New Zealand sports broadcaster Miles Davis says bad weather is making the rescue mission almost impossible for his Navy diver son searching for the missing Argentinian submarine.
William Davis is on board the British polar explorer the HMS Protector, which was on its way to Antarctica when it was called back to join the search for the ARA San Juan.
The old submarine, built in 1984, has been missing for five days in rough seas with 44 people on board.
Miles Davis says his son has told him that "the rough seas are making it hard to locate anything and the forecast is not expected to clear for a couple of days".
Rescue aircraft and vessels have ramped up the search after a series of apparent attempted distress calls yesterday raised hopes they may be alive.