FOUNTAIN HILLS, AZ — The National Transportation Safety Board has released its report on a deadly helicopter crash near Fountain Hills.
Court documents show the chopper had a history of trouble.
The NTSB report found that the helicopter's flight was taken to "evaluate developmental main rotor blades that had been installed on the helicopter."
The report also said, "The test flight legs consisted of multiple autorotations at maximum gross weight involving a simulated loss of engine power. The accident flight was the last test flight of the main rotor blades before the certification process."
A witness reportedly saw the helicopter falling from the sky after hearing a loud boom. She used her phone to record a portion of the crash.
Parts of the helicopter were scattered around a mile-long area.
Two people killed in the crash were identified as contract experimental test pilot Rucie Moore and Van Horn Aviation engineering manager Stephen Estes.