Hello. I am having an issue with a pro plus dongle where I am getting good results
I have noticed a similar effect when light aircraft and helicopters fly within about 1km and under 1500’.
The close aircraft stops reporting for 5 or 6 seconds and has a signal strength of about -1 to -1.4 and the Age list on Skyview suddenly shows greater than zero for 2/3 to 3/4 of the aircraft in the list. (usually only about 10%)
I think the local aircraft is overloading the front end of the amplifier or receiver and it is blocking most signals until it turns or flies further away.
In my case it can be fixed by reducing the Gain of the Pro Stick Plus from the default -10 to 45 (or less) and restarting Piaware
SSH to the Pi and log in.
type piaware-config rtlsdr-gain 48
type sudo systemctl restart dump1090-fa
Changing the gain will affect your maximum range and for me it changes the point where I lose signal for planes landing at the airport about 20km away.
What pi and dongle are you using? I had a lot of trouble getting my zero W to work properly and found the answer was to use a USB extension cable to get the pi and dongle 50-80cm apart. It wasn’t behaving like yours though.
In addition to SweetPea11’s suggestion, I have found the gain optimisation script useful. I did change the time period between gain settings to 5 sec though as I found 62 secs was too long. The planes in my range moved too much in 17 mins (which is how long it takes each cycle) for me to get any really useful data. The script will leave the gain set at whatever the last test setting was (i.e. if it runs through 5 times, it’ll be set on 20.7)