"He's coming for us.. we're both gonna die!"
— Brad to Jill, shortly before his death.
Brad Vickers was in charge of chemical protection and served as the S.T.A.R.S. Alpha Team's helicopter pilot. Brad wasn't much of a fighter, and it is not mentioned as to whether or not he had served in any combat capacity before his recruitment into the S.T.A.R.S unit. He was known to lose his nerve under pressure, leading to the nickname "Chickenheart" amongst his comrades. His hometown was Delucia.
"The police aren't trained for this kind of situation! What could they do?!?"
— Brad commenting upon the futility of the RPD's defensive measures.
On July 24, 1998, the S.T.A.R.S. Alpha team was sent into the Arklay Mountains to investigate the disappearance of S.T.A.R.S. Bravo team, whom the RPD had lost radio contact with the previous night. After spotting and confirming Bravo team's crashed helicopter, Alpha team landed near the wreckage and proceeded to investigate. Brad then panicked and abandoned his teammates in the Raccoon Forest after witnessing the death of fellow S.T.A.R.S. member Joseph Frost. Upon regaining his composure, Brad made multiple attempts to re-establish contact with his S.T.A.R.S. teammates whilst flying over the Arklay Mountains and mansion, however, he was unable to receive messages from the damaged radio carried by the survivors. He later assisted them in destroying the Tyrant (T-002 Model) by dropping a Rocket Launcher from the chopper, and then rescued Chris, Jill, Rebecca and Barry moments before the Spencer Mansion exploded.
Shortly after the incident, in response to pressure from Umbrella, Police Chief Brian Irons had S.T.A.R.S. disbanded. Fearing for his job, Brad sided with his employer over the decision.
During the Raccoon City Destruction Incident, Brad was spotted by "the pursuer" and had been on the run for days throughout the city attempting to evade it. He was presumabley infected with the t-Virus after being bitten by zombies that he had encountered earlier on September 28. Eventually, Jill caught up with Brad at Bar Jack, who was fending off a zombie and bitten in the process. He then warned her of the presence of a "monster" in the city, and its hunt for S.T.A.R.S. members.
Later, he arrived at the RPD precinct and encountered Jill, once again, at the front gate. As he approached Jill to speak with her, he was cornered and killed by the Nemesis. Minutes later, and possibly due to his previous encounters and exposure to the t-Virus, he presumabley reanimated as a zombie, as his corpse is nowhere to be found when Jill exits the RPD precinct not long after.
On September 29, the following day, a zombified Brad was spotted by Claire Redfield who, whilst making her way to the police station, killed him, finally putting him to rest.