Helistar director Bruce Lilburn, 40, appeared for sentence in Rotorua District Court yesterday for operating an aircraft causing unnecessary danger.
Lilburn told the court he should have made two trips with the four passengers, rather than one, The Dominion Post reported.
A Transport Accident Investigation Commission inquiry found the helicopter was 18kg overweight on take-off and climbed only 20 to 30 metres before losing altitude and crashing on December 11, 2006.
Lilburn said he underestimated the unpredictable nature of the alpine environment when he took off.
Three Conservation Department staff and Helistar co-pilot Adrian Petherbridge were seriously injured in the crash.
After helping pull the passengers away from the helicopter, Lilburn, who had a broken ankle, climbed an ice wall above the lake to get cellphone coverage to summon help.
Just before take-off Lilburn was asked if he wanted to make two trips into the crater to pick up passengers. He allegedly replied that he would "give it a go" with one trip.
Outside court, Lilburn, who pleaded guilty in September at a pre-trial hearing, said he accepted responsibility for the accident.
"I believed on the day I was right with the decision I took but, in hindsight, I made a terrible mistake."
He accepted he should have made two trips to take the passengers off the mountain.
Lilburn was an experienced pilot, having made more than 200 flights to Mt Ruapehu during 12 years of commercial flying.
However, Judge Phillip Cooper said Lilburn had taken on a high level of unnecessary danger and risk to his passengers.
He sentenced Lilburn to 200 hours' community work, ordered him to pay $10,000 reparation to the four victims, and disqualified from flying for six months, beginning in February.
