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PROPOSED AD BOMBARDIER, INC.: Docket No. FAA-2018-0160; Product Identifier 2017-NM-139-AD.
(a) COMMENTS DUE DATE

    We must receive comments by April 23, 2018.

(b) AFFECTED ADS

    This  AD  replaces  AD  2016-24-03,  Amendment 39-18720  (81 FR 88623,
    December 8, 2016) ("AD 2016-24-03").

(c) APPLICABILITY

    This AD applies  to  Bombardier, Inc.,  Model DHC-8-400, -401 and -402
    airplanes, certificated in any category,  serial numbers 4001 and sub-
    sequent.

(d) SUBJECT

    Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) REASON

    This AD was  prompted by reports  of cracked and  corroded barrel nuts
    found  at  the  mid-spar  location  of  the   horizontal-stabilizer-to
    -vertical-stabilizer attachment joint, and the issuance of new service
    information that includes a terminal modification. We are issuing this
    AD to detect and correct cracked and corroded barrel nuts, which could
    compromise  the  structural   integrity  of  the   vertical-stabilizer
    attachment joints and lead to loss of control of the airplane.

(f) COMPLIANCE

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

(g) RETAINED DETAILED  INSPECTION OF BARREL NUTS FOR CRACKS AND CORROSION,
    WITH NO CHANGES

    This paragraph  restates the requirements of paragraphs (g)(1) and (g)
    (2) of AD 2016-24-03, with no changes.

(1) For airplanes that have accumulated 5,400 flight hours or more or have
    been in service 32  months or more since  the date of issuance  of the
    original certificate of airworthiness or  the date of issuance of  the
    original export certificate of  airworthiness,  as of January 12, 2017
    (the effective date  of AD 2016-24-03):  Within 600 flight  hours or 4
    months, whichever occurs first after  January 12, 2017, do a  detailed
    visual inspection for signs of cracks and corrosion of the barrel  nut
    and cradle,  in accordance  with paragraph  3.B., "Procedure,"  of the
    Accomplishment Instructions of  Bombardier Alert Service  Bulletin A84
    -55-04, Revision C, dated May 3, 2016.

(2) For airplanes that have less than 5,400 flight hours, and have been in
    -service for less  than 32 months  since the date  of issuance of  the
    original certificate of airworthiness or  the date of issuance of  the
    original export certificate of airworthiness,  as of January 12, 2017:
    Before the accumulation of 6,000 total flight hours or 36 months since
    the date of issuance of  the original certificate of airworthiness  or
    the  date  of   issuance  of  the   original  export  certificate   of
    airworthiness, whichever occurs first, do a detailed visual inspection
    of the barrel nut for signs of cracks and corrosion of the barrel  nut
    and cradle,  in accordance  with paragraph  3.B., "Procedure,"  of the
    Accomplishment Instructions  of  Bombardier Alert Service Bulletin A84
    -55-04, Revision C, dated May 3, 2016.

(h) RETAINED CORRECTIVE ACTIONS, DETAILED INSPECTION,  AND  REPETITIVE IN-
    SPECTIONS, WITH NEW SERVICE INFORMATION,  REFERENCE TO TERMINATING AC-
    TION, AND REFERENCE TO CORRECTIVE ACTIONS

    This paragraph restates the requirements of paragraph (h)  of AD 2016-
    24-03, with new service information and terminating action.  Depending
    on the findings of any  inspection required by paragraphs (g)  and (j)
    of this AD,  do the applicable  actions in paragraphs  (h)(1), (h)(2),
    (h)(3), and (h)(4) of this AD. Accomplishment of the actions  required
    by paragraphs (l)  and (m) of  this AD, as  applicable, terminates the
    requirements of this paragraph.

(1) If any barrel nut or cradle is found cracked or broken, before further
    flight, replace the barrel nut and associated hardware, in  accordance
    with paragraph 3.B.,  "Procedure," of the  Accomplishment Instructions
    of Bombardier Service Bulletin  84-55-08, Revision A, dated  August 2,
    2017.

(i) Concurrently with the replacement of any barrel nut, do a detailed in-
    spection  for corrosion  and damage  of the  bore of  the fitting,  in
    accordance  with paragraph  3.B., "Procedure,"  of the  Accomplishment
    Instructions  of  Bombardier Service Bulletin  84-55-08,  Revision  A,
    dated August 2, 2017, and, before further flight, repair all corrosion
    and damage, in accordance  with Bombardier Repair Drawing  (RD) 8/4-55
    -1143, Issue 1, dated May 21, 2015. If the bore of the fitting  cannot
    be repaired  in accordance  with Bombardier  RD 8/4-55-1143,  Issue 1,
    dated May 21, 2015,  accomplish corrective actions in  accordance with
    the procedures specified in paragraph (q)(2) of this AD.

(ii) Within 600 flight hours or 4 months,  whichever  occurs  first, after
     the replacement of a cracked barrel nut, replace the remaining barrel
     nuts and  their associated  hardware at  the horizontal-stabilizer-to
     -vertical-stabilizer attachment joints, in accordance with  paragraph
     3.B., "Procedure," of  the Accomplishment Instructions  of Bombardier
     Service Bulletin 84-55-08, Revision A, dated August 2, 2017.

(2) If any corrosion is found on any barrel nut on the front  or rear-spar
    joints, before further  flight, replace the  barrel nut in  accordance
    with paragraph 3.B.,  "Procedure," of the  Accomplishment Instructions
    of Bombardier Service Bulletin  84-55-08, Revision A, dated  August 2,
    2017,  or  accomplish  corrective  actions  in  accordance  with   the
    procedures specified in paragraph (q)(2) of this AD.

(3) If any corrosion above level 1, as defined in Bombardier Alert Service
    Bulletin A84-55-04,  Revision C,  dated May 3, 2016,  is  found  on  a
    barrel nut at the mid-spar  joint, before further flight, replace  the
    barrel nut and  accomplish corrective actions  in accordance with  the
    procedures specified in paragraph (q)(2) of this AD.

(4) If all corrosion found is at level 1 or below as defined in Bombardier
    Alert Service Bulletin A84-55-04, Revision C, dated May 3, 2016, on  a
    barrel nut at the mid-spar  joint, repeat the inspection specified  in
    paragraph (g) of this AD at  intervals not to exceed 600 flight  hours
    or 4 months, whichever occurs  first, until completion of the  actions
    required by paragraph (k) of this AD.

(i) RETAINED PRELOAD INDICATING (PLI) WASHER CHECK,  WITH  NEW TERMINATING
    ACTION

    This paragraph restates the requirements of paragraph (i)  of AD 2016-
    24-03, with  new terminating  action. For  airplanes with  PLI washers
    installed at  the front  and rear-spar  joints, before  further flight
    after accomplishing any inspection  required by paragraph (g)  of this
    AD and all applicable corrective actions required by paragraph (h)  of
    this AD,  check the  bolt preload,  and do  all applicable  corrective
    actions,  in  accordance  with  paragraph  3.B.,  "Procedure,"  of the
    Accomplishment Instructions of  Bombardier Alert Service  Bulletin A84
    -55-04, Revision C,  dated May 3, 2016.  Do all  applicable corrective
    actions before further flight. Accomplishment of the actions  required
    by paragraphs (l)  and (m) of  this AD, as  applicable, terminates the
    requirements of this paragraph.

(j) RETAINED REPETITIVE INSPECTION INTERVAL, WITH NEW TERMINATING ACTION

    This paragraph restates the requirements of paragraph (j)  of AD 2016-
    24-03, with new terminating action. Repeat the inspection and  preload
    check required by paragraphs (g) and  (i) of this AD at intervals  not
    to exceed  3,600 flight  hours or  18 months,  whichever occurs first,
    except as provided by paragraph (k) of this AD. Accomplishment of  the
    actions required by paragraphs (l) and (m) of this AD, as  applicable,
    terminates the requirements of this paragraph.

(k) RETAINED OPTIONAL BARREL NUT REPLACEMENT, WITH NEW SERVICE INFORMATION

    This paragraph restates the provisions of paragraph (k) of AD 2016-24-
    03, with new  service information. Inspection  and replacement of  all
    barrel   nuts   at   the  horizontal-stabilizer-to-vertical-stabilizer
    attachment joints, in accordance with paragraph 3.B., "Procedure,"  of
    the Accomplishment Instructions  of Bombardier Service  Bulletin 84-55
    -08,  Revision A,  dated  August 2, 2017, extends  the next inspection
    required by paragraph (j) of this  AD to within 6,000 flight hours  or
    36 months,  whichever occurs first,  after accomplishing  the replace-
    ment.

(l) NEW REQUIREMENT OF THIS AD: SEALING DISK INSTALLATION

    Within 8,000 flight hours or 48 months, whichever occurs first,  after
    the effective date of this AD, install a sealing disk at the  mid-spar
    location of the vertical stabilizer in accordance with paragraph 3.B.,
    "Procedure," of the Accomplishment Instructions of Bombardier  Service
    Bulletin  84-55-06,  dated  January 31, 2017.  Accomplishment  of  the
    actions required by paragraphs (l) and (m) of this AD, as  applicable,
    terminates the requirements  of paragraphs (h),  (i), and (j)  of this
    AD.

(m) NEW REQUIREMENT OF THIS AD: REPLACEMENT OF DSC228 SERIES BARREL NUTS

    For Bombardier, Inc., Model DHC-8-400, -401 and -402 airplanes, serial
    numbers 4001 through 4524 inclusive:  Within 8,000 flight hours or  48
    months, whichever occurs first, after  the effective date of this  AD,
    replace all DSC228 series barrel nuts at the  horizontal-stabilizer-to
    -vertical-stabilizer  attachment  joints with  B0203073  series barrel
    nuts  in   accordance  with   paragraph  3.B.,   "Procedure,"  of  the
    Accomplishment Instructions of  Bombardier Service Bulletin  84-55-08,
    Revision  A,  dated  August 2,  2017.  Accomplishment  of the  actions
    required  by  paragraphs  (l)  and  (m)  of  this  AD,  as applicable,
    terminates the requirements  of paragraphs (h),  (i), and (j)  of this
    AD.

(n) PARTS INSTALLATION PROHIBITION

    After modification of  an airplane as  required by paragraphs  (l) and
    (m) of this AD,  no person may install  a DSC228 series barrel  nut at
    the horizontal-stabilizer-to-vertical-stabilizer  attachment joint  on
    the modified airplane.

(o) TERMINATING ACTIONS

    Accomplishment of the  actions required by  paragraphs (l) and  (m) of
    this AD, as applicable, terminates the requirements of paragraphs (h),
    (i), and (j) of this AD.

(p) CREDIT FOR PREVIOUS ACTIONS

(1) This paragraph provides credit for actions required  by paragraphs (g)
    (1), (g)(2),  (h)(1), (h)(1)(i),  (h)(1)(ii), (h)(2),  (h)(3), (h)(4),
    (i), and (k) of  this AD, if those  actions were performed before  the
    effective date of this AD using the service information identified  in
    paragraphs (p)(1)(i) through (p)(1)(iii) of this AD.

(i) Bombardier Alert Service Bulletin A84-55-04, dated May 21, 2015, which
    is not incorporated by reference in this AD.

(ii) Bombardier Alert Service Bulletin A84-55-04 Revision A, dated June 2,
     2015, which is not incorporated by reference in this AD.

(iii) Bombardier Alert Service Bulletin A84-55-04, Revision B,  dated July
      30, 2015, which is not incorporated by reference in this AD.

(2) This paragraph provides credit for actions required  by paragraphs (h)
    (1),  (h)(1)(i), (h)(1)(ii),  (h)(2),  and  (k) of  this AD,  if those
    actions were performed before the effective date of this AD using  the
    service information identified in paragraphs (p)(2)(i) and  (p)(2)(ii)
    of this AD.

(i) Bombardier Service Bulletin 84-55-08, dated January 27, 2017, which is
    not incorporated by reference in this AD.

(ii) Bombardier Alert Service Bulletin A84-55-04, Revision C, dated May 3,
     2016, which was incorporated by reference in AD 2016-24-03.

(q) OTHER FAA AD PROVISIONS

(1) Alternative Methods of Compliance (AMOCs):  The Manager,  New York ACO
    Branch,  FAA,  has the authority to approve AMOCs for this AD,  if re-
    quested 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 informa-
    tion directly to the manager  of the certification office,  send it to
    ATTN: Program Manager,  Continuing Operational Safety,  FAA,  New York
    ACO Branch,  1600 Stewart Avenue, Suite 410, Westbury, NY 11590; tele-
    phone 516-228-7300; fax 516-794-5531.

(i) Before using any approved AMOC,  notify your appropriate principal in-
    spector,  or  lacking a principal inspector,  the manager of the local
    flight standards district office/certificate holding district office.

(ii) AMOCs approved previously for AD 2016-24-03 are approved as AMOCs for
     the corresponding provisions of this AD.

(2) Contacting the Manufacturer:  For any requirement in this AD to obtain
    corrective  actions   from  a   manufacturer,  the   action  must   be
    accomplished using  a method  approved by  the Manager,  New York  ACO
    Branch, FAA; or Transport Canada Civil Aviation (TCCA); or Bombardier,
    Inc.'s TCCA  Design Approval  Organization (DAO).  If approved  by the
    DAO, the approval must include the DAO-authorized signature.

(r) RELATED INFORMATION

(1) Refer  to  Mandatory Continuing Airworthiness Information (MCAI)  TCCA
    Airworthiness Directive CF-2015-13R1, dated June 26, 2017, for related
    information.  This MCAI may be found in the AD docket  on the internet
    at http://www.regulations.gov by searching for and locating Docket No.
    FAA-2018-0160.

(2) For more information about this AD, contact Aziz Ahmed, Aerospace Eng-
    ineer,  Airframe and Mechanical Systems Section,  FAA,  New  York  ACO
    Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;  telephone
    516-228-7329; fax 516-794-5531.

(3) For service information  identified  in this AD,  contact  Bombardier,
    Inc.,  Q-Series Technical Help Desk,  123 Garratt Boulevard,  Toronto,
    Ontario M3K 1Y5, Canada;  telephone 416-375-4000; fax 416-375-4539; e-
    mail thd.qseries@aero.bombardier.com;  internet http://www.bombardier.
    com.  You may view  this service information  at  the  FAA,  Transport
    Standards Branch, 2200 South 216th St, Des Moines, WA. For information
    on the availability of this material at the FAA, call 206-231-3195.

Issued in Renton, Washington, on March 2, 2018.  Michael Kaszycki,  Acting
Director, System Oversight Division, Aircraft Certification Service.

DATES: We must receive comments on this proposed AD by April 23, 2018.
PREAMBLE 

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0160; Product Identifier 2017-NM-139-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to supersede Airworthiness Directive (AD) 2016-24-
03, which applies to certain Bombardier, Inc., Model DHC-8-400 series
airplanes. AD 2016-24-03 requires repetitive detailed inspections of
barrel nuts and cradles, a check of the bolt torque of the preload
indicating (PLI) washers, and corrective actions if necessary. Since we
issued AD 2016-24-03, the manufacturer has developed a modification
that, when incorporated, terminates the repetitive inspections. This
proposed AD would require modifying the airplane by installing a
sealing disk to a certain location and replacing certain barrel nuts.
We are proposing this AD to address the unsafe condition on these
products.

DATES: We must receive comments on this proposed AD by April 23, 2018.

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
Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard,
Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000; fax 416-375-
4539; email thd.qseries@aero.bombardier.com; internet http://www.
bombardier.com. You may view this referenced service information at
the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines,
WA. For information on the availability of this material at the FAA,
call 206-231-3195.

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-2018-0160;
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
Operations office (telephone 800-647-5527) is in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Aziz Ahmed, Aerospace Engineer,
Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7329;
fax 516-794-5531.

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-2018-0160;
Product Identifier 2017-NM-139-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 based on 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 issued AD 2016-24-03, Amendment 39-18720 (81 FR 88623, December
8, 2016) ("AD 2016-24-03"), for certain Bombardier, Inc., Model DHC-
8-400 series airplanes. AD 2016-24-03 requires repetitive detailed
inspections of barrel nuts and cradles, a check of the bolt torque of
the PLI washers, and corrective action if necessary. AD 2016-24-03
resulted from reports of cracked and corroded barrel nuts found at the
mid-spar location of the horizontal-stabilizer-to-vertical-stabilizer
attachment joint. We issued AD 2016-24-03 to detect and correct cracked
and corroded barrel nuts, which could compromise the structural
integrity of the vertical-stabilizer attachment joints and lead to loss
of control of the airplane.

Actions Since AD 2016-24-03 Was Issued


Since we issued AD 2016-24-03, Bombardier, Inc. has issued new
service information that describes a modification. We have determined
that accomplishment of this modification will address the unsafe
condition and terminate the repetitive inspections required by AD 2016-
24-03. This modification was applied to certain airplanes in
production.

Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2015-13R1, dated June 26, 2017 (referred to after this as the Mandatory
Continuing Airworthiness Information, or "the MCAI"), to correct an
unsafe condition for certain Bombardier, Inc., Model DHC-8-400 series
airplanes. The MCAI states:

There has been one in-service report of a cracked and corroded
barrel nut, part number (P/N) DSC228-12, found at the mid-spar
location of the horizontal stabilizer to vertical stabilizer
attachment joint. There have also been two other reports of corroded
barrel nuts found at mid-spar locations.

Preliminary investigation determined that the cracking is
initiated by corrosion. Further investigation confirmed that the
corrosion was caused by inadequate cadmium plating on the barrel
nuts. Failure of the barrel nuts could compromise the structural
integrity of the joint and could lead to loss of control of the
aeroplane.

The original version of this [Canadian] AD was issued to mandate
the initial and repetitive inspections of the barrel nuts [and
cradles for cracks and corrosion] at each of the horizontal
stabilizer to vertical stabilizer attachment joints.

Revision 1 of this [Canadian] AD is issued to terminate the
repetitive inspection requirement by requiring the incorporation of
a modification to install a sealing disc at the middle spar location
of the horizontal stabilizer to vertical stabilizer attachment
joint, and the replacement of the DSC228 series barrel nuts with
B0203073 series barrel nuts that are more resistant to corrosion.
The applicability has been changed to account for the introduction
of the modifications in production.

Required actions include a bolt preload check of the PLI washers
and applicable corrective actions (retorque of the bolts and
replacement of the barrel nut), a detailed inspection of cracked or
broken barrel nuts for damaged bores of the fittings, replacement of
discrepant barrel nuts (those with signs of structural damaged,
corrosion, or cracking, or having a part number other than B0203073
series), adding an aluminum sealing disk to the
mid-spar barrel nut bore, and repair of damage and corrosion.

You may examine the MCAI in the AD docket on the internet at http:
//www.regulations.gov by searching for and locating Docket No. FAA-2018-
0160.

Explanation of Changes From AD 2016-24-03

In paragraph (h)(2) of AD 2016-24-03, we stated ". . . replace the
barrel nut accomplish corrective actions in accordance with [methods
approved by the FAA, TCCA, or Bombardier's TCCA Design Approval
Organization]." We intended to match the language in the MCAI and
allow operators to either replace the discrepant barrel nut in
accordance with the applicable service information or to request an
alternative method of compliance (AMOC). In addition, we left
"paragraph (h)(2)" out of the credit paragraph in AD 2016-24-03. We
have updated the retained requirements in this proposed AD to correct
those errors.

Related Service Information Under 1 CFR Part 51

Bombardier, Inc. has issued the following service information.

Bombardier Service Bulletin 84-55-06, dated January 31,
2017. The service information describes procedures for installing an
aluminum sealing disk at the mid-spar location of the vertical
stabilizer.

Bombardier Service Bulletin 84-55-08, Revision A, dated
August 2, 2017. The service information describes procedures for an
inspection for part number and damage of the barrel nuts at the
horizontal-to-vertical-stabilizer attachment joints, and replacement of
discrepant parts.

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 and Requirements of This Proposed AD

This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to our bilateral agreement with the State of Design Authority, we have
been notified of the unsafe condition described in the MCAI and service
information referenced above. We are proposing this AD because we
evaluated all pertinent information and determined an unsafe condition
exists and is likely to exist or develop on other products of the same
type design.

Differences Between This Proposed AD and the MCAI or Service
Information


The applicability of Canadian AD CF-2015-13R1, dated June 26, 2017,
is limited to Bombardier, Inc., Model DHC-8-400, -401 and -402
airplanes, serial numbers 4001 through 4547. However, the applicability
of this proposed AD includes Bombardier, Inc., Model DHC-8-400, -401
and -402 airplanes, serial numbers 4001 and subsequent. Because the
affected barrel nuts are rotable parts, we have determined that
discrepant parts could later be installed on airplanes that were
initially delivered with B0203073 series barrel nuts, thereby
subjecting those airplanes to the unsafe condition.

Costs of Compliance

We estimate that this proposed AD affects 54 airplanes of U.S.
registry. We estimate the following costs to comply with this proposed
AD:

Estimated Costs

Action
Labor cost
Parts cost
Cost per product
Cost on U.S. operators
Inspections (retained actions from AD 2016-24-03) 8 work-hours x $85 per hour = $680 $0 $680 $36,720
Sealing disk installation (new proposed action) 4 work-hours x $85 per hour = $340 781 1,121 60,534
Replacement of DSC228 series barrel nuts (new proposed action) 2 work-hours x $85 per hour = $170 2,236 2,406 129,924

We estimate the following costs to do any necessary replacements
that would be required based on the results of the inspection. We have
no way of determining the number of aircraft that might need these
replacements:

On-Condition Costs

Action
Labor cost
Parts cost
Cost per product
Replacement (retained action from AD 2016-24-03) 2 work-hours x $85 per hour = $170 $8,881 $9,051

We have received no definitive data that would enable us to provide
cost estimates for the on-condition actions specified in this proposed
AD.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. "Subtitle VII: Aviation
Programs," describes in more detail the scope of the Agency's
authority.

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.

This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has
delegated the authority to issue ADs applicable to transport category
airplanes to the Director of the System Oversight Division.

Regulatory Findings

We determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect on the States, on the relationship
between the national Government and the States, or on the distribution
of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify this proposed
regulation:

1. Is not a "significant regulatory action" under Executive Order
12866;

2. Is not a "significant rule" under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]


2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD)
2016-24-03, Amendment 39-18720 (81 FR 88623, December 8, 2016), and
adding the following new AD: