A Coast Guard vessel attempting to rescue a disabled sailboat got into trouble in rough seas early Tuesday morning near Kaa­awa, and its crew had to be rescued by a Coast Guard helicopter.

The Coast Guard boat lost power at 3:15 a.m. while attempting to tow the disabled 55-foot sailboat Doubloon off Laie, Coast Guard officials said in a news release.

A MH-65 Dolphin helicopter crew from Coast Guard Air Station Barbers Point arrived at about 4:03 a.m. and airlifted the 72-year-old sailboat skipper and the four members of the 45-foot Coast Guard rescue boat to a rugby field at the Brigham Young University in Laie.

An ambulance took a man from the sailboat to the hospital in stable condition.

The cause of the incident is under investigation.

The Coast Guard cutter Ahi was dispatched to the scene Tuesday to determine the best way to tow the disabled rescue vessel. Because there was no sign of the sailboat, Coast Guard officials say it might have sunk.

The incident began when the Doubloon reported problems at 9:49 p.m. Monday near Laie.

The rescue boat left the Coast Guard’s Sand Island station at 10:45 p.m. and arrived to aid the sailboat at 1:45 a.m.

When the rescue boat became disabled, the crew dropped anchor and called for help.

The MH-65 Coast Guard Dolphin helicopter crew and a HC-130 Hercules airplane crew then launched from Barbers Point.

The Honolulu Fire Department also launched a rescue boat and helicopter as part of the joint rescue effort.