A rescue co-ordination centre spokesman said the alpine team were dropped in the area, which was being buffeted by strong winds and shrouded in low cloud, and walked towards the beacon.
They discovered a sole tramper who was suffering from exhaustion.
He was walked out with the team to a lower point where the helicopter was able to fly them out of the mountains.
The spokesman said the successful operation had proved the worth of carrying a personal emergency beacon into the wilderness.
"It has potentially saved his life," said the spokesman.
The tramper was taken to his car, which was parked at the start of the Routeburn Track, and was now heading home, he said.