Two skydivers jumped from a plane shortly before it crashed into a line of trees.
The pilot of the Cessna aircraft also walked away without injuries.
It is believed the plane lost engine power as it was preparing to land at Parakai, near Helensville, around 12.15pm yesterday.
The Civil Aviation Authority is investigating the crash, and communications manager Mike Richards said it was possible the trees slowed the plane as it came down.
"Probably it reduced the velocity of the aircraft, and reduced the force of impact, so that was good luck," he said.