HMS Gannet's duty observer, Lieutenant Angela Lewis said: "Conditions were extremely challenging.
"Sea spray from the waves was being whipped up to a height of about 60ft in places and we were in the hover at about 80ft, so it was quite nerve-wracking."
The Royal Navy Sea King helicopter from HMS Gannet in Prestwick, Ayrshire, was first on the scene.
A Royal Navy spokeswoman said the crew were forced to leave one aircrewman on board the stricken boat following a problem with the rescue helicopter's winch.
The team rescued five stranded crew members before the aircraft developed a defect and Petty Officer Mike Henson was left on board with two remaining seamen. It was Petty Officer Henson's first shift as a qualified search and rescue aircrewman.
All three were later rescued by an RAF helicopter.
For more coverage of the striken cargo ship visit ITV Wales.
An operation to refloat the stricken cargo ship which ran aground in rough seas is due to begin.
Salvage and counter pollution experts are expected to begin assessing the damage to the 82-metre long vessel after it hit rocks near Colwyn Bay in North Wales.
The Marine and Coastguard Agency said the cargo ship was in one piece following the incident, but there are growing concerns that it could begin to leak some of the 40,000 litres of fuel it is carrying.
To hear more about the dramatic rescue from the coastguard visit ITV Wales.
Llandudno Lifeboat's crew have thanked the emergency services involved in the rescue.
All seven Polish crew members on the cargo vessel aground have been rescued and taken to safety.
Ray Carson from the Holyhead Coastguard agency has spoken about the successful operation to rescue all crew members from cargo ship that ran aground in North Wales.
The Maritime and Coastguard Agency have confirmed that all seven Polish crew members on the German cargo vessel which has run aground have all been rescued and taken to safety.
The rescue was completed at 0100BST.
More updates and video on the cargo ship run aground in North Wales can be found on the ITV Wales website.
A spokesman for the Marine and Coastguard Agency said:
The 82-metre long ship, registered in Antigua and Barbuda, was carrying a load of stone.