Pilot Dan O'Reilly spotted a figure holding tightly to the back of the boat.
"The boat was rocking to and fro, wallowing in the water," he said.
The initial plan to rescue the man from the yacht was abandoned as the extremely windy conditions threatened to snag the winch in the rigging.
Instead the petrified boatie climbed into his dinghy and floated 10m from the back of the boat where rescue medic Leah Baker was able to winch him to safety.
O'Reilly said when the man was very emotional when he reached the helicopter.
"He was thanking Leah profusely. He was panicked because he was by himself, and that added to his inability to reef the sail."
Back at the helicopter base the man was assessed by St John medics and, miraculously, was uninjured, but had to leave the boat behind.
A Rescue Co-ordination Centre (RCCNZ) spokesperson said being equipped and having reliable gear plays a major part in keeping boaties safe.
"Your safety depends on good preparation and your ability to look after yourself. It's important everyone on the water has the right knowledge, experience and equipment. Always wear lifejackets and take two forms of waterproof communications equipment, such as a distress beacon, cellphone in a plastic bag, or VHF radio."
Beacons save lives, according to the spokesperson.
"If you are in a life-threatening situation and need to be rescued, activate your distress beacon and leave it turned on until help arrives."
They also urged boaties to always check the weather and have a plan B in case things go wrong.
Water Safety New Zealand CEO Jonty Mills reminded people the environment can change rapidly and can be unforgiving.
"People need to respect the water and make wise decisions. Stay within your limits, know the risks and take all necessary safety precautions."
TOP THREE SAFETY TIPS FOR BOATIES:
1. Take a registered distress beacon and waterproof ways to call for help.
Register your beacon at www.beacons.org.nz - it provides RCCNZ with crucial details that help them assist you faster.
VHF radios are a great option. A cellphone in a sealed bag is better than nothing.
Don't own a beacon? Rent one! See the list of rental outlets on the Beacons website.
2. Tell someone where you're going.
Keep Coastguard NZ updated. Every time you leave your home port, contact the Coastguard NZ Communications Centre either on the Coastguard marine VHF channel for your area or on your cell phone via *500. You can also file a trip report via the Coastguard app.
3. Prepare, prepare, prepare
Make sure your boat's good to go and you have enough lifejackets on board. For Coastguard's full level 2 checklist, including how-to videos, go to boatiesbestmate.nz.
Know the weather - look at the marine forecasts. If it's looking dicey – stay home or change your plans.