TM  1-1520-240-10            8-2-13 8-2-23.  Hover Check. Perform the following check at a hover. 1.   Flight controls — Check flight controls for cor- rect response. 2.   Systems instruments — Check normal. 3.   Flight instruments — Check as required. a.   VSI, barometric and radar altimeters — Indicate climb and descent. b.   Turn  pointers,  heading  indicators  and magnetic compass — Indicate turns right and left. c.   Slip indicator — Ball free in race. NOTE Rapid rotation of the pitch and roll trim knobs on  the  attitude  indicator  may  cause  abrupt pitch and roll attitude changes with AFCS on. d.   Attitude Indicator — Indicate nose high, nose low, banks right and left. e.   Airspeed indicator — Check. 4.   LCTS — Check retracted. F 5.   GROUND CONTACT indicating lights check — Both off. 6.   AFCS  —  Check  as  follows:  (First  flight  of day). a.   SYSTEM SEL switch — NO. 1 Check helicopter  stable  with  no  abrupt  en- gagement  error.  Check  NO.  2  AFCS OFF caution on. b.   SYSTEM  SEL  switch  —  NO.  2  Check helicopter stable with no abrupt engage- ment  error.  Check  NO.  1  AFCS  OFF caution on. c.   SYSTEM SEL switch — Both. Check he- licopter  stable  with  no  abrupt  engage- ment error. Check both AFCS OFF cau- tion capsules extinguished. 7. ⁷¹²HIT/^714A PAT   —   Perform   as   re- quired. 8.   Power Check — Perform as required. 8-2-24.  Before Takeoff. * 1.   Systems — Check indications of the follow- ing: a.   Rotor — Check as required. b.   Torque. c.   Engine. d.   Transmission. e.   Fuel. f. 712 Master caution panel. g. 714A Caution/Advisory panel. * 2.   PARKING BRAKE — As required. * 3.   AFCS SYSTEM SEL switch — As required. * 4.   CYCLIC TRIM switch — Check. * 5.   SWIVEL switch — LOCK. * 6.   Transponder — As required. F* 7.   Crew,  passengers,  and  mission  equipment — Check. 8-2-25.  VMC Takeoff. Refer to Aircrew Training Manual (ATM). 8-2-26.   Hover. Refer to Aircrew Training Manual (ATM). To engage radar altitude hold perform the following: WARNING Do not use radar altitude hold in forward flight  over  terrain.  It  may  not  provide adequate  terrain  clearance  in  rapidly changing terrain. Use radar altitude hold to  maintain  a  constant  absolute  altitude during hover or forward flight over water. RAD ALT hold can be used to a maximum of 1,500 feet absolute altitude. a.  Radar  altimeter  —  ON.  Check  that  pointer  has rotated from behind the mask, the digital display is lit, and the OFF flag is out of view. b.  Fly to desired altitude. c.  RAD ALT select on AFCS panel — Press. Check ENGAGED light ON. The radar altitude hold feature of the AFCS will maintain a constant altitude. d.  To  select  another  altitude,  press  the  THRUST CONT  BRAKE  TRIGGER.  Fly  to  desired  altitude  and release the THRUST CONT BRAKE TRIGGER. The alti- tude at the moment the trigger is released will be the new altitude.