The two musicians were passengers on a Learjet that crashed shortly after takeoff about midnight Friday in Columbia, S.C. They had performed earlier that night at a college event, along with former Jane's Addiction singer Perry Farrell and Gavin DeGraw, who were not onboard the plane.
Killed in the crash were pilot Sarah Lemmon, 31; co-pilot James Bland, 52; security guard Charles Still, 25; and Chris Baker, 29, Barker's personal assistant -- who caught the flight to Los Angeles to be with his pregnant wife. A cause of the crash hasn't been determined.
Barker has burns on his torso and legs, while DJ AM (real name: Adam Goldstein) was burned on his arm and head. Both are in critical but stable condition at a burn center in Augusta, Ga.
"Since both Barker and Goldstein are in overall good health and didn't suffer from any other crash-related complications, a full recovery is expected," the burn center's Dr. Fred Mullins tells People.
Barker, who currently plays with the band (+44) and performs with DJ AM under the name TRVSDJAM, also starred in the MTV series "Meet the Barkers" with then-wife Shanna Moakler. Moakler flew to Georgia Saturday to be with her ex-husband; they have two children together.
Goldstein and Richie dated for several years and were engaged for most of 2005 before breaking off their relationship. He was later linked to Mandy Moore; they broke up in 2007.