He had come out of the Presbyterian church, which is across the street from the crash site, to get sound equipment for the Sunday service, when the sound of a helicopter coming low and loud through the thick marine layer prompted him to look up.

“I couldn’t see anything, not even a silhouette,” he said as he looked across the street where the steep mountainside rose, the grassy slope now littered with wreckage. “My first thought was what in the world is a helicopter doing out here in this fog?”

Low cloud layers are common in the area, but on Sunday the fog was so thick it came nearly to the ground and made visibility so low, church members said, that they had trouble driving.

For about 20 seconds on Sunday morning, Daehlin followed the sound of the helicopter as it swept over the church parking lot and south toward the crest of the Santa Monica Mountains. It sounded even and normal, but, he said, “it sounded too low.”

“It sounded almost like the pilot was hovering, trying to find his way,” said Daehlin, who said his father was a pilot. He added “I had a sinking feeling in my stomach, and I was saying, ‘Get some altitude.’”

Then he heard a loud thump and the crack of what sounded like fiberglass, and all sound from the engines stopped.

He called 911 and directed fire crews to the hillside. He could not see the crash because of the fog, but saw some smoke and heard several pops as the wreckage burned.