An Air New Zealand pilot of 39 years, Colin Glasgow, told the court the pilot received warnings no pilot should ever hear.
"Pilots will fly their entire career and not hear these warnings," Mr Glasgow, a prosecution witness, said.
He said "a number of elements" were breached in the flight, which placed the aircraft at undue risk.
A witness to the departure said he had never seen an aircraft take off at that angle before.
Robert Clark, a mechanic, was in his vehicle in a street above Lake Wakatipu when he saw the plane fly over.
"I'd never seen one take off at that angle before, quite honestly," Mr Clark said. "Normally, they come out and climb, but this one sort of didn't."
Thirty seconds after take-off, a Fire Rescue Service member called the control tower asking: "How big are his gonads?"
Defence counsel Matthew Muir told the court in March the pilot was "probably the absolute top of the tree in terms of aircraft qualifications".
The defence case will start before Judge Kevin Phillips today.