Elon Musk's kid-size submarine is headed to Thailand, but rescuers probably won't need it

Mini-sub to the rescue! Or, maybe not.

On Sunday afternoon, Elon Musk tweeted that the kid-size submarine his team had developed to assist with the rescue of Thai boys trapped in a cave was en route to Thailand. He expected it to arrive around 11 p.m. Monday, local time.

But phase two of the rescue is already underway, and may in fact be over by the time the sub arrives.