[Federal Register Volume 64, Number 155 (Thursday, August 12, 1999)]
[Proposed Rules]
[Pages 43966-43969]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-20940]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-161-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-9-80 and MD-
90-30 Series Airplanes, and Model MD-88 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 certain McDonnell Douglas Model 
DC-9-80 and MD-90-30 series airplanes, and Model MD-88 airplanes. This 
proposal would require that a determination be made of whether, and at 
what locations, metallized polyethyleneteraphthalate (MPET) insulation 
blankets are installed, and replacement of MPET insulation blankets 
with new insulation blankets. This proposal is prompted by reports of 
in-flight and ground fires on certain airplanes manufactured with 
insulation blankets covered with MPET, which may contribute to the 
spread of a fire when ignition occurs from small ignition sources such 
as electrical arcing or sparking. The actions specified by the proposed 
AD are intended to ensure that insulation blankets constructed of MPET 
are removed from the fuselage. Such insulation blankets could propagate 
a small fire that is the result of an otherwise harmless electrical arc 
and could lead to a much larger fire.

DATES: Comments must be received by September 27, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-161-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00

[[Page 43967]]

p.m., Monday through Friday, except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Aircraft Group, Long Beach 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: Robert Stacho, 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) 627-5334; 
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 99-NM-161-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. 99-NM-161-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports of a number of in-flight and ground 
fires on McDonnell Douglas Model DC-9-80 and MD-11 series airplanes 
manufactured with insulation blankets covered with metallized 
polyethyleneteraphthalate (MPET) (also known as metallized Mylar). 
Investigation has revealed that MPET covered insulation blankets may 
contribute to the spread of a fire when ignition occurs from small 
ignition sources such as electrical arcing or sparking. The results of 
extensive flammability testing, conducted by the manufacturer and the 
FAA, revealed that this type of insulation material will propagate a 
fire.
    There are other materials on insulation blankets that exhibit 
similar flammability characteristics if ignited. However, these 
materials are much more difficult to ignite than MPET.
    Insulation blankets constructed of MPET installed throughout the 
fuselage, if not corrected, could propagate a small fire that is the 
result of an otherwise harmless electrical arc and could lead to a much 
larger fire.
    The subject insulation blankets on certain McDonnell Douglas Model 
MD-90-30 and DC-10 series airplanes, and Model MD-88 airplanes are 
identical to those on the affected Model DC-9-80 and MD-11 series 
airplanes. Therefore, all of these airplanes may be subject to the same 
unsafe condition. The FAA is issuing a separate rulemaking action 
[notice of proposed rulemaking (NPRM), Rules Docket No. 99-NM-162-AD] 
to address McDonnell Douglas Model DC-10 and MD-11 series airplanes.

Other Relevant Investigations and Rulemaking

    The FAA is continuing to investigate various wiring problems on 
McDonnell Douglas Model DC-9-80, MD-90-30, DC-10, and MD-11 series 
airplanes, and Model MD-88 airplanes. The FAA may consider additional 
rulemaking actions to address any identified unsafe condition. The FAA 
will take into account the impact of those actions on U.S. operators to 
minimize the duplication of aircraft downtime associated with 
accomplishing the actions of this proposed AD.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletin MD-90-25-015, Revision 01, dated November 5, 1997 (for Model 
MD-90-30 series airplanes), and McDonnell Douglas Service Bulletin 
MD80-25-355, Revision 01, dated November 5, 1997 (for Model DC-9-80 
series airplanes and Model MD-88 airplanes). The service bulletins 
describe procedures for replacement of MPET covered insulation blankets 
with new blankets fabricated with metallized Tedlar or equivalent 
blanket material. Accomplishment of the replacement procedures 
specified in the service bulletins is intended to adequately address 
the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    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 require accomplishment of the actions specified in 
the service bulletins described previously, except as discussed below.

Differences Between the Proposed AD and Service Bulletins

    The referenced service bulletins describe procedures for 
replacement of MPET covered insulation blankets with certain metallized 
Tedlar or equivalent blanket material, which meet the current FAA 
flammability standards (i.e., Bunsen burner test). However, this 
proposed AD requires replacement with insulation blankets that are 
constructed of materials tested in accordance with Standard Test Method 
American Society for Testing and Materials (ASTM) E648 and approved by 
the FAA. The FAA finds that the current flammability standards are not 
able to distinguish between different types of insulation covering 
material in their flame spread properties from small ignition sources. 
ASTM E648 provides a test that will differentiate flame spread 
properties of different metallized Tedlars. Only one of the two 
insulation blanket film materials specified in the service bulletins 
has successfully passed the testing of the ASTM flammability standard 
and has been found to be an acceptable replacement material for the 
MPET covered insulation blankets. Other film material, such as certain 
polyimide and fluoropolymer composites, also have been successfully 
tested to ASTM E648 and could be found to be acceptable for compliance 
with the requirements of this proposed AD if presented to the FAA for 
approval. These materials are not listed in the service bulletins 
described previously.

[[Page 43968]]

    Operators should note that this proposed AD would require 
replacement of MPET insulation blankets within 4 years after the 
effective date of this AD. The service bulletins recommend that this 
action should be accomplished ``at the earliest practical maintenance 
period.'' Maintenance periods vary between operators and may involve 
maintenance on an entire airplane or only portions of an airplane. As a 
result, in developing an appropriate compliance time for this and other 
proposed AD's, the FAA must adopt a time period that will apply to all 
operators and airplanes. In establishing a compliance time for this 
proposed AD, the FAA balanced the urgency associated with addressing 
the subject unsafe condition against the need to ensure that operators 
are provided sufficient time to perform a safe replacement of the 
insulation. Because of the close proximity of the insulation to wiring 
and other fixtures of various critical airplane systems, it is 
imperative that operators be given the necessary time to ensure safe 
replacement. Therefore, the FAA has determined that a 4-year compliance 
time is appropriate in that it allows the proposed replacement to be 
accomplished within an interval of time that encompasses normal 
scheduled maintenance for the majority of affected operators, thereby, 
allowing safe replacement. In order to meet the deadline, the FAA 
expects early planning and anticipates that operators will have to take 
advantage of every heavy maintenance opportunity.
    Operators also should note that the effectivity listing of the 
referenced service bulletins differs from the applicability of the 
proposed AD. The applicability of the proposed AD affects airplanes 
manufactured with MPET insulation blankets. The effectivity listing of 
the service bulletins not only includes airplanes manufactured with 
MPET insulation blankets, but airplanes equipped with other materials 
that are much more difficult to ignite than MPET (as discussed 
previously). The FAA has determined that only airplanes manufactured 
with MPET insulation blankets are subject to the identified unsafe 
condition. Therefore, paragraph (a) of the proposed AD would require 
that a determination be made of whether, and at what locations, MPET 
insulation blankets are installed, and the proposal would require 
corrective action only with respect to those blankets. The proposal 
would require that this determination be made in a manner approved by 
the manager of the LAACO. Blankets that are stamped with ``DMS 2072, 
Type 2, Class 1, Grade A'' or ``DMS 1996, Type 1'' are constructed of 
MPET. On some blankets, because of their age or wear, it may not be 
possible to identify these stamps. Boeing is currently developing 
instructions for how to determine whether such blankets are constructed 
of MPET. These instructions, if approved, may be referenced as 
additional service information in any final rule resulting from this 
rulemaking. In addition, if additional airplane models manufactured 
with MPET insulation blankets are identified, the FAA may consider 
additional rulemaking actions to address the identified unsafe 
condition.

Regulatory Evaluation Summary

    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.
    The FAA conducted a Preliminary Cost Analysis and Initial 
Regulatory Flexibility Analysis to determine the regulatory impacts of 
this and one other proposed AD to operators of all 699 U.S.-registered 
McDonnell Douglas airplanes that have thermal/acoustical insulation 
blankets covered with a film of MPET. This analysis is included in the 
Rules Docket No.'s 99-NM-161-AD and 99-NM-162-AD. The FAA has 
determined that 612 Model DC-9-80 series airplanes and 22 Model MD-90-
30 series airplanes operated by 16 entities would be affected by this 
proposed AD. Thirteen of these entities operate N-registered Model DC-
9-80 series airplanes, three entities operate Model MD-90-30 series 
airplanes, and two entities operate both Model DC-9-80 series airplanes 
and Model MD-90-30 series airplanes.
    The Preliminary Cost Analysis and Initial Regulatory Flexibility 
Analysis, completed by the FAA and included in this Rules Docket, 
estimates that the affected airplanes could be retrofitted with 
thermal/acoustic insulation blankets covered with film that exhibit no 
flame propagation when tested in accordance with the requirements of 
ASTM E648 or FAA-approved equivalent. Testing conducted by the FAA 
indicates that there are films that are currently in use that meet the 
test standard required by this proposed AD. These include certain 
polyvinylfluoride films that weigh no more than the materials they 
would replace. The FAA has identified three categories of costs 
associated with the retrofit: (1) Material costs of the blankets; (2) 
labor costs to remove existing blankets, install new blankets, and 
reinstall wiring, panels, floors, and other items; and (3) net lost 
revenues, or out of service costs. Over the four-year compliance 
period, material costs would be $17.2 million, labor costs would be 
$214.1 million, and net lost revenues would be $13.3 million. Total 
costs would be $244.6 million, or $207.0 million discounted to present 
value at seven percent.
    The Regulatory Flexibility Act (RFA) of 1980 establishes ``as a 
principle of regulatory issuance that agencies shall endeavor, 
consistent with the objective of the rule and of applicable statutes, 
to fit regulatory and informational requirements to the sale of the 
business, organizations, and governmental jurisdictions subject to 
regulation. To achieve that principle, the RFA requires agencies to 
solicit and consider flexible regulatory proposals and to explain the 
rationale for their actions. The RFA covers a wide-range of small 
entities, including small businesses, not-for-profit organizations, and 
small governmental jurisdictions.
    Agencies must perform a review to determine whether a proposed or 
final rule will have a significant economic impact on a substantial 
number of small entities. If the determination is that it will, the 
Agency must prepare a regulatory flexibility analysis as described in 
the RFA.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the RFA provides that the 
head of the agency may so certify and a regulatory flexibility analysis 
is not required. The certification must include a statement providing 
the factual basis for this determination, and the reasoning should be 
clear.
    Three of the operators affected by the proposed AD are considered 
small, that is, they employ fewer than 1,500 people. One of these 
operators is a private corporation and the FAA is unable to ascertain 
any financial information about it. The other two entities have 
revenues in excess of $100 million. Two entities are not considered a 
substantial number of small entities by Small Business Administration 
criteria. Pursuant to the RFA, 5 U.S.C. 605(b), the FAA certifies that 
this proposed AD would not have a significant economic impact on a 
substantial number of small entities.

[[Page 43969]]

    The provisions of this proposed AD would have little or no impact 
on trade for U.S. firms doing business in foreign countries and foreign 
firms doing business in the United States.
    Title II of the Unfunded Mandates Reform Act of 1995 (the Act), 
enacted as Pub. L. 104-4 on March 22, 1995, requires each Federal 
agency, to the extent permitted by law, to prepare a written assessment 
of the effects of any Federal mandate in a proposed or final agency 
rule that may result in the expenditure by State, local, and tribal 
governments, in the aggregate, or by the private sector, of $100 
million or more (adjusted annually for inflation) in any one year. 
Section 204(a) of the Act, 2 U.S.C. 1534(a), requires the Federal 
agency to develop an effective process to permit timely input by 
elected officers (or their designees) of State, local, and tribal 
governments on a proposed ``significant intergovernmental mandate.'' A 
``significant intergovernmental mandate'' under the Act is any 
provision in a Federal agency regulation that would impose an 
enforceable duty upon State, local, and tribal governments, in the 
aggregate, of $100 million (adjusted annually for inflation) in any one 
year. Section 203 of the Act, 2 U.S.C. 1533, which supplements section 
204(a), provides that before establishing any regulatory requirements 
that might significantly or uniquely affect small governments, the 
agency shall have developed a plan that, among other things, provides 
for notice to potentially affected small governments, if any, and for a 
meaningful and timely opportunity to provide input in the development 
of regulatory proposals.
    This proposed AD does not contain any Federal intergovernmental or 
private sector mandate. Therefore, the requirements of Title II of the 
Unfunded Mandates Reform Act of 1995 do not apply.

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.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

McDonnell Douglas: Docket 99-NM-161-AD.
    Applicability: Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 
(MD-83), DC-9-87 (MD-87) series airplanes; Model MD-90-30 series 
airplanes; and MD-88 airplanes; manufacturer's fuselage numbers 1011 
through 2241 inclusive; 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 (e) 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 insulation blankets constructed of metallized 
polyethyleneteraphthalate (MPET) are removed from the fuselage, 
accomplish the following:

Inspection

    (a) Within 4 years after the effective date of this AD, 
determine whether, and at what locations, insulation blankets 
constructed of MPET are installed. This determination shall be made 
in a manner approved by the Manager, Los Angeles Aircraft 
Certification Office (ACO), FAA, Transport Airplane Directorate.

    Note 2: Insulation blankets that are stamped with ``DMS 2072, 
Type 2, Class 1, Grade A'' or ``DMS 1996, Type 1'' are constructed 
of MPET.

Corrective Actions

    (b) For insulation blankets that are determined not to be 
constructed of MPET, no further action is required by this AD.
    (c) For insulation blankets that are determined to be 
constructed of MPET, within 4 years after the effective date of this 
AD, replace the MPET insulation blankets with new insulation 
blankets. The replacement procedures shall be done in accordance 
with the Accomplishment Instructions of McDonnell Douglas Service 
Bulletin MD-90-25-015, Revision 01, dated November 5, 1997 (for 
Model MD-90-30 series airplanes); or McDonnell Douglas Service 
Bulletin MD80-25-355, Revision 01, dated November 5, 1997 (for Model 
DC-9-80 series airplanes and Model MD-88 airplanes); as applicable. 
The replacement insulation blankets must be constructed of materials 
tested in accordance with Standard Test Method American Society for 
Testing and Materials (ASTM) E648 and approved by the Manager, Los 
Angeles ACO.

    Note 3: Although this paragraph allows up to 4 years for the 
required replacement, the FAA anticipates that operators will comply 
at the earliest practicable maintenance opportunity.

    Note 4: Only one of the two metallized Tedlar covers specified 
in the service bulletins has been shown to have successfully passed 
the testing of the ASTM flammability standard and is considered 
acceptable for compliance with the requirements of paragraph (c) of 
this AD.

Spares

    (d) As of the effective date of this AD, no person shall install 
an MPET insulation blanket on any airplane.

Alternative Methods of Compliance

    (e) 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 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

    (f) 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 August 9, 1999.
D. L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-20940 Filed 8-11-99; 8:45 am]
BILLING CODE 4910-13-P