He says a fishing vessel is en route to pick her up.
Until late Thursday night, Sunderland had not been heard from by her family since Thursday morning when they spoke over a satellite phone.
"She has been prepared for this for a while so she's got all the right equipment as well, which definitely helps out. Everything is prepared for this situation," said Abby's brother, Zac Sunderland.
Zac knows what his sister is going through. He set around the world and set a record when he was 17 years old.
Just around 6 a.m. Thursday, two emergency beacons on Sunderland's boat signaled that there was trouble.
"She set off her manual emergency locater beacons. The one that floats from the boat when the boat sinks was not set off so we're pretty hopeful that the boat is still floating. Right side up or upside down, it doesn't matter," said Jeff Casher, support team associate.
Casher says he and the family spoke to her on a satellite phone trying to help her repair an engine problem. Communications were spotty but she told them there were strong 60-knot winds and 30-foot swells. The radar was ripped off the boat. She said she would call back, but wasn't heard from for many hours.
Sunderland departed from Marina del Rey in January. Sunderland has had several setbacks on this journey. Earlier on, she had to make a stop in Mexico. Recently, she had mechanical problems and made it to South Africa for repairs. She still planned on completing her trip.
In her blog, Sunderland wrote, "The last few days have been pretty busy out here. I've been in rough weather for a while with winds steady at 40-50 knots with higher gusts."
Her current location is about 500 miles north of Antarctica in the Indian Ocean.
On Thursday, Sunderland's friends at Blessed Hope Chapel in Simi Valley near her home prayed for her safe return.
"I really wish I could see her and just hope that she gets through this and see how everything goes," said Zac Sunderland.
The emergency beacons are still working and still indicating where her boat is. Several vessels are on their way to that location.
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