The family and two other adults were headed for Thanksgiving weekend in southeastern Arizona when the twin-engine plane traveling at 200 mph slammed into a sheer cliff in the mile-high Superstition Mountains an hour after sundown Wednesday, authorities said.
The aircraft exploded in flames, split apart and scattered burning debris.
"No one could have survived that crash," Pinal County Sheriff Paul Babeu said Thursday.
The body of one child was recovered and dozens of sheriff's search and rescue personnel worked Thursday to recover the remains of the other victims.
Babeu said he personally notified the mother late Wednesday. The woman, who is divorced from the children's father, is also a pilot.
"This is their entire family -- it's terrible," Babeu said. "Our hearts go out to the mom and the (families) of all the crash victims. We have had so many people that are working this day, and we just want to support them and embrace them and try to bring closure to this tragedy."
By coincidence, a search and rescue team was in the craggy, jutting mountains searching for three missing teenagers Wednesday evening and saw the explosion, Babeu said. The searchers found the teens, then went up the mountain to try to reach the crash site.
Ten deputies who spent the night on the mountain were relieved by 10 more early Thursday. They and dozens of volunteers began searching the crash site at first light. Video from news helicopters Thursday morning showed the wreckage strewn at the bottom of a blackened cliff.
"This is not a rescue mission, but that of recovery," Babeu said.
The dead included pilot Shawn Perry, 39, his two sons and his daughter, Babeu said. Morgan Perry, 9, Logan Perry, 8, and Luke Perry, 6, lived with their mother in the community of Gold Canyon in Pinal County. Their father lived in Safford in southeastern Arizona and owned a small aviation business there.
He had flown to the Phoenix suburb of Mesa with another pilot who co-owned the company and a company mechanic to pick up the children for Thanksgiving. The plane was headed back to Safford when it crashed.
The other pilot was identified as Russell Hardy, 31, of Thatcher, Ariz., and the mechanic was Joseph Hardwick, 22, of Safford.
There was no word on what caused the crash but the sheriff said there was no indication the plane was in distress or that the pilot had radioed controllers about any problem.
The Federal Aviation Administration and the National Transportation Safety Board are investigating.
It was very dark at the time, and the plane missed clearing the peak by only several hundred feet. The aircraft crashed about 40 miles east of downtown Phoenix around 6:30 p.m. Wednesday, authorities said.
Some witnesses told Phoenix-area television stations they heard a plane trying to rev its engines to climb higher before apparently hitting the mountains.
The mountains are filled with steep canyons, soaring rocky outcroppings and reach an elevation of about 5,000 feet at the highest point.
Part of the recovery operation was in such dangerous terrain that only teams well trained in using ropes could maneuver, Babeu said.
"Regular deputies and even myself would not go into this exact area," he said.
The plane was a Rockwell AC-690A and was registered to Ponderosa Aviation Inc. in Safford, which Babeu said was co-owned by Perry.