When riding a jet plane, assuming the time is right and you’re seated in the right seat, you can see the plane’s shadow on the ground. It must be moving as fast as a .45 cal slug. Would a person notice the shadow when it passes over him? Once I was walking alone inside a stadium. Then there was a sudden “blink” in my surroundings, like there was a momentary blink of the sun’s rays. No, it’s not low-lying clouds changing the sun’s brightness. I can actually see cloud shadows on the ground. They (clouds) don’t move that fast. Could it have been an airplane’s shadow?
Sure. I’ve had one pass over me any number of times.
My house is beneath a flight path. Depending on the time of year, and the sunniness of the weather, I notice the shadows of planes flicker past several times a week, sometimes many in a day.
It does happen, but the airplane needs to be at a fairly low altitude for it to eclipse the sun. At cruise altitude, it would just be a small dot moving across the sun, and you wouldn’t even notice the dimming caused by it.
(Or to put it another way, at high altitude the airplane only creates a penumbra.)