The French sailor's yacht lost its mast and suffered hull damage in rough seas on Friday, several months into the trip.
Later, the experienced yachtsman activated his emergency beacon and abandoned the yacht for a life raft.
An aircraft from the Australian Maritime Safety Authority (AMSA) arrived on the scene about 500 nautical miles south-west of Hobart on Friday night and dropped a second life raft and communications equipment to the uninjured man.
AMSA spokeswoman Jo Meehan says passenger ship Orion is on its way to the Frenchman, but it could be a few days before he is rescued from his raft.
"The conditions in the area are not favourable. There are some high seas and rough winds," she said.
"The solo sailor's yacht was demasted and suffered some hull damage in rough weather conditions. We were informed of this yesterday morning.
"We spoke with the sailor at the time and he didn't declare distress, however, the conditions did deteriorate and he set off his emergency beacon."
However, Ms Meehan says planes are trying to radio non-English speaking fishing boats which may be able to reach the yachtsman sooner.
"We have had to get translators to come onto the various aircraft that will be in the area so that we can get information about his condition," he said.
"We have identified other vessels that are in the area of the life raft and are trying to gain communication with those."