What happened
On September 30, 2012, an Agusta 109E EMS helicopter, registration N144CF, crashed approximately 4.4 miles south of Eastland Airport in Eastland, Texas. The flight, operated by CareFlite, was a repositioning mission to pick up a patient.
While the initial portion of the flight from Granbury Airport was conducted in visual meteorological conditions, the weather deteriorated as the aircraft approached Eastland. The pilot initiated a climb to 4,000 feet MSL to communicate with air traffic control and attempted to activate an IFR flight plan. Upon engaging the autopilot in altitude hold mode, the helicopter abruptly pitched down 9 and began spinning.
The pilot identified a disagreement between the pilot and co-pilot attitude director indicators, deactivated the autopilot, and attempted an unusual attitude recovery using the backup vertical reference gyro. Despite these efforts, the aircraft continued a rapid descent through the clouds. The helicopter eventually broke through the cloud base near the ground, touched down in a level attitude, bounced, and skidded to a stop in an open field. All three crew members—the pilot, a flight nurse, and a flight paramedic—sustained 3 serious injuries.
The investigation
Investigators examined the wreckage and the flight control systems, finding that all control links from the cockpit to the star mixing lever were intact, though several control rods had fractured due to overload during the impact. The engines and transmission showed no pre-impact mechanical anomalies.
While the autopilot, gyros, and servo components were examined, the solid-state components could not be tested due to damage from the crash. A review of the maintenance history for N144CF revealed several previous reports of uncommanded flight control anomalies, including uncommanded rolls and oscillations, though maintenance technicians had been unable to duplicate these issues during inspections.
Findings
- The helicopter experienced an in-flight upset immediately after the pilot selected the autopilot's altitude hold mode.
- The exact cause of the reported in-flight control anomaly could not be determined.
- The pilot delayed transitioning from VFR to IFR flight before encountering instrument meteorological conditions (IMC).
- The transition into IMC may have contributed to spatial disorientation during the recovery attempt.