Investigation Summary
The flight departed Concord Pavilion at 21:45 local time following a Huey Lewis and the News concert. The pilot, Steve Kahn, had requested and received a special VFR clearance to transit Buchanan Field airspace despite visibility of only 0.5 miles and heavy rain. The aircraft, a Bell 206B (serial number 1391), was likely being navigated via pilotage. Witnesses reported seeing the helicopter flying parallel to California State Route 37 at an altitude of approximately 200 feet AGL, just below the cloud base, in deteriorating conditions. The NTSB found that the pilot had significant geographic knowledge of the area but chose to continue VFR flight into instrument meteorological conditions (IMC) at an unsafe altitude. The impact occurred near the northern edge of San Pablo Bay, where the helicopter struck the top of a 223-foot Pacific Gas and Electric Co. transmission tower located roughly 150 feet south of the highway. The force of the collision and subsequent explosion caused the wreckage to become 'welded' to the tower, requiring a large crane for recovery days later. The accident caused a power surge that interrupted the concert at the Pavilion and left 23,000 homes without electricity.
Final Conclusions
The NTSB determined the probable cause was the pilot's intentional flight into known adverse weather, continued flight into instrument meteorological conditions, and improper altitude. Contributing factors included low ceilings, poor visibility, and restricted visual lookout.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Held airline transport, flight instructor, and commercial certificates. Although highly experienced, he was not rated to fly helicopters on instruments.
Systems & Failure Modes
Visual Flight Rules (VFR)
A set of regulations under which a pilot operates an aircraft in weather conditions generally clear enough to allow the pilot to see where the aircraft is going.
Special VFR Clearance
An ATC authorization allowing a pilot to operate within the lateral boundaries of controlled airspace in weather conditions less than the basic VFR minima.
Interesting Facts
- 01The pilot was warned by air traffic controllers that VFR flight was not recommended due to weather.
- 02Weather at takeoff included a 200-foot ceiling, 0.5-mile visibility, and heavy rain.
- 03The high-voltage tower was clearly marked on the area sectional aeronautical chart.
- 04The helicopter remained impaled on the tower until NTSB investigators could examine it.
- 05The accident killed promoter Bill Graham, his companion Melissa Gold, and pilot Steve Kahn.
Safety Actions & Advisories
NTSB Weather Briefing Emphasis
The investigation highlighted the critical importance of pilots adhering to weather briefings that recommend against VFR flight. The NTSB reiterated that 'VFR not recommended' is a formal advisory that should be treated with extreme caution, especially in areas with known obstructions like high-voltage transmission lines.