TM 1-1500-204-23-1 Place   chocks   fore   and   aft   of   main   landing gear  wheels.    Do  not  use  parking  brakes  as substitutes  for  chocks.    Use  steel  chocks  for snow or ice operating only.  Use sandbags on steel   matting.      Use   wooden   chocks   for   all other  operations.    Set  brakes  only  after  they have cooled. NOTE Do   not   set   brakes   of   aircraft   in   a hangar   or   outside   during   subzero temperature Service     aircraft     systems     as     required     by applicable   maintenance   manual.      Exercise care during servicing to prevent moisture from entering systems being serviced. Avoid  parking  aircraft  in  wet  or  slushy  areas saturated with fuel or oil. Install pitot tube covers and wheel covers. • Move  controls  to  neutral  position  and  lock  by either internal or external means. • When parking helicopters overnight for storage,    or    during    adverse    weather,    set ground  handling  wheels  (when  applicable) in retracted position. • Rotate      or   fold   main      rotor   blades      (when applicable)    in    accordance    with    instructions contained in applicable maintenance manual. e. Preparation of Aircraft for Storms.  The following general precautions are to be observed when storms are anticipated: Install   all   protective   covers   and   shields   to protect  aircraft  from   accumulation  of snow, frost, or ice. NOTE If wings are wet or a freezing rain is expected,  cover  aircraft  with  a  coat of    anticing    and    deicing-defrosting fluid,    MIL-A-8243,    before    installing fabric covers. Refer  to  the  applicable  aircraft  maintenance manual  for  the  use  of  spoilers  if  severe  wind is expected. Ensure  aircraft  is  chocked  and  tied  down  in accordance with applicable maintenance manual storm procedures. In case of emergency, tie down aircraft using trees     or     arctic-type     (dead-man)     mooring anchor. f. Flightline  Equipment.      All   flightline   equipment should be inspected and functionally checked to ensure safety prior to use. (1) General inspection. The following paragraphs describe inspection requirements for flightline equipment. (a) Cleanliness.  Inspect equipment internally and  externally  for  cleanliness.    Equipment  will  be  dry and free of mud or other debris. (b) Serviceability.          Perform     serviceability inspection of all new equipment. (c) Lubrication.      Lubrication   will   conform   to the applicable maintenance manual. (d) Oil  seals.    Inspect  oil  seals  for  leakage. Oil seals that are wet and show only a slight drip, after operation  or  standing,  are  considered  as  seeping  and are acceptable.  Seals that show definite leakage will be replaced. (e) Performance.  Ensure that ground support equipment is in such condition that its performance will approximately    equal    new    equipment    and    meet    all general safety requirements. (2) Functional check. The following procedures    explain    functional    checks    for    flightline equipment. (a) Check all levers, switches, valves, shutters, etc ,to ensure proper operation. (b) Check  all  meters  and  gauges  for  proper operation and adjustment. 3-3