Investigators had to improvise at Somerset County crash site
The United Flight 93 crash site near Shanksville is hallowed ground, the final resting place of Sept. 11 victims who fought their attackers.
But the 70-acre field in rural Somerset County presented the FBI with one of its largest crime scenes. With evidence in trees, a lake and underground, investigators had to improvise to handle the site.
"There was no textbook for any of this," said Special Agent Andrea Dammann, who coordinated the agency's evidence gathering.
Since Flight 93 crashed in an open field, instead of buildings as in New York and Washington, it offered the best hope of quickly yielding evidence about the terrorist attacks and preparing the United States for the possibility of another attack.
Investigators found mostly fragments, virtually inscrutable from afar but critical to the painstaking effort to identify the plane's 40 passengers and crew and reconstruct the act carried out by four al-Qaida hijackers on the Newark, N.J.-to-San Francisco flight.
They found a credit card, receipts, identification cards, a box cutter and other items the terrorists carried. Some evidence became exhibits in the prosecution of al-Qaida conspirator Zacarias Moussaoui, who was sentenced to life in prison in 2006.
Flight 93 hit the earth at 10:03 a.m. at 580 mph, the last of four hijacked planes to crash, according to The 9/11 Report by the National Commission on Terrorist Attacks Upon the United States.
"Initially, our thought was: Where was the plane• There didn't appear to be a plane anywhere," Dammann said. "We had a little bit of fire that was put out the first day. Otherwise, we really had a clear site."
Mike Soohy, a retired FBI supervisory special agent, said he worked to get approval overnight to spend "hundreds of thousands of dollars" to have PennDOT pave a long, asphalt road so heavy equipment could get to the crash site.
To retrieve wreckage and evidence stuck in a stand of trees, Dammann called in arborists from Penn State University, who climbed them. Specially trained divers flew in to explore Indian Lake when crews looked for the voice and flight-data recorders. Later, crews drained the lake to collect evidence from its bottom.
Investigators found the data boxes in a crater created by the plane's impact. One ended up 26 feet below the surface.
More than 100 FBI agents from offices as far away as Chicago and Knoxville, Tenn., worked at the scene for about two weeks beside dozens of officers from other federal agencies and state police.
Moving quickly but diligently raised their chances of finding human remains that would yield DNA to identify those on the plane.
The largest identifiable body part the team recovered was an arm, Dammann said. Among the smallest was a tooth, embedded in a tree trunk. They recovered enough DNA evidence to identify everyone aboard.
Normally, investigators would fret over disturbing a single tire track at a crime scene, said Special Agent David Hedges, but the task was so monumental the FBI brought in backhoe and skid loader operators to scoop debris and spread it across the field for examination.
Among the most important finds was a checklist reminding the terrorists to blend in when boarding planes and instructing them to "shave their beards," Soohy said. Investigators found a similar checklist in New York, showing the coordination of the attacks, he said.
Personal items such as driver's licenses, tickets, passports and even a red bandana materialized.
"What I thought was amazing was how much of it came out intact," said Patrick McGlennon, an FBI supervisory senior resident agent.
Investigators found an undamaged metal badge and assumed a law enforcement agent accidentally dropped it. A closer look revealed it belonged to passenger Richard Guadagno, 38, of Eureka, Calif., who received law enforcement training through the U.S. Fish and Wildlife Service.
"It did not have a mark on it," Dammann said.
Dammann turned over the personal items to United in March 2002 so the airline could give them to victims' families. Plane parts weren't considered evidence because investigators knew the cause of the crash. They kept the wreckage in Dumpsters until giving it to United.
State police kept away people not authorized to be there. They developed a wristband system, McGlennon said, changing the color of the bands daily. During the investigation, only one person, a New York Times reporter, tried to enter the site without permission.
Conspiracy theorists began spreading rumors soon after the crash that the government shot down the plane.
"We brought in people from the explosives unit and had them swab the plane parts for explosive residue," Dammann said. "They did not find any explosive residue."
Soohy spoke to witnesses who saw the plane go down.
"They said it wasn't burning, it wasn't smoking, and it didn't have a hole in it," he said.