Two lifelong Sonoma County residents, one the owner of a nationally known Santa Rosa engineering firm and the other the owner of a family carpentry company and a pilot, died while on a Jeep ride in Cazadero.

Don Charles of Forestville and Leslie Meline of Santa Rosa apparently died Sunday but the wreckage was not found until Tuesday evening.

Charles, 53, owned DH Charles Engineering, with offices in Santa Rosa and San Diego. The company builds temporary structures and support equipment for contractors and has completed more than 8,000 projects in eight years, including current scaffolds on the Golden Gate Bridge and work on the Bay Bridge retrofit, said partner Jasper Calcara.

Meline, also 53, was an avid pilot and flew privately, commercially and was instrument-rated, said her son, Gabe Meline.

She also helped run the family finish carpentry company.

The two had known each other since elementary school and had been in touch recently while helping plan a Montgomery High School reunion for the class of 1971.

Sunday, Meline was invited by Charles to see his family?s Cazadero ranch. The accident occurred as the two were on a Jeep ride, the CHP said.

Charles was driving up a steep, unimproved dirt roadway on his family?s remote property, about three miles north of Bohan Dillon Road, the CHP said.

The Jeep, which was in 2-wheel drive at the time, apparently lost traction and slid backward. The Jeep left the road and plunged down the hill about 500 feet before stopping.

The two died in the crash.

Family members filed missing persons reports early in the week. They also began combing the area and found them in the wreckage Tuesday evening.