TM 1-1500-204-23-1 a.   Deterioration Factors.    Deterioration  problems result   from   sand   and   dust,   high   day   temperatures, temperature fluctuations, ultraviolet radiation, and terrain.  Considerations for each problem are explained in the following paragraphs. (1)  Sand  and  dust.    The  large  quantities  of loose sand and dust create serious erosion problems for rotor   blades,   propellers,   turbine   engine   compressors, windshields  and  other  exposed  surfaces  of  the  aircraft While  sitting  on  the  ground,  the  aircraft  is  exposed  to blowing sand and dust from frequent desert windstorms and  sand  and  dust  clouds  created  by  vehicular  traffic and  operation  of  other  aircraft  nearby.    Sand  and  dust particles  collect  on  all  surfaces  of  the  aircraft  and  will penetrate  almost  any  crack  or  crevice  to  accumulate Inside     the     aircraft.          Electronic     gear     and     optical equipment    are    very    susceptible    to    sand    and    dust. Weapons  are  particularly  susceptible  since  many  parts are often covered with a light coat of lubricant. (2)  High  day  temperature.    In  the  desert, heat creates serious problems for people and equipment.    The  temperature  inside  a  parked  aircraft which has been closed up to keep the sand and dust out can    reach    temperatures    much    higher    than    outside temperatures    Extreme    heat    can    cause    the    failsafe device   in   electronic   gear   to   shut   the   equipment   off. High temperatures can cause lubricants to break down, distort seals and gaskets, and result in Increased leaking problems.    Other  problems  due  to  high  temperatures include softening of plastics, high stress on pressurized containers, and shortened battery life. (3) Temperature fluctuations Daytime temperatures  can  reach  over  100 °F  (38°C),  while  night time  temperatures  could  reach  freezing  (or  close  to  it) The condensation resulting from this extreme temperature variation contributes to increased corrosion. (4)      Ultraviolet   radiation.      The   abundant desert   sunlight   produces   a   high   level   of   ultraviolet radiation which can cause unprotected plastic components  to  become  very  brittle  and  easily  cracked Ultraviolet   radiation   also   accelerates   deterioration   of nylon webbing used in seats and restraint systems. (5)  Terrain.    The  terrain  causes  problems with  moving  aircraft  and  associated  support  equipment on the ground Sand can bog a vehicle or aircraft down to  the  axles.    A  condition  known  as  Cap  Rock  Is  often encountered  The  terrain  appears  rocky,  however,  the substrate will not support weight and a vehicle can sink up  to  the  frame  when  attempting  to  travel  over  Cap Rock.    Aircraft  tires  can  easily  be  damaged  In  rocky desert terrain. b.    Precautions.    Maintenance      personnel      will observe    the    following    precautions    as    a    guide    to successful performance of duty under desert conditions: WARNING Severe  burns  can  result  when  bare skin  touches  metal  parts  of  aircraft or equipment. ·    Exercise  caution  when  touching  aircraft  surfaces  or metal   tools   that   have   been   exposed   to   the   sun. Wear gloves and use mats or pad, when practical, to prevent burns or blisters. ·    Use   extreme   care   when   handling   engine   fuel   at temperatures    above    120°F    ( 49^oC),    to    prevent possible   sparks   and   explosion.      Open   gasoline drums with bronze or other nonsparking tools. ·    Electronic  gear  and  optics  must  be  shielded  from direct  sunlight  and/or  otherwise  cooled  for  efficient operation. c.    Inspection  and  Maintenance.    The  following procedures  are  for  the  inspection  and  maintenance  of aircraft operating in desert conditions: NOTE Aircraft should be cleaned daily Frequent use of a vacuum cleaner will prevent accumulation of sand and dust in  aircraft.    Pay  particular  attention  to abrasion/erosion problems during Inspections. (1)  Inspect  bungee  cords,  seals,  tires,  etc., frequently for blisters and other signs of deterioration. (2)   Inspect   vibration   Isolators   every   two weeks  and  replace  where  cracking  or  permanent  set  is excessive. (3)        Keep    a    chart    showing    engine    oil consumption.    A  sharp  rise  on  the  chart  will  indicate faulty   or   inefficient   engine   operation.      An   inefficient engine should not be continually operated.  It is better to correct  the  trouble  so  the  engine  will  operate  at  peak performance. (4)    Inspect,    clean,    or    replace    filters    at regular intervals.  Sand and dust quickly choke fuel and oil  filters  and  air  cleaners.    Keep  an  adequate  reserve stock of cleaners and filters. 10-7