AFD R-3 and HR-3 along with the ARS were dispatched to the Appalachia Straight to a MVC with entrapment.  Upon arrival Captain Scotty Sharrett assumed command.  The vehicle was extremely unstable and had to be stabilzied before rescurers could begin extrication.  The vehicle was attached by cables at both ends of the vehicle to prevent rollover into the river.  The vehicle had left US 23 and flpped down the Powell River embankment where it rested against a small unstable tree.  Once AFD stabilzed and cut away the B-Post and removed the passenger side doors extrication begin.  The patient was extricated and transferred to ARS personnel for transport to the Appalachia High School where Wings Air Rescue awaited arrival of the patient.  Due to the extent of impact and patient complaint of injuries the patient was flown to Holston Valley Medical Center's Level 1 Trauma Center.