Park dispatch received a call just after 7 a.m. on March 15th reporting a seriously injured bike rider on Crater Road at the 8,500-foot level. Rangers responded and were on scene in ten minutes. A 44-year-old female rider with a commercially led bicycle tour made it through the apex of a turn, but then crossed the center line and crashed into rocks. Tour leaders immediately called for assistance and began first aid. Rangers assessed the patient, determined that her injuries were serious, and called for an ambulance. She sustained major head trauma in the accident even though she was wearing a helmet. Ambulance personnel subsequently called for an air evacuation, and a helicopter landed at Hosmer Grove at the 7,000-foot level . The woman was driven there, loaded on board and flown to a hospital. Her condition was not known at the time of the report. The investigation continues.