Crash of a Piper PA-31-325 Navajo C/R in Orinda: 5 killed

Before the accident, witnesses observed the aircraft circling in a valley beneath a low cloud layer and below the surrounding hilltops. They estimated the ceiling was 400 feet obscured. Two witnesses said the aircraft entered clouds before it crashed. A 3rd witness, who was a pilot, said the aircraft was at a very low altitude when it approached rising/mountainous terrain; he said the aircraft then entered a steep climbing turn and stalled after making two complete turns. Impact occurred in a nose low, left wing down attitude. No preimpact mechanical problem was found. The FAA had issued the pilot a special 3rd class medical certificate after he had quintuple heart bypass surgery. He was reported to have gotten 'quite angry' before the flight, when 2 passengers were late. A pathologist believed the pilot's death may have been due to arteriosclerotic heart disease; however, this was not verified. The pilot did not have an instrument rating and no record of a preflight weather briefing was found. All five occupants were killed.