TM 1-1500-204-23-1 NOTE ·  Starting    oil    pressure    may    exceed standard   oil   pressure   gauge   limits. This    condition    is    not    considered dangerous unless the pressure remains   high.      Takeoff   should   be delayed until oil pressure drops with range,    as    specified    in    applicable maintenance manual. ·  A  hot  start  occurs  when  the  engine starts, but the exhaust gas temperature exceeds specified limits. This is usually caused by an excessively    rich    fuel    air    mixture entering   the   combustion   chamber. The   fuel   to   the   engine   should   be shut off immediately. ·  False or hung starts occur when the engine  starts  normally  but  the  rpm remains   at   some   low   value   rather than increasing to the normal starting  rpm.  This  is  often  the  result of insufficient power to the starter, or the    starter    cutting    off    before    the engine   starts   self-accelerating.      In this case, the engine should be shut down. (2) Ground   checks.        To    ensure    proper operation, perform the following procedures before taxiing or takeoff. (a) Inspect   all   aircraft   systems   and surfaces, with emphasis on systems and surfaces directly affected by low temperatures. (b) Inspect controls and trim tabs for freedom of movement. CAUTION Do    not    apply    heat    directly    or    too rapidly against windshield and windows as there is danger of cracking, crazing, and discoloration. (c) Inspect    cabin    heat,    defrosting, and anti-icing systems. (d) Inspect hydraulically-operated equipment.        Cycle    system    several    times    if    sluggish operation is evident. (3) Shutdown.  Shut down turbine engines in accordance with the applicable maintenance manual. 3-11.  Runup   and   Taxiing.      Nonrated   personnel   who start,  run,  warmup  test,  taxi  or  otherwise  operate  aircraft on    the    ground    will    be    fully    qualified,    demonstrate satisfactory   ability,   and   be   authorized   to   perform   such duties, in accordance with AR 95-1.  Nonrated personnel cannot  run  up  rotary  wing  aircraft  under  any  condition. General   safety   procedures,   taxiing,   and   postflight   and parking are covered in the following paragraphs. a. Safety Procedures. General safety procedures   for   runup   and   taxiing   are   provided   in   the following steps. (1) Chock aircraft securely before attempting an engine runup. (2) Check  runup  area  carefully  to  prevent propeller or jet blast from throwing ice and snow on other aircraft. NOTE Some  instruments  will  give  erroneous readings due to cold.  These readings can  be  compensated  for  or  corrective action   may   be   taken.      For   specific instruments  and  their  characteristics, consult applicable maintenance manual. (3) Position ground crew to ensure adequate guidance when aircraft is maneuvered close to other aircraft, buildings, or obstructions, or in gusty or high winds. (4) Check  that  brakes  are  not  frozen,  and that aircraft will roll before attempting to taxi from parking space. (5) Free  tires  that  have  become  frozen  to surface  by  application  of  heat  or  over-inflation.    Do  not allow heat to exceed 160 °F (71°C). NOTE Immediate  freeing  action  cannot  be expected  from  tires  that  have  been over-inflated.    A  time  period  of  one- half  to  one  hour  may  be  necessary for tires to become free. 3-18