[Federal Register Volume 76, Number 215 (Monday, November 7, 2011)]
[Proposed Rules]
[Pages 68666-68668]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-28758]
[[Page 68666]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-1171; Directorate Identifier 2011-NM-101-AD]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain The Boeing Company Model 737-100, -200, -200C, and -300 series
airplanes. This proposed AD was prompted by a report from the airplane
manufacturer that airplanes were assembled with air distribution ducts
in the environmental control system (ECS) wrapped with Boeing Material
Specification (BMS) 8-39 or Aeronautical Materials Specifications (AMS)
3570 polyurethane foam insulation, a material with fire-retardant
properties that deteriorate with age. This proposed AD would require
reworking certain air distribution ducts in the ECS. We are proposing
this AD to prevent ignition of the BMS 8-39 or AMS 3570 polyurethane
foam insulation on the duct assemblies of the ECS due to a potential
electrical arc, which could start a small fire and lead to a larger
fire that may spread throughout the airplane through the ECS.
DATES: We must receive comments on this proposed AD by December 22,
2011.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
Fax: (202) 493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC 20590.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone
(206) 544-5000, extension 1; fax (206) 766-5680; email
[email protected]; Internet https://www.myboeingfleet.com. You may
review copies of the referenced service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton,
Washington. For information on the availability of this material at the
FAA, call (425) 227-1221.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this proposed AD, the regulatory
evaluation, any comments received, and other information. The street
address for the Docket Office (phone: (800) 647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
FOR FURTHER INFORMATION CONTACT: Kimberly A. DeVoe, Aerospace Engineer,
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington
98057-3356; phone: (425) 917-6495; fax: (425) 917-6590; email:
[email protected].
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under the ADDRESSES section. Include ``Docket No. FAA-2011-1171;
Directorate Identifier 2011-NM-101-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because of those comments.
We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.
Discussion
We have received reports of duct assemblies in the ECS with burned
BMS 8-39 polyurethane foam insulation on two Model 767-200 series
airplanes. The airplane manufacturer has also notified us that certain
Model 737-100, -200, -200C, and -300 series airplanes were assembled
with duct assemblies in the ECS wrapped with BMS 8-39 or AMS 3570
polyurethane foam insulation. The fire-retardant properties of BMS 8-39
and AMS 3570 polyurethane foam insulation deteriorate with age. This,
along with dust, dirt, and other carbon particulate contamination of
the insulation on the ducts, adds an available fuel source for a
potential fire. Once ignited, the foam insulation emits noxious smoke,
does not self-extinguish, and drips droplets of liquefied polyurethane,
which can further propagate a fire. Because the insulation is wrapped
around the duct assemblies, which are located throughout the airplane,
if the insulation is ignited a fire could potentially travel along the
ducts and spread throughout the airplane. This condition, if not
corrected, could result in ignition of the BMS 8-39 or AMS 3570
polyurethane foam insulation on the duct assemblies of the ECS due to a
potential electrical arc, which could start a small fire and lead to a
larger fire that may spread throughout the airplane through the ECS.
Other Relevant Rulemaking
On January 14, 2008, we issued AD 2008-02-16, Amendment 39-15346
(73 FR 4061, January 24, 2008), applicable to certain Model 767-200 and
767-300 series airplanes.
On June 17, 2010, we issued AD 2010-14-01, Amendment 39-16344 (75
FR 38007, July 1, 2010), applicable to certain Model 747-100, 747-100B,
747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400F,
747SR, and 747SP series airplanes.
AD 2008-02-16, Amendment 39-15346 (73 FR 4061, January 24, 2008),
and AD 2010-14-01, Amendment 39-16344 (75 FR 38007, July 1, 2010),
require reworking certain duct assemblies in the ECS. These ADs
resulted from reports of duct assemblies in the ECS with burned BMS 8-
39 polyurethane foam insulation. These ADs also resulted from reports
from the airplane manufacturer that airplanes were assembled with duct
assemblies in the ECS wrapped with BMS 8-39 polyurethane foam
insulation, a material with fire-retardant properties that deteriorate
with age. We issued these ADs to prevent a potential electrical arc
from igniting the BMS 8-39 polyurethane foam insulation on the duct
assemblies of the ECS, which could propagate a small fire and lead to a
larger fire that might spread throughout the airplane through the ECS.
[[Page 68667]]
Relevant Service Information
We reviewed Boeing Service Bulletin 737-21A1132, Revision 3, dated
February 16, 2011. This service bulletin describes procedures for
reworking and part-marking the following affected duct assemblies ECS
systems. The rework includes doing a pressure and leak test following
installation of the new insulation.
Captain's outlet air distribution ducts
Control cabin air distribution ducts
Distribution manifold
Passenger air distribution gasper air ducts
FAA's Determination
We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under ``Differences Between the Proposed AD and the Service
Information.''
Differences Between the Proposed AD and the Service Information
Boeing Service Bulletin 737-21A1132, Revision 3, dated February 16,
2011, recommends reworking the affected duct assemblies ``during the
next heavy maintenance check, within 24,000 flight-hours from the date
on this service bulletin.'' This proposed AD would require operators to
rework the affected duct assemblies within 72 months after the
effective date of the AD. In developing the compliance time for this
action, we considered the degree of urgency associated with addressing
the subject unsafe condition. We also considered the availability of
required parts and the practical aspect of reworking the affected duct
assemblies within an interval that parallels normal scheduled
maintenance for most affected operators. The average heavy maintenance
schedule for the affected fleet is between 60 and 72 months; therefore,
the proposed compliance time of 72 months is equivalent to the
recommended compliance time of ``during the next heavy maintenance
check, within 24,000 flight-hours,'' and it represents an appropriate
interval in which an ample number of required parts will be available
to modify the affected fleet without adversely affecting the safety of
these airplanes. This difference has been coordinated with the Boeing
Company.
Costs of Compliance
We estimate that this proposed AD affects 292 airplanes of U.S.
registry.
We estimate the following costs to comply with this proposed AD:
Estimated Costs
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Cost on U.S.
Action Labor cost Parts cost Cost per product operators
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Duct assembly rework/part marking 250 work-hours x $85 $3,545 $24,795 $7,240,140
per hour = $21,250.
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Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
Regulatory Findings
We determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect on the States, on the relationship
between the national Government and the States, or on the distribution
of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify 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),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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. The FAA amends Sec. 39.13 by adding the following new
airworthiness directive (AD):
The Boeing Company: Docket No. FAA-2011-1171; Directorate Identifier
2011-NM-101-AD.
(a) Comments Due Date
We must receive comments by December 22, 2011.
(b) Affected ADs
None.
(c) Applicability
This AD applies to The Boeing Company Model 737-100, -200, -
200C, and -300 series airplanes, certificated in any category; as
identified in Boeing Service Bulletin 737-21A1132, Revision 3, dated
February 16, 2011.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 21, Air conditioning.
(e) Unsafe Condition
This AD was prompted by a report from the airplane manufacturer
that airplanes were assembled with air distribution ducts in the
environmental control system (ECS) wrapped with Boeing Material
Specification (BMS) 8-39 or Aeronautical Materials Specifications
(AMS) 3570 polyurethane foam insulation, a material with fire
retardant properties that
[[Page 68668]]
deteriorate with age. We are issuing this AD to prevent ignition of
the BMS 8-39 or AMS 3570 polyurethane foam insulation on the duct
assemblies of the ECS due to a potential electrical arc, which could
start a small fire and lead to a larger fire that may spread
throughout the airplane through the ECS.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Air Distribution Duct Rework
Within 72 months after the effective date of this AD, rework the
applicable duct assemblies in the ECS specified in and in accordance
with the Accomplishment Instructions and Appendix A of Boeing
Service Bulletin 737-21A1132, Revision 3, dated February 16, 2011.
Note 1: The service bulletin accomplishment instructions might
refer to other procedures. When the words ``refer to'' are used and
the operator has an accepted alternative procedure, the accepted
alternative procedure can be used to comply with the AD. When the
words ``in accordance with'' are included in the instruction, the
procedure in the design approval holder document must be used to
comply with the AD.
(h) Credit for Actions Accomplished in Accordance With Previous Service
Information
Reworking the applicable duct assemblies in the ECS in
accordance with the Accomplishment Instructions and Appendix A of
Boeing Service Bulletin 737-21A1132, Revision 2, dated June 13,
2007, before the effective date of this AD is acceptable for
compliance with the corresponding actions required by paragraph (g)
of this AD.
(i) Parts Installation
As of the effective date of this AD, no person may install an
ECS duct assembly with BMS 8-39 or AMS 3570 polyurethane foam
insulation on any airplane.
(j) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. In accordance with 14
CFR 39.19, send your request to your principal inspector or local
Flight Standards District Office, as appropriate. If sending
information directly to the manager of the ACO, send it to the
attention of the person identified in the Related Information
section of this AD. Information may be emailed to: 9-ANM&-Seattle-ACO-Requests-faa.gov.
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.
(k) Related Information
(1) For more information about this AD, contact Kimberly A.
DeVoe, Aerospace Engineer, Cabin Safety and Environmental Systems
Branch, ANM-150S, FAA, Seattle Aircraft Certification Office, 1601
Lind Avenue SW., Renton, Washington 98057-3356; phone: (425) 917-
6495; fax: (425) 917-6590; email: [email protected].
(2) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; phone:
(206) 544-5000, extension 1; fax: (206) 766-5680; email:
[email protected]; Internet: https://www.myboeingfleet.com. You
may review copies of the referenced service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton,
Washington. For information on the availability of this material at
the FAA, call (425) 227-1221.
Issued in Renton, Washington, on October 26, 2011.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-28758 Filed 11-4-11; 8:45 am]
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