I'm pleased to see I'm not the only one who misremembers. Hope I don't screw this up:
1978 San Diego: PSA 727-200 on base leg to SAN overtakes C-172 in pattern. All lost. The quiet cockpit below 10K feet is one result.
1986 Cerritos: AeroMexico DC9-30 on long final to LAX collides with Piper Cherokee, reportedly at 6,500 feet. All lost. TCAS is one result.
GB