Incident Overview
A helicopter departed Burbank Airport after the pilot requested and received a special VFR clearance to exit the Class C airspace. The aircraft proceeded southbound and subsequently collided with high voltage transmission wires at an altitude of approximately 150 ft above ground level.
Weather Conditions
At the time of departure, the airport's prevailing weather was reported as 300 ft broken clouds, visibility 2-1/2 miles with fog and light rain. Ground witnesses later described the weather in the area as having rain showers, cloud obscuration, and visibility of only 1/4 mile. They reported that the helicopter was barely distinguishable under those conditions.
Flight Path and Radar Data
Radar data indicated that after departure, the helicopter did not climb above 300 ft AGL. The aircraft continued southbound until impacting the power lines.
Sequence of Events
The helicopter became entangled with a second set of wires, leading to separation of the main rotor assembly. The aircraft then plunged to the ground.
Pilot Actions
Before departure, the pilot received the current ATIS. However, he did not obtain a weather briefing from the Flight Service Station (FSS) nor file a flight plan.