TM 1-1510-218-10 3A-47/(3A-48 blank) 4.   VA FAIL annunciator light – Extinguished. 5.   Radio altimeter  DH SET control  – Set to 200 feet. 6.   Radio altimeter   TEST switch   – Press and  hold.    "Minimum,  minimum"  will be  annunciated  once  followed  by  the illumination of the VA FAIL light. 7.   Radio Altimeter TEST switch – Release. c.   GPAAS  Modes  of  Operation.    The  GPAAS operates in the following modes of operation. (1)   Aural "Two Thousand" Advisory, Mode 1.   The aural advisory "Two Thousand" indicates that the aircraft  is  at  a  radio  altitude  of  2000  feet  AGL.    This advisory  is  canceled  when  valid  information  from  the radio  altimeter  is  lost,  during  climb,  or  whenever  the aircraft  is  out  of  the  operating  altitude  range  of  the radio altimeter. (2)   Hundred   Foot   Increment   Aural   Altitude Advisories,    Mode    2.        The    aural    advisories    "One Thousand,    Nine    Hundred,    Eight    Hundred,    Seven Hundred,  Six  Hundred,  Five  Hundred,  Four  Hundred, Three Hundred, Two Hundred, One Hundred" indicate that  the  aircraft  is  at  the  associated  radio  altitude  in feet   above   ground   level.    This  advisory  is  canceled when  valid  information  from  the  radio  altimeter  is  lost, during  climb,  or  whenever  the  aircraft  is  out  of  the operating altitude range of the radio altimeter. (3)   Aural  "Localizer"  Advisory,  Mode  3.  The aural advisory "Localizer" indicates that the aircraft has deviated   from   the   center   of   the   localizer   beam   in excess  of  1.3  to  1.5  dots.    The  localizer  advisory  is armed when a valid localizer signal is detected and the aircraft is below 1000 feet AGL.  It will be repeated no more than three times at 4-second intervals unless the aircraft is returned to less than 1.3 to 1.5 dots from the center of the localizer course.  The localizer advisory is disabled  when  a  valid  localizer  signal  has  been  lost, during   climb,   below   the   decision   height   set   on   the radio   altimeter,   or   if   the   navigation   receiver   is   not tuned to a localizer frequency. (4)   Aural   "Check   Gear"   Advisory,   Mode   4.   The  aural  "Check  Gear"  advisory  indicates  that  the aircraft   has   descended   to   500   feet   AGL   and   the landing  gear  is  not  down.    This  advisory  is  repeated once at 100-foot intervals down to 100 feet AGL. (5)   Aural    "Glideslope"    Advisory,    Mode    5.   The   aural   advisory   "Glideslope"   indicates   that   the aircraft  has  exceeded  1.3  to  1.5  dots  above  or  below the  center  of  the  glideslope  beam.    The  glideslope advisory  is  armed  when  a  valid  glideslope  signal  is detected  and  the  aircraft  is  below  1000  feet  AGL.    It will be repeated no more than three times at 4-second intervals unless the aircraft is returned to less than 1.3 to    1.5    dots    from    the    center    of    the    beam.        The glideslope  advisory  is  disabled  upon  loss  of  a  valid glideslope   signal,   during   climb,   on   a   localizer   back course,   below   the   decision   height   set   on   the   radio altimeter or, if the navigation receiver is not tuned to a localizer  frequency.    This  advisory  is  inhibited  by  the weight on wheels strut switch. (6)   Aural Advisory "Minimum, Minimum" Mode   6.      The   aural   advisory   "Minimum,   Minimum" indicates    that    the    aircraft    is    at    the    radio    altitude selected by the crew with the radio altimeter indicator decision height knob.  This advisory is canceled when valid information from the radio altimeter is lost, during climb, whenever the aircraft is above 1000 feet AGL, or whenever the aircraft is out of the operating altitude range of the radio altimeter. (7)   Aural  "Altitude,  Altitude"  Advisory,  Mode 7.  The aural advisory "Altitude, Altitude" indicates the approach   to   a   pre-selected   altitude   as   the   aircraft reaches a point 1000 feet from the selected altitude or, after  reaching  the  selected  altitude,  when  the  aircraft deviates more than 250 feet from the selected altitude. (8)   Aural  "Check  Trim,  Check  Trim,  Check Trim"   Advisory.      The   aural   advisory   "Check   Trim, Check  Trim,  Check  Trim"  indicates  that  the  autopilot has had a trim failure. (9)   Aural   "Autopilot"   Advisory.      The   aural advisory   "Autopilot"   indicates   that   the   autopilot   has disengaged. d.  Emergency  Procedures.     If  an  emergency or   malfunction   makes   it   necessary   to   disable   the GPAAS,    pull    the    VOICE    ADVSR    circuit    breaker located on the instrument panel.   Turn off the GPAAS audio by pressing the VOICE OFF switch. 3A-34.  STORMSCOPE. For    information    on    the    Stormscope,    refer    to Chapter 3, Paragraph 3-9. 3A-35.  TRANSPONDER SET (APX-100). For  information  on  the  transponder  set,  refer  to Chapter 3, Paragraph 3-10.