The initial report issued Wednesday detailed how Vella and the pilot were on a routine patrol over Newport Beach about 6:30 p.m. Feb. 19 when they responded to a dispatch of a fight. The two flew over the area of the scrum and turned on an infrared camera.
Vella spotted the group fighting "and the pilot began to maneuver the helicopter in a tighter right orbit while (Vella) relayed his observations over the police radio channel," according to the NTSB report.
Officers on the ground arrived as the helicopter continued orbiting about 500 feet above, according to the NTSB.
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"The pilot stated that he watched as ground patrol officers got out of their car and approached the group, who by this time had mostly dispersed," the NTSB reported. "He was concerned that one of the group was about to start fighting with an officer, and he slowed the helicopter to keep the camera aimed at the scene longer, so that they would not lose sight of it behind a building."
But, the NTSB reported, "Suddenly the helicopter yawed aggressively to the right, and he immediately applied full left foot pedal and forward cyclic to try and arrest the rotation, but there was no response.
The pilot continued to attempt to correct the helicopter, but it "began to progress into a spinning descent," the NTSB said.
Vella "transmitted over the police radio channel, 'We're having some mechanical issues right now,' followed by, 'we're going down, we're going down.'"
The helicopter's rotating "became more aggressive as" it plunged toward the ground and the pilot struggled to correct it, "which appeared to be partially effective, but did not stop the rotation," the NTSB said.
The pilot said "the engine was operating throughout, and his goal was to continue to fly the helicopter with the engine still running, rather than reducing power and performing an autorotation to a populated area,'' the NTSB said.
The darkness obscured the horizon and an accurate reference point, "but he could see the lights of houses approaching, and sensed impact was imminent, so he pulled the collective control in an effort to bleed off airspeed," the NTSB reported.
The helicopter slammed into the ocean "hard in a downward right rotation" on Vella's side, the NTSB reported.
"The pilot recalled a sudden smash and saw water and glass coming toward him as the canopy shattered," the NTSB reported. "He felt the rotor blades hitting the water, everything then stopped, and within a few seconds he was submerged."
The pilot managed to get the mouthpiece from his rescue air bottle to breathe as he released his seat harness and pushed his way out of the wreckage to swim to the surface, the NTSB said. Onlookers helped pull him toward a boat, the NTSB said.