At 10:03 a.m. Sept. 11, 2001, United Airlines Flight 93 hit the ground near Shanksville in rural Somerset County at 575 mph.

The plane had dropped from 3,500 feet, and slammed into the grassy field so hard the shock waves tore insulation from a building in the area and shook a high school 12 miles away.The resulting fireball rolled over hundreds of acres of forest; the smoke lingered for two days.The 44 people aboard were, for the most part, obliterated.Small bits of their bodies were caught in trees, and more were found to have been driven through the windows of a cabin some 800 feet away, Somerset County coroner Wallace E. Miller told those attending the sixth annual forensic symposium, held Saturday at the Simon Kramer Institute, New Philadelphia.The conference was organized by Schuylkill County coroner Dr. David Moylan.It's been 16 years since terrorists, 17 Saudi Arabians, one Egyptian and one Lebanese, directed by al-Qaida leader Osama bin Laden, hijacked four occupied American jetliners.Loaded with enough fuel for cross-country flights, the terrorists deliberately crashed two planes into the World Trade Center in New York City, and one into the Pentagon.The fourth plane, Flight 93, is believed to have been intended to be flown into the nation's Capitol in Washington, D.C. It crashed into the field after passengers attempted to thwart the hijackers.A total of 2,977 people were killed in the attacks.The crash changed Miller's life.He told those attending the conference he quickly learned to delegate responsibilities, make sure everything was accurately documented, and coordinate a mass casualty situation.Identifying the bodies was extraordinarily difficult; most had been vaporized by the impact and intense heat. Identifiable pieces were blown over acres.Penn State arborists climbed the tall trees to recover remains."Cadaver dogs were overwhelmed," he said. "The odor of death was everywhere.""It was an overwhelming situation," Miller said.He said his teams managed to recover only 8 percent of the bodies, none intact.Miller sent one casket home to a victim's family holding only a quarter-sized piece of skull.Because the remains were too minute to identify, they were buried at the site, now a national memorial.Miller considers the site a cemetery.Also speaking was Washington County Coroner S. Timothy Warco, who talked about preparing death scene investigations.Warco said that when he is called to death scenes, he always makes sure that any pets on the premises are taken care of, either placed with relatives or turned over to an animal shelter.Warco, a longtime emergency medical technician, praised volunteer firefighters and ambulance crews for their help at death scenes.Dauphin County Coroner Graham Hetrick spoke about determining cause and manner of death in cold cases.He cited methods used in resolving the case of retired pastor Arthur "A.B." Schirmer, convicted of killing his first and second wives in 1999 and 2008, respectively.Hetrick also addressed the current opioid epidemic."We're asking the wrong questions," he said.The question is not what to do about it, he said. Rather, it's why are the most free, most comfortable and rich people in history "suffering so much pain - and it is spiritual pain - that they need to anesthetize themselves," Hetrick said.Other speakers included former state trooper James Nettles, who spoke about the origins of heroin and exploring overdose death scenes; Christopher Wolfe, who spoke about the "body farm" at the University of Texas; K-9 Specialist Don Wilcox, who spoke about search and rescue operations with the help of search dog Alex; and Moylan and Dr. Mary Pascucci, who spoke about the radiological and pathologic correlation of virtual and traditional autopsies.Guests also observed a virtual autopsy, done via CT scan.Hetrick stars in "The Coroner: I Speak for the Dead" on Investigation Discovery.