A 740-foot cargo ship was disabled and floating adrift in high winds about 540 miles southwest of Adak on Sunday.
The ship, the APJ Suryavir, registered in India, was battling 30-foot seas and winds close to 60 mph during part of the day, the U.S. Coast Guard reported.
There were 28 people on board.
The crew planned to abandon ship and move to a rescue ship that was due to arrive at the scene late Sunday night, said Petty Officer Walter Shinn.
The ship was drifting to the east, away from the Aleutian Islands.
Another cargo ship, the Maersk Altair, was in the vicinity and answered a Coast Guard call for help. But it had to slow down due to the weather and wasn't expected to reach the APJ Suryavir until the middle of the night.
The APJ Suryavir was heading empty from China to the Columbia River in Oregon when the main engine failed and would not restart. The ship had sea water ballast in its tanks to add weight and stability but was still not stable enough for the harsh conditions, said Shinn.
The Coast Guard sent a C-130 aircraft from Kodiak to check out the scene. That plane dropped a buoy to collect information on the currents and wind conditions. A second C-130 was to fly out to check on the APJ Suryavir early today, said Shinn.
A Coast Guard cutter docked at Dutch Harbor also set out to help but won't get to the site for four days.
The ship was not taking on water and has life rafts, survival suits and an emergency locator beacon, Coast Guard officials said. The ship is reported to have a 30-day supply of provisions.
The APJ Suryavir had engine trouble about four days ago, and its crew was working on the engine. They didn't radio for help until the weather turned bad late Sunday morning.