navigate <ship>|<fleet> <directions>
    sail ships. <directions> are

    u  - up                         8 - up
    /r - up right                   9 - up right
    r  - right                      6 - right
    \r - down right                 3 - down right
    d  - down             -OR-      2 - down
    /l - down left                  1 - down left
    l  - left                       4 - left
    \l - up left                    7 - up left
    e  - end of sailing             . - end of sailing
    v  - look at current sector     5 - look at current sector
         (shows sea versus harbor)

    Costs vary with ship type and technology level. Watch out for mines.
    Movement prompt is:
       <flagship mobility:minimum mobility:position>
    You can't navigate fleet '*'. The flagship is the first ship given when
    the fleet was set up. When the flagship can no longer navigate, the
    whole fleet stops. Sailing into a hurricane can damage your ships. Ships
    use less mobility for navigating as your country's tech factor increases.
Doc: ships, weather
Help: ships, fleet, weather, forecast, move, fly, load, unload
