DEKALB COUNTY, Ga. -- The National Transportation Safety Board has published its preliminary report about the May 8 plane crash that killed four people.

According to a witness in the NTSB report, which was released early Tuesday morning, he was about 2,300 feet from the end of the runway when he noticed the plane was moving "extremely" slow and was only about "75-100 feet above ground level when it went over his head." The witness added the engine sounded "normal and despite the slow speed, the airplane was not wobbling left to right."

About two minutes after taking off, the pilot, 53-year-old Greg Byrd of Asheville, N.C., radioed the tower controller and said, "I'm having some problem climbing here." He then said, "We're going down here at the intersection," according to the report. That was Byrd's last transmission.

The plane Byrd was flying took off from DeKalb-Peachtree Airport at around 10:10 a.m. and went down moments later near the Peachtree Industrial Boulevard interchange. FAA spokeswoman Kathleen Bergen said the Piper PA-32 aircraft departed Runway 3 Left at PDK, then crashed about two miles away.

The single-engine Piper PA-32 aircraft was scheduled to land just before 11 a.m., CT in Oxford, Miss., according to FlightAware. It had arrived at PDK at about 9:15 a.m., from Asheville.

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Also on board the plane were Byrd's two sons, Phillip Byrd of Asheville and Christopher Byrd of Atlanta, along with Christopher's fiancee, Jackie Kulzer of Atlanta. The two Atlanta residents had boarded the plane at PDK. Also killed in the crash was a family dog.

They were on their way to the University of Mississippi's graduation ceremonies Saturday for Robert Byrd when the plane went down.

Emergency responders arrived at the scene about a minute after learning of the crash. DeKalb County Fire Capt. Eric Jackson confirmed the four deaths. No injuries were reported on the ground.

Witnesses said they saw the plane flying very close to the ground, then crash into the interstate median. They said it "exploded" and burst into flames on impact. Nobody on the ground was hurt, although the front of a large truck was brushed by the plane just before it hit the median.

"It looked like it was struggling. You could see him trying to get the nose of the plane up. It was edging up, and then it just dropped," said motorist Don McGhee, 48, who saw the aircraft nearly hit a traffic light pole near the highway on-ramp. "It was just a huge fire, just smoke and fire."

The plane had just refueled, said Eric Alleyne, an air safety investigator with the National Transportation Safety Board. He will be doing a flight reconstruction and expects to release a report on the crash in six months to a year.

The small plane does not have a black box, Alleyne said, only an emergency locator transmitter that was not needed. He does not yer know whether the pilot made any radio contact before the crash.

Truck driver Gerald Smith, who was traveling eastbound on I-285, says he slammed on his brakes, and the plane clipped his hood.

"If I would have stayed on the gas, it would have come in the passenger door," Smith said. The plane crashed into the median wall separating the east-and-westbound lanes in front of him, and not much was left of the plane after the flames were extinguished.

"It was quite remarkable, considering the amount of traffic on 285 at that time of day, it was not more tragic than it already is," DeKalb County Chief of Police Dr. Cedric Alexander said of the crash.

Representatives from Levett & Sons Funeral Home removed the victims' bodies from the scene.

DeKalb Fire and the police departments from Chamblee, Doraville and Dunwoody responded to the crash. Dr. Alexander said the National Transportation Safety Board will be involved in the investigation.

Officials from the NTSB said Friday that an investigation as to the cause of the crash could take up to a year to complete.

All lanes in both directions of I-285 were blocked at the scene for much of the day while federal aviation and transportation officials conducted their preliminary investigations. Westbound traffic resumed its normal flow by 4:30 p.m, while eastbound traffic was allowed to resume travel along the stretch of interstate by 6 p.m.