Why does the media keep referring to these things as submarines? I find what Elon brought to the table as far as design/usability pretty poor, all that money,talent and manufacturing availability and he comes up with something that'a a giant leap backwards.
DPV(diver propulsion vehicles) or 'scooter' are not new or rare in cave diving.
Elon Musk's 'submarine'
Seems like a poor design especially compared to what's out there for thew last 10 years. The need for all that external weight? Compare the size to those below.
Scooters currently being used as compared to above unit.
These scooter are more then capable of going the 2 KM there and back. Now if the use of scooters would be useful here I can't say but pretty sure if scooters would have worked the on site cave divers/rescue team would have access to scooters.Looking at some of the rescuers on site and their experience, if scooters could be used they would have been used,these scooters are not that uncommon.