As investigators scoured the field where a Soviet-era military jet crashed just a day before, planes from the Quad-City Air Show performed overhead Sunday.

The day began before 8 a.m. for Davenport police and Scott County investigators trying to find out why the L-39 military jet plummeted to the ground, killing Glenn Smith, 59, of Frisco, Texas.

Their job Sunday was to catalog each piece of debris they could find, and then secure it for delivery to a hangar at the Davenport Municipal Airport.

Davenport Police Major Don Schaeffer said that while the cause could turn out to be a mechanical problem or pilot error, “We don’t see anything of that nature at this time.”

Aaron Sauer, senior air safety investigator for the National Transportation Safety Board, based in Chicago, said that numerous pieces of the aircraft have been recovered at the secured crash site.

Sauer said they eventually will reconstruct the plane to help determine the cause of the crash.

“We are in charge of the site now. We are doing it remotely, but I am in constant communications of what needs to be done,” he said. “We will recover every piece of that airplane (and) lay out the wreckage to help us see if there are any issues with the aircraft.

He said investigators also will look at the plane’s maintenance records and do an autopsy and toxicology report on Smith’s remains recovered from the site. They also will look at his medical history.

Investigators and evidence technicians as well as members of the Volunteers in Police Service, or VIPS, met at the crash site, an alfalfa field off Northwest Boulevard just north of Interstate 80.

Just as the team was starting to work, a squadron of planes flew over the crash site in the “missing man” formation, a tribute to the downed pilot.

They spent seven hours cataloging more than 400 pieces of the plane. Each piece was photographed where it lay and given an identification tag before it was removed and placed in an evidence bin, Schaeffer said.

Each piece had been marked with an orange flag Saturday during early stages of the investigation. The sea of orange flags slowly disappeared from the field as the day wore on.

Davenport’s crash investigators were on hand to detail the crash scene using their crime-scene mapping equipment.

A plane also few over the site early Sunday to collect aerial photographs of the wreckage.

Schaeffer said there were thousands of pieces of debris in the spot where the plane augured in. A Davenport Fire Department tower truck was brought in so that investigators could photograph and map the site of impact.

Davenport Public Works employees then were sent in to collect the remainder of the wreckage with a backhoe. That wreckage included the tail section that could be seen near the crash site. A large piece of an engine also was recovered.

Schaeffer said that all of the pieces of the plane that have been collected have been taken to a hangar at the Davenport Municipal Airport.

Crash witnesses Robert and Barbara Poell of Davenport said they couldn’t go back to the air show Sunday.

“I can’t get the image out of my head,” Barbara Poell said from her home Sunday. “It was disturbing to see something like that. I didn’t want to have anything to do with planes today.”

She works for Cobham, a Davenport-based company that makes parts for jet planes. She said the crash hit her personally. 

Her husband said the couple left right after the accident. “It took the enjoyment out, seeing something like that,” Robert Poell said.

Throughout the day, people drove by the crash site. Most spent a minute or two looking and then drove away.

Others parked along the street leading to the crash site because it offered a great view of the planes as they came over.

Sauer said while there is not the so-called “black box” found on commercial airlines, “There may be other devices that contain memory. We are not sure what other instruments there are on board. But we will obtain any memory that we can.”

Four FAA inspectors are on the scene, Sauer said, two who already were monitoring the air show and two who responded from Des Moines.

“We have had a busy weekend, unfortunately (with other aircraft crashes), so the decision was made for us to sit tight.”

Many spectators shared videos and photographs of the accident.

“All that evidence will help us try to determine what exactly happened there,” Sauer said.

He referred to an air-race crash last year in Reno, Nev., that killed 11 and injured 66. Recently, the NTSB determined that the crash resulted from aircraft vibrations that caused a tail-wing part to fail. He said it was videos and photographs from spectators that “was instrumental in finding the cause of that accident.”

Brian Wellner contributed to this report.