It involved four people onboard a "sinking boat" on the Manukau Bar.
The quartet were later spotted by the Auckland Westpac Rescue Helicopter's chief intensive care paramedic Karl Taylor "clinging to the bow of the boat".
Shortly afterwards they were pulled from the water by four recreational boats, before being transferred to a Coastguard vessel.
The Westpac Rescue chopper was then stood down and returned to its base.