TM 55-1510-220-10 NOTE The AP TRIM FAIL annunciator will extinguish  by  pressing  the  AP/YD disconnect   button   on   the   control wheel to the second detent. m. Repeat    steps    (i)    thru    (1)    above    using opposite commands. n. Autopilot Engage. o. HSI  heading  marker  Move  to  command  a bank on flight director indicator. p. GO-AROUND  switch  Press  and  verify  that GA  annunciator  light  illuminates,  autopilot disengages, and that flight director indicator commands a wingslevel 7° nose-up attitude. q. TEST switch (pilot's flight director indicator) Press     and     verify     that     attitude     display indicates an additional 10°  pitch up and 20° right roll, and GYRO flag is visible. *7. Autopilot   trim   fail   system   Check   as   follows:   a. Autopilot   Engage.      Command   DN   on   AP   pitch wheel and hold TRIM TEST switch when elevator trim wheel starts to rotate. b. Verify   that   autopilot   disengages   and   AP TRIM FAIL and MASTER WARNING lights illuminate within 10 seconds.  Repeat steps (a) and (b) using opposite commands. 8. Avionics Check and set as required. 9. Flaps Check. 10. Altimeters Check and set. 8-36.  * TAXIING. CAUTION Excessive   use   of   brakes   with   the increased weight of this aircraft will increase   the   possibility   of   brake failure and/or brake fire.  Judicious use  of  the  brakes  is  recommended with coordinated use of beta range. Taxi speed con be effectively controlled by the use of  power  application  and  the  use  of  the  variable  pitch propellers in beta range.  Normal turns may be made with the   steerable   nose   wheel;   however,   a   turn   may   be tightened    by    using    full    rudder    and    inside    brake    as necessary.  Turns should not be started with brakes alone, nor  should  the  aircraft  be  pivoted  sharply  on  one  main gear. 1. Brakes Check. 2. Flight instruments Check for normal operation. 8-37.  ENGINE RUNUP. 1. Mission control panel Set. 2. Propeller manual feathering Check as follows: a. Condition lever LOW IDLE. b. Left propeller lever FEATHER.  Check that propeller feathers. c. Left propeller lever HIGH RPM. d. Repeat procedure for right propeller. 3. Autofeather Check as follows: a. Condition levers LOW IDLE. b. Autofeather   switch   Hold   to   TEST.      (#1 AUTOFEATHER   and   #2   AUTOFEATHER advisory  annunciator  lights  should  remain extinguished.) c. Power   levers   Advance   to   approximately 22%  torque,  then  move  autofeather  switch to TEST.  Both #1 AUTOFEATHER and #2 AUTOFEATHER advisory annunciator lights should illuminate. d. Left power lever Retard. a. At  approximately16  to  21%  torque,  check #2   AUTOFEATHER   advisory   annunciator extinguished. b. At approximately 9 to 14% torque, check #1 AUTOFEATHER  advisory  annunciator  light extinguished.        (Left    propeller    starts    to feather.) 8-16