WASHINGTON — Wally Boeck's final flight ended, fatally and inexplicably, near the southern shores of Lake Camanche.
The retired Marine Corps aviator hadn't planned to reach the Calaveras County reservoir. On a cool November afternoon in 2008, he had simply wanted to test some new landing gear on the lovingly restored 1946 plane he dubbed Maximus.
Instead, for reasons federal investigators have now concluded will remain forever uncertain, Boeck collapsed several minutes after taking off from Rancho Murieta Airport. For the next hour, his Globe Swift GC-1A flew on and on while a pilot and videographer in a chase plane watched helplessly.
"We could see no one sitting up at the controls," video camera operator Frank Falusi told investigators. "Instead, we saw a sleek, beautiful airplane, high in the sky, engine running, but with no one at the controls."
Falusi and chase pilot David Clinchy figured Boeck was slumped over into the passenger seat, but they had to peel away when their own aircraft ran low on fuel, about three miles from Lake Camanche. The next morning, Calaveras County Sheriff's Department search teams found the wreckage of Boeck's plane.
Boeck was 67, a former head of the California Student Aid Commission. His was one of 32 fatal general aviation crashes in California in 2008. Four remain under investigation.
Now, after more than a year of analysis, National Transportation Safety Board investigators have concluded the probable cause of Boeck's crash was "the pilot's incapacitation during cruise for unknown reasons."
Sudden cardiac arrest seems a fair guess, but the National Transportation Safety Board did not publicly speculate in the final report quietly issued March 3. The Calaveras County coroner found some narrowing of Boeck's cardiac arteries but no evidence of a clot. The coroner could not determine if Boeck was alive when his plane hit the ground.
Still, documents from the federal investigation into the Nov. 6, 2008 crash provide vivid details about the protracted mid-air drama above the San Joaquin Valley. They also portray a memorable character who could rebuild a plane as well as fly it.
"No task was too laborious, uncomfortable or unimportant for him," Falusi told investigators. "Wally's attitude was that if it needed to be done, it needed to be done right."
Boeck had retired from the Marine Corps as a lieutenant colonel, after 20 years of service that included two tours in Vietnam. He led a local chapter of the Experimental Aircraft Association and encouraged fledgling pilots through the Junior Eagles program.
He had spent two years rebuilding the two-seat Globe Swift. The Nov. 6 flight was only his second in the restored aircraft.
Falusi and Clinchy knew almost immediately that something was awry after taking off in tandem shortly after 4 p.m. They watched Boeck start a slow left turn, and then the nose of his plane dipped down.
"Wally's aircraft continued to bank left and then the nose dropped into a steep dive," Clinchy told investigators. "I radioed to Wally, 'What are you doing, where are you going?' There was no response."
Boeck's plane proceeded on a gyrating elliptical course, plunging down to 1,900 feet and then climbing back up to 3,800 feet before dropping down again. Clinchy repeatedly tried to raise him on the radio, but heard nothing. Clinchy tried to approach for hand signals, but Boeck's plane was flying too erratically.
The two planes kept turning on an unplanned course, one following the other. This went on for an hour. The sun set, and Clinchy was losing sight of his friend's plane. Finally, he had to leave.
"I had a false hope that when I lost sight of him he had returned to the airport and landed," Clinchy told investigators. "I returned to the airport; he was not there."