Based at Prince Henry Hospital since 1987, the Westpac Life Saver Rescue Helicopter Service is the largest non-profit search and rescue and aeromedical retrieval service in Australia.

Founded in 1973 by Surf Life Saving Australia, the service has carried out more than 50,000 flights ranging from patient transfers to search and rescue missions. Its aircraft and trained medical and operational crews respond quickly and effectively to emergencies threatening the life, health and safety of people through medical emergency, illness, natural disaster, accidents or mishap.

In 1987 the Surf Lifesaving Association established a permanent base for the helicopter rescue service at Prince Henry Hospital, with a landing pad located on the  oval, adjacent to the Accident and Emergency Department.

While the hospital is no longer on the site, the Westpac Rescue Helicopter base remains and continues to respond to emergencies along the NSW coast. 

Reference: Wikipedia