At approximately 1645 Central time, the helicopter disappeared under unknown circumstances. The status of the Commercial pilot and the two passengers aboard is unknown. Visual conditions prevailed for Part 135 on-demand air taxi flight. The helicopter was engaged in several flights between oil platforms in the Gulf. No distress calls were received by the operators dispatch or any aircraft flying in the area. When the helicopter failed to make its required position reports, a search was initiated. Search and rescue efforts were suspended on October 10, 2005.