A 20-year-old man is in a critical condition after falling 10 metres from a tree he was in and rolling down a bank.
The man landed on his head at Orere Point, at the top of the Firth of Thames, at about 2am on Saturday morning.
Auckland Rescue Helicopter Trust communications manager Lincoln Davies said the man was unconscious when the Mechanics Bay Westpac 2 Red Chopper crew met the St John Ambulance at a nearby field to transport him to Auckland City Hospital.
The ambulance was en route to hospital when the man's condition deteriorated and it called for helicopter assistance, a St John spokesman confirmed.
The paramedics carried out a rapid sequence intubation to assist the patient's breathing.
The early morning call-out to Orere Point marked the first of the second-busiest day ever for the Auckland Rescue Helicopter Trust, which responded to nine calls on Saturday.
The high demand for the Auckland and Coromandel rescue helicopters was on par with New Year's Day this year where crew also responded to 9 calls. The busiest day so far for the trust was New Year's day 2017 when its rescue helicopters responded to 10 jobs.
The helicopter crews also rescued a man in his 40s who jumped 3.6m and flipped over his handlebars while biking in Woodhill Forest, northwest of Auckland. He landed on his face and was knocked out for about 20 minutes, sustaining multiple injuries. He was flown to Auckland City Hospital in a serious condition.
A woman in her 30s had to be winched out of a remote area on Mt Karangahake near Karangahake Gorge after slipping and breaking her ankle.
The rescue helicopters also responded to two medical complaints among older patients and one girl who had an allergic reaction to nuts and another who reacted to a wasp sting.