Harry Butler took part in Australia’s first Aerial Derby, which was held in Adelaide on September 8th, 1920. The other two contestants were Captain Frank McNamara, V.C., and Lt. F.S Briggs, both of the R.A.A.F. Again it was to promote an Australian Peace Loan, and the race was over a distance of about 30 kilometres. The course went from Northfield to Port Adelaide, thence to Henley beach, and finished over Adelaide GPO clock tower.

The Derby was flown in the lunch hour to give the greatest number of people an opportunity to watch the event.