Document ID: FAA-2014-0603-0013
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Meggitt (Troy), Inc. Combustion Heaters
Posted Date: 2016-11-03T04:00Z

[Federal Register Volume 81, Number 213 (Thursday, November 3, 2016)]
[Proposed Rules]
[Pages 76532-76540]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-26428]

 ========================================================================
 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
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  Federal Register / Vol. 81, No. 213 / Thursday, November 3, 2016 / 
Proposed Rules  

[[Page 76532]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0603; Directorate Identifier 2013-CE-026-AD]
RIN 2120-AA64

Airworthiness Directives; Meggitt (Troy), Inc. Combustion Heaters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening 
of comment period.

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

SUMMARY: We are revising a notice of proposed rulemaking (NPRM) for 
certain Meggitt (Troy), Inc. (previously known as Stewart Warner South 
Wind Corporation and as Stewart Warner South Wind Division) Model 
Series (to include all the variants) 921, 930, 937, 940, 944, 945, 977, 
978, 979, 8240, 8253, 8259, and 8472 combustion heaters that proposed 
to supersede airworthiness directive (AD) 81-09-09. The NPRM proposed 
to retain most actions from AD 81-09-09, add a calendar time to the 
repetitive inspections, add more detailed actions to the inspections, 
and add a pressure decay test. The NPRM was prompted by an airplane 
accident and reports we received of the heater malfunctioning. This 
action revises the NPRM by adding combustion heater models series to 
the applicability and modifying the compliance times. We are proposing 
this SNPRM to correct the unsafe condition on these products. Since 
these actions impose an additional burden over that proposed in the 
NPRM, we are reopening the comment period to allow the public the 
chance to comment on these proposed changes.

DATES: The comment period for the NPRM published in the Federal 
Register on August 20, 2014 (79 FR 49249) is reopened. We must receive 
comments on this SNPRM by December 19, 2016.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Meggitt Control Systems, 3 Industrial Drive, Troy, Indiana 47588; 
telephone: (812) 547-7071; fax: (812) 547-2488; email: 
infotroy@meggitt.com; Internet: www.stewart-warner.com. You may view 
this referenced service information at the FAA, Small Airplane 
Directorate, 901 Locust, Kansas City, Missouri 64106. For information 
on the availability of this material at the FAA, call (816) 329-4148.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2014-
0603; 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: Chung-Der Young, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
2300 East Devon Avenue, Des Plaines, IL 60018-4696; telephone (847) 
294-7309; fax (847) 294-7834 email: chung-der.young@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2014-0603; 
Directorate Identifier 2013-CE-026-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

    On April 16, 1981, we issued AD 81-09-09, Amendment 39-4102 (46 FR 
24936, May 4, 1981) (``AD 81-09-09''), for certain Meggitt (Troy), Inc. 
(previously known as Stewart Warner South Wind Corporation and as 
Stewart Warner South Wind Division) Model Series 8240, 8253, 8259, and 
8472 combustion heaters. AD 81-09-09 resulted from a hazardous 
condition caused by deterioration of the combustion heater. AD 81-09-09 
currently requires repetitive inspections of the combustion heater; 
repetitive installation inspections of the combustion heater; and, for 
combustion heaters having 1,000 hours or more time-in-service (TIS), 
overhaul of the combustion heater.
    We issued a notice of proposed rulemaking (NPRM) to supersede AD 
81-09-09 on August 13, 2014, which published in the Federal Register on 
August 20, 2014 (79 FR 49249). The NPRM was prompted by an airplane 
accident and reports we received of the heater malfunctioning. The NPRM 
proposed to retain most actions from AD 81-09-09, add a calendar time 
to the repetitive inspections, add more detailed actions to the 
inspections, and add a pressure decay test.

Actions Since the NPRM Was Issued

    Since we issued the NPRM, we received comments from the public 
during the comment period that resulted

[[Page 76533]]

in our decision to issue this SNPRM. This SNPRM proposes to increase 
the applicability and modify the compliance time. We also completed an 
initial regulatory flexibility analysis to determine the impact of the 
proposed AD on small entities (this was at the request of one of the 
comments received on the NPRM). Adopted on September 5, 2014, the 
National Transportation Safety Board issued the probable cause for the 
airplane accident that initiated this investigation. The probable cause 
was identified as malfunction of the cabin heater, which resulted in an 
inflight fire and smoke in the airplane.

Comments

    We gave the public the opportunity to comment on the NPRM. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Request To Allow Repair of the Combustion Tube

    James W. Tarter Jr. from Meggitt (Troy), Inc. identified that the 
Meggitt Inspection Procedure, Document No. IP-347, dated May 17, 2014, 
allows repair of combustion tubes that do not pass the pressure decay 
test (PDT); however, the proposed AD required a combustion tube 
replacement. We infer that the commenter wants to allow the repair of 
the combustion tube when it fails the PDT.
    We disagree with allowing repair of the combustion tube when it 
fails the PDT. The cracked combustion tube metal wall becomes oxidized 
and the cross-section of the crack is contaminated by combusted fuel 
residuals; therefore, there is no way to make a reliable repair. The 
welding will crack again in an unpredictable period of service time.
    We did not make any changes to this SNPRM as a result to this 
comment.

Request To Delay Issuance of AD Until PDT Procedure Is Publically 
Available

    Anthony Saxton requested we delay the issuance of the final rule 
until the PDT procedure is publicly available. He stated that he had a 
difficult time getting a copy of the procedure.
    We do not agree with the commenter about delaying the rule. By 
policy, the FAA cannot post to the public docket service information 
that is part of the proposed action until the publication of the final 
rule unless there is written permission from the design approval 
holder. The FAA does not currently have such written permission. We 
encourage the commenter to obtain a copy of this document from the 
design approval holder. After the final rule is published in the 
Federal Register, the PDT procedure will be readily available to the 
public in the docket.
    We did not make changes to this SNPRM based on this comment.

Request To Change Number of Airplanes Affected and Number of Labor 
Hours Required To Comply

    Anthony Saxton commented that the number of airplanes affected was 
too low and the labor cost was too low.
    We partially agree with the commenter. We agree the number of 
airplanes affected was not complete, but was the FAA's best estimate at 
the time. We obtained our initial information from the FAA aircraft 
registry, and the registry does not identify which airplanes have 
combustion heaters. An FAA economist has completed a more complete 
assessment of the number of affected aircraft during the development of 
the initial regulatory flexibility analysis. The estimated number of 
affected airplanes has been modified based on the initial regulatory 
flexability analysis.
    We disagree with modifying the labor hours to perform the labor 
without more substantive information to support a different number.

Request To Withdraw the NPRM

    William West commented that AD action is not needed. He requested 
we withdraw the NPRM and provide guidance to owners/operators reminding 
them that if the heater malfunctions to not use it until it has been 
properly inspected.
    We disagree with this comment. We completed a review of the 
accident/incident data as well as service difficulty reports over 
several years. The level of risk identified in the data review shows 
that we should address this unsafe condition through mandatory action 
rather than guidance. This proposed AD action is consistent with AD 
actions taken against other similar products. We have no way of 
assuring that the unsafe condition has been mitigated through voluntary 
guidance action.
    We did not make changes to this SNPRM based on this comment.

Request To Allow Limited Decay in the PDT

    Harold Haskins commented that we should do a PDT that allows some 
leakage as per AD 2004-21-05 (69 FR 61993, October 22, 2004). He 
commented that the test identified in the Meggitt (Troy), Inc. 
procedure is not really a pressure decay test because no decay is 
allowed. Allowing a certain amount of decay/leakage is consistent with 
other AD actions.
    We agree with the commenter that there are other ADs where the 
required pressure decay tests allow a certain amount of leakage; 
however, we disagree with modifying the SNPRM because Meggitt (Troy), 
Inc., as the design approval holder, has the responsibility to develop 
what they believe is appropriate procedures to maintain their 
combustion heaters. Owners/operators may provide substantiating data 
and request approval of an alternative method of compliance (AMOC) 
using the procedures found in 14 CFR 39.19 and specified in paragraph 
(m) of this SNPRM.
    We did not make changes to this SNPRM based on this comment.

Request To Change the Listing of the Part Numbers or Model Numbers 
Affected

    Sin Kwong Chew, Anthony Saxton, and the National Transportation 
Safety Board (NTSB) commented that we should use the part numbers or 
more detailed model numbers for the affected heaters. Another commenter 
suggested we use the four upper level model series number.
    We agree with changing how the model and series numbers are listed 
in the Applicability, paragraph (c) of this proposed AD. We want to 
ensure that the applicability of the proposed AD will address all 
affected model/part number heaters.
    We modified the Applicability, paragraph (c) of this proposed AD, 
to state the upper level model number of the heaters and to specify 
that all the part number heaters and dash numbers are included under 
that higher level designation.

Request Change to Procedures

    William Sandmann requested we change the heater disconnect 
procedures to cap off the fuel supply as near to the fuel source as 
possible to reduce the possibility that fuel may leak from the fuel 
line.
    We disagree with this comment. The manufacturer's instructions are 
FAA approved and acceptable. The commenter's suggestion may be an 
improvement on the manufacturer's instructions, but it is not required 
and is too detailed a level to include in this proposed AD.
    We did not make changes to this SNPRM as a result of this comment.

Request Change to Credit for Previous Inspections

    Chris (no last name or company affiliation given) requested we 
allow

[[Page 76534]]

credit for PDTs previously done using the manufacturer's instructions 
within the last 2 years/250 hours. The commenter also requested that we 
do not allow credit for the general inspection of the combustion heater 
because previous instructions are not sufficient to meet the new 
inspection criteria.
    We agree with the commenter's suggestions. The proposed AD contains 
the language ``unless already done'' in paragraph (f) Compliance. That 
language allows credit for any of the actions required by the AD that 
were performed before the effective date of the AD using the 
instructions required by the AD. That language does not allow credit 
for the previous instructions in AD 81-09-09 since we agree that they 
are not sufficient to meet the inspection criteria.
    We did not make changes to the SNPRM based on this comment.

Request Replacement of Combustion Heater Instead of Overhaul

    Anthony Saxton and the Aircraft Owners and Pilot's Association 
(AOPA) requested we require replacement of the combustion heater tube 
instead of an overhaul of the combustion heater if a combustion heater 
fails the PDT. An overhaul is a costly requirement that adds no 
additional safety benefit.
    We agree with the commenters' suggestion. Additional inspections in 
the proposed AD would require inspection and possible replacement of 
individual components of the combustion heater. Therefore, if the 
heater fails the PDT, replacement of the combustion heater tube would 
be a better option rather than heater overhaul.
    We have modified the corrective action language for a PDT failure 
to replacement, disable, or remove the combustion heater.

Request Removal of Combustion Heater Model 8248

    Harold Haskins and William Sandmann commented they were unaware of 
a Model 8248 combustion heater.
    We agree with this comment. The Model 8248 was included based on 
the FAA technical standard order (TSO) database. After further 
research, Meggitt (Troy), Inc. verified that the Model 8248 was 
included in the database in error and did not exist.
    We have removed the Model 8248 combustion heater from the 
Applicability, paragraph (c) of this proposed AD.

Request the Addition of Service Information

    Harold Haskins requested we add the service information for the 
Model 8240 and 8259 combustion heaters.
    We agree with the commenter's suggestion.
    We have added South Wind Service Manual for Stewart Warner South 
Wind Aircraft Heaters 8240-A, 8240-C, 8259-A, 8259-C, 8259-DL, 8259-
FL1, 8259-GL1, 8259-GL2, Form No. 09-998 (Rev. 12-69) to the service 
information required for this proposed AD.

Request To Delete Piper From Possible Combustion Heater Installation

    Harold Haskins requested that we delete Piper Aircraft, Inc. 
(Piper) airplanes from possible airplanes that may have the affected 
combustion heaters installed. He does not know of any Piper airplanes 
that have the affected heaters installed.
    We disagree with this comment. The proposed AD addressed the 
combustion heaters at the component level, and they have the potential 
for installation on various airplanes. Also, this AD as proposed in 
this SNPRM would expand the applicability to include combustion heaters 
that are installed on Piper airplanes as well as any other airplanes 
not listed, thus the reason for the phrase ``are installed on, but not 
limited to'' in the applicability.

Request Increasing the Time Allowed for Initial Compliance Time

    Anthony Saxton and AOPA requested modifying the initial compliance 
time to provide a longer period of time to comply. Two commenters 
suggested modifing the compliance time to better coincide with a normal 
maintenance schedule--within the next 10 hours of time-in-service of 
the combustion heater or at the next scheduled 100-hour inspection, 
annual inspection, or phase inspection. This would allow maintenance 
shops to better accommodate owners/operators in complying with the AD.
    We agree with the commenters. Since the NPRM, this SNPRM adds 
combustion heater models to the Applicability, paragraph (c) of this 
proposed AD. It would be appropriate to allow more time to assure that 
maintenance facilities are able to support doing the work required by 
the AD.
    We have modified the wording for the initial inspection compliance 
times for the combustion heater inspection, combustion heater 
installation inspection, and the PDT to better coincide with regularly 
scheduled maintenance.

Request Adding Document Number to Service Information

    James W. Tartar Jr. and Meggitt (Troy), Inc. requested adding the 
document number for the Meggitt (Troy), Inc. inspection procedure for 
the PDT for clarity.
    We agree with this comment. In this proposed AD, we cite the 
Meggitt (Troy), Inc. inspection procedure for the PDT as Meggitt 
Inspection Procedure, Document No. IP-347, dated May 17, 2014.

Request the AD Include an Analysis of the Impact on Small Businesses

    Anthony Saxton requested that we include in the AD an analysis of 
the AD's impact on small businesses. The commenter stated they are 
aware of a number of small businesses that operate the affected 
airplanes.
    We agree with this comment. The commenter has a good understanding 
of the usage of the airplanes affected by this SNPRM. Also, this 
proposed AD adds combustion heater models to the Applicability, 
paragraph (c) of this proposed, that will affect additional airplanes 
over that affected in the proposed rule.
    We have completed an initial regulatory flexability analysis that 
we have included in its entirety in this SNPRM.

Support of Proposed AD

    AOPA, NTSB, William Sandmann, and Anthony Saxton all supported the 
general intent of the proposed AD action.

Related Service Information Under 1 CFR Part 51

    We reviewed the following service information that applies to this 
proposed AD:

--Stewart-Warner South Wind Corporation South Wind Service Manual for 
Stewart Warner South Wind Aircraft Heaters 8240-A, 8240-C, 8259-A, 
8259-C, 8259-DL, 8259-FL1, 8259-GL1, 8259-GL2, Form No. 09-998, 
revised: December 1969;
--South Wind Division Stewart-Warner Corporation Service Manual Beech 
Aircraft Corporation PM-20688, Part No. 404-001039 Heater Assy. (SW 
8253-B), revised: April 1965;
--South Wind Division Stewart-Warner Corporation Service Manual South 
Wind Aircraft Heater 8472 Series, Form No. 09-1015, issued: April 1975; 
and

    The service information above describes procedures for inspection 
of the combustion heater and inspection of the installation of the 
combustion heater for the applicable heater models.

[[Page 76535]]

    We also reviewed Meggitt Inspection Procedure, Pressure Decay Test, 
Aircraft Heaters, dated May 17, 2014. This service information 
describes procedures for the PDT for airplane combustion heaters for 
all heater models.
    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 the ADDRESSES section.

FAA's Determination

    We are proposing this SNPRM 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. 
Certain changes described above expand the scope of this rulemaking. As 
a result, we have determined that it is necessary to reopen the comment 
period to provide additional opportunity for the public to comment on 
this SNPRM.

Proposed Requirements of This SNPRM

    This SNPRM would require repetitive inspections of the combustion 
heater and repetitive general inspections of the combustion heater 
installation, replacing any parts or components as necessary. This 
SNPRM would also require repetitive PDTs, with replacement of the 
combustion heater tube, disabling, or removal of the combustion heater 
in the event of PDT failure. This SNPRM also modifies the inspection 
and PDT compliance times allowing for the inspections to coincide with 
regularly scheduled maintenance. This SNPRM would not allow repair of 
the combustion heater tube.
    For combustion heater models other than Models 8240, 8253, 8259, 
and 8472, this SNPRM does not have referenced service information 
associated with certain required inspections and the PDT and, if 
necessary, any replacement(s) that may be required. Appendix 1 of this 
SNPRM contains a listing of service information that provides specific 
instructions, for certain inspections and replacements, that may be 
used to apply for an AMOC. However, the listing in appendix 1 to this 
SNPRM does not include any instructions for the required PDT because 
these procedures do not exist. If you are unable to obtain instructions 
for the PDT, you must disable or remove the combustion heater.
    The service information listed in appendix 1 of this SNPRM did not 
meet Office of the Federal Register regulatory requirements for 
incorporation by reference approval due to the condition of the 
documents.
    We are evaluating the actions required in AD 69-13-03 (38 FR 33765, 
December 7, 1973) and may take further AD action in the future.

Differences Between This SNPRM and the Service Information

    The proposed AD would prohibit repair of any defective combustion 
tube while the service information does not specify this.

Costs of Compliance

    We estimate that this proposed AD affects 6,300 combustion heaters 
installed on, but not limited to, certain Beech, Britten-Norman, Cessna 
Aircraft Company, and Piper Aircraft, Inc. airplanes of U.S. registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
              Action                      Labor cost             Parts cost           product        operators
----------------------------------------------------------------------------------------------------------------
Inspections and pressure decay      7 work-hours x $85     Not applicable.......            $595      $3,748,500
 test of the combustion heater.      per hour = $595.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary combustion 
heater disable/removal/related replacement that would be required based 
on the results of the proposed inspections/test. We have no way of 
determining the number of aircraft that might need a combustion heater 
disable/removal/related replacement:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                Action                            Labor cost                   Parts cost             product
----------------------------------------------------------------------------------------------------------------
Replace combustion heater tube........  8 work-hours x $85 per hour =   $3,900..................          $4,580
                                         $680.
Replace temperature switches..........  1 work-hour x $85 per hour =    $320....................             405
                                         $85.
Repair pump...........................  2 work-hours x $85 per hour =   $470....................             640
                                         $170.
Disable heater........................  2 work-hours x $85 per hour =   Not Applicable..........             170
                                         $170.
Remove heater.........................  3 work-hours x $85 per hour =   Not Applicable..........             255
                                         $255.
----------------------------------------------------------------------------------------------------------------

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.

Initial Regulatory Flexibility Analysis

    This section presents the initial regulatory flexibility analysis 
(IRFA) that was done for this action. We have reworded and reformatted 
for Federal Register publication purposes. The IRFA in its original 
form can be found in the docket at http://www.regulations.gov.

[[Page 76536]]

Introduction and Purpose of This Analysis

    The Regulatory Flexibility Act of 1980 (Pub. L. 96-354) (RFA) 
establishes ``as a principle of regulatory issuance that agencies shall 
endeavor, consistent with the objectives of the rule and of applicable 
statutes, to fit regulatory and informational requirements to the scale 
of the businesses, organizations, and governmental jurisdictions 
subject to regulation.'' To achieve this principle, the RFA requires 
agencies to solicit and consider flexible regulatory proposals and to 
explain the rationale for their actions to assure that such proposals 
are seriously considered.'' 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 rule will 
have a significant economic impact on a substantial number of small 
entities. If the agency determines that it will, the agency must 
prepare an initial regulatory flexibility analysis (IRFA) as described 
in the RFA. The FAA finds that the proposed AD would have a significant 
economic impact on a substantial number of small entities. Accordingly, 
in the following sections we discuss the compliance requirements of the 
proposed AD, the cost of compliance, and the economic impact on small 
entities.
    Section 603(a) of the RFA requires that each initial regulatory 
flexibility analysis contain:
--A description of the reasons action by the agency is being 
considered;
--A succinct statement of the objectives of, and legal basis for, the 
proposed rule;
--A description of and, where feasible, an estimate of the number of 
small entities to which the proposed rule will apply;
--A description of the projected reporting, recordkeeping and other 
compliance requirements of the proposed rule, including an estimate of 
the classes of small entities which will be subject to the requirement 
and the type of professional skills necessary for preparation of the 
report or record; and to the extent practicable, an identification of 
all relevant Federal rules which may duplicate, overlap or conflict 
with the proposed rule; and
--A description of any significant alternatives to the proposed rule 
which accomplish the stated objectives of applicable statues and which 
minimize any significant economic impact of the proposed rule on small 
entities.

1. Objectives of, and Legal Basis for, the Proposed Rule

    Title 49 of the U.S. 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 FAA'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 the airplanes identified in this 
proposed AD.

2. A Description of the Reasons Action by the Agency Is Being 
Considered

    This proposed AD stems from the crash of a Cessna 401 near Chanute, 
Kansas, on May 11, 2012, killing the pilot and three of the four 
passengers aboard, and seriously injuring the fourth passenger. 
According to the NTSB report, the crash occurred after dark smoke 
emanated from the cabin heater and entered the cabin obscuring the 
occupants' vision. According to the Report: ``The smoke likely 
interfered with the pilot's ability to identify a safe landing site.'' 
When the pilot attempted an emergency landing in a field, the 
airplane's wing contacted the ground and the airplane cartwheeled.
    The NTSB determined the probable cause of the accident to be:

The malfunction of the cabin heater, which resulted in an inflight 
fire and smoke in the airplane. Contributing to the accident was the 
pilot's lack of understanding concerning the status of the 
airplane's heater system following an earlier overheat event and the 
risk of its continued use. Also contributing were the inadequate 
inspection criteria for the cabin heater.

    As result of this accident, the FAA is proposing this AD to detect 
and correct a hazardous condition caused by deterioration of the 
combustion heater, a condition that could lead to ignition of heater 
components and result in smoke and fumes in the airplane cabin.

3. A Description of and an Estimate of the Number of Small Entities To 
Which the Proposed Rule Will Apply

    This proposed AD would supersede AD 81-09-09, which applies to 8000 
series Meggitt combustion heaters installed on certain twin-engine 
piston airplanes, primarily Cessna 300 and 400 series airplanes, but 
also installed on the Beech D18S twin-engine airplane and some Britten 
Norman twin-engine piston airplanes. The proposed AD would extend 
applicability to 900 series Meggitt combustion heaters installed on 
certain Cessna single-engine piston airplanes, Cessna 310 twin-engine 
airplanes, Lake LA-4 and LA-250 airplanes, certain Ryan Navion single-
engine piston airplanes and certain Piper PA-23 and PA-30 airplanes. 
The FAA estimates that there are 4,121 airplanes equipped with 8000 
series Meggitt combustion heaters, and 2,123 airplanes equipped with 
900 series Meggitt combustion heaters. Since many of these airplanes 
are registered to Limited Liability Companies (LLCs), Limited Liability 
Partnerships (LLPs) and other company forms typically suited for single 
proprietors, small partnerships, etc., we conclude that the proposed 
rule would affect a substantial number of small entities.

4. Duplicative, Overlapping or Conflicting Federal Rules

    The FAA is unaware of any Federal rules that duplicate, overlap, or 
conflict with this proposed AD.

5. Significant Alternatives to the Proposed Rule

    Because of an unsafe condition that is likely to exist or develop 
on the airplanes identified in this proposed AD, there is no feasible 
significant alternative to requiring the actions of this proposed AD. 
The FAA invites public comment on this determination.
    The FAA considered allowing more flight hours or calendar time 
before requiring compliance, but this alternative would increase the 
risk of another fatal accident. This proposed AD allows the combustion 
heater to be disconnected or removed, but, as noted above, operating 
without a heater is unlikely to be viable.

6. Reporting, Recordkeeping, and Other Compliance Requirements of the 
Proposed Rule

    Small entities would incur no new reporting and recordkeeping 
requirements as a result of this rule.

Compliance Requirements

    This proposed AD would carry over the following requirements from 
AD 81-09-09:

--Conduction of the 250-hour heater inspection every 250 hours of 
heater operation, in accordance with the manufacturer's service manual. 
We estimate the labor cost of this action to be 2 hours x $85 = $170.

[[Page 76537]]

--General inspection of the heater installation at the same time as the 
250-hour inspection. We estimate the labor cost of this action to also 
be 2 hours x $85 = $170.

    Since the proposed rule would extend applicability to 900 series 
heaters Meggitt combustion heaters, which are installed on certain 
airplanes, there is an incremental cost associated with the existing 
requirement for these two inspections. There is no incremental cost 
associated with applicability to 8000 series heaters, installed on 
certain airplanes, as the current rule already applies to these 
heaters.
    This proposed AD would add the following new provisions, which will 
apply to both 900 and 8000 series heaters installed on certain 
airplanes:

--During each 250-hour inspection more detailed actions would be 
required, namely inspection of the thermostat and upper limit switches, 
and inspection of the solenoid valve and fuel pump. In conjunction with 
the 250-hour and installation inspections already required, the labor 
cost of these more detailed actions would be one hour of labor at $85. 
``On-condition'' costs to replace the temperature switches would be an 
additional hour of labor ($85) and $320 in materials cost, for a total 
of $405. On-condition costs to repair/overhaul the pump would be an 
additional two hours of labor ($170) and $470 in materials cost for a 
total of $640.
--Operators would be required to replace defective combustion tubes 
with new tubes as repair of combustion tubes would be prohibited. We 
estimate the cost of prohibiting repair of combustion tubes to be 
minimal as industry reports that the Meggitt heater combustion tubes 
are effectively non-repairable.
--At the same time as the 250-hour and installation inspection, a 
combustion heater pressure decay test (PDT) would be required. The PDT 
would cost $170. If the combustion heater fails the PDT, the operator 
would be required to replace the combustion tube at an installed cost 
of $4,580.
--Operators have the options of disabling the heater at an estimated 
cost of $170 or removing it at estimated cost of $255.

Cost of Compliance

    In calculating the cost of compliance, we assume that operating 
without a heater is unlikely to be viable. We estimate the ten-year 
cost of the proposed rule. Based on data in the 2014 GA Survey, we can 
somewhat conservatively assume that average flight hours per airplane 
per year are about 100 hours. We estimate heater time to be 50 percent 
of airplane flight hours so, on average, flight hours will accumulate 
to about 1,000 hours in ten years and heater time will accumulate to 
about 500 hours. Since requirements for inspection internals are ``250 
hours of combustion heater operations or two years, whichever occurs 
first,'' we expect inspections to usually occur every two years. As 
will be seen below, compliance costs are dominated by the almost 
immediate requirement for the PDT test.

Pressure Decay Test

    The FAA estimates that 90 percent of combustion tubes tested will 
fail the first PDT test. Since replacing the combustion tube, like an 
overhaul, requires complete disassembly of the combustion heater, we 
somewhat conservatively assume that operators will overhaul their 
combustion heaters at $4,580, rather than simply replace the combustion 
tube, at $4,900. Major components such as the combustion tube, fuel 
pump, and temperature switches that are typically replaced or 
overhauled in a combustion heater overhaul have service lives of 750 
heater hours, equivalent to about 1,500 flight hours or 15 years. 
Therefore, we assume that once replaced or overhauled, these components 
will not need to be replaced during our 10-year period of cost 
estimation. So aside from the initial tube replacement, we estimate 
that, for inspections required by this proposed AD, ``on-condition'' 
costs would be minimal.
    Table 1 below shows our calculation of compliance cost for 
airplanes with the affected Meggitt combustion heaters. We assume the 
rule to be effective in 2017 and, as discussed above, in the first year 
we assume the combustion heater fails the PDT resulting in a subsequent 
overhaul. For the 8000 series heaters note that the $935 labor cost for 
2017 includes three hours of labor ($255) for the detailed inspection 
and the PDT in addition to eight hours of labor for the overhaul 
($680).
    As the table shows, we estimate the present value cost of 
compliance to be $6,020 for airplanes equipped with 8000 series Meggitt 
combustion heaters and $7,514 for airplanes equipped with 900 series 
Meggitt combustion heaters. The lower cost for airplanes with 8000 
series combustion heaters reflects the previously noted fact that 8000 
series heaters are currently subject to the 250-hour inspection and 
installation inspection requirements, and, therefore, the incremental 
cost would be correspondingly less for airplanes with 8000 series 
combustion heaters compared to airplanes with 900 series heaters.

Economic Impact on Small Entities

    If the cost of compliance is greater than 2 percent of the value of 
an operator's airplane, the FAA considers the cost impact to be 
significant. So if the value of an airplane equipped with an affected 
Meggitt combustion heater is less than 50 times the cost of compliance, 
we consider that the operator of the airplane would incur a substantial 
economic impact. With a present value cost of about $6,000 for 
airplanes equipped with 8000 series Meggitt combustion heaters, the FAA 
considers the cost impact to be significant for all such airplanes with 
values below about $300,000. With a present value cost of about $7,500 
for airplanes equipped with 900 series Meggitt combustion heaters, the 
FAA considers the cost impact to be significant for all such airplanes 
with values below about $350,000. The airplanes equipped with the 
affected heaters are single- and twin-engine piston airplanes that, for 
the most part, were manufactured from the 1940s to the 1980s, and range 
in price from about $350,000 for a Cessna 221C Golden Eagle down to a 
price as low as $30,000 for a Piper 23-150 Apache. Accordingly, most of 
the 6,244 airplanes equipped with Meggitt combustion heaters have 
values low enough to consider that the airplane operators would incur a 
significant economic impact. As noted above, many of these airplanes 
are registered to LLCs and other small companies.
    The FAA therefore concludes that this proposed AD would have a 
significant economic impact on a substantial number of small entities.

[[Page 76538]]

                                                              Table 1--Costs of Compliance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Mtls + labor                                      Discount
                  Year                    Materials cost    Labor cost         cost                   Actions              factor  (@7%)      PV Cost
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Airplanes with 8000 Series Meggitt Combustion Heaters
--------------------------------------------------------------------------------------------------------------------------------------------------------
2017....................................          $4,220            $935          $5,155  Detailed inspection (1 hr                1.000          $5,155
                                                                                           labor), PDT (2 hrs labor)--
                                                                                           Overhaul after assumed
                                                                                           failure (8 hrs labor, $4,220
                                                                                           materials).
2019....................................  ..............             255             255  Detailed inspection (1 hr                0.873             223
                                                                                           labor), PDT inspection (2 hrs
                                                                                           labor).
2021....................................  ..............             255             255  Detailed inspection (1 hr                0.763             195
                                                                                           labor), PDT inspection (2 hrs
                                                                                           labor).
2023....................................  ..............             255             255  Detailed inspection (1 hr                0.666             170
                                                                                           labor), PDT inspection (2 hrs
                                                                                           labor).
2025....................................  ..............             255             255  Detailed inspection (1 hr                0.582             148
                                                                                           labor), PDT inspection (2 hrs
                                                                                           labor).
2027....................................  ..............             255             255  Detailed inspection (1 hr                0.508             130
                                                                                           labor), PDT inspection (2 hrs
                                                                                           labor).
                                         ------------------------------------------------                                -------------------------------
    Total PV Cost.......................  ..............  ..............  ..............  ..............................  ..............           6,020
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Airplanes with 900 Series Combustion Meggitt Heaters
--------------------------------------------------------------------------------------------------------------------------------------------------------
2017....................................           4,220           1,275           5,495  250-hr inspection (2 hrs                 1.000           5,495
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor)--
                                                                                           Overhaul after assumed
                                                                                           failure (8 hrs labor, 4,220
                                                                                           materials).
2019....................................  ..............             595             595  250-hr inspection (2 hrs                 0.873             520
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor).
2021....................................  ..............             595             595  250-hr inspection (2 hrs                 0.763             454
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor).
2023....................................  ..............             595             595  250-hr inspection (2 hrs                 0.666             396
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor).
2025....................................  ..............             595             595  250-hr inspection (2 hrs                 0.582             346
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor).
2027....................................  ..............             595             595  250-hr inspection (2 hrs                 0.508             302
                                                                                           labor), installation
                                                                                           inspection (2 hrs labor),
                                                                                           detailed inspection (1 hr
                                                                                           labor), PDT (2 hrs labor).
                                         ------------------------------------------------                                -------------------------------
    Total PV Cost.......................  ..............  ..............  ..............  ..............................  ..............           7,514
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 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 removing AD 81-09-09, Amendment 39-
4102 (46 FR 24936, May 4, 1981) and adding the following new 
airworthiness directive (AD):

[[Page 76539]]

Meggitt (Troy), Inc.: Docket No. FAA-2014-0603; Directorate 
Identifier 2013-CE-026-AD.

(a) Comments Due Date

    We must receive comments by December 19, 2016.

(b) Affected ADs

    This AD replaces AD 81-09-09, Amendment 39-4102 (46 FR 24936, 
May 4, 1981).

(c) Applicability

    (1) This AD applies to Meggitt (Troy), Inc. (previously known as 
Stewart Warner South Wind Corporation and as Stewart Warner South 
Wind Division) Models (to include all dash number and model number 
variants) 921, 930, 937, 940, 944, 945, 977, 978, 979, 8240, 8253, 
8259, and 8472 combustion heaters that:
    (i) Are installed on, but not limited to, certain Beech, 
Britten-Norman, Cessna Aircraft Company, and Piper Aircraft, Inc. 
airplanes; and
    (ii) certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 2140; Heating System.

(e) Unsafe Condition

    This AD was prompted by an airplane accident and reports we 
received that the combustion heater was malfunctioning. We are 
issuing this AD to detect and correct a hazardous condition caused 
by deterioration of the combustion heater, which could lead to 
ignition of components and result in smoke and fumes in the cabin.

(f) Compliance

    Comply with this AD by doing one of the actions in paragraphs 
(f)(1), (2), or (3) of this AD at the compliance times indicated, 
unless already done. If the hours of combustion heater operation 
cannot be determined, use 50 percent of the airplane's hours time-
in-service (TIS):
    (1) Perform the actions specified in paragraphs (g) through (j) 
of this AD;
    (2) Disable the heater following the instructions in paragraph 
(k)(1) of this AD; or
    (3) Remove the heater following the instructions in paragraph 
(k)(2) of this AD.

(g) Inspections and Pressure Decay Test (PDT) of the Combustion Heater

    Within the next 10 hours TIS of the combustion heater after the 
effective date of this AD or the next scheduled 100-hour inspection, 
annual inspection, or phase inspection that occurs 30 days after the 
effective date of this AD, whichever occurs first, and repetitively 
thereafter at intervals not to exceed 250 hours of combustion heater 
operation or two years, whichever occurs first, do the following 
inspections and PDT listed in paragraphs (g)(1) through (4) of this 
AD. You may do one of the actions in paragraph (k)(1) or (2) of this 
AD in lieu of doing the inspections required by paragraph (g).
    (1) Inspections using the instructions in paragraph (i)(1) or 
(j) of this AD, as applicable.
    (2) Inspections using the steps listed in paragraphs (g)(2)(i) 
through (v) of this AD:
    (i) Inspect the thermostat switch (external from heater) and 
upper limit switch (located on the heater). In cold static 
condition, both switches should be in closed position; in operation 
(hot) condition, both switches should regulate their sensed 
temperatures within +/-10 degrees F.
    (ii) Inspect the solenoid valve and fuel pump for fuel leak, 
corrosion, diaphragm crack, metal shavings, and excess grease.
    (iii) With the heater operating, inspect the fuel pump output 
pressure for proper gauge hook up and pressure range readings.
    (iv) Inspect the combustion heater's fuel pump operating 
pressure to assure it is not affected by other on-board pumps.
    (v) Inspect the heater to assure it instantly responds to the 
on/off switch.
    (3) Installation inspections and checks using the steps listed 
in paragraphs (g)(3)(i) through (iv) of this AD:
    (i) Inspect ventilating air and combustion air inlets and 
exhaust outlet correcting any restrictions and ensure attachment 
security.
    (ii) Inspect drain line and ensure it is free of obstruction.
    (iii) Check all fuel lines for security at joints and shrouds, 
correcting/replacing those showing evidence of looseness or leakage.
    (iv) Check all electrical wiring for security at attachment 
points, correcting conditions leading to arcing, chafing or 
looseness.
    (4) Pressure decay test using the instructions in paragraph 
(i)(2) or (j) of this AD, as applicable.

(h) Replacement of the Heater Tube and/or Correct or Replace Other 
Assemblies

    If any discrepancies are found during any of the inspections/
tests required in paragraphs (g)(1), (2), (3), and/or (4) of this 
AD, before further flight, replace the defective heater tube and/or 
correct or replace other defective assemblies as necessary. You must 
use the instructions in paragraph (i) or (j) of this AD, as 
applicable, to do any necessary replacements. This AD does not allow 
repair of the combustion tube. You may do one of the actions in 
paragraph (k)(1) or (2) of this AD in lieu of doing the replacements 
required by paragraph (h).

(i) Procedures for Inspection, PDT, and Replacement for Models 8240, 
8253, 8259, and 8472

    (1) For the inspections required in paragraph (g)(1) of this AD 
and the replacement(s) that may be required in paragraph (h) of this 
AD, use the service information listed in paragraphs (i)(1)(i) 
through (iii) of this AD, as applicable, or do one of the actions in 
paragraph (k)(1) or (2) of this AD.
    (i) Stewart-Warner South Wind Corporation South Wind Service 
Manual for Stewart Warner South Wind Aircraft Heaters 8240-A, 8240-
C, 8259-A, 8259-C, 8259-DL, 8259-FL1, 8259-GL1, 8259-GL2, Form No. 
09-998, revised: December 1969;
    (ii) South Wind Division Stewart-Warner Corporation Beech 
Aircraft Corporation Service Manual PM-20688, Part No. 404-001039 
Heater Assy. (SW 8253-B), revised: April 1965; or
    (iii) South Wind Division Stewart-Warner Corporation Service 
Manual South Wind Aircraft Heater 8472 Series, Form No. 09-1015, 
issued: April 1975.
    (2) For the pressure decay test (PDT) required in paragraph 
(g)(4) of this AD, use Meggitt Inspection Procedure, Pressure Decay 
Test, Aircraft Heaters, IP-347, dated May 17, 2014, or do one of the 
actions in paragraph (k)(1) or (2) of this AD.

(j) Procedures for Inspection, PDT, and Replacement for Models Other 
Than Models 8240, 8253, 8259, and 8472

    This AD does not have referenced service information associated 
with the mandatory requirements of this AD for models other than 
Models 8240, 8253, 8259, and 8472. For the required inspections and 
PDT specified in paragraphs (g)(1) and (4) of this AD and, if 
necessary, any replacement(s) specified in paragraph (h) of this AD, 
you must contact the manufacturer to obtain FAA-approved inspection, 
replacement, and PDT procedures approved specifically for this AD 
and implement those procedures through an alternative method of 
compliance (AMOC) or do one of the actions in paragraph (k)(1) or 
(2) of this AD. You may use the contact information found in 
paragraph (n)(2) to contact the manufacturer. Appendix 1 of this AD 
contains a listing of service information that provides specific 
instructions, for certain inspections and replacements, that you may 
use to apply for an AMOC following paragraph (m) of this AD. The 
service information listed in appendix 1 of this AD did not meet 
Office of the Federal Register regulatory requirements for 
incorporation by reference approval due to the condition of the 
documents. However, the listing in appendix 1 to this AD does not 
include any instructions for the PDT required in paragraph (g)(4) 
because these procedures do not exist.

(k) Disable or Removal of the Combustion Heater

    As an option to the inspection and replacement actions specified 
in paragraphs (g) and (h) of this AD, within the next 10 hours TIS 
of the combustion heater after the effective date of this AD or the 
next scheduled 100-hour inspection, annual inspection, or phase 
inspection that occurs 30 days after the effective date of this AD, 
whichever occurs first, do one of the following actions:
    (1) Disable the heater by the following actions:
    (i) Disconnect and cap the heater fuel supply;
    (ii) Disconnect circuit breakers;
    (iii) Tag the main switch ``Heater Inoperable''; and
    (iv) The ventilation blower can stay functional.
    (v) If you re-enable the combustion heater, you must perform one 
of the actions in paragraphs (f)(1) through (3) of this AD.
    (2) Remove the heater by the following actions:
    (i) Disconnect and cap the heater fuel supply;
    (ii) Disconnect/remove circuit breakers;
    (iii) Remove exhaust pipe extension;

[[Page 76540]]

    (iv) Cap the exhaust opening;
    (v) Remove the heater; and
    (vi) Do weight and balance for the aircraft.
    (vii) If you install an applicable combustion heater, you must 
perform one of the actions in paragraphs (f)(1) through (3) of this 
AD.

(l) Special Flight Permit

    Special flight permits are permitted in accordance with 14 CFR 
39.23 with the following limitation: Use of the heater is not 
allowed.

(m) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Chicago 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 paragraph (o)(1) of this AD.
    (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.
    (3) AMOCs approved for AD 81-09-09 (46 FR 24936, May 4, 1981) 
are not approved as AMOCs for this AD.

(n) Related Information

    (1) For more information about this AD, contact Chung-Der Young, 
Aerospace Engineer, Chicago Aircraft Certification Office, FAA, 
Small Airplane Directorate, 2300 East Devon Avenue, Des Plaines, IL 
60018-4696; telephone (847) 294-7309; fax (847) 294-7834 email: 
chung-der.young@faa.gov.
    (2) For service information identified in this AD, contact 
Meggitt Control Systems, 3 Industrial Drive, Troy, Indiana 47588; 
telephone: (812) 547-7071; fax: (812) 547-2488; email: 
infotroy@meggitt.com; Internet: www.stewart-warner.com. You may view 
this referenced service information at the FAA, Small Airplane 
Directorate, 901 Locust, Kansas City, Missouri 64106. For 
information on the availability of this material at the FAA, call 
(816) 329-4148.

Appendix 1 to Docket No. FAA-2016-0603

    The following service information applies to certain combustion 
heater models affected by this AD, but the service information can 
not be required by the AD. You may use this service information for 
procedural guidance when applying for an alternative method of 
compliance.

--South Wind Service Manual P.M. 35710 Aircraft Heaters 8240-E, 
8259-HL1, HL2, -L, supplements attached HR2.JR2.M;
--South Wind Service Manual PM35710 Aircraft Heaters
--Stewart-Warner Corporation South Wind Division Service Manual 
South Wind Aircraft Heaters Series 921 and 930, Ind-506, Revision 4-
53;
--Stewart-Warner Corporation South Wind Division Service Manual 
SouthWind Series 940 Heater, PM-10035, Revision 3-82;
--Stewart-Warner Corporation South Wind Division Service Manual 
South Wind Model 978 Personal Heater, Form No. PM6348 (12-56);
--South Wind Service Manual Model 979-B1 Aircraft Heater, South Wind 
Division of Stewart-Warner Corporation, (3-51);
--Navion Model 977-B Installation Manual Section I, Section II, 
Section III, and Section IV.

    Issued in Kansas City, Missouri, on October 27, 2016.
Pat Mullen,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-26428 Filed 11-2-16; 8:45 am]
 BILLING CODE 4910-13-P