Unfortunately without a black box or cockpit voice reporter, investigators will have a difficult time knowing what caused a small plane to crash in Montana Sunday killing 14 people, half of them children.
What investigators do know so far is that the small single-engine turboprop plane, a Pilatus PC-12, was overloaded.
Federal aviation officials say the plane was not certified to carry commercial passengers.
It had 14 on board but was designed to have a total of 11, including two pilots. In all, seven children and seven adults were killed. Earlier reports were that the plane had 17 onboard.
The Swiss-made plane is configured to seat 9 or 10 people, but the New York Times reports this aircraft was said to have seating for 12.
The plane left the city of Redlands, east of Los Angeles Sunday morning. It flew to Vacaville, about 50 miles north of San Francisco and stayed less than an hour before flying onto Oroville, where it picked up a group of people.
Tom Hagler, owner of Table Mountain Aviation, tells USA Today he saw a group of a dozen children — ages 6 to 10 — and four adults at Oroville Municipal Airport.
"A lot of really cute kids," he said. They were apparently going for a ski vacation.
They boarded for the 2.5 hour flight to Bozeman, Montana. For some reason the plane diverted northwest to Butte, about 85 miles northwest of Bozeman.
About 500 feet short of the runway it made a sharp turn to the left, then went into a nose-dive into the ground at the end of a cemetery.
Many are wondering how many were not buckled in, which would throw off the center of gravity in a plane likely already overloaded with ski equipment. Sharp turns could have caused bodies to fly and an unstable aircraft.
Mark Rosenker, acting chairman of the National Transportation Safety Board (NTSB), told ABC News, "It will take us a while to understand. We have to get the weights of all the passengers; we have to get the weight of the fuel, all of the luggage."
Some of the luggage is retrievable to determine weight measurements. Small children were said to be onboard and were likely sitting on their parents lap.
Before the plane crashed, the pilot gave no indication to air traffic controllers of any difficulty when he requested permission to divert to Butte.
A witness says the plane jerked to the left before it took a nose-dive. Another witness says he thought he was watching a stunt plane because of the many turns the small plane was making. The plane seemed to stall upon the final approach and go into a spin at a low altitude.
A family of five from St. Helena, California, Dr. Erin Jacobson and his wife, Amy were among the victims. Their three children were preschoolers.
There was no radar a the Butte airport so the pilot would use visual flight rules and switch to radio frequency to determine if other aircraft were in the area.
The pilot is unidentified and it’s not known if there was more than one pilot onboard. But the plane was registered to Eagle Cap Leasing Inc. in Enterprise, Oregon. That company’s president is a pilot.
Last month a commuter plane crashed into a house in a Buffalo, N.Y. suburb killing all 49 people onboard. Before that, it had been two years since there were any fatalities on a commercial airliner in the U.S. #