Sperry Marine won multiple type approvals from classification societies and national authorities for the VoyageMaster Voyage Data Recorder (VDR) system. Organization (IMO) carriage requirements, which come into effect July 1, 2002. The VoyageMaster VDR, similar to an aircraft "black box," records vital information concerning the ship's position, movement, physical status and command and control for the period leading up to and following an incident. The data, including voice recordings from bridge microphones and VHF radio, is stored in a hardened memory capsule for recovery and analysis by safety investigators following an incident at sea.