Julie Ann Wright, 50, of Circleville, Kan., was a passenger in the Mercer Transportation rig driven by her boyfriend, James R. Miller, also of Circleville, when she apparently opened the door of the cab around 8:55 a.m. and fell to the roadway, Capt. Jimmy Sexton of Dougherty County Police said.
Wright, whose name was initially withheld pending notification of her family, sustained fatal injuries in the fall, Sexton said.
The tractor-trailer was traveling west at more than 50 miles per hour on the 3000 block of Sylvester Road when Wright opened the door and stepped out, he said.
Approaching vehicles immediately stopped and attempted to render aid to Wright, but there was nothing they could do, he said.
Albany police, firefighters and Georgia Troopers helped divert traffic as evidence from the scene was examined.
Wright and her long-time boyfriend were en route to Marine Corps Logistics Base-Albany to pick up a load, police said.