The contact owned a 2019 Subaru Crosstrek. The contact stated while her husband was driving at 25-30 MPH downhill, the tractor trailer before him slowed down at a curve. The contact's husband depressed the brake pedal but it failed to respond and the vehicle accelerated unintendedly, causing the vehicle to fall into a ditch where it bounced and hit the rear of a trailer, then bounced back into the embankment. The passenger's side and driver's side roof rail air bags deployed. The frontal air bags failed to deploy. The emergency units transported the contact and her husband to the hospital where it was diagnosed that the contact had sustained a compression fracture in her back. Her husband did not sustain any injuries. The occupant of the trailer did not sustain any injuries. A police report was filed. The vehicle was towed to a tow lot where it was totaled. The dealer was not notified of the failure. The manufacturer was notified of the failure and a case was opened. The contact was awaiting a call back from the manufacturer. The failure mileage was approximately 31,200.