Runkles was supposed to be driving that day but disliked the task, causing him to switch with another person, Audrey Runkles said.
She talked to her son Wednesday.
"He sounded great. He sounded like his old self again," Audrey Runkles said, adding that he seemed to be relaxed because he was no longer in a dangerous area, but rather was at Landstuhl Regional Medical Center in Germany.
Brad Runkles was one semester away from finishing college when he learned in December that he was to be deployed to Iraq. Although he previously attended West Virginia University, he plans to finish his last semester at Shepherd University. He is majoring in accounting and business administration, his mother said.
Runkles joined the Air Guard to help pay for his tuition and because it offered an opportunity to travel around the world, his mother said.
Runkles' father formerly served as a member of the Air Guard.
Both Runkles and Brown knew of the job's dangers. "I think that was the fourth time that a bomb went off close to them," Audrey Runkles said. "They knew they were in danger but they wouldn't tell us, the mothers."
Runkles said she knew her son was hauling supplies, but did not know he was serving as part of an Army convoy on the front lines.
The device exploded after the convoy left Balad Air Base, which is about 40 miles north of Baghdad. Sencindiver said he was not sure what was being hauled or the cargo's final destination, but said the convoy was traveling north on a main supply line.
Runkles said her son was in the front passenger seat while Brown was serving as the gunner and was in the back of the truck.
Runkles and Brown are two of five members of the 167th Airlift Wing who are traveling as members of Army convoys, he said.
Sencindiver said he knows of only six local members of the 167th stationed in Iraq, but said others have been deployed overseas to areas that are not hostile, such as Germany.
Since news of Runkles' injuries spread, many friends have called to find out how he's doing, his mother said.
"That's all I've been doing the last two days, is answering the phone," Audrey Runkles said.