The National Transportation Safety Board released a report about a helicopter crash in north Scottsdale that many find stunning.
The cause of the Feb. 14, 2010 crash, according to the report, was likely a 5-year-old girl who was on board.
The girl was the daughter of helicopter's owner, valley businessman Thomas J. Stewart.
He, his wife, daughter, brother-in-law and the pilot all died in the crash.
The findings are part of a probable cause report, released by the NTSB Wednesday, but despite the findings, some say the cause of the crash will become a battle.
NTSB investigators say Stewart let his daughter sit on his lap in the co-pilot's seat during the flight which crashed near Cave Creek.
"Having a little girl sit in your lap while flying, that's an absolute no no. I wouldn't do it personally not to say it
doesn't happen. It happens all the time," said ASU associate professor Michael Pearson.
Investigators say it's "highly likely" the child inadvertently stepped on the "collective," putting the chopper in the full down position. They found the pilot quickly pulled up.
"What the collective does is change angle of blades if you do it too rapidly..will cause the rotor to flex," explained Pearson. "What I think they're saying is it caused the rotor to flex..that it came down and hit the tail."
The NTSB says the pilot's lack of control in the cockpit contributed to the crash.
The report found Stewart, who wasn't licensed to fly helicopters, would fly it anyway.
Some felt the hired pilot was intimidated by him and therefore did not insist proper procedures be followed.
A lawyer for the pilot's family, who is suing over the crash, disputes the report. He blames a faulty rotor blade.
With millions of dollars at stake, only a jury will likely determine where the fault lies.
"Oh yeah, it'll be a battle. Both sides hire top experts in the field in order to determine what happened," said Pearson.
The NTSB's probable cause finding is released as a safety measure -- it isn't allowed to be presented in court.
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The Associated Press contributed to this report.