Some passengers on the ill-fated hot-air balloon may have been electrocuted or killed by the "intense heat" of a fire generated upon contact with a 33,000-volt powerline - before they had even hit the ground, an expert says.
Balloon pilot Lance Robert Hopping and 10 passengers died after their Early Morning Balloons hot-air balloon burst into flames on Saturday.
The balloon hit or became trapped in powerlines, causing a spark or arcing in the basket which then caught fire.
Two of the passengers jumped or fell from the balloon before it shot up into sky, then quickly plunged to the ground.
The exact circumstances of what caused the tragedy, how everyone died and whether anything could have been done differently to save lives is still under investigation.
However, a power engineer said the line that supplies such intense energy could generate heat greater than 2000degC.
"The intense heat upon contact with the powerline and the reduced weight in the balloon because of the two people jumping off would have turned the balloon into a rocket," said the engineer.
"It is possible that most of those in the basket would have been electrocuted and may have died upon contact with the ruptured powerline." Powerco yesterday would not comment, saying the matter was now under police investigation.
The powerlines supplied power to 3800 homes in the area, which experienced a supply cut for several hours following the incident.
One of the questions that is expected to be looked at during the investigation is whether the outcome would have been any different had two of the passengers not exited the balloon shortly before it leapt skywards then plunged to the ground.
Balloon experts say one of the key safety messages hot-air ballooning passengers are given is to never exit the basket unless the pilot says so - because the consequences of doing so can be incredibly dangerous for everyone on board.
Balloon Aviation Association president Martyn Stacey said he did not want to speculate on what, if any difference, the couple's exit could have made.
But he said all balloon rides started with safety checks on all balloon equipment and a safety briefing for the passengers which included a key message about always remaining inside the basket.
"That is one of the most important rules, once you are in the basket you stay in the basket no matter what ... that is a standard brief that everyone should be saying to passengers in every balloon ride," Mr Stacey said.
"It is critical because you imagine losing 100kg and you have got a thing that weighs nothing - all of a sudden it will go racing up in the sky. If you imagine losing two passengers, which happened on Saturday, the pilot's got no control - he's lost 120kg and away he goes," he said.
