Yannick Chatachvilly (34) had been made aware of the ice and frost on the wings of the Cessna 177 by his passengers before take-off on August 15, 2017.
He brushed some off with his hand and said the rest would "blow off" naturally, according to the court summary of facts.
The engine failed on take off and crashed moments later, coming down on grass to the side of the runway.
The plane's three passengers sustained minor injuries - cuts, bruises and sprains. One was partially ejected and the plane suffered significant damage.
Chatachvilly admitted the ice and frost, affecting airflow over the surface of the wing, could have contributed to the severity of the crash.
He appeared in the Queenstown District Court yesterday afternoon for sentencing on one charge of operating the aircraft in a manner which caused unnecessary danger to three people.
Judge John Brandts-Giesen had previously declined his application for a discharge without conviction.
Defence counsel Tim Mackenzie said it was case of "low culpability" in terms of dangerous flying offences; "... one act of failing to clear ice and frost by a well-intentioned young pilot" who did not have much experience in flying such aircraft.
"He accepts it came down harder than it might otherwise have."
Chatachvilly is an A320/21-rated pilot in Europe. He had re-sat 21 examinations in New Zealand and was applying for a job in the industry when he was charged.
Mr Mackenzie said this was a "huge mitigating factor". Chatachvilly had dedicated money and time to his career but would now carry a dangerous flying conviction with him "for the rest of his life".
Judge Brandts-Giesen regarded the offending "at the modest end of dangerous".
"This was a significant mistake by you," Judge Brandts-Giesen said. "Your conduct was somewhat cavalier and not of the standard one would expect of a commercial pilot with passengers on-board."
It was the pilot's responsibility to ensure the aircraft could perform as well as possible, whatever the circumstances, Judge Brandts-Giesen said.
However, he appreciated the impact the conviction would have on Chatachvilly's life, particularly in terms of finding work.
"The court has great sympathy for that and recognises professional people make mistakes ..." but denunciation and deterrent were important.
Chatachvilly had paid $1000 for the principal victim to go on a course to address the psychological impact of the crash with regards to future flying.
