[Federal Register Volume 86, Number 196 (Thursday, October 14, 2021)]
[Proposed Rules]
[Pages 57081-57083]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-22252]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0794; Project Identifier AD-2021-00400-T]
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: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain The Boeing Company Model 747-400, -400D, and -400F series 
airplanes. This proposed AD was prompted by reports of burned Boeing 
Material Specification (BMS) 8-39 urethane foam, and a report from the 
airplane manufacturer that airplanes were assembled with seals 
throughout various areas of the airplane (including flight deck and 
cargo compartments) made of BMS 8-39 urethane foam, a material with 
fire-retardant properties that deteriorate with age. This proposed AD 
would require replacing the system tube/wire seals made of BMS 8-39 
urethane foam in certain areas of the airplane. The FAA is proposing 
this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by November 
29, 2021.

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 https://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 NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet https://www.myboeingfleet.com. You may 
view this service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 2200 South 216th St., Des Moines, 
WA. For information on the availability of this material at the FAA, 
call 206-231-3195. It is also available at https://www.regulations.gov 
by searching for and locating Docket No. FAA-2021-0794.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0794; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this NPRM, any comments 
received, and other information. The street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Julie Linn, Aerospace Engineer, Cabin 
Safety and Environmental Systems Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3684; 
email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0794; Project Identifier 
AD-2021-00400-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to Julie 
Linn, Aerospace Engineer, Cabin Safety and Environmental Systems 
Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 
98198; phone and fax: 206-231-3684; email: [email protected]. Any 
commentary that the FAA receives which is not specifically designated 
as CBI will be placed in the public docket for this rulemaking.

Background

    The FAA has received reports of burned BMS 8-39 urethane foam, and 
a report from the airplane manufacturer that airplanes were assembled 
with seals throughout various areas of the airplane (including flight 
deck and cargo compartments) made of BMS 8-39 urethane foam, a material 
with fire-retardant properties that deteriorate with age. The fire 
retardants in BMS 8-39 urethane foam are mixed into, but are not 
chemically connected with, the remaining components of the foam, which 
causes the fire retardants to have decreased fire resistance over time. 
The degraded material can be an unacceptable fuel source for a fire if 
exposed to an ignition source. This condition, if not addressed, could 
result in failure of the urethane seals to maintain sufficient Halon 
concentrations in the cargo compartments to extinguish or contain fire 
or smoke, and to prevent penetration of fire or smoke in areas of the 
airplane that are difficult to access

[[Page 57082]]

for fire and smoke detection or suppression.

Related AD

    The FAA issued AD 2013-11-04, Amendment 39-17464 (78 FR 33193, June 
4, 2013) (AD 2013-11-04), which applies to certain The Boeing Company 
Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200F, 747-300, 
747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes; Model 
767-200, -300, -300F, and -400ER series airplanes; and Model 777-200, -
200LR, -300, and -300ER series airplanes. AD 2013-11-04 requires 
replacing certain seals made of BMS 8-39 urethane foam. AD 2013-11-04 
was prompted by operator or in-service reports of burned BMS 8-39 
urethane foam, and a report from the airplane manufacturer indicating 
that airplanes were assembled, throughout various areas of the airplane 
(including flight deck and cargo compartments), with seals made of BMS 
8-39 urethane foam, a material with fire-retardant properties that 
deteriorate with age.

Actions Since AD 2013-11-04 Was Issued

    Since AD 2013-11-04 was issued, the FAA has determined that 
additional replacements of system tube/wire seals made of BMS 8-39 
urethane foam are necessary for certain Model 747-400, -400D, and -400F 
series airplanes. These new proposed actions apply only to certain 
airplanes and would not replace or terminate the actions required by AD 
2013-11-04.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Special Attention Service Bulletin 747-25-
3381, Revision 3, dated February 19, 2021. This service information 
specifies procedures for replacing BMS 8-39 urethane foam seals with 
BMS 1-68 silicone foam rubber seals (including doing a general visual 
inspection of the foam for any tube or wire penetrations and sealing 
any penetrations that go through the insulation blankets). This service 
information adds the work instructions for Group 11, Configuration 2; 
Group 13 and 14, Configuration 4; and Group 16, 17, and 19, 
Configuration 5 airplanes.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information already described. For information on the 
procedures and compliance times, see this service information at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0794.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 131 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
            Action                  Labor cost      Parts cost     Cost per  product      Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Replacement (including GVI)...  Up to 32 work-             $ *  Up to $2,720...........  Up to $356,320.
                                 hours x $85 per
                                 hour = Up to
                                 $2,720.
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* The FAA has received no definitive data on which to base the parts cost estimates for this proposed AD.

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.
    The FAA is 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

    The FAA 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) Would not affect intrastate aviation in Alaska, and
    (3) Would 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

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

The Boeing Company: Docket No. FAA-2021-0794; Project Identifier AD-
2021-00400-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 29, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 747-400, -400D, and 
-400F series airplanes, certificated in any category,

[[Page 57083]]

identified as Group 11, Configuration 2; Group 13 and 14, 
Configuration 4; and Group 16, 17, and 19, Configuration 5, in 
Boeing Special Attention Service Bulletin 747-25-3381, Revision 3, 
dated February 19, 2021.

(d) Subject

    Air Transport Association (ATA) of America Code 25, Equipment/
Furnishings.

(e) Unsafe Condition

    This AD was prompted by reports of burned Boeing Material 
Specification (BMS) 8-39 urethane foam, and a report from the 
airplane manufacturer that airplanes were assembled with seals 
throughout various areas of the airplane (including flight deck and 
cargo compartments) made of BMS 8-39 urethane foam, a material with 
fire-retardant properties that deteriorate with age. The FAA is 
issuing this AD to prevent failure of the urethane seals to maintain 
sufficient Halon concentrations in the cargo compartments to 
extinguish or contain fire or smoke, and to prevent penetration of 
fire or smoke in areas of the airplane that are difficult to access 
for fire and smoke detection or suppression.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) BMS 8-39 Urethane Foam Seal Replacements

    Within 72 months after the effective date of this AD: Replace 
the BMS 8-39 urethane foam seals in the forward cargo compartment 
system tube/wire (including doing a general visual inspection of the 
foam for any tube or wire penetrations and sealing any penetrations 
that go through the insulation blankets) with BMS 1-68 silicone foam 
rubber seals, as applicable, in accordance with the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 747-25-
3381, Revision 3, dated February 19, 2021.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO Branch, 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 responsible Flight Standards Office, 
as appropriate. If sending information directly to the manager of 
the certification office, send it to the attention of the person 
identified in Related Information. Information may be emailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by The Boeing Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO Branch, FAA, to make those findings. To be approved, the repair 
method, modification deviation, or alteration deviation must meet 
the certification basis of the airplane, and the approval must 
specifically refer to this AD.

(i) Related Information

    (1) For more information about this AD, contact Julie Linn, 
Aerospace Engineer, Cabin Safety and Environmental Systems Section, 
FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; 
phone and fax: 206-231-3684; email: [email protected].
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Airworthiness Products Section, Operational 
Safety Branch, 2200 South 216th St., Des Moines, WA. For information 
on the availability of this material at the FAA, call 206-231-3195.

    Issued on September 16, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-22252 Filed 10-13-21; 8:45 am]
BILLING CODE 4910-13-P


