                               Command : SONAR

 SYNTAX:
   [##:##] Command: sonar <SHIP/FLEET>

The  conar  command allows ships to look for submarines and submarines to look
for ships.

In the current implementation, sonar works similar to lookout.  The major dif-
ference  is  that  a  submarines cannot use lookout to sight ships.  Likewise,
submarines cannot be sighted by ships via lookout.

There are two aspects to sonar - passive and active sonar.

ACTIVE SONAR

This is the most visible form of sonar.  It is simply a ship's ability to  use
sonar  pings  to  detect  other  ships.  The range of a ship's active sonar is
identical to the range that it can sight ships via lookout.  (see  info  look-
out) When you type "sonar 25", you are using active sonar.

                               Command : SONAR

PASSIVE SONAR

This is more subtle.  Passive sonar is a ship's ability to hear sounds, mainly
active sonar pings.  When a ship pings you with active sonar, you  can  detect
that ping.  If a ship with sonar gets pinged, that country receives a telegram
saying "Sonar ping from x,y detected by ship Z!"  In its  current  implementa-
tion, passive sonar is the ability to detect a ping.

When  a  ship  emits  a  ping,  that  ping has to travel out to a target ship,
reflect off of it, and then return to its source.  So, in order  to  detect  a
ship X sectors away, a sonar ping must be able to travel 2X sectors - from the
source to the target, and back to the source.  So, if a ship  can  use  active
sonar  to  detect ships X sectors away, passive sonar can detect active sonars
from 2X sectors away.  So the range at which you can  detect  sonar  pings  is
twice the range at which you can use sonar.

The  active and passive sonar modes means that you want to be careful when you
use sonar, because you will tell others where you are long before you actually
detect  them.   This also gives you some warning before you get your submarine
attacked, as enemy ships have to use sonar to find you.  The key to  submarine

                               Command : SONAR

warfare is "run silent", meaning use your sonar only when you have to.

On the other hand, destroyers are designed to hunt subs.  A destroyer guarding
a player's coast should use sonar often, especially if it has other destroyers
nearby to support him if he gets in trouble.

For example:
   [##:##] Command: sonar 24

   Groonland (#1) patrol boat #10 @-13,7
   Curmudgeon (#4) heavy cruiser #36 @-14,6
   Groonland (#1) oil derrick #41 @-14,6
   Groonland (#1) tender #53 @-14,6
   Groonland (#1) submarine #53 @-14,6
   Groonland (#1) nuclear sub #53 @-14,6

                            Concept : plane-sonar

Planes  with  the  ASW  ability  (if the ASW_PLANES option is enabled) can use
sonar while on recon missions. See info recon for more details.

See also : coastwatch, ship-types, sector-types, radar, recon

