Acoustic positioning technology from Sonardyne Inc, Houston, was selected to play a key role in a recent expedition aiming to solve one of the greatest mysteries of the 20th century. A Bluefin Robotics AUV (Autonomous Underwater Vehicle) was equipped with a Sonardyne Ranger 2 underwater target tracking system which was used by The International Group for Historic Aircraft Recovery (TIGHAR) to search for the remains of the Lockhead Electra aircraft flown by Amelia Earhart during her failed circumnavigation attempt in 1937.