1.   In World War II, Arthur Berry was an underwater defense specialist, planting nets and sonar buoys to protect Navy battle ships.

2.   A Pentagon official said the Kitty Hawk dropped a sonar buoy when it could not identify the submarine on its radar screen.

3.   At the harbor museum, a microphone attached to a sonar buoy out in the ocean relays the eerie sounds of the whales calling to each other.

4.   The Orion dropped a sonar tracker buoy designed to drift next to the life raft so it could be found quickly by future searchers.

5.   The sonar buoy was dropped next to the yacht from a rescue plane, the Royal Australian Air Force said.

6.   The sonar buoy was later dropped near the boat and detected no signs of life, the air force said.