Enable BiasT on RTL-SDR v3 before Dump-FA/Piaware start

Infact it is the other way round. If you scroll to bottom of the rtl-sdr . com page, under Credits you will find link to this thread. The method in rtl-sdr . com is based on @obj’s method given in post #2 of this thread.

You’ll get better results with lower gain, at least for airplanes flying close by and low.
In the second post of the thread linked below there is some practical advice on setting gain:
Thoughts on optimizing gain

With your LNA/dongle combination try 28 as a start.

Here is a short summary how to change the gain depending on your installation:
For Beginners - How to Set / Change Gain

Thank you. I will experiment a bit with that.