His sister, Dottie Pollock, lives next door to Hess' home in Waynesboro. She said Friday night that Hess had been visiting in Waynesboro since Sunday and was on his way back to Pensacola when the crash occurred.
Hess joined the Navy as a pilot. That took him to Pensacola, where he completed flight training and later became a flight instructor, according to a biography supplied by the family.
In the 1970s, he served two terms as a member of the Florida legislature.
He was a successful businessman, founding a radio station, a television station and two banks, said longtime friend John Appleyard of Pensacola.
Sgt. Thornnie Rouse said Hess had stopped briefly at the Hagerstown Regional Airport between 10:10 and 10:20 a.m. and then took off. Shortly afterward, he radioed the airport he was turning back because there was heavy fog and he was disoriented, Rouse said during a press conference at the Clear Spring Library.
About 90 minutes later, state police were notified a construction crew working near the bottom of the mountain had seen a low-flying plane and then heard a sound that could have been a crash, Rouse said.
A heavy veil of fog covered the top of the mountain Friday morning. About .81 inches of rain fell in Washington County from 4 to 10 a.m., according to Hagerstown Weather Observer Greg Keefer's Web site.
Rouse said the weather was so bad state police refused to send their helicopter to the crash site.
About 40 fire and rescue workers used an access road to reach the top of the mountain and search for the plane, said Joe Kroboth, Washington County Emergency Services director.
"It was steep and rough terrain," Kroboth said.
Around 12:25 p.m., the rescue workers found the plane smashed into a pile of rocks, he said. Police said the crash site was about 100 yards from the top of the mountainside.
The aircraft sheared trees and set the dense brush on fire. Firefighters drove brush trucks and a tanker truck up to the top of the mountain and lowered hoses to the crash site, Kroboth said. They worked until at least 2:30 p.m. to put out the fire, he said.
The plane caught fire on impact and it was clear to rescuers the pilot was dead, Kroboth said. He said the morning's heavy rain may have helped prevent the fire from spreading.
The crash site was about 200 yards from an access road but the slope was steep and the ground was slick from the morning rain. There were no paths to the site.
Police and rescue crews used a rope to rappel down the mountain, police said.
The plane was identified as a 1964 Beechcraft S35 registered to William Heatherington of Gulf Breeze, Fla.
Three officials from the Federal Aviation Administration arrived at 3:18 p.m. to investigate the crash. Brian Rayner, air safety investigator with the National Transportation Safety Board, is also investigating.
Rayner could not say Friday night what caused the crash, but expected to file a preliminary report next week. Small planes like the one in the crash do not carry black boxes with flight data, he said.
A livery arrived to pick up the pilot's remains, which will be taken to Baltimore for autopsy, said Washington County Deputy Medical Examiner Dr. Howard Weeks.
Civil Air Patrol members were expected to monitor the site during the weekend until the wreckage could be recovered, state police said.
Clear Spring Volunteer Fire Department, Hancock Fire Co., Maugansville Goodwill Volunteer Fire Co., Longmeadow Volunteer Fire Department, Clear Spring Ambulance Club and Hancock Rescue Squad responded.
Friday's plane crash occurred nearly on the one-year anniversary of a plane crash on South Mountain in Washington County in which the pilot and two passengers died. A Crownsville, Md., couple and a male friend from Severn, Md., were returning to Maryland after a trip to Indiana when they crashed into the mountainside on the Appalachian Trail.
Staff writers Andrew Schotz, Laura Ernde and Scott Butki contributed to this story.