Airshow general manager Ed Taylor said he was thrilled with the report, which showed spending was up by $4million on the previous show.
Those who came to the region specifically for the event spent a total of $23,621,631, he said.
Others who were coming to the region anyway but also attended the airshow spent another $18,551,916.
The report was compiled by Research First Ltd from a survey of 1239 people.
Mr Taylor declined to provide a copy of the report to the Otago Daily Times.
He said 97% of those attending the show gave it a positive rating, compared with 90% in 2016.
"We're especially pleased with the high satisfaction levels.
"This is something our whole team works so hard on - making sure that the flying displays are world-class but also that everything else about the airshow, right down to the toilet facilities, are top-notch."
One example of where the show did not get it "quite right" was in the number of food outlets (about 50) at lunchtime.
There were more food outlets on site "but obviously not quite enough and this meant some lengthy queues at peak times".
Of the international visitors surveyed, 28% stayed in bed and breakfast, farm stay, homestay or Airbnb accommodation, 18% in motels and 13% in both hotels and holiday homes.
There was strong growth in the average length of stay, which was up from 3.5 nights in 2016 to 4.1 nights this year.
Total bed nights for the show was 154,582, up 26% on 2016.
Mr Taylor said he was heartened by the 91% who gave the show a positive safety rating.
"Safety is obviously our single biggest focus area."