The pilot and his wing - a smaller, more dynamic version of a paraglider - disappeared into the densely wooded hillside about 3pm after he turned sharply in mid-air and lost more altitude than he expected.

Another pilot, Matt Langlands, said the man was injured as he landed.

"As he went to turn he went too hard, [landing] on his bum," Mr Langlands said. "They suspect he's got a broken back, but he can wiggle his toes, so hopefully not."

The man, 25, remained conscious and breathing throughout his rescue, which was made complicated by the difficulty of the terrain.

Paramedics and personnel from multiple rescue agencies spent 30 minutes stabilising the man. He was secured and passed hand-over-hand along a 40 metre path cut clear with axes and saws.

The man was later transferred to an ambulance rescue helicopter and flown to St George Hospital.

Illawarra Ambulance district officer Terry Morrow said the man would be assessed for possible fractured vertebrae.