Document ID: FAA-2017-0324-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Aerospace Welding Minneapolis, Inc. Mufflers
Posted Date: 2017-04-18T04:00Z

[Federal Register Volume 82, Number 73 (Tuesday, April 18, 2017)]
[Proposed Rules]
[Pages 18265-18267]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-07775]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0324; Directorate Identifier 2017-CE-004-AD]
RIN 2120-AA64

Airworthiness Directives; Aerospace Welding Minneapolis, Inc. 
Mufflers

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 Aerospace Welding Minneapolis, Inc. mufflers, part numbers 
A1754001-23 and A1754001-25, installed on Textron Aviation Inc. (type 
certificate previously held by Cessna Aircraft Company) Models 172, 
172R, 172S, and 177 airplanes. This proposed AD was prompted by 
occurrences of cracks or broken welds in the connecting weld of the 
muffler body to muffler cuff that may allow carbon monoxide exhaust 
fumes into the cockpit heating system. This proposed AD would require 
an inspection of the muffler for leaking to identify cracks and 
replacement of the muffler. We are proposing this AD to correct the 
unsafe condition on these products.

DATES: We must receive comments on this proposed AD by June 2, 2017.

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 NPRM, contact Aerospace 
Welding Minneapolis, Inc. (AWI) 1045 Gemini Road, Eagan, Minnesota 
55121; telephone: 651-379-9888; fax: 651-379-9889; Internet: www.awi-ami.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-2017-
0324; 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: Mark Grace, Aerospace Engineer, FAA, 
Chicago Aircraft Certification Office, 2300 East Devon Avenue, Des 
Plaines, IL 60018-4696; telephone: (847) 294-7377; fax: (847) 294-7834; 
email: mark.grace@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-2017-0324; 
Directorate Identifier 2017-CE-004-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy

[[Page 18266]]

aspects of this proposed AD. We will consider all comments received by 
the closing date and may amend this proposed AD because of those 
comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We were notified of broken or cracked welds in the connecting weld 
of the muffler body to muffler cuff on certain Aerospace Welding 
Minneapolis, Inc. (AWI) mufflers, part numbers (P/Ns) A1754001-23 and 
A1754001-25 that were installed on Textron Aviation Inc. (type 
certificate previously held by Cessna Aircraft Company) Models 172, 
172R, 172S, and 177 airplanes. There have been 54 occurrences 
identified by maintenance and 2 occurrences identified by the carbon 
monoxide (CO) gas monitor warning system. This condition, if not 
corrected, could lead to CO exhaust fumes entering the cockpit heating 
system and result in inhibiting the pilot's ability to maintain control 
of the airplane.

Related Service Information Under 1 CFR Part 51

    We reviewed AWI Cessna 172 (Lycoming) Muffler Removal and 
Installation, Revision 01, January 17, 2017. The service information 
describes procedures for removing and replacing the affected mufflers. 
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.

Other Related Service Information

    We reviewed AWI Mandatory Service Bulletin No. 16063001, dated June 
30, 2015. The service bulletin describes how to identify the 
installation of an affected muffler.

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 inspecting the muffler for leaking 
to identify cracks and replacement of the muffler with an FAA-approved 
part.

Differences Between This Proposed AD and the Service Information

    The AWI service bulletin requires replacement of the muffler before 
further flight. This proposed AD would require an inspection of the 
muffler for leaking to identify cracks within 5 hours time-in-service 
(TIS) after the effective date of the AD with replacement of leaking 
mufflers before further flight. This proposed AD would allow 100 hours 
TIS or at the next annual inspection for replacement of non-leaking 
mufflers. The service bulletin also requires returning the affected 
mufflers back to AWI, and this proposed AD does not require return of 
the muffler. The actions of the proposed AD would take precedence over 
the service information.

Costs of Compliance

    We estimate that this proposed AD affects 171 mufflers installed on 
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
----------------------------------------------------------------------------------------------------------------
Inspection of muffler..........  1 work-hour x $85 per    Not applicable........             $85         $14,535
                                  hour = $85.
Replacement of the muffler.....  4 work-hours x $85 per   $350..................             690         117,990
                                  hour = $340.
----------------------------------------------------------------------------------------------------------------

    The proposed AD would affect 171 mufflers with parts manufacturer 
approval; however, only 9 mufflers remain in service.
    According to the manufacturer, some of the costs of this proposed 
AD may be covered under warranty, thereby reducing the cost impact on 
affected individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national Government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

[[Page 18267]]

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 (AD):

Aerospace Welding Minneapolis, Inc.: Docket No. FAA-20170324; 
Directorate Identifier 2017-CE-004-AD.

(a) Comments Due Date

    We must receive comments by June 2, 2017.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Aerospace Welding Minneapolis, Inc. (AWI) 
mufflers listed in figure 1 of paragraph (c) of this AD that are 
installed on but limited to the airplanes listed in figure 2 of 
paragraph (c) of this AD.

    Note 1 to paragraph (c) of this AD:  You may use AWI Mandatory 
Service Bulletin No. 16063001, dated June 30, 2015, to identify if 
an affected muffler is installed on the airplane.

         Figure 1 of Paragraph (c) of This AD--Affected Mufflers
------------------------------------------------------------------------
      Muffler part No.                    Muffler serial No.
------------------------------------------------------------------------
A1754001-23.................  33553 through 33557; 34721 through 34728;
                               35322 through 35329; 35670; 38481 through
                               38485; 38584 through 38586; and 38723
                               through 38727.
A1754001-25.................  32795 through 32800; 33558 through 33569;
                               33779 through 33790; 34636 through 34653;
                               34968 through 34984; 35159 through 35176;
                               37903 through 37906; 38174 through 38193;
                               38502 through 38506; 38566 through 38575;
                               and 38817 through 38836.
------------------------------------------------------------------------

        Figure 2 of Paragraph (c) of This AD--Affected Airplanes
------------------------------------------------------------------------
                                Textron Aviation Inc. (type certificate
      Muffler part No.            previously held by Cessna Aircraft
                                          Company) airplanes
------------------------------------------------------------------------
A1754001-23.................  Model 172 Serial numbers (S/Ns) 17259224
                               and up; Model 172R S/Ns 80001 and up; and
                               Model 172S S/Ns 8001 and up.
A1754001-25.................  Model 172 S/Ns 17256513 and up; Model 172R
                               S/Ns 80001 and up; 172S S/N 8001 and up;
                               and Model 177 S/N 1770001 and up.
------------------------------------------------------------------------

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 7820, Exhaust Noise Suppressor.

(e) Unsafe Condition

    This AD was prompted by occurrences of cracks or broken welds in 
the connecting weld of the muffler body to muffler cuff that may 
allow carbon monoxide (CO) exhaust fumes into the cockpit heating 
system. We are issuing this AD to prevent cracks in the connecting 
weld of the muffler body to muffler cuff that may allow CO fumes to 
enter the cockpit heating system and possibly inhibit the pilot's 
ability to maintain control of the airplane.

(f) Compliance

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

(g) Inspection of the Muffler

    Within 5 hours time-in-service after the effective date of this 
AD, inspect the affected muffler following the instructions listed 
in paragraphs (g)(1) through (3).
    (1) Using a vacuum cleaner with the hose attached to the blowing 
side of the vacuum (with the filter installed), attach the vacuum to 
the airplane tailpipe and seal securely.
    (2) The vacuum will pressurize the system sufficiently for a 
soap solution to be brushed or applied from a spray bottle to the 
surface of the exhaust system.
    (3) Inspect for evidence of breaches (leakage) in the system 
from cracks.
    (4) In lieu of doing this inspection and at the same within 5 
hours after the effective date of this AD compliance time, you may 
replace the affected muffler with an FAA-approved part that is not a 
muffler listed in figure 1 of paragraph (c) of this AD.
    (i) This replacement must be done following AWI Cessna 172 
(Lycoming) Muffler Removal and Installation, Revision 01, January 
17, 2017.
    (ii) If replacement is done instead of the inspection, then 
paragraph (h)(3) of this AD is the only additional requirement of 
this AD.

(h) Replacement of the Muffler

    (1) If evidence of breaches (leakage) is found during the 
inspection required in paragraph (g) of this AD, before further 
flight, replace the affected muffler with an FAA-approved part 
following AWI Cessna 172 (Lycoming) Muffler Removal and 
Installation, Revision 01, January 17, 2017.
    (2) If no evidence of breaches (leakage) is found during the 
inspection required in paragraph (g) of this AD, within the next 100 
hours TIS after the effective date of this AD or at the next annual 
inspection after the effective date of this AD, whichever occurs 
later, replace the affected muffler with an FAA-approved part that 
is not a muffler listed in figure 1 of paragraph (c) of this AD 
following AWI Cessna 172 (Lycoming) Muffler Removal and 
Installation, Revision 01, January 17, 2017.
    (3) After the effective date of this AD, do not install on any 
airplane an affected muffler listed in figure 1 of paragraph (c) of 
this AD.

 (i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Chicago Aircraft Certification Office, 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 (j)(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.

(j) Related Information

    (1) For more information about this AD, contact Mark Grace, 
Aerospace Engineer, FAA, Chicago Aircraft Certification Office, 2300 
East Devon Avenue, Des Plaines, IL 60018-4696; telephone: (847) 294-
7377; fax: (847) 294-7834; email: mark.grace@faa.gov.
    (2) For service information identified in this AD, contact 
Aerospace Welding Minneapolis, Inc. 1045 Gemini Road, Eagan, 
Minnesota 55121; telephone: 651-379-9888; fax: 651-379-9889; 
Internet: www.awi-ami.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.

    Issued in Kansas City, Missouri, on April 11, 2017.
Pat Mullen,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2017-07775 Filed 4-17-17; 8:45 am]
 BILLING CODE 4910-13-P