The National Transportation Safety Board has released their preliminary report on the flight that presumably crashed into the Atlantic Ocean about 100 nautical miles east of Charleston.
The plane departed around 10:45 a.m. from a private runway in Andrews, Georgetown County, on Oct. 25, 2018. It was bound for Governor's Harbor Airport in the Bahamas.
The Piper PA31T crossed over the coastline and climbed towards its assigned altitude, 25,000 feet, at an appropriate climb rate of 500 feet per minute, the report states. When the plane reached 24,300 feet, "the pilot made a garbled radio transmission indicating that he was diverting to CHS (Charleston)."
The plane, still on course, began descending at about 1000 fpm. "About 23 seconds later, after several air traffic control requests to repeat the transmission, the pilot replied, 'we're descending,'" according to the NTSB report.
About 15 seconds after that, at an altitude of 23,500 feet, the plane made a sharp left turn and its descent rate increased to more than 4000 fpm. Another 25 seconds went by, and the radar data altitude parameter went invalid, with a last-reported altitude of 21,500 feet.
Then, roughly 35 seconds later, the pilot made his last transmission.
"Emergency! Emergency! Five five five papa mike."
"Five five five papa mike" indicates the planes tail number, "N555PM."
The last radar position was recorded at 11:19 a.m., about three miles northeast of the plane's original course, or roughly 100 nautical miles east of Charleston.
The Federal Aviation Administration issued an Alert Notice and the U.S. Coast Guard began a search effort.
A search airplane reported an oil sheen on the surface of the water near the last-known coordinates, but neither the plane nor its wreckage was ever located.
The Coast Guard suspended their search two days later.
The NTSB report states the plane had undergone its annual inspection back in September, and the pilot's most recent medical certificate was issued in March. At the time, the pilot reported nearly 2800 flying hours.
The weather records revealed mild weather conditions, but there was an Airmen's Meteorological Information Advisory for moderate turbulence in effect for the region at that time.
The FAA has not identified the pilot or the four occupants of the plane, however, the Post and Courier reported two of the passengers were from South Carolina: Jamie Mitchum, Jr., 58, and Joseph Wayne Allbritton, Jr., 34.