
[Federal Register Volume 77, Number 39 (Tuesday, February 28, 2012)]
[Proposed Rules]
[Pages 11789-11791]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-4645]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0186; Directorate Identifier 2011-NM-268-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 737-600, -700, -700C, -800, -900, and 
-900ER series airplanes. This proposed AD was prompted by reports of 
flight crew failure to activate air data probe heat. This proposed AD 
would require modifying the anti-icing system for the angle of attack 
sensor, the total air temperature, and the pitot probes. We are 
proposing this AD to prevent ice from forming on air data system 
sensors and consequent loss of or misleading airspeed indication on all 
airspeed indicating systems, which could lead to loss of control of the 
airplane.

DATES: We must receive comments on this proposed AD by April 13, 2012.

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,

[[Page 11790]]

extension 1; fax 206-766-5680; email me.boecom@boeing.com; 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: Frank Carreras, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington 
98057-3356; phone: 425-917-6442; fax: 425-917-6590; email: 
frank.carreras@faa.gov.

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-2012-0186; 
Directorate Identifier 2011-NM-268-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

    The air data sensor heating system, when ON, heats the pitot probes 
that measure air pressure resulting from the airplane's motion through 
the air in order to provide airspeed indications to the flight crew. 
This heating prevents ice from forming inside the pitot probes, which 
would degrade or block the probes' ability to measure air pressure. The 
pitot heat switch, however, is not always set to ON. Although the 
existing ice protection system provides indication of activation to the 
flight crew, three reported incidents on Model 737 airplanes were 
attributed to failure to activate the air data sensor heating system. 
The affected airplanes do not have an automatic activation of the air 
data sensor heating system; pilots activate the system manually as a 
pretakeoff checklist item. Failure to activate the air data sensor 
heating system could result in ice formation on air data system 
sensors, which could lead to misleading airspeed data or loss of all 
airspeed indicating systems, and loss of control of the airplane.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 737-30A1063, dated 
November 16, 2011. This service bulletin describes procedures for 
modifying the anti-icing system for the angle of attack sensor, the 
total air temperature, and the pitot probes. The modification involves 
the following:
     Changing the wires and replacing the P5-9 window/pitot 
heat module on the P5 overhead panel in the flight compartment (the 
modified P5-9 window/pitot heat module changes the current ON and OFF 
positions of the pitot heat switch to ON and AUTO);
     Replacing two circuit breakers; installing relay supports, 
relays, and decals; and changing wiring at the P18 circuit breaker 
panels in the flight compartment; and
     Changing the wiring at the E2-2 and E3-1 electronics 
shelves in the electrical/electronics compartment.
    These modifications to the air data sensor heating system provide 
automatic activation of the heating system when the modified pitot heat 
switch is set to AUTO and either engine is running.

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.

Costs of Compliance

    We estimate that this proposed AD affects 1,025 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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Modification...................  60 to 79 work-hours x   $4,991 to $7,506.  Up to $14,221....  Up to
                                  $85 per hour = $5,100                                         $14,576,525.
                                  to $6,715.
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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.

[[Page 11791]]

    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-2012-0186; Directorate Identifier 
2011-NM-268-AD.

(a) Comments Due Date

    We must receive comments by April 13, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800, -900, and -900ER series airplanes; certificated in any 
category; as identified in Boeing Alert Service Bulletin 737-
30A1063, dated November 16, 2011.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 3030, Pitot/Static Anti-Ice System.

(e) Unsafe Condition

    This AD was prompted by reports of flight crew failure to 
activate air data probe heat. We are issuing this AD to prevent ice 
from forming on air data system sensors and consequent loss of or 
misleading airspeed indication on all airspeed indicating systems, 
which could lead to loss of control of the airplane.

(f) Compliance

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

(g) Modification

    Within 24 months after the effective date of this AD: modify the 
anti-icing system for the angle of attack sensor, the total air 
temperature, and the pitot probes, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
30A1063, dated November 16, 2011.

(h) 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-AMOC-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.

(i) Related Information

    (1) For more information about this AD, contact Frank Carreras, 
Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, 
Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., 
Renton, Washington 98057-3356; phone: 425-917-6442; fax: 425-917-
6590; email: frank.carreras@faa.gov.
    (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; telephone 
206-544-5000, extension 1; fax 206-766-5680; email 
me.boecom@boeing.com; 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 February 10, 2012.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-4645 Filed 2-27-12; 8:45 am]
BILLING CODE 4910-13-P


