I am lucky (?) enough to have aircraft occasionally pass directly over my location - although usually at some reasonable altitude like 5000 ft.
The blue dot is me and that is a Boeing 777.
I have noticed that these passes include a little low-frequency transient near the start.
here is a close-up of the low frequency wave - it is just one pulse:
It has occurred to me that this may be a “bow wave” from the plane.
I wonder if anyone else has seen the same?
The plane was at 4500 feet.