It is a surveillance technology in which an aircraft determines its position via satellite navigation or other sensors and periodically broadcasts it, enabling it to be tracked.
AHTS - Anchor Handling Tug Supply Vessel
These types of vessels are mainly built to handle anchors for oil rigs, tow them to location, and use them to secure the rigs in place. AHTS vessels sometimes also serve as Emergency Response and Rescue Vessels (ERRVs) and as supply transports.
AIS - Automatic Identification System
It is an automatic tracking system that uses transceivers on ships and is used by vessel traffic services (VTS). AIS information supplements marine radar, which continues to be the primary method of collision avoidance for water transport. Although technically and operationally distinct, the ADS-B system is analogous to AIS and performs a similar function for aircraft.
Information provided by AIS equipment, such as unique identification, position, course, and speed, can be displayed on a screen or an electronic chart display and information system (ECDIS).
AOC - Air Operator's Certificate
It is the approval granted by a national aviation authority (NAA) to an aircraft operator to allow it to use aircraft for commercial purposes. This requires the operator to have personnel, assets and systems in place to ensure the safety of its employees and the general public. The certificate will list the aircraft types and registrations to be used, for what purpose and in what area – specific airports or geographic region.
ATO - Approved Training Organisation
An organisation that provides training courses and qualifications to a defined and industry-agreed training standard. It is the highest level of approval a training provider can receive.
AV - Accommodation vessel
These types of vessels are used to accommodate personnel at sea. They remain located in direct proximity to the work site to minimise transit time to the offshore structures / wind farms (OWFs) and maximise the personnel's working time. They are also known as floating hotel or floatel.