During the lengthy trial in March and September last year, the Civil Aviation Authority alleged the pilot, then 54, took off at 5.25pm, 11 minutes after the rules stipulated it was safe to do so at that time of year. That, compounded by low cloud and high-cross winds, meant that a prudent and responsible pilot would have left the plane grounded.
The prosecution case centred on the idea that if there was an engine failure during or immediately after take-off, the plane - carrying 70 passengers - would not have been able to make it safely out of the mountainous basin and on to another airport.
In his 130-page judgment, Judge Phillips found the pilot did not apply the degree of care and attention a reasonable and prudent pilot would have exercised.
Gunn had 30 years' experience flying in and out of Queenstown.
It will take the 55-year-old 17 months to get a new licence, having been stood down for two-and-a-half years while the case was before the court.
Prior to the incident Gunn's commercial career comprised 16,043 hours' total flying time, of which 6000 hours were spent flying a Boeing 737.
