Tdata AD

preamble attached >>>	ADs updated daily at www.Tdata.com
2022-03-15	VARIOUS AIRPLANES: Amendment 39-21932; Docket No. FAA-2021-0715; Project Identifier AD-2021-00259-A.

(a) EFFECTIVE DATE

    This airworthiness directive (AD) is effective March 21, 2022.

(b) AFFECTED ADS

    None.

(c) APPLICABILITY

    This AD applies to all serial numbers of the airplane models listed in
    table  1 to  paragraph (c),  certificated  in  any category,  that are
    either:

(1) Modified with  a  Garmin G3X Touch Electronic Flight Instrument System
    under Supplemental Type Certificate (STC) No. SA01899WI,  installed in
    accordance  with Master Drawing List (MDL)  Document No. 005-01320-00,
    Revision 9 or earlier,  interfaced with a Garmin Engine Adapter GEA 24
    connected to resistive fuel probes; or

(2) Modified  with  a  Garmin GI 275 Multi-Function Display  under STC No.
    SA02658SE, installed  in accordance  with MDL  Revision 9  or earlier,
    interfaced with a Garmin Engine Adapter GEA 24 connected to  resistive
    fuel probes.

Note 1 to paragraph (c):  Garmin Mandatory STC Service Bulletin  No. 2134,
Revision A and Garmin Mandatory STC Service Bulletin No. 2135, Revision A,
both dated April 23, 2021,  contain  information  for  how to determine if
your airplane has a resistive probe interface.

                TABLE 1 TO PARAGRAPH (C) — AFFECTED AIRPLANES             
    ______________________________________________________________________
    TYPE CERTIFICATE HOLDER         AIRPLANE MODEL
    ______________________________________________________________________
    Aermacchi S.p.A.                F.260, F.260B, F.260C, F.260D, F.260E,
                                    F.260F, S.205-18/F, S.205-18/R, S.205-
                                    20/F, S.205-20/R, S.205-22/R, S.208,
                                    and S.208A

    Aeronautica Macchi S.p.A./      AM-3
    Aerfer-Industrie Aerospaziali
    Meridionali S.p.A.

    Aerostar Aircraft Corporation   PA-60-600 (Aerostar 600), PA-60-601
                                    (Aerostar 601), PA-60-601P (Aerostar
                                    601P), and PA-60-602P (Aerostar 602P)

    Air Tractor, Inc.               AT-401

    Alexandria Aircraft, LLC        14-19, 14-19-2, 14-19-3, 14-19-3A, 17-
                                    30, 17-30A, 17-31, 17-31A, 17-31ATC,
                                    and 17-31TC

    Alpha Aviation Concept Limited  R2160

    American Champion Aircraft      402, 7EC, 7ECA, 7FC, 7GC, 7GCA, 7GCAA,
    Corp.                           7GCB, 7GCBA, 7GCBC, 7KCAB, 8GCBC, and
                                    8KCAB


    Aviat Aircraft Inc.             A-1, A-1A, A-1B, A-1C-180, A-1C-200,
                                    S1S, S-1T, S-2, S-2A, S-2B, S-2C, and
                                    S-2S

    Bellanca Aircraft Corporation   14-13, 14-13-2, 14-13-3, and 14-13-3W

    B-N Group Ltd.                  BN-2 and BN-2A

    CEAPR (type certificate         R3000/160
    previously held by APEX
    Aircraft)

    Cirrus Design Corporation       SR20, SR22, and SR22T

    Commander Aircraft Corporation  112, 112B, 112TC, 112TCA, 114, 114A,
                                    114B, and 114TC

    Cougar Aircraft Corporation     GA-7

    Cub Crafters, Inc.              CC19-180

    De Havilland Support Limited    B.121 Series 1, B.121 Series 2, and
                                    B.121 Series 3

    Diamond Aircraft Industries     DA20-A1, DA20-C1, DA 40, DA 40 F, and
    Inc.                            DA 40 NG

    Discovery Aviation, Inc.        XL-2

    Dynac Aerospace Corporation     Aero Commander Model 100, Aero
                                    Commander Model 100-180, Aero
                                    Commander Model 100A, Volaire Model
                                    10, and Volaire Model 10A

    EADS-PZL Warszawa-Okecie S.A.   PZL-104M Wilga 2000, PZL-104MA Wilga
                                    2000, PZL-KOLIBER 150A and PZL-KOLIBER
                                    160A

    Extra Flugzeugproduktions-und   EA-300, EA-300/200, EA-300/L, EA 300/
    Vertriebs GmbH                  LC, and EA-300/S

    FLS Aerospace (Lovaux) Ltd.     OA7 Optica Series 300

    Found Brothers Aviation         FBA Centennial 100
    Limited

    Frakes Aviation                 G-44 (Army OA-14, Navy J4F-2) (includ-
                                    ing SCAN Type 30) and G-44A

    FS 2003 Corporation             PA-12 and PA-12S

    Fuji Heavy Industries, Ltd.     FA-200-160, FA-200-180, and FA-200-
                                    180AO

    GA8 Airvan (Pty) Ltd.           GA8 and GA8-TC 320

    Gomolzig Flugzeug-und           AS 202/15 BRAVO, AS 202/18A BRAVO, and
    Maschinenbau GmbH               AS 202/18A4 BRAVO

    GROB Aircraft SE                G 115, G 115A, G 115B, G 115C,
                                    G 115C2, G 115D, and G 115D2

    Helio Aircraft Corporation      15A and 20

    Helio Alaska, Inc.              H-250, H-295 (USAF U10D), H-391 (USAF
                                    YL-24), H-391B, H-395 (USAF L28A or
                                    U-10B), H-395A, H-700, and HT295

    Interceptor Aircraft Inc.       200, 200A, 200B, 200C, 200D, and 400

    The King's Engineering          44 Angel, 4500-300, and 4500-300 Series
    Fellowship                      II

    Legend Aviation & Marine, LLC   UC-1

    Luscombe Aircraft Corporation   8, 8A, 8B, 8C, 8D, 8E, 8F, and T-8F

    Maule Aerospace Technology,     Bee Dee M-4, M-4, M-4-180C, M-4-180S,
    Inc.                            M-4-180T, M-4-180V, M-4-210, M-4-210C,
                                    M-4-210S, M-4-210T, M-4-220, M4-220C,
                                    M-4-220S, M-4-220T, M-4C, M4S, M-4T,
                                    M-5-180C, M-5-200, M-5-210C, M-5-
                                    210TC, M-5-220C, M-5-235C, M-6-180,
                                    M-6-235, M-7-235, M-7-235A, M-7-235B,
                                    M-7-235C, M-7-260, M-7-260C, M7-420A,
                                    M-7-420AC, M-8-235, M-9-235, MT-7-235,
                                    MT-7-260, MT-7-420, MX-7-160, MX-7-
                                    160C, MX-7-180, MX-7-180A, MX-7-180AC,
                                    MX-7-180B, MX-7-180C, MX-7-235, MX-7-
                                    420, MXT-7-160, MXT7-180, and MXT-7-
                                    180A

    Micco Aircraft Company, Inc.    MAC-125C, MAC-145, MAC-145A, and MAC-
                                    145B

    Mooney Aircraft Corporation     M22

    Mooney International            M20, M20A, M20B, M20C, M20D, M20E,
    Corporation                     M20F, M20G, M20J, M20K, M20L, M20M,
                                    M20R, M20S, and M20TN

    Nardi S.A.                      FN-333

    Pacific Aerospace Ltd.          FBA-2C, FBA-2C1, FBA-2C2, and FBA2C3

    Piaggio & C.                    P.136-L and P.136-L1

    Pilatus Aircraft Limited        PC-6, PC-6/350, PC-6/350-H1, PC-6/350-
                                    H2, PC-6-H1, and PC-6-H2

    Piper Aircraft, Inc.            PA-16, PA-16S, PA-18, PA-18-105
                                    (Special), PA-18-125 (Army L-21A),
                                    PA18-135, PA-18-150, PA-18A, PA-18A-
                                    135, PA-18A-150, PA-18AS-125, PA-18AS-
                                    135, PA-18AS-150, PA-18S, PA-18S-105
                                    (Special), PA-18S-125, PA-18S-135, PA-
                                    18S-150, PA-19 (Army L-18C), PA-19S,
                                    PA-20, PA-20-115, PA-20-135, PA-20S,
                                    PA-20S-115, PA-20S-135, PA-22, PA-22-
                                    108, PA-22-135, PA-22-150, PA-22-160,
                                    PA-22S-135, PA-22S-150, PA-22S-160,
                                    PA-23, PA-23-160, PA-23-235, PA-23-
                                    250, PA-23-250 (Navy UO-1), PA-24, PA-
                                    24-250, PA-24-260, PA-24-400, PA-28-
                                    140, PA-28-150, PA-28-151, PA-28-160,
                                    PA-28-161, PA-28-180, PA-28-181, PA-28
                                    -201T, PA-28-235, PA-28-236, PA-28R-
                                    180, PA-28R-200, PA-28R-201, PA-28R-
                                    201T, PA-28RT-201, PA-28RT-201T, PA-
                                    28S-160, PA-28S-180, PA-30, PA-31-300,
                                    PA-32-260, PA-32-300, PA-32-301, PA-32
                                    -301FT, PA-32-301T, PA-32-301XTC, PA-
                                    32R-300, PA-32R-301 (HP), PA-32R301
                                    (SP), PA-32R-301T, PA-32RT-300, PA-
                                    32RT-300T, PA-32S-300, PA-34-200, PA-
                                    34-200T, PA-34-220T, PA-38-112, PA39,
                                    PA-40, PA-44-180, PA-44-180T, PA-46-
                                    310P, PA-46-350P, PA-46R-350T, and PA-
                                    E23-250

    Polskie Zaklady Lotnicze        PZL M26 01
    Spolka zo.o

    Revo, Incorporated              Colonial Model C-1, Colonial Model
                                    C-2, Lake Model 250, Lake Model LA-4,
                                    and Lake Model LA-4-200

    Robert E. Rust, Jr.             DHC-1 Chipmunk Mk 21, DHC-1 Chipmunk
                                    Mk 22, and DHC-1 Chipmunk Mk 22A

    RUAG Aerospace Services GmbH    Do 27 Q-6, Do 28 A-1, and Do 28 B-1

    Sierra Hotel Aero, Inc.         Navion (Army L-17A), Navion A (Army
                                    L17B and L-17C), Navion B, Navion D,
                                    Navion E, Navion F, Navion G, and
                                    Navion H

    Sky Enterprises, Inc.           RC-3

    Slingsby Aviation Ltd.          T67M260

    SOCATA (type certificate        MS 880B, MS 885, MS 892A-150, MS 892E-
    currently held by Daher)        150, MS 893A, MS 893E, MS 894A, MS
                                    894E, Rallye 100S, Rallye 150 ST,
                                    Rallye 150 T, Rallye 235C, Rallye 235
                                    E, TB9, TB 10, TB 20, TB 21 and TB 200

    Spartan Aircraft Company        7W (Army UC-71)

    Swift Museum Foundation, Inc.   GC-1A and GC-1B

    Symphony Aircraft Industries    OMF-100-160 and SA 160
    Inc.

    Textron Aviation Inc.           19A, 23, 35, 36, 50, 58, 76, 77, 95,
                                    120, 140, 140A, 150, 150A, 150B, 150C,
                                    150D, 150E, 150F, 150G, 150H, 150J,
                                    150K, 150L, 150M, 152, 170, 170A,
                                    170B, 172, 172A, 172B, 172C, 172D,
                                    172E, 172F (USAF T-41A), 172G, 172H
                                    (USAF T41A), 172I, 172K, 172L, 172M,
                                    172N, 172P, 172Q, 172R, 172RG, 172S,
                                    175, 175A, 175B, 175C, 177, 177A,
                                    177B, 177RG, 180, 180A, 180B, 180C,
                                    180D, 180E, 180F, 180G, 180H, 180J,
                                    180K, 182, 182A, 182B, 182C, 182D,
                                    182E, 182F, 182G, 182H, 182J, 182K,
                                    182L, 182M, 182N, 182P, 182Q, 182R,
                                    182S, 182T, 185, 185A, 185B, 185C,
                                    185D, 185E, 190, 195, 195A, 195B, 206,
                                    206H, 207, 207A, 210, 210-5 (205), 210
                                    -5A (205A), 210A, 210B, 210C, 210D,
                                    210E, 210F, 210G, 210H, 210J, 210K,
                                    210L, 210M, 210N, 210R, 310, 310A,
                                    310B, 310C, 310D, 310E, 310F, 310G,
                                    310H, 310I, 310J, 310J-1, 310K, 310L,
                                    310N, 310P, 310Q, 310R, 320, 320-1,
                                    320A, 320B, 320C, 320D, 320E, 320F,
                                    335, 336, 337, 337A, 337B, 337C, 337D,
                                    337E, 337F, 337G, 337H, 340, 340A, 35-
                                    33, 35-A33, 35-B33, 35-C33, 35-C33A,
                                    35R, 45 (Military YT-34), 56TC, 58A,
                                    58PA, 58TCA, 95-55, 95-A55, 95-B55, 95
                                    -B55A, 95-B55B, 95-C55, 95-C55A,
                                    A150K, A150L, A150M, A152, A185E,
                                    A185F, A23, A23-19, A23-24, A23A, A24,
                                    A24R, A35, A36, A36TC, A45 (Military
                                    T34A, B-45), A56TC, B19, B23, B24R,
                                    B35, B36TC, B50, B95, B95A, C23, C24R,
                                    C35, C50, D17S, D35, D45 (Military T-
                                    34B), D50E-5990, D55, D55A, D95A,
                                    E310H, E310J, E33, E33A, E33C, E35,
                                    E55, E55A, E95, F150F, F150G, F150H,
                                    F150J, F150K, F150L, F150M, F152,
                                    F172D, F172E, F172F, F172G, F172H,
                                    F172K, F172L, F172M, F172N, F172P,
                                    F177RG, F182P, F182Q, F33, F33A, F33C,
                                    F337E, F337F, F337G, F337H, F35,
                                    FA150K, FA150L, FA150M, FA152, FP172D,
                                    FR172E, FR172F, FR172G, FR172H,
                                    FR172J, FR172K, FR182, FRA150L,
                                    FRA150M, FT337E, FT337F, FT337GP,
                                    FT337HP, G33, G35, G36, G58, H35, J35,
                                    K35, LC40-550FG, LC41-550FG, LC42-
                                    550FG, M19A, M337B, M35, N35, P172D,
                                    P206, P206A, P206B, P206C, P206D,
                                    P206E, P210N, P210R, P337H, P35,
                                    R172E, R172F, R172G, R172H, R172J,
                                    R172K, R182, S35, SD17S, T182, T182T,
                                    T206H, T207, T207A, T210F, T210G,
                                    T210H, T210J, T210K, T210L, T210M,
                                    T210N, T210R, T240, T303, T310P,
                                    T310Q, T310R, T337B, T337C, T337D,
                                    T337E, T337F, T337G, T337H, T337H-SP,
                                    TP206A, TP206B, TP206C, TP206D,
                                    TP206E, TR182, TU206A, TU206B, TU206C,
                                    TU206D, TU206E, TU206F, TU206G, U206,
                                    U206A, U206B, U206C, U206D, U206E,
                                    U206F, U206G, V35, V35A, and V35B

    Topcub Aircraft, Inc.           CC18-180 and CC18-180A

    True Flight Holdings LLC        AA-1, AA-1A, AA-1B, AA-1C, AA-5, AA-
                                    5A, AA-5B, and AG-5B

    Twin Commander Aircraft LLC     500, 500-A, 520, 560, and 560-A

    Univair Aircraft Corporation    108, 108-1, 108-2, 108-3, 108-5, 415-
                                    C, 415-CD, 415-D, A-2, A2-A, E, F-1,
                                    F-1A, G, and M10

    Viking Air Limited              DHC-2 Mk.I, DHC-2 Mk.II, DHC-2 Mk.III,
                                    and TR-1

    Vulcanair S.p.A.                P.68, P.68 "Observer," P.68B, P.68C,
                                    P.68C-TC, P.68R, P.68 Observer 2,
                                    P.68TC Observer, and Vulcanair V1.0

    WACO Classic Aircraft           2T-1A, 2T-1A-1, and 2T-1A-2
    Corporation

    WSK PZL Mielec and              PZL M20 03
    OBR SK Mielec

    W.Z.D. Enterprises Inc          11A and 11E

    Zenair Ltd.                     CH2000

    Zlin Aircraft a.s.              Z-143L, Z-242L, and Zlin 526L
    ______________________________________________________________________

(d) SUBJECT

    Joint Aircraft System Component (JASC) Code 2841,  Fuel Quantity Indi-
    cator.

(e) UNSAFE CONDITION

    This AD was prompted by  reports of fuel quantity disparities  between
    the amount of fuel indicated and the actual amount of fuel. The FAA is
    issuing this AD  to ensure that  the amount of  fuel indicated is  the
    amount  of fuel  available. The  unsafe condition,  if not  addressed,
    could result in fuel starvation and engine shutdown which could result
    in the inability  to arrive at  the destination airport  or a suitable
    alternative airport.

(f) COMPLIANCE

    Comply with this AD within the compliance times specified,  unless al-
    ready done.

(g) ACTION

    Within 100 hours time-in-service after  the effective date of this  AD
    or within  12 months  after the  effective date  of this AD, whichever
    occurs  first,  modify  the  fuel  probe  interface  by  following the
    Modification  Instructions in  Garmin Mandatory  STC Service  Bulletin
    2134,  Revision  A, or  Garmin  Mandatory STC  Service  Bulletin 2135,
    Revision A, both dated April 23, 2021, whichever is applicable.

(h) ALTERNATIVE METHODS OF COMPLIANCE (AMOCS)

(1) The  Manager,  Wichita ACO Branch,  FAA,  has the authority to approve
    AMOCs for this AD, if requested  using the procedures found in 14  CFR
    39.19. In  accordance with  14 CFR  39.19, send  your request  to your
    principal  inspector  or  local Flight  Standards District  Office, as
    appropriate. If  sending information  directly to  the manager  of the
    certification  office,  send  it  to  the  attention  of  the   person
    identified in paragraph (i) of this AD.

(2) 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.

(i) RELATED INFORMATION

    For more information  about this  AD,  contact  Kevin Marks,  Aviation
    Safety Engineer, Wichita ACO Branch,  FAA, 1801 Airport Road, Wichita,
    KS 67209; phone: (316) 946-4153; email: kevin.marks@faa.gov or Wichita
    -COS@faa.gov.

(j) MATERIAL INCORPORATED BY REFERENCE

(1) The Director of the Federal Register  approved  the  incorporation  by
    reference of the service information  listed in this paragraph under 5
    U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information  as applicable to do the actions
    required by this AD, unless the AD specifies otherwise.

(i) Garmin Mandatory STC Service Bulletin 2134 Revision A, dated April 23,
    2021.

(ii) Garmin Mandatory STC Service Bulletin 2135,  Revision A,  dated April
     23, 2021.

(3) For service information identified in this AD, contact Garmin Interna-
    tional, Garmin Aviation Support, 1200 E 151st Street, Olathe, KS 66062
    phone: (866) 739-5687; email avionics@garmin.com; website https://fly.
    garmin.com/fly-garmin/support/.

(4) You may view this service information at the FAA,  Airworthiness Prod-
    ucts Section, Operational Safety Branch,  901 Locust,  Kansas City, MO
    64106. For information on the availability of this material at the FAA
    call (817) 222-5110.

(5) You may view this service information  that is incorporated  by refer-
    ence at the National Archives and Records Administration  (NARA).  For
    information on the availability of this material  at NARA,  email: fr.
    inspection@nara.gov,   or   go  to:  https://www.archives.gov/federal-
    register/cfr/ibr-locations.html.

Issued on January 25, 2022. Lance T Gant, Director, Compliance & Airworth-
iness Division, Aircraft Certification Service.

FOR FURTHER INFORMATION CONTACT: Kevin Marks,  Aviation  Safety  Engineer,
Wichita ACO Branch,  FAA,  1801 Airport Road,  Wichita, KS  67209;  phone:
(316) 946-4153; email: kevin.marks@faa.gov or Wichita-COS@faa.gov.

PREAMBLE

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0715; Project Identifier AD-2021-00259-A;
Amendment 39-21932; AD 2022-03-15]
RIN 2120-AA64

Airworthiness Directives; Various Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
various airplanes modified with certain configurations of Garmin G3X
Touch Electronic Flight Instrument System installed per Supplemental
Type Certificate (STC) No. SA01899WI or Garmin GI 275 Multi-Function
Display (MFD) installed per STC No. SA02658SE. This AD was prompted by
a report of a fuel quantity disparity between the amount of fuel
indicated and the actual amount of fuel. This AD requires modifying the
resistive fuel probe interface. The FAA is issuing this AD to address
the unsafe condition on these products.

DATES: This AD is effective March 21, 2022.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of March 21,
2022.

ADDRESSES: For service information identified in this final rule,
contact Garmin International, Garmin Aviation Support, 1200 E 151st
Street, Olathe, KS 66062; phone: (866) 739-5687; email:
avionics@garmin.com; website: https://fly.garmin.com/fly-garmin/support/.
You may view this service information at the FAA,
Airworthiness Products Section, Operational Safety Branch, 901 Locust,
Kansas City, MO 64106. For information on the availability of this
material at the FAA, call (817) 222-5110. It is also available at
https://www.regulations.gov by searching for and locating Docket No.
FAA-2021-0715.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0715; or in person at
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The AD docket contains this final rule, any
comments received, and other information. The address for Docket
Operations is U.S. Department of Transportation, Docket Operations, M-
30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue
SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Kevin Marks, Aviation Safety Engineer,
Wichita ACO Branch, FAA, 1801 Airport Road, Wichita, KS 67209; phone:
(316) 946-4153; email: kevin.marks@faa.gov or Wichita-COS@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to various airplanes
modified with certain configurations of Garmin G3X Touch Electronic
Flight Instrument System installed per STC No. SA01899WI or Garmin GI
275 MFD installed per STC No. SA02658SE. The NPRM published in the
Federal Register on August 27, 2021 (86 FR 48070). The NPRM was
prompted by notification of a Piper production line issue with the
installation of a Garmin G3X Touch Electronic Flight Instrument System
installed under STC No. SA01899WI. After calibration and fueling the
airplane to a known level, the flight crew noted that the fuel quantity
indicator displayed a higher level of fuel.
The Garmin G3X Touch Electronic Flight Instrument System, when
interfaced with the Garmin GEA 24 (Engine Airframe Adapter) for display
of the fuel quantity, uses a 1K ohm resistor inline between the GEA 24
and the airplane fuel quantity resistance style sending unit (float).
This resistor provides lightning protection to the fuel tank as
required by 14 CFR 23.954.
Use of the 1K resistor causes a GEA error when the GEA 24 or
resistor is subjected to significantly hotter or colder temperatures
than the temperature at which the fuel gauges were calibrated during
installation. The farther the actual (ambient) temperature of the GEA
24 or resistor is from the temperature of the fuel quantity
calibration, the larger the error. The lower the operating resistance
of the fuel sending unit, the larger the error. The largest errors
occur in installations with fuel sending units having an operational
range less than 100 ohms. The Garmin GI 275 MFDs installed under STC
No. SA02658SE, when interfaced with the Garmin GEA 24 for display of
the fuel quantity, is also subject to this unsafe condition.
The displayed fuel quantity can have an error as much as four
gallons/fuel tank with the display indicating four gallons with an
empty tank. In the NPRM, the FAA proposed to require modifying the
resistive fuel probe interface. The FAA is issuing this AD to prevent
fuel starvation and engine shutdown, which could result in the
inability to arrive at the destination airport or a suitable
alternative airport.

Discussion of Final Airworthiness Directive

Comments

The FAA received comments from Garmin. The following presents the
comments received on the NPRM and the FAA's response to each comment.

Requests Regarding Background Information

Garmin requested the FAA correct certain information in the
preamble. In the NPRM, the FAA stated that use of the 1K resistor
causes a GEA error when the resistor temperature changes. According to
Garmin, using the 1K resistor causes a GEA error when the GEA 24
temperature changes. Garmin further noted that 1k resistors are
installed near the GEA 24 plug and are exposed to the same ambient
temperatures.
The FAA agrees with correcting the preamble and has changed this
final rule to clarify that a GEA error results from the GEA 24 being
subjected to significantly hotter or colder temperatures than the
temperature at which the fuel gauges were calibrated during
installation. The FAA disagrees with the requested changes regarding
the location of the resistors. The commenter's request is not supported
by the information in the installation manual, which does not require
the resistor to be installed near the GEA 24.
Garmin also requested that the FAA remove the exact error amount
(i.e., four gallons) between the displayed fuel quantity and the actual amount of
fuel. Garmin stated that due to variations in different aircraft system
configurations, this amount could be misleading.
Removing the reference to 4 gallons would minimize the potential
magnitude of the error and the need for AD action. The FAA did not
change this AD based on this comment.
Garmin noted a typographical error in that the NPRM referred to
``MFDS'' instead of ``MFDs.''
The FAA agrees and has corrected all references to MFDs
accordingly.

Request Regarding Unsafe Condition

Garmin requested that the FAA change the description of the
inevitable consequence of the unsafe condition. In the NPRM, the FAA
stated the unsafe condition, if not addressed, could result in fuel
starvation and engine shutdown with consequent loss of airplane
control. Garmin stated that this incorrectly implies that loss of
airplane control is the inevitable consequence of fuel starvation and
engine shutdown. Garmin requested the FAA revise the preamble to state
that loss of airplane control is one of many possible outcomes.
The FAA agrees that loss of control is not an inevitable result of
fuel starvation. In the context of this event, the end level effect is
the loss of powered flight to the destination airport. Accordingly, the
FAA has revised the background section of the preamble and the unsafe
condition paragraph of the AD to reflect that fuel starvation and
engine shutdown could result in the inability to arrive at the
destination airport or a suitable alternative airport.

Request Regarding Applicability

Garmin requested the FAA revise the AD to remove several airplane
models that are not subject to the unsafe condition. Garmin listed
these models as follows: The Boeing Company Model AT-6 (Navy SNJ-2),
AT-6A (Navy SNJ-3), AT-6B, AT-6C (Navy SNJ-4), AT-6D (Navy SNJ-5), AT-
6F (Navy SNJ-6), BC- 1A, Navy SNJ-7, and T-6G; Cessna Aircraft Company
Model T-50 (Army AT-17 and UC-78 series, Navy JRC-1); Costruzioni
Aeronautiche Tecnam S.P.A. Model P2006T; Daher Aircraft Design, LLC
(type certificate previously held by Quest Aircraft Design, LLC) Model
Kodiak 100; EADS-PZL Warszawa-Ok[eogon]cie S.A. Model PZL-104 Wilga 80;
Helio Alaska, Inc. Model H-800; Howard Aircraft Foundation Model DGA-
15J (Army UC-70B), DGA-15P (Army UC-70, Navy GH-1, GH-2, GH-3, NH-1),
and DGA-15W; Textron Aviation Inc. Model G17S; Thrush Aircraft, LLC
Model 600 S-2D, S2R, S2R-R1340, S2R-Rl820, S2R-R3S, and S2R-T34; and
Waco Aircraft Company Model YMF airplanes.
The FAA agrees and has revised the list of applicable models
accordingly.

Conclusion

The FAA reviewed the relevant data, considered any comments
received, and determined that air safety requires adopting this AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products. Except for the changes described
previously, this AD is adopted as proposed in the NPRM. None of the
changes will increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Garmin Mandatory STC Service Bulletin 2134,
Revision A, and Garmin Mandatory STC Service Bulletin 2135, Revision A,
both dated April 23, 2021. This service information specifies
procedures for modifying the GEA 24 resistive fuel probe interface.
These documents are distinct since they apply to different STCs. 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

The FAA also reviewed Master Drawing List (MDL) Document No. 005-
01320-00, Revision 10, for STC No. SA01899WI; and MDL Drawing No. 005-
01208-41, Revision 10, for STC No. SA02658SE; both dated April 23,
2021. This service information contains the type design data for
installation of the STC. MDL Document No. 005-01320-00, Revision 10,
dated April 23, 2021, introduces a new fuel quantity interface and
configuration to eliminate the unsafe condition described previously.

Costs of Compliance

The FAA estimates that this AD affects 920 airplanes of U.S.
registry.
The FAA estimates the following costs to comply with this AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per airplane	Cost on U.S. operators
Modify fuel probe interface and recalibrate the fuel system	8 work-hours x $85 per hour = $680	$10	$690	$634,800

The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some of the costs of this AD
may be covered under warranty, thereby reducing the cost impact on
affected operators.

Authority for This Rulemaking

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

Regulatory Findings

This AD will not have federalism implications under Executive Order
13132. This AD will 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 that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Will not affect intrastate aviation in Alaska, and
(3) 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 Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

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

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

Sec. 39.13 [Amended]

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