Accident
The crew began their descent to Hollywood-Burbank Airport at night under marginal weather conditions with low clouds. Air traffic control instructed the crew to divert to Los Angeles International Airport for a safe ILS approach. While descending in darkness, the aircraft impacted the slope of Mount Puente, located two miles east of Whittier. The wreckage was discovered several hours later. All 29 occupants on board were killed.
Investigation
Investigators determined that the pilot voluntarily descended below the minimum altitude for which he was cleared and attempted an approach at an altitude too low to clear the terrain. Additional findings noted that Captain Lewis R. Powell served as command pilot on this flight and previous ones, contrary to the limitation imposed by his medical certificate, although he was aware that the restriction limited his flying activities to company check pilot duties only. Copilot Charles K. Waldron was properly certificated but exceeded flight time limitations prescribed under Section 42.48 of the Civil Air Regulations. The flight did not follow the ARTC approach clearance, descending considerably lower than the minimum altitude prescribed between the Riverside range and the Downey fan marker. Weather was clear until reaching the Puente Hills, which were clear on the east slope but in fog to the west. Conditions at Los Angeles International Airport were satisfactory for the ILS approach for which the flight had been cleared, but not for a visual approach.
Probable Cause
The board determined that the probable cause of this accident was the action of the pilot in voluntarily descending below the minimum altitude for which he was cleared, and attempting an approach at an altitude too low to clear the terrain.