The duration that the AUV can remain on the seafloor is dependent on the amount of warning that it has, knowing that it will be remaining at the seafloor when it first enters the water. For example if the AUV has run a full mission and right as it is about to be pulled from the water needs to travel back to the seafloor due to a sudden situation that arises on the surface vessel, the AUV can remain at the seafloor for up to 42 hours before it will surface and communicate its location at the surface via satellite. If we have 4 hours of notice before the surface ship needs to leave the area, such as major weather events, all vehicles in the water will have entered the water knowing that they will be there for an extended period of time and can remain stationed at the seafloor for a total of 4 days.
See also question D.18: How will the underwater robot respond to emergencies or system failures?
