A Concept Design for an Ultra-Long-Range Survey Class AUV

Gliders and flight-style autonomous underwater vehicles (AUVs) are used to perform perform autonomous surveys of large areas of open ocean. Glider missions are characterized by their profiling flight pattern, slow speed, long range (1000s of km) and many month mission duration. Flight-style AUV missions are faster, of shorter range (100s of km) and multi day duration. An AUV combining many aspects of both vehicle classes would be of considerable value. This paper investigates the factors that affect the range of a traditional flight-style AUVs. A generic range model is outlined which factors in the effects of buoyancy on the range. The model shows that to create a very long range AUV it is necessary to reduce the hotel load on the AUV to the order of 1 W and to add wings to overcome the vehicle´s positive buoyancy whilst travelling at the reduced speed required for long range. Using this model a concept long range AUV is outlined that is capable of travelling up to 5000 km. The practical issues associated with achieving this range are also discussed.