30 years ago I saw a UFO, Glendale CA

(Late Evening) I was 15-16 yrs old at the time, I had witnessed a bright light in the distance approaching from the west. Initially I assumed it was an aircraft, such as a plane or helicopter, as they were routine sights to see, it was flying low altitude <1000ft. I continued to observe the light gradually come towards our direction, as it approached closer I soon realized that 1) There are NO blinking/strobing lights, that you would otherwise see on a typical aircraft (green and red). 2) There was absolutely NO Sound emitting from the craft, engine from a turbo-prop or whirring from blades would make a definite sound that would be recognizable.
I exclaimed, "What is that?" to my cousin who was next to me, who was also observing, the light seemed to show the silhouette of a saucer, at this moment the craft flew at an incredible speed (5k mph?), in a short zig-zag pattern before shooting off towards the East, all without a sound! It was gone in a blink of an eye.