What happened
During a nighttime flight departing from Santa Monica, the pilot of a Mitsubishi MU-2 requested clearance through the TRACON at 6,500 feet. Due to a failure in the automated VFR handoff process to the ARTCC, radar service was terminated. The pilot subsequently contacted the Santa Barbara Flight Service Station, which was not equipped with radar. At the time of the contact, the pilot was informed of deteriorating weather conditions, including fog and low cloud ceilings.
Without a filed flight plan or prior clearance, the pilot initiated a VOR runway 2el approach. While inbound, the Mitsubishi MU-2 descended through the cloud layer and converged with a Fairchild SA227 that was executing an IFR approach to the same airport. An ARTCC controller alerted the FSS specialist to the potential conflict, and both flight crews were notified of each other's positions. Although the pilot of the Mitsubishi MU-2 reported being approximately 7 to 8 miles out on the approach, they did not respond to inquiries regarding whether the aircraft was operating in IMC.
Radar tracking indicated that the Mitsubishi MU-2 collided with the Fairchild SA227 at an altitude of 400 feet. Following the collision, the pilot of the Mitsubishi MU-2 attempted a left turn over the shoreline, appearing to maneuver for spacing, but the aircraft entered a descent and crashed into the ocean. The accident resulted in four fatalities.
Findings
Post-accident examination of the wreckage revealed that the master caution and battery over-temperature lights were illuminated at the time of impact. The collision occurred while the Mitsubishi MU-2 was operating without radar service and without established clearance for the approach.