TM 55-1520-240-T 3 - 1 . 3     P R O X I M I T Y     S W I T C H     O P E R A T I O N     ) 3-1.3 INITIAL SETUP Applicable Configurations: W i t h o ut Tools: Aircraft  Mechanic’s  Tool  Kit, NSN    5180-00-323-4692 Jack  1214-151  or  equal Materials: None Personnel Required: Avionic Mechanic Medium Helicopter Repairer (2) References: TM   55-1520-240-23 Equipment Condition: Battery Connected Electrical Power On Hydraulic Power On Aft Landing Gear Access Panels Open Flight Controls Closet Acoustic Blanket Removed Flight Controls Closet Panel Open TASK RESULT TASK RESULT CHECK CIRCUIT BREAKERS 1.  Check   that  following   circuit   breakers   in NO. 1 PDP  are  closed: AC AFCS  NO.  1  (1) NAV  COPLT  VGI  (2) DC AFCS  NO.  1  (3) 2.  Check  that  following  circuit  breakers  in NO. 2 PDP  are  closed: AC AFCS  NO.  2  (4) NAV  PILOT  VGI  (5) DC AFCS  NO.  2  (6) NAV  CONT  VGI  (7) CHECK LEFT PROXIMITY SWITCH If any circuit breaker ( 1 through 3) is open, close it. If AFCS NO. 1 circuit breaker (1) opens again, go to task  11-3.4. If NAV COPLT VGI circuit breaker (2) opens again, refer   to   TM   11-1520-240-20. If AFCS NO. 1 circuit breaker (3) opens again, go to task  11-3.6. If any circuit breaker (4 through 7) is open, close it. If AFCS NO. 2 circuit breaker (4) opens again, go to task   11-3.10. If NAV PILOT VGI circuit breaker (5) opens again, refer  to  TM  11-1520-240-20  for  troubleshooting  in- formation. If AFCS NO. 2 circuit breaker (6) opens again, go to task   11-3.11. If NA\/ CONT VGI circuit breaker (7) opens again, refer  to  TM  11-1520-240-20  for  troubleshooting  in- formation. 3.  Set   SYSTEM   SEL   switch   (8)   to   1. 4.  Position  observer  at  flight  controls  closet to  watch  output  shafts  (9  and  10)  of  DASH actuator  (11). 5.  Move   pilot’s   pitch   and   roll   control   stick Output shaft (9) on DASH actuator (11) shall not grip   (12)   forward. move.  If  it  moves,  go  to  task  11-3.15. 6.  Return   pilot’s   pitch   and   roll   control   stick grip  (12)  to  neutral. 7. 8. 9. 10. Keep   movement   to   minimum while   aircraft   is   on   jack.   Personnel injury   and   damage   to   equipment can  result  if  aircraft  should  slip  off jack. Raise   left   aft   end   of   helicopter   with   jack (13)  but  do  not  install  static  lock  (14). Jack  helicopter   until  wheel  (15)  is  off  ground and  shock  strut  (16)  is  fully  extended. Move   pilot’s   pitch   and   roll   control   stick Output shaft (9) on DASH actuator (11) shall move. grip   (12)   forward. If  it  does  not,  check  proximity  switch  adjustment.  If adjustment  is  correct,  go  to  task  11-3.15. Return   pilot’s   pitch   and   roll   control   stick grip   (12)   to   neutral. Lower jack (13) until clear of helicopter and remove it. CHECK RIGHT PROXIMITY S WITCH 11. 12. 13. Set SYSTEM SEL switch (8) to 2. Repeat steps 4, 5, and 6 above. Output shaft (10) on DASH actuator (11) shall not move.  If  it  moves,  go  to  task  11-3.15. Repeat  steps  7  through  10  above,   except Output shaft (10) on DASH actuator (11) shall move. jack  right  aft  end  of  helicopter. If  it  does  not,  check  proximity  switch  adjustment.  If adjustment  is  correct,  go  to  task  11-3.15. FOLLOW-ON    MAINTENANCE: TM   55-1520-240-23 Close aft landing gear access panels. Close  flight  controls  closet  and  install  blanket. GO TO NEXT PAGE 3-10  Change 3