At approximately 20:20hrs units were dispatched to the reported auto-pedestrian accident in the 800 block of FM1092. Upon arrival of Truck 21 and FBCEMS Medic 10 a female subject was found down in the roadway after being struck. Following a trauma assessment revealing significant head trauma a request for Memorial Herman Life Flight was made bringing Engine 22 (Parker) and Safety 21 (Magana) to the scene for the LZ. Upon arrival of Life Flight 5 patient care was transferred and upon safe departure of the aircraft all units returned to service. The accident is under investigation by the Texas Department of Public Safety (DPS).