[Federal Register Volume 68, Number 249 (Tuesday, December 30, 2003)]
[Proposed Rules]
[Pages 75174-75179]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-31978]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-CE-39-AD]
RIN 2120-AA64


Airworthiness Directives; GARMIN International Inc. GTX 330 Mode 
S Transponders and GTX 330D Diversity Mode S Transponders

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain GARMIN International Inc. GTX 330/GTX 330D Mode S 
transponders. This proposed AD would require you to install GTX 330/
330D Software Upgrade Version 3.03. This proposed AD is the result of 
observations that the GTX 330 and GTX 330D may detect, from other 
aircraft, the S1 (suppression) interrogating pulse below the Minimum 
Trigger Level (MTL) and, in some circumstances, not reply. The GTX 330/
330D should still reply even if it detects

[[Page 75175]]

S1 interrogating pulses below the MTL. We are issuing this proposed AD 
to prevent interrogating aircraft from possibly receiving inaccurate 
replies due to suppression from aircraft equipped with the GTX 330/330D 
Mode S Transponders when the pulses are below the MTL. The inaccurate 
replies could result in reduced vertical separation or unsafe TCAS 
resolution advisories.

DATES: We must receive any comments on this proposed AD by February 3, 
2004.

ADDRESSES: Use one of the following to submit comments on this proposed 
AD:
    [sbull] By mail: FAA, Central Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 2003-CE-39-AD, 901 Locust, Room 
506, Kansas City, Missouri 64106.
    [sbull] By fax: (816) 329-3771.
    [sbull] By e-mail: [email protected]. Comments sent 
electronically must contain ``Docket No. 2003-CE-39-AD'' in the subject 
line. If you send comments electronically as attached electronic files, 
the files must be formatted in Microsoft Word 97 for Windows or ASCII.
    You may get the service information identified in this proposed AD 
from GARMIN International Inc., 1200 East 151st Street, Olathe, KS 
66062, 913-397-8200.
    You may view the AD docket at FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2003-CE-39-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. 
to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Roger A. Souter, FAA, Wichita Aircraft 
Certification Office (ACO), 1801 Airport Road, Room 100, Wichita, 
Kansas 67209; telephone: 316-946-4134; facsimile: 316-946-4107; email 
address: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

How Do I Comment on This Proposed AD?

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2003-CE-39-AD'' in the 
subject line of your comments. If you want us to acknowledge receipt of 
your mailed comments, send us a self-addressed, stamped postcard with 
the docket number written on it. We will date-stamp your postcard and 
mail it back to you.

Are There Any Specific Portions of This Proposed AD I Should Pay 
Attention To?

    We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. If you 
contact us through a nonwritten communication and that contact relates 
to a substantive part of this proposed AD, we will summarize the 
contact and place the summary in the docket. We will consider all 
comments received by the closing date and may amend this proposed AD in 
light of those comments and contacts.

Discussion

What Events Have Caused This Proposed AD?

    The GTX 330/GTX 330D may detect from other aircraft the S1 
(suppression) interrogating pulse below the MTL and, in some 
circumstances, does not reply. The GTX 330/330D should still reply even 
if it detects S1 interrogating pulses below the MTL. GARMIN 
International Inc. suspected the suppression problem after observation 
between GARMIN company aircraft that were equipped with the GTX 330 and 
Ryan Traffic and Collision Alert Device (TCAD). Engineering bench tests 
and test flights confirmed that this suppression problem existed.

What Are The Consequences If the Condition Is Not Corrected?

    Interrogating aircraft could possibly receive inaccurate replies 
due to suppression from aircraft equipped with the GTX 330/330D Mode S 
Transponders when the pulses are below the MTL. The inaccurate replies 
could result in reduced vertical separation or unsafe TCAS resolution 
advisories.

Is There Service Information That Applies To This Subject?

    GARMIN International Inc. has issued the Software Service Bulletin 
No.: 0304, Rev B, dated June 12, 2003.

What Are the Provisions of This Service Information?

    The service bulletin includes:

--Modification instructions for upgrading to software version 3.03 and
--A listing of parts required to perform the modification.

FAA's Determination and Requirements of This Proposed AD

What Has FAA Decided?

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. Therefore, we are proposing AD action.

What Would This Proposed AD Require?

    This proposed AD would require you to incorporate the actions in 
the previously-referenced service bulletin.

How Does the Revision to 14 CFR Part 39 Affect This Proposed AD?

    On July 10, 2002, we published a new version of 14 CFR part 39 (67 
FR 47997, July 22, 2002), which governs FAA's AD system. This 
regulation now includes material that relates to altered products, 
special flight permits, and alternative methods of compliance. This 
material previously was included in each individual AD. Since this 
material is included in 14 CFR part 39, we will not include it in 
future AD actions.

Costs of Compliance

How Many Airplanes Would This Proposed AD Impact?

    We estimate that this proposed AD affects 1300 airplanes in the 
U.S. registry.

What Would Be the Cost Impact of This Proposed AD on Owners/Operators 
of the Affected Airplanes?

    GARMIN International Inc. will cover all workhours and parts cost 
associated with this modification under warranty. The proposed AD would 
not impose any cost upon the owners/operators of any airplane that has 
the GTX 330/330D Software Upgrade to Version 3.03 installed.

Compliance Time of This Proposed AD

What Would Be the Compliance Time of This Proposed AD?

    The compliance time of this proposed AD is within 30 days after the 
effective date of the AD.

Why Is the Compliance Time Presented in Calendar Time Instead of Hours 
Time-In-Service (TIS)?

    The unsafe condition exists or could develop on airplanes equipped 
with the affected equipment regardless of airplane operation. For 
example, the unsafe condition has the same chance of occurring on an 
airplane with 50 hours TIS as it does on one with 5,000 hours TIS. 
Therefore, we are presenting the compliance time of the proposed AD in 
calendar time instead of hours TIS.

[[Page 75176]]

Regulatory Findings

Would This Proposed AD Impact Various Entities?

    We have 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.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

    For the reasons discussed above, I certify that this proposed AD:
    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); 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.
    We prepared a summary of the costs to comply with this proposed AD 
and placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-CE-39-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

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

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


Sec.  39.13  [Amended]

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

GARMIN International Inc.: Docket No. 2003-CE-39-AD

When Is the Last Date I Can Submit Comments on This Proposed AD?

    (a) We must receive comments on this proposed airworthiness 
directive (AD) by February 3, 2004.

What Other ADs Are Affected By This Action?

    (b) None.

What Products Are Affected by This AD?

    (c) This AD affects GARMIN International Inc. GTX 330/330D Mode 
S transponders that are installed on, but not limited to, the 
following airplanes, certificated in any category:

------------------------------------------------------------------------
              Manufacturer                            Model
------------------------------------------------------------------------
(1) Aermacchi S.p.A....................  S.205-18/F, S.205-18/R, S.205-
                                          20/R, S.205-22/R, S208,
                                          S.208A, F.260, F.260B, F.260C,
                                          F.260D, F.260E, F.260F,
                                          S.211A.
(2) Aeronautica Macchi S.p.A...........  AL 60, AL 60-B, AL 60-F5, AL 60-
                                          C5, AM-3.
(3) Aerostar Aircraft Corporation......  PA-60-600 (Aerostar 600), PA-60-
                                          601 (Aerostar 601), PA-60-601P
                                          (Aerostar 601P), PA-60-602P
                                          (Aerostar 602P), PA-60-700P
                                          (Aerostar 700P), 360, 400.
(4) Alexandria Aircraft, LLC...........  14-19, 14-19-2, 14-19-3, 14-19-
                                          3A, 17-30, 17-31, 17-31TC, 17-
                                          30A, 17-31A, 17-31ATC.
(5) Alliance Aircraft Group LLC........  15A, 20, H-250, H-295 (USAFU-
                                          10D), HT-295, H391 (USAFYL-
                                          24), H391B, H-395 (USAFL-28A
                                          or U-10B), H-395A, H-700, H-
                                          800, HST-550, HST-550A (USAF
                                          AU-24A), 500.
(6) American Champion Aircraft Corp....  402, 7GCA, 7GCB, 7KC, 7GCBA,
                                          7GCAA, 7GCBC, 7KCAB, 8KCAB,
                                          8GCBC.
(7) Sky International Inc..............  A-1, A-1A, A-1B, S-1S, S-1T, S-
                                          2, S-2A, S-2S, S-2C.
(8) B-N Group Ltd......................  BN-2, BN-2A, BN-2A-2, BN-2A-3,
                                          BN-2A-6, BN-2A-8, BN-2A-8, BN-
                                          2A-20, BN-2A-21, BN-2A-26, BN-
                                          2A-27, BN-2B-20, BN-2B-21, BN-
                                          2A-26, BN-2A-27, BN-2B-20, BN-
                                          2B-21, N-2B-26, BN-2B-27, BN-
                                          2T, BN-2T-4R, BN-2A MK.III,
                                          BN2A MK. III-2, BN2A MK. 111-
                                          3.
(9) Bellanca...........................  14-13, 14-13-2, 14-13-3, 14-13-
                                          3W.
(10) Bombardier Inc....................  (Otter) DHC-3, DHC-6-1, DHC-6-
                                          100, DHC-6-200, DHC-6-300.

[[Page 75177]]

 
(11) Cessna Aircraft...................  170, 170A, 170B, 172, 172A,
                                          172B, 172C, 172D, 172E, 172F
                                          (USAF T-41A), 172G, 172H (USAF
                                          T041A), 172I, 172K, 172L,
                                          172M, 172N, 172P, 172Q, 172R,
                                          172S, 172RG, P172D, R172E
                                          (USAF T-41 B) (USAF T-41 C AND
                                          D), R172F (USAF T-41 D),
                                          R175G, R172H (USAF T-41 D),
                                          R172J, R172K, 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,
                                          R182, T182, TR182, T182T, 185,
                                          185A, 185B, 185C, 185D, 185E,
                                          A185E, A185F, 190, (LC-126A,
                                          B, C) 195, 195A, 195B, 210,
                                          210A, 210B, 210C, 210D, 210E,
                                          210F, T210F, 210G, T210G,
                                          210H, T210H, 210J, T210J,
                                          210K, T210K, 210L, T210L,
                                          210M, T210M, 210N, P210N,
                                          T210N, 210R, P210R, T210R, 210-
                                          5 (205), 210-5A (205A), 206,
                                          P206, P206A, P206B, P206C,
                                          P206D, P206E, TP206A, TP206B,
                                          TP206C, TU206D, TU206E,
                                          TU206F, TU206G, 206H, T206H,
                                          207, 207A, T207, T207A, 208,
                                          208A, 208B, 310, 310A (USAF U-
                                          3A), 310B, 310C, 310D, 310E
                                          (USAF U-3B), 310F, 310G, 310H,
                                          E310H, 310I, 310J, 310J-1,
                                          E310J, 310K, 310L, 310N, 310P,
                                          T310P, 310Q, T310Q, 310R,
                                          T310R, 320, 320A, 320B, 320C,
                                          320D, 320E, 320F, 320-1, 335,
                                          340, 340A, 336, 337, 337A
                                          (USAF 02B), 337B, T337B, 337C,
                                          337E, T337E, T337C, 337D,
                                          T337D, M337B (USAF 02A), 337F,
                                          T337F, T337G, 337G, 337H,
                                          P337H, T337H, T337H-SP, 401,
                                          401A, 401B, 402, 402A, 402B,
                                          402C, 411, 411A, 414, 414A,
                                          421, 421A, 421B, 421C, 425,
                                          404, 406, 441.
(12) Cirrus Design Corporation.........  SR20, SR22.
(13) Commander Aircraft Company........  112, 112TC, 112B, 112TCA, 114,
                                          114A, 114B, 114TC.
(14) de Havilland Inc..................  DHC-2 Mk. I, DHC-2 Mk.II, DHC-2
                                          Mk. III.
(15) Dynac Aerospace Corporation.......  (Volaire) 10, (Volaire) 10A,
                                          (Aero Commander) 100, (Aero
                                          Commander) 100A, (Aero
                                          Commander) 100-180.
(16) Diamond Aircraft Industries.......  DA-20 A1, DA20-C1, DA 40.
(17) Empressa Brasileira de Aeronautica  EMB-110P1, EMB-110P2.
 S.A. EMBRAER.
(18) Extra Flugzeugbau Gmbh............  A300, EA300L, EA300S, EA300/
                                          200, EA-400.
(19) Fairchild Aircraft Corporation....  SA26-T, SA26-AT, SA226-T, SA226-
                                          AT, SA226-T(B), SA227-AT,
                                          SA227-TT, SA226-TC, SA227-AC
                                          (C-26A), SA227-CC, SA227-DC (C-
                                          26B).
(20) Global Amphibians, LLC............  Colonial C-1, Colonial C-2,
                                          Lake LA-4, Lake LA-4A, Lake LA-
                                          4P, Lake LA-4-200, Lake Model
                                          250.
(21) Grob-Werke........................  G115, G115A, G115B, G115C,
                                          G115C2, G115D, G115D2, G115EG,
                                          G120A.
(22) Lancair Company...................  LC40-550FG.
(23) LanShe Aerospace, LLC.............  MAC-125C, MAC-145, MAC-145A,
                                          MAC-145B.
(24) Learjet Inc.......................  23.
(25) Lockheed Aircraft Corporation.....  18.
(26) Luscombe Aircraft Corporation.....  11A, 11E.
(27) Maule Aerospace Technology, Inc...  Bee Dee M-4, M-4, M-4C, M-4S, M-
                                          4T, M-4180C, M-4-180S, M-4-
                                          180T, M-4-210, M-4-210C, M-4-
                                          210S, M-4-210T, M-4-220, M-4-
                                          220S, M-4-220T, 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, MX-7-235, MX-7-
                                          180, MX-7-420, MXT-7-180, MT-7-
                                          235, M-8-235, MX-7-160, MXT-7-
                                          160, MX-7-180A, MXT-7-180A, MX-
                                          7-180B, M-7-235B, M-7-235A, M-
                                          7-235C, MX-7-180C, M-7-260, MT-
                                          7-260, M-7-260C, M-7-420AC, MX-
                                          7-160C, MX-7-180AC, M-7-420A,
                                          MT-7-420.
(28) Mitsubishi Heavy Industries, Ltd..  MU-2B-25, MU-2B-35, MU-2B-26,
                                          MU-2B-36, MU-2B-26A, MU-2B-
                                          36A, MU-2B-40, MU-2B-60, MU-
                                          2B, MU-2B-20, MU-2B-20, MU-2B-
                                          15.
(29) Mooney Airplane Company, Inc......  M20, M20A, M20B, M20C, M20D,
                                          M20E, M20F, M20G, M20J, M20K,
                                          M20L, M20M, M20R, M20S, M22.
(30) Moravan a.s.......................  Z-242L, Z-143L.
(31) Navion Aircraft Company, Ltd......  NAVION, Navion (L-17A), Navion
                                          (L17B), Navion (L-17C), Navion
                                          B, Navion D, Navion E, Navion
                                          F, Navion G, Navion H.

[[Page 75178]]

 
(32) New Piper Aircraft, Inc...........  PA-12, PA-12S, PA-18, PA-18S,
                                          PA-18 ``105'' (Special), PA-
                                          18S ``105'' (Special), PA-18A,
                                          PA-18 ``125'' (Army L-21A), PA-
                                          18S ``125,'' PA-18AS ``125','
                                          PA-18 ``135'' (Army L-21B), PA-
                                          18A ``135,'' PA-18S ``135,''
                                          PA-18 ``150,'' PA-18A ``150,''
                                          PA-18S ``150,'' PA-18AS
                                          ``150,'' PA-19 (Army L-18B),
                                          PA-19S, PA-20, PA-20S, PA-20
                                          ``115,'' PA-20S ``115,'' PA-
                                          20, ``135,'' PA-20S ``135,''
                                          PA-22, PA-22-108, PA-22-135,
                                          PA-22S-135, PA-22-150, PA-22S-
                                          150, PA-22-160, PA-22S-160, PA-
                                          23, PA-23-160, PA-23-235, PA-
                                          23-250, PA-E23-250, 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-28-235, PA-28S-160,
                                          PA-28R-180, PA-28S-180, PA-28-
                                          181, PA-28R-200, PA-28R-201,
                                          PA-28R-201T, PA-28RT-201, PA-
                                          28RT-201T, PA-28-201T, PA-28-
                                          236, PA-30, PA-39, PA-40, PA-
                                          31P, PA-31T, PA-31T1, PA-31T2,
                                          PA-31T3, PA-31P-350, PA-32-
                                          260, PA-32-300, PA-32S-300, PA-
                                          32R-300, PA-32RT-300, PA-32RT-
                                          300T, PA-32R-301 (SP), PA-32R-
                                          301 (HP), PA-32R-301T, PA-32-
                                          301, PA-32-301T, PA-34-200, PA-
                                          34-200T, PA-34-220T, PA-42, PA-
                                          42-720, PA-42-1000, PA-42-
                                          720R, PA-44-180, PA-44-180T,
                                          PA-46-310P, PA-46-350P, PA-46-
                                          500TP
(33) Ostmecklenburgische Flugzeugbau     OMF-100-160.
 GmgH.
(34) Piaggio Aero Industries S.p.A.....  P-180.
(35) Pilatus Aircraft Ltd..............  PILATUS PC-12, PILATUS PC-12/
                                          45, PC-6, PC-6-H1, PC-6-H2, PC-
                                          6/350, PC-6/350-H1, PC-6/350-
                                          H2, PC-6/A, PC-6/A-H1, PA-6/A-
                                          H2, PC-6/B-H2, PC-6/B1-H2, PC-
                                          6/B2-H2, PC-6/B2-H4, PC-6/C-
                                          H2, PC-6/C1-H2, PC-7.
(36) Prop-Jets, Inc....................  200, 200A, 200B, 200C, 200D,
                                          400.
(37) Panstwowe Zakladv Lotnicze (PZL)..  PZL-104 WILGA 80, PZL-104M
                                          WILGA 2000, PZL-WARSZAWA, PZL-
                                          KOLIBER 150A, PZL-KOLIBER
                                          160A.
(38) PZL WSK/Mielec Obrsk..............  PZL M20 03, PZL M26 01.
(39) Raytheon..........................  35-33, 35-A33, 35-B33, 35-C33,
                                          35-C33A, E33, E33A, E33C, F33,
                                          F33A, F33C, G33, H35, J35,
                                          K35, M35, N35, P35, S35, V35,
                                          V35A, V35B, 36, A36, A36TC,
                                          B36TC, 35, A35, B35, C35, D35,
                                          E35, F35, G35, 35R, F90, 76,
                                          200, 200C, 200CT, 200T, A200,
                                          B200, B200C, B200CT, B200T,
                                          300, 300LW, B300, B300C, 1900,
                                          1900C, 1900D, A100-1 (U-21J),
                                          A200 (C-12A), A200 (C-12C),
                                          A200C (UC-12B), A200CT (C-
                                          12D), A200CT (FWC-12D), A200CT
                                          (RC-12D), A200CT (C-12F),
                                          A200CT (RC-12G), A200CT (RC-
                                          12H), A200CT (RC-12K), A200CT
                                          (RC-12P), A200CT (RC-12Q),
                                          B200C (C-12F), B200C (UC-12F),
                                          B200C (UC-12M), B200C (C-12R),
                                          1900C (C-12J), 65, A65, A65-
                                          8200, 65-80, 65-A80, 65A80-
                                          8800, 65-B80, 65-88, 65-A90,
                                          70, B90, C90, C90A, E90, H90,
                                          65-A90-1, 65-A90-2, 65-A90-3,
                                          65-A90-4, 95, B95, B95A, D95A,
                                          E95, 95-55, 95-A55, 95-B55, 95-
                                          B55A, 95-B55B (T-42A), 95-C55,
                                          95-C55A, D55, D55A, E55, E55A,
                                          56TC, A56TC, 58, 58A, 58P,
                                          58PA, 58TC, 58TCA, 99, 99A,
                                          99A (FACH), A99, A99A, B99,
                                          C99, 100, A100 (U-21F), A100A,
                                          A100C, B100, 2000, 3000, 390,
                                          19A, B19, M19A, 23, A23, A23A,
                                          A23-19, A23-24, B23, C23, A24,
                                          A24R, B24R, C24R, 60, A60,
                                          B60, 18D, A18A, A18D, S18D,
                                          SA18A, SA18D, 3N, 3NM, 3TM,
                                          JRB-6, D18C, D18S, E18S, RC-
                                          45J (SNB-5P), E18S-9700, G18S,
                                          H18, C-45G, TC-45G, C-45H, TC-
                                          45H, TC-45J, UC-45J (SNB-5),
                                          50 (L-23A), B50 (L-23B), C50,
                                          D50 (L-23E), D50A, D50B, D50C,
                                          D50E-5990, E50 (L-23D, RL-
                                          23D), F50, G50, H50, J50, 45
                                          (YT-34), A45 (T-34A or B-45),
                                          D45 (T-34B).
(40) Rockwell International Corporation  BC-1A, AT-6 (SNJ-2), AT-6A (SNJ-
                                          3), AT-6B, AT-6C (SNJ-4), AT-
                                          6D (SNJ-5), AT-6F (SNF-6), SNJ-
                                          7, T-6G, NOMAD NA-260.
(41) Short Brothers & Harland Ltd......  SC-7 Series 2, SC-7 Series 3.
(42) Slingsby Aviation Ltd.............  T67M260, T67M260-T3A.
(43) SOCATA--Group Aerospatiale........  TB9, TB10, TB20, TB21, TB200,
                                          TBM 700, M.S. 760, M.S. 760 A,
                                          M.S. 760 B, Rallye 100S,
                                          Rallye 150ST, Rallye 150T,
                                          Rallye 235E, Rallye 235C, MS
                                          880B, MS 885, MS 894A, MS
                                          893A, MS 892A-150, MS 892E-
                                          150, MS 893E, MS 894E, GA-7.
(44) Tiger Aircraft LLC................  AA-1, AA-1A, AA-1B, AA-1C, AA-
                                          5, AA-5A, AA-5B, AG-5B.
(45) Twin Commander Aircraft             500, 500-A, 500-B, 500-U, 500-
 Corporation.                             S, 520, 560, 560-A, 560-E,
                                          560F, 680, 680E, 680F, 680FL,
                                          680FL(P), 680T, 680V, 680W,
                                          681, 685, 690, 690A, 690B,
                                          690C, 690D, 695, 695A, 695B,
                                          720, 700.
(46) Univair Aircraft Corporation......  108, 108-1, 108-2, 108-3, 108-
                                          5.
(47) Vulcanair S.p.A...................  P68, P68B, P68C, P68C-TC, P68
                                          ``Observer,'' P68 ``Observer
                                          2,'' P68TC ``Observer,''
                                          AP68TP300 ``Spartacus,''
                                          AP68TP 600 ``Viator.''
(48) Zenair Ltd........................  CH2000.
------------------------------------------------------------------------


[[Page 75179]]

What Is the Unsafe Condition Presented in This AD?

    (d) The actions specified in this AD are intended to prevent 
interrogating aircraft from possibly receiving inaccurate replies, 
due to suppression, from aircraft equipped with the GTX 330/330D 
Mode S Transponders when the pulses are below the Minimum Trigger 
Level (MTL). The inaccurate replies could result in reduced vertical 
separation or unsafe TCAS resolution advisories.

What Must I Do To Address This Problem?

    (e) To address this problem, you must accomplish the following:

------------------------------------------------------------------------
           Action                  Compliance            Procedures
------------------------------------------------------------------------
Install GTX 330/330D          Install the software  Follow GARMIN
 software upgrade to version   upgrade within 30     International Inc.
 3.03.                         days after the        Service Bulletin
                               effective date of     No.: 0304, Rev B,
                               this AD, unless       dated June 12,
                               already               2003.
                               accomplished.
------------------------------------------------------------------------

How Do I Get Copies of the Documents Referenced in This AD?

    (g) You may get copies of the documents referenced in this AD 
from GARMIN International Inc. 1200 East 151st Street, Olathe, KS 
66062. You may view these documents at FAA, Central Region, Office 
of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 
64106.

    Issued in Kansas City, Missouri, on December 19, 2003.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 03-31978 Filed 12-29-03; 8:45 am]
BILLING CODE 4910-13-P