The Coast Guard station in Astoria received a brief mayday call at about 10 a.m. Friday and tracked the radio signal to an area where the Coast Guard sent a 47-foot boat and an MH-60J helicopter. AUDIO: Mayday Call From Capsizing Boat

An observer in the Cape Disappointment observation tower spotted six people stranded on top of the overturned boat, waving, the Coast Guard said.

The helicopter lowered a rescue swimmer to help bring the six men safely off the vessel and over to the awaiting crew of the motor lifeboat. RAW VIDEO: Coast Guard Rescue Near Cape Disappointment

The six men were not hurt.

The six Oregon National Guardsmen were on a training mission when their boat capsized crossing the Columbia River at a location known as Peacock Spit. The cause of the capsizing is under investigation.