A final determination of a single-engine plane crash Monday in North Bryan County that killed three people could take up to a year, according to the National Transportation Safety Board.

John Brannen, a senior air safety investigator with the federal agency, said he should have a preliminary report done within a week after returning to his Chicago office, but that the final report detailing the probable cause of the crash could take six months to a year.

Killed in the crash were William Cocke, 42, and Catherine Cocke, 39, of Savannah, along with the pilot of the chartered plane that was flying the couple from Savannah to Cobb County. The couple leaves behind five children ranging in age from 10 months to 13 years. The pilot has been identified as Randy Hunter of Tyrone, Ga.

Bryan County Emergency Services Chief Freddy Howell said the FAA contacted his agency around 9:30 a.m. saying the plane was flying at an altitude of about 300 feet before it crashed.

The wreckage of the aircraft was found at 11:18 a.m. when it was spotted by a Coast Guard helicopter. Searchers included Bryan County Emergency Services, Bryan County Sheriff's Office, Effingham County Sheriff's Office and Effingham County Emergency Services. Emergency personnel used ATVs to get to the aircraft. It was located off of Eldora and Croft roads.

Brannen said the last radio contact the pilot had with air traffic control at the Savannah/Hilton Head International Airport was at 8:39 a.m. Monday when he indicated he was having engine problems and would attempt to return to the airport.

The plane crashed in a heavily wooded area near a cotton field in North Bryan near the Effingham County line. Brannen said he is unsure if the pilot was attempting to land in the field or not.

“We are gathering the voice recordings and radar data right now,” he said. “We’ve also located the maintenance records for the plane.”

Because of the location of the crash, Brannen said a company out of Griffin, Ga., has been contacted to remove the plane.

“We can’t do a whole lot of examination on the scene because of where it’s at,” he said.

Once the plane is extracted, the engine will be sent to the manufacturer’s headquarters in Mobile, Ala., for a thorough examination.

Brannen said the final report will take into account “man, machine and environment,” including whether or not Monday’s high winds and rain from a tropical depression off the coast played a part.

Howell said about 40 to 50 personnel were involved in the search, which included two boats on the Ogeechee River. There was no fire from the crash, so Howell said searchers could not locate it by following black smoke. Some media are reporting that the pilot radioed that he was having engine trouble and that he was attempting to return to Savannah.

Authorities have closed off the area.

"It's very heavily wooded," Howell said. "Georgia Forestry cut a path for us to access the site."

The Bryan County Coroner’s Office arrived at the scene about 12:30 p.m. Monday. Officials said all three occupants of the plane died on impact.

Howell said Hunter, the pilot, owned Hunter Aviation out of Peachtree City. He was chartered to fly to Savannah to take the Cockes to Cobb County. Officials are unsure if Hunter flew the plane to Savannah earlier Monday morning or Sunday.

Howell said the Beechcraft Bonanza plane bearing the tail identification of N87RY was chartered from Falcon Field near Atlanta. Brannen said the plane was manufactured in 1994 and its records will be looked at as well as the pilot’s flight log.

A woman driving a vehicle with a Chatham County license plate showed up at the Bryan County Emergency Services staging site at the Georgia Forestry office on Eldora Road around 1 p.m. Monday. She was visibly upset and crying. Howell later identified her as a nanny for the Cocke family.

Howell asked the public to pray for the victims as well as the first responders involved.

“The rescue people are just as traumatized about a situation like this as the general public is,” Howell said of those who located the crash and found the bodies.

Jeff Whitten contributed to this report.