(a) EFFECTIVE DATE

    This AD is effective January 21, 2014.

(b) AFFECTED ADS

    This AD revises AD 98-15-18, Amendment 39-10669 (63 FR 39018, July 21,
    1998), which  superseded AD  95-26-18, Amendment  39-9476 (61  FR 623,
    January 9, 1996.)

(c) APPLICABILITY

    This  AD applies  to the  following Maule  Aerospace Technology,  Inc.
    airplanes, all serial numbers, identified in figure 1 of paragraph (c)
    of this AD, that are:

(1) Equipped  with  original  equipment manufacturer (OEM) Maule Aerospace
    Technology, Inc. rear  wing lift struts,  part number (P/N)  2079E (or
    FAA-approved equivalent part numbers), and/or front wing lift  struts,
    P/N  2080E  (or  FAA-approved  equivalent  part  numbers),   excluding
    airplanes equipped with four Maule  sealed lift struts, P/N 2200E  and
    P/N 2201E, which are identified by two raised weld spots on the  upper
    end of the strut  just below the serial  number plate. Removal of  the
    upper cuff is needed to locate the weld spots; and

(2) certificated in any category.

           FIGURE 1 TO PARAGRAPH (C) OF THIS AD - APPLICABILITY           
__________________________________________________________________________
                                 MODELS
__________________________________________________________________________
Bee Dee M-4      M-4            M-4C            M-4S             M-4T
M-4-180C         M-4-180S       M-4-180T        M-4-210          M-4-210C
M-4-210S         M-4-210T       M-4-220         M-4-220C         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
M-7-235A         M-7-235B       M-7-235C        MT-7-235         MX-7-160
MX-7-180         MX-7-180A      MX-7-180B       MX-7-235         MX-7-420
MXT-7-160        MXT-7-180      MXT-7-180A      M-8-235
_________________________________________________________________________

(d) SUBJECT

    Joint Aircraft System Component (JASC)/Air Transport Association (ATA)
    of America Code 57, Wings.

(e) UNSAFE CONDITION

(1) The subject of this AD was originally prompted by reports of corrosion
    damage found  on the  wing lift  struts. We  are revising AD 98-15-18,
    Amendment 39-10669 (63  FR 39018, July 21, 1998),  because  of reports
    that the language in paragraph (b) had been misinterpreted and  caused
    confusion.  Since  we issued  AD  98-15-18, we  were  informed by  the
    manufacturer  that  Model  MXT-7-420   airplanes  are  no  longer   in
    existence, are no longer type certificated, and should be removed from
    the Applicability section. This  AD removes Model MXT-7-420  airplanes
    from  the  Applicability  section  and  clarifies  the  intent  of the
    language in paragraph  (b) of AD  98-15-18, which is  being removed by
    this AD.

(2) This AD clarifies the FAA's intention that if a sealed wing lift strut
    assembly is installed as a replacement part, the repetitive inspection
    requirement is terminated only if the seal is never improperly broken.
    If the seal  is improperly broken,  then that wing  lift strut becomes
    subject  to continued  repetitive inspections.  We did  not intend  to
    promote drilling  holes into  or otherwise  unsealing a  sealed strut.
    This AD retains all the actions  required in AD 98-15-18 and does  not
    add any  actions over  that already  required in  AD 98-15-18. This AD
    does not  add any  additional burden  to the  owners/operators of  the
    affected airplanes.

(3) We are issuing this AD  to  detect and correct corrosion  on the front
    and rear wing lift  struts, which could cause  the wing lift strut  to
    fail.  This  failure could  result  in the  wing  separating from  the
    airplane.

(f) PARAGRAPH DESIGNATION CHANGES TO AD 98-15-18

    Since AD 98-15-18,  Amendment 39-10669 (63  FR 39018,  July 21, 1998),
    was issued,  the AD  format has  been revised,  and certain paragraphs
    have  been  rearranged.  As  a  result,  the  corresponding  paragraph
    identifiers have changed in this AD, as listed in the following table:

      TABLE 1 TO PARAGRAPH (F) OF THIS AD - REVISED PARAGRAPH IDENTIFIERS 
    ______________________________________________________________________
                                         CORRESPONDING REQUIREMENT
         REQUIREMENT IN AD 98-15-18              IN THIS AD
    ______________________________________________________________________
                   paragraph (a)                 paragraph (h)
                paragraph (a)(1)              paragraph (i)(1)
             paragraph (a)(1)(i)           paragraph (i)(1)(i)
            paragraph (a)(1)(ii)          paragraph (i)(1)(ii)
                paragraph (a)(2)              paragraph (i)(2)
             paragraph (a)(2)(i)           paragraph (i)(2)(i)
            paragraph (a)(2)(ii)          paragraph (i)(2)(ii)
                paragraph (a)(3)              paragraph (j)(1)
        paragraph (a)(4) and (c)              paragraph (j)(2)
                   paragraph (b)                       Removed
    ______________________________________________________________________

(g) COMPLIANCE

    Unless already done (compliance  with AD 98-15-18, Amendment  39-10669
    (63 FR  39018, July  21, 1998)),  do the  following actions within the
    compliance times specified in paragraphs  (h) through (j) of this  AD,
    including all subparagraphs. Properly unsealing and resealing a sealed
    wing  lift strut  is still  considered  a  terminating action  for the
    repetitive  inspection  requirements  of  this  AD  as  long  as   all
    appropriate  regulations and  issues are  considered,  such  as static
    strength, fatigue, material effects, immediate and long-term (internal
    and external)  corrosion protection,  resealing methods,  etc. Current
    FAA regulations in 14 CFR 43.13(b) specify that maintenance  performed
    will  result in  the part's  condition  to  be at  least equal  to its
    original or properly altered  condition. Any maintenance actions  that
    unseal a sealed wing lift strut should be coordinated with the Atlanta
    Aircraft Certification  Office (ACO)  through the  local airworthiness
    authority  (e.g.,  Flight   Standards  District  Office).   There  are
    provisions in paragraph (k) of  this AD for approving such  actions as
    an alternative method of compliance (AMOC).

(h) REMOVE WING LIFT STRUTS

    At whichever of the  compliance times specified in  paragraphs (h)(1),
    (h)(2), or (h)(3) of this AD  that occurs later, remove the wing  lift
    struts following the INSTRUCTIONS section  in PART I of Maule  Service
    Bulletin (SB) No.  11, dated October  30, 1995. Before  further flight
    after the removal, do the  actions in one of the  following paragraphs
    (i)(1),  (i)(2),  (j)(1),  or   (j)(2)  of  this  AD,   including  all
    subparagraphs.

(1) Upon accumulating 2 years time-in-service  on  an  OEM Maule wing lift
    strut, P/N 2079E and/or P/N 2080E;

(2) Within 3 calendar months  after  September 9, 1998 (the effective date
    retained from  AD 98-15-18,  Amendment 39-10669 (63 FR 39018, July 21,
    1998)); or

(3) Within 2 years  after  the  last inspection done in accordance with AD
    95-26-18,  Amendment 39-9476  (61 FR 623,  January 9, 1996) (which was
    superseded by AD 98-15-18).

(i) INSPECT WING LIFT STRUTS

    Before further flight after the  removal required in paragraph (h)  of
    this AD, inspect  each wing lift  strut following paragraph  (i)(1) or
    (i)(2) of this  AD, including all  subparagraphs, or do  the wing lift
    strut replacement following one of the options in paragraph (j)(1)  or
    (j)(2) of this AD.

(1) Inspect  each  wing  lift  strut  for  corrosion and perceptible dents
    following the INSTRUCTIONS section in PART I of Maule SB No. 11, dated
    October 30, 1995.

(i) If no corrosion is visible  and  no perceptible dents are found on any
    wing lift strut during the inspection required in paragraph (i)(1)  of
    this AD, before further flight, apply corrosion inhibitor to each wing
    lift strut following  the INSTRUCTIONS section  in PART I  of Maule SB
    No. 11, dated October  30, 1995. Repetitively thereafter  inspect each
    wing  lift  strut  at  intervals  not  to  exceed  24  calendar months
    following the  procedures in  paragraph (i)(1)  or (i)(2)  of this AD,
    including all subparagraphs.

(ii) If corrosion or  perceptible  dents  are found on any wing lift strut
     during the  inspection required  in paragraph  (i)(1) of  this AD  or
     during any repetitive inspection  required in paragraph (i)(1)(i)  of
     this AD, before further flight, replace the affected wing lift  strut
     with one of the replacement options specified in paragraph (j)(1)  or
     (j)(2)  of  this  AD. Do  the  replacement  following the  procedures
     specified in those paragraphs, as applicable.

(2) Inspect each wing lift strut for corrosion following the procedures in
    the Appendix to this AD. This inspection must be done by a Level 2  or
    Level 3 inspector  certified using the  guidelines established by  the
    American Society for Non-destructive Testing or the "Military Standard
    for Nondestructive Testing Personnel Qualification and  Certification"
    (MIL-STD-410E), which can be found on the Internet at http://aerospace
    defense.thomasnet.com/Asset/ MIL-STD-410.pdf.

(i) If no corrosion is found on any wing lift strut  during the inspection
    required in paragraph  (i)(2) of this  AD and all  requirements in the
    Appendix to this  AD are met,  before further flight,  apply corrosion
    inhibitor to each wing  lift strut following the  INSTRUCTIONS section
    in PART I  of Maule SB  No. 11, dated  October 30, 1995.  Repetitively
    thereafter inspect each wing lift strut at intervals not to exceed  24
    calendar months following the procedures in paragraph (i)(1) or (i)(2)
    of this AD, including all subparagraphs.

(ii) If  corrosion  is  found on any wing lift strut during the inspection
     required in  paragraph (i)(2)  of this  AD or  during any  repetitive
     inspection required  in paragraph  (i)(2)(i) of  this AD,  or if  any
     requirement in  the Appendix  of this  AD is  not met, before further
     flight  after  any inspection  in  which corrosion  is  found or  the
     Appendix requirements  are not  met, replace  the affected  wing lift
     strut  with one  of the  replacement options  specified in  paragraph
     (j)(1)  or  (j)(2)  of  this AD.  Do  the  replacement  following the
     procedures specified in those paragraphs, as applicable.

(j) WING LIFT STRUT REPLACEMENT OPTIONS

    Before further flight after the  removal required in paragraph (h)  of
    this AD, replace the wing lift struts following one of the options  in
    paragraph (j)(1) or (j)(2) of this AD, or inspect each wing lift strut
    following  paragraph  (i)(1)  or  (i)(2)  of  this  AD,  including all
    subparagraphs.

(1) Install OEM Maule  P/N  wing  lift  struts (or FAA-approved equivalent
    part numbers)  that have  been inspected  following the  procedures in
    either  paragraph  (i)(1)  or   (i)(2)  of  this  AD,   including  all
    subparagraphs, and  are found  to be  airworthy. Do  the installations
    following the  INSTRUCTIONS section  in PART  II of  Maule SB  No. 11,
    dated  October 30, 1995.  Repetitively  thereafter inspect  the  newly
    installed wing  lift struts  at intervals  not to  exceed 24  calendar
    months following the procedures  in either paragraph (i)(1)  or (i)(2)
    of this AD, including all subparagraphs.

(2) Install new Maule sealed wing lift struts,  P/N 2200E or P/N 2201E, as
    applicable  (or FAA-approved  equivalent part  numbers) following  the
    INSTRUCTIONS section in PART II of Maule SB No. 11,  dated October 30,
    1995. Installing one  of these new  sealed wing lift  strut assemblies
    terminates the repetitive inspection requirements in paragraphs (i)(1)
    or (i)(2) of this AD, including all subparagraphs, for that wing  lift
    strut assembly.

(k) ALTERNATIVE METHODS OF COMPLIANCE (AMOCS)

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

(3) AMOCs approved for AD 98-15-18,  Amendment 39-10669 (63 FR 39018, July
    21, 1998) and  AD 95-26-18,  Amendment  39-9476 (61 FR 623, January 9,
    1996) are approved as AMOCs for this AD.

(l) RELATED INFORMATION

    For  more  information  about  this  AD,  contact  Gregory  K.  Noles,
    Aerospace Engineer,  FAA, Atlanta  ACO, 1701  Columbia Avenue, College
    Park, Georgia 30337; phone: (404) 474-5551; fax: (404) 474-5606; email
    gregory.noles@faa.gov.

(m) MATERIAL INCORPORATED BY REFERENCE

(1) The  Director  of  the  Federal Register approved the incorporation by
    reference (IBR) 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.

(3) The following  service information was approved for IBR on January 26,
    1996 (61 FR 623, January 9, 1996).

(i) Maule Service Bulletin No. 11, dated October 30, 1995.

(ii) Reserved.

(4) For Maule Aerospace Technology, Inc. service information identified in
    this AD,  contact Maule  Air, Inc.,  2099 GA  Hwy 133 South, Moultrie,
    Georgia  31768;  telephone:  (229)  985-2045;  fax:  (229)   890-2402;
    Internet: http://www.mauleairinc.com/pdf/servicebulletins/service_bull
    etin_11_old.pdf.

(5) You may view this service information  at  Small Airplane Directorate,
    901  Locust,  Kansas  City, Missouri  64106.  For  information on  the
    availability of this material at the FAA, call (816) 329-4148.

(6) You  may  view  this  service  information  that  is  incorporated  by
    reference at the National Archives and Records Administration  (NARA).
    For information  on the  availability of  this material  at NARA, call
    202-741-6030,  or go to: http://www.archives.gov/federal-register/cfr/
    ibr-locations.html.

APPENDIX TO AD 98-15-18 R1

PROCEDURES AND REQUIREMENTS FOR  ULTRASONIC INSPECTION OF MAULE  WING LIFT
STRUTS

EQUIPMENT REQUIREMENTS

1. A portable ultrasonic thickness gauge  or  flaw detector  with echo-to-
   echo digital thickness readout capable of reading to 0.001-inch and  an
   A-trace waveform display will be needed to do this inspection.

2. An ultrasonic probe with the following specifications will be needed to
   do  this  inspection:  10  MHz  (or  higher),  0.283-inch  (or smaller)
   diameter dual element or  delay line transducer designed  for thickness
   gauging.  The  transducer and  ultrasonic  system shall  be  capable of
   accurately measuring  the thickness  of AISI  4340 steel  down to 0.020
   -inch. An accuracy of  0.002-inch throughout a 0.020-inch to 0.050-inch
   thickness range while calibrating shall be the criteria for acceptance.

3. Either  a  precision machined step wedge made of 4340 steel (or similar
   steel with equivalent sound velocity) or at least three shim samples of
   same material will  be needed to  do this inspection.  One thickness of
   the step wedge or shim shall  be less than or equal to  0.020-inch, one
   shall be greater  than or equal  to 0.050-inch and  at least one  other
   step or shim shall be between these two values.

4. Glycerin,  light oil,  or  similar non-water based ultrasonic couplants
   are recommended  in the  setup and  inspection procedures.  Water-based
   couplants,  containing   appropriate  corrosion   inhibitors,  may   be
   utilized, provided they are  removed from both the  reference standards
   and  the  test  item after  the inspection  procedure is  completed and
   adequate corrosion  prevention steps  are then  taken to  protect these
   items.

NOTE: Couplant is  defined as "a  substance used between  the face of  the
transducer and test surface  to improve transmission of  ultrasonic energy
across the transducer/strut interface."

NOTE: If surface roughness due to paint loss or corrosion is present,  the
surface should  be sanded  or polished  smooth before  testing to assure a
consistent and smooth surface for making contact with the transducer. Care
shall be taken  to remove a  minimal amount of  structural material. Paint
repairs may be necessary after the inspection to prevent further corrosion
damage from occurring. Removal of surface irregularities will enhance  the
accuracy of the inspection technique.

INSTRUMENT SETUP

1. Set up the ultrasonic equipment for thickness measurements as specified
   in the instrument's user's manual. Because of the variety of  equipment
   available   to   perform   ultrasonic   thickness   measurements,  some
   modification to this general setup procedure may be necessary. However,
   the tolerance requirement of step 13 and the record keeping requirement
   of step 14, must be satisfied.

2. If  battery power will be employed,  check  to see that the battery has
   been properly charged. The  testing will take approximately  two hours.
   Screen brightness  and contrast  should be  set to  match environmental
   conditions.

3. Verify  that  the  instrument  is  set for the type of transducer being
   used, i.e. single  or dual element,  and that the  frequency setting is
   compatible with the transducer.

4. If a removable delay line is used,  remove it and place a drop of coup-
   lant between  the transducer  face and  the delay  line to  assure good
   transmission of ultrasonic energy. Reassemble the delay line transducer
   and continue.

5. Program  a  velocity of 0.231-inch/microsecond into the ultrasonic unit
   unless an alternative instrument  calibration procedure is used  to set
   the sound velocity.

6. Obtain a step wedge or steel shims per item 3 of the Equipment Require-
   ments. Place the  probe on the  thickest sample using  couplant. Rotate
   the transducer slightly back and forth to "ring" the transducer to  the
   sample. Adjust  the delay  and range  settings to  arrive at an A-trace
   signal display  with the  first backwall  echo from  the steel near the
   left side of the screen and the second backwall echo near the right  of
   the screen.  Note that  when a  single element  transducer is used, the
   initial pulse  and the  delay line/steel  interface will  be off of the
   screen to the left. Adjust the gain to place the amplitude of the first
   backwall signal at approximately 80% screen height on the A-trace.

7. "Ring"  the  transducer  on  the  thinnest step or shim using couplant.
   Select positive half-wave  rectified, negative half-wave  rectified, or
   filtered signal display to obtain the cleanest signal. Adjust the pulse
   voltage, pulse width, and damping to obtain the best signal resolution.
   These settings  can vary  from one  transducer to  another and are also
   user dependent.

8. Enable the thickness gate, and adjust the gate so that it starts at the
   first backwall echo  and ends at  the second backwall  echo. (Measuring
   between the first and second backwall echoes will produce a measurement
   of the steel thickness that is  not affected by the paint layer  on the
   strut). If  instability of  the gate  trigger occurs,  adjust the gain,
   gate level, and/or damping to stabilize the thickness reading.

9. Check the digital  display  reading  and  if it does not agree with the
   known thickness  of the  thinnest thickness,  follow your  instrument's
   calibration recommendations to  produce the correct  thickness reading.
   When a  single element  transducer is  used this  will usually  involve
   adjusting the fine delay setting.

10. Place the  transducer on the thickest step of shim using couplant. Ad-
    just the thickness  gate width so  that the gate  is triggered by  the
    second  backwall  reflection  of the  thick  section.  If the  digital
    display  does  not  agree with  the  thickest  thickness, follow  your
    instruments  calibration  recommendations   to  produce  the   correct
    thickness  reading.  A  slight  adjustment  in  the  velocity  may  be
    necessary to get both the  thinnest and the thickest reading  correct.
    Document the changed velocity value.

11. Place couplant on an  area  of  the  lift strut which is thought to be
    free  of  corrosion  and  "ring"  the  transducer  to  surface.  Minor
    adjustments to the signal and gate settings may be required to account
    for  coupling  improvements  resulting  from  the  paint  layer.   The
    thickness gate level should  be set just high  enough so as not  to be
    triggered by irrelevant signal noise. An area on the upper surface  of
    the lift strut above the inspection  area would be a good location  to
    complete  this step  and should  produce a  thickness reading  between
    0.034-inch and 0.041-inch.

12. Repeat steps 8, 9, 10,  and 11 until both thick and thin shim measure-
    ments  are  within  tolerance  and  the  lift  strut  measurement   is
    reasonable and steady.

13. Verify that the thickness value shown in the digital display is within
    0.002-inch of the correct value for each of the three or more steps of
    the  setup  wedge  or  shims.  Make  no  further  adjustments  to  the
    instrument settings.

14. Record the  ultrasonic  versus  actual thickness of all wedge steps or
    steel shims available as a record of setup.

INSPECTION PROCEDURE

1. Clean the lower 18 inches of the wing lift struts  using a cleaner that
   will remove all dirt and grease. Dirt and grease will adversely  affect
   the accuracy of  the inspection technique.  Light sanding or  polishing
   may  also be  required  to  reduce surface  roughness as  noted in  the
   Equipment Requirements section.

2. Using a flexible ruler, draw a 1/4-inch grid  on  the  surface  of  the
   first 11 inches from the lower end of the strut as shown in Maule  Air,
   Inc. Service Bulletin  No. 11, dated  October 30, 1995,  as applicable.
   This can be  done using a  soft (2) pencil  and should be  done on both
   faces of the strut. As an alternative to drawing a complete grid,  make
   two rows of marks spaced every 1/4 inch across the width of the  strut.
   One row of marks  should be about 11  inches from the lower  end of the
   strut, and the second row should be several inches away where the strut
   starts to narrow. Lay the flexible ruler between respective tick  marks
   of the two  rows and use  tape or a  rubber band to  keep the ruler  in
   place. See Figure 1.

3. Apply a generous amount of  couplant inside each of the square areas or
   along  the  edge  of  the  ruler.  Re-application  of  couplant  may be
   necessary.

4. Place the transducer inside  the first square area of the drawn grid or
   at the first 1/4-inch  mark on the ruler  and "ring" the transducer  to
   the strut.  When using  a dual  element transducer,  be very careful to
   record the  thickness value  with the  axis of  the transducer elements
   perpendicular to any curvature in the strut. If this is not done,  loss
   of signal or inaccurate readings can result.

5. Take readings inside each square on the grid or  at 1/4-inch increments
   along  the  ruler  and  record the  results.  When  taking  a thickness
   reading, rotate the transducer  slightly back and forth  and experiment
   with  the angle  of contact  to  produce  the lowest  thickness reading
   possible. Pay close attention to the A-scan display to assure that  the
   thickness gate is triggering off of maximized backwall echoes.

NOTE: A  reading shall  not exceed  .041 inch.  If a  reading exceeds .041
inch,  repeat  steps  13 and  14 of  the Instrument  Setup section  before
proceeding further.

6. If the A-trace is unsteady  or  the thickness reading is clearly wrong,
   adjust the  signal gain  and/or gate  setting to  obtain reasonable and
   steady readings. If any instrument setting is adjusted, repeat steps 13
   and 14 of the Instrument Setup section before proceeding further.

7. In areas where obstructions are present,  take a data point as close to
   the correct area as possible.

NOTE: The strut wall contains  a fabrication bead at approximately  40% of
the strut chord. The bead may interfere with accurate measurements in that
specific location.

8. A measurement of  0.024 inch  or  less shall require replacement of the
   strut prior to further flight.

9. If at  any  time  during  testing  an area is encountered where a valid
   thickness  measurement  cannot be  obtained  due to  a  loss of  signal
   strength or quality, the area shall be considered suspect. These  areas
   may have a remaining wall  thickness of less than 0.020-inch,  which is
   below  the  range  of this  setup,  or  they may  have  small  areas of
   localized corrosion or pitting present. The latter case will result  in
   a reduction in  signal strength due  to the sound  being scattered from
   the rough surface and may result in a signal that includes echoes  from
   the pits as well as the  backwall. The suspect area(s) shall be  tested
   with a Maule  "Fabric Tester" as  specified in Maule  Air, Inc. Service
   Bulletin No. 11, dated October 30, 1995.

10. Record the lift strut inspection in the aircraft log book.

                        ILLUSTRATION (Figure 1)

Issued in  Kansas City,  Missouri,  on  November 22, 2013. Earl  Lawrence,
Manager, Small Airplane Directorate, Aircraft Certification Service.

FOR  FURTHER  INFORMATION   CONTACT:  Gregory  "Keith"   Noles,  Aerospace
Engineer,  FAA,  Atlanta  Aircraft  Certification  Office,  1701  Columbia
Avenue, College Park, Georgia 30337;  phone:  (404) 474-5551;  fax:  (404)
474-5606; email: gregory.noles@faa.gov.