Table 8-3.-Example Output of a Search Recommendation - Level I UNCLASSIFIED SEARCH  RECOMMENDATION  -  LEVEL  I SEARCH TIME: 1907940800 PROB  OF  SUCCESS:  100.% CUM  DETECTION  PROB:  100.% SEARCH AREA RECTANGLE: CENTER   LATITUDE: 6725N CENTER   LONGITUDE: 04736W LENGTH: 42.NMI WIDTH: 37.NMI ORIENTATION: 68.DEG TOTAL  AREA: 1563.SQ-NMI SEARCH  ASSET  INFORMATION  AND  RECOMMENDATION ASSET NAME SPEED ALTITUDE SENSOR O N    S T A    A R EA COVERED (KT) (FEET) (HHMM) (%) (SQ-NMI) P3 200. 1000. v 0500 100. 1563. SAR EFFORT 0800Z 19 JUL 94 UNCLASSIFIED .  The  RAY  program  uses  a  single  sound  speed the  deepest  depth  of  that  sound  speed  profile,  the profile, generated by the Sound Speed Profile (SSP) Raytrace module extrapolates the sound speed profile to program. Thus, sound speeds used-in this program are a function of depth, but not range. l  In  output  displays,  horizontal  and  vertical plotting  scales  are  often  different,  resulting  in  an apparent  difference  between  the  angle  of  incidence  and the angle of reflection with respect to a locally sloping bottom. . A positive ray is downgoing; a negative ray is upgoing. l If the source is located at the surface (that is, source depth of zero), the operator should not select any negative (upgoing) rays. l  The  module  traces  only  outgoing  rays.  If  the angle of reflection from a sloping bottom is +89.9°, then the ray is terminated. l  Computed ray diagrams are very sensitive to the user’s  selection  of  launch  angles  and  source  depth,  as well  as  bathymetry  and  sound  speed, l  The RAY program uses the sound speed profile to  calculate  ray  paths.  If  variable  bottom  depths,  either automatically  retrieved  or  manually  supplied,  exceed the deepest variable bottom depth provided . Because of computational limitations a 0° ray cannot be traced Whenever a 0° ray is requested or expected on the output diagram, a +0.01° ray and a -0.01° ray will be traced. .  Because  temperature  and  salinity  are  relatively stable below 2500 m, sound speed profiles reaching 2500  m  are  accurately  extrapolated.  Extrapolations  of sound speed profiles that do not extend to 2500 m, however, are suspect. Computed ray paths that descend to  depths  where  extrapolated  sound  speeds  are  suspect should be used with caution. FUNCTIONAL DESCRIPTION The  principle  means  of  detection  used  in antisubmarine  warfare  (ASW)  employs  acoustic  energy, Water,  a  poor  medium  for  the  transmission  of electromagnetic (EM) energy, is an excellent conductor of  acoustic  energy  or  sound.  Sound  is  a  wave phenomenon,  consisting  of  alternate  compression  and refraction of the medium. The speed of sound, or speed at  which  the  acoustic  waves  advance  through  the medium,  depend  on  certain  characteristics  of  the 8-6