applicability: Model MD-11 series airplanes, certificated in any

category; having the following fuselage/factory serial numbers:

------------------------------------------------------------------------

Fuselage No. Serial No.

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447........................................................ 48401

448........................................................ 48402

449........................................................ 48458

453........................................................ 48411

454........................................................ 48412

455........................................................ 48449

456........................................................ 48407

457........................................................ 48408

461........................................................ 48495

466........................................................ 48416

467........................................................ 48417

470........................................................ 48459

475........................................................ 48461

476........................................................ 48434

478........................................................ 48435

479........................................................ 48450

484........................................................ 48484

486........................................................ 48499

488........................................................ 48413

491........................................................ 48414

492........................................................ 48489

493........................................................ 48500

495........................................................ 48410

496........................................................ 48496

497........................................................ 48460

501........................................................ 48418

502........................................................ 48485

505........................................................ 48451

506........................................................ 48437

509........................................................ 48486

512........................................................ 48497

515........................................................ 48514

516........................................................ 48523

517........................................................ 48547

518........................................................ 48468

519........................................................ 48469

520........................................................ 48502

521........................................................ 48548

523........................................................ 48404

524........................................................ 48405

525........................................................ 48518

528........................................................ 48503

529........................................................ 48512

533........................................................ 48538

539........................................................ 48519

541........................................................ 48520

450........................................................ 48419

451........................................................ 48420

452........................................................ 48421

462........................................................ 48505

469........................................................ 48487

480........................................................ 48472

481........................................................ 48473

482........................................................ 48481

483........................................................ 48436

485........................................................ 48474

489........................................................ 48475

499........................................................ 48490

503........................................................ 48491

504........................................................ 58527

507........................................................ 48528

510........................................................ 48476

511........................................................ 48477

513........................................................ 48501

514........................................................ 48478

522........................................................ 48498

526........................................................ 48550

527........................................................ 48551

530........................................................ 48552

531........................................................ 48553

535........................................................ 48554

536........................................................ 48479

537........................................................ 48596

538........................................................ 48480

540........................................................ 48597

550........................................................ 48598

------------------------------------------------------------------------

Note 1: This AD only affects Model MD-11 series airplanes

equipped with a 72-inch cargo door. Model MD-11 series airplanes

equipped with a 104-inch cargo door are not subject to the unsafe

condition addressed by this AD due to the configuration of the wire

bundles.

Note 2: 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 (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 a wire harness support bracket/clamp is installed

on the wire bundle at frame 1681, accomplish the following:

(a) Within 5 days after the effective date of this AD: Perform a

one-time visual inspection under the floorboards in the lower center

cargo compartment at frame 1681 (approximately one inch outboard of

longeron R46) to verify that a bracket having part number P/N

9D0062-3-16-24 (or equivalent), and an open face nylon clamp having

P/N NMC1001-1 or 383-1 (see Figure 1, Item 14/267), are installed to

support wire bundle No. AGS9110. (The nylon clamp specified in this

paragraph may be a larger size, depending on the size of the wire

bundle.)

(1) If the bracket and clamp are installed: Prior to further

flight, perform a visual inspection to detect damage of the subject

wire bundle. If any damage is detected, prior to further flight,

accomplish paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.

(i) Repair in accordance with Chapter 20-30-01 of the McDonnell

Douglas MD-11 Airplane Maintenance Manual. And

(ii) Install a silicone rubber coated with a glass cloth

protective wrap [Douglas Material Specification (DMS) 2109 or

equivalent] around the wire bundle(s) in the area over frame 1681

above stringer R46 in accordance with Chapter 20-10-01 of the

McDonnell Douglas MD-11 Wiring Diagram Manual.

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(2) If the bracket or clamp is not installed: Prior to further

flight, perform a visual inspection to detect damage (i.e., chafing,

damage, or missing wire insulation) of the subject wire bundle(s).

(i) If no damage is detected: Prior to further flight, install a

silicone rubber coated with a glass cloth protective wrap (DMS 2109

or equivalent) around the wire bundle(s) in the area over frame 1681

above stringer R46 in accordance with Chapter 20-10-01 of the

McDonnell Douglas MD-11 Wiring Diagram Manual.

(ii) If any damage is detected: Prior to further flight,

accomplish the actions required by paragraphs (a)(1)(i) and

(a)(1)(ii) of this AD.

(b) Within 10 days after accomplishing the inspection required

by paragraphs (a) and (a)(1) of this AD, submit a report of the

inspection results (both positive and negative findings) to the

Manager, Los Angeles Aircraft Certification Office (ACO), FAA,

Transport Airplane Directorate, 3960 Paramount Boulevard, Lakewood,

California 90712-4137; fax (562) 627-5210. Information collection

requirements contained in this regulation have been approved by the

Office of Management and Budget (OMB) under the provisions of the

Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have

been assigned OMB Control Number 2120-0056.

(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 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.

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) This amendment becomes effective on May 5, 1999, to all

persons except those persons to whom it was made immediately

effective by emergency AD 99-09-51, issued on April 16, 1999, which

contained the requirements of this amendment.

BILLING CODE 4910-13-P

[[Page 23183]]

[GRAPHIC] [TIFF OMITTED] TR30AP99.011

Issued in Renton, Washington, on April 23, 1999.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 99-10815 Filed 4-29-99; 8:45 am]

BILLING CODE 4910-13-C