What you need first is airplane model, wingspan around 4 meters, 2 or 4 stroke gasoline engine up to 8 HP, equipped with decent reliable remote control with all fail safe functions you can get.
This bird should be able for MTOW around 40 kg. On top of that you can use one of the ingenious Micropilot Canada devices (
MicroPilot - World Leader in Professional UAS Autopilots | Home Page) for nice, smooth, stable and safe fully autonomous flight. Down-link (FPV feed and telemetry), you can choose 5.8 GHz 10Watt transmitter.
Up-link booster no more than 10 Watt with Yagi antenna.
A lot of knowledge and big balls.
There is no limit what you can do with this technology. Only limitation is governments around the globe and their regulations.
From 1993 up to 1996 I made like 50 flights over 50 km, the longest one was 82 km, equipped with 1 GHz /1 Watt FM video transmitter as down-link and 72 MHz / 25 Watt up-link for commands.
Stable flight established with accelerometer and altitude hold function with magnetometer dial. No telemetry, no GPS - navigation via good old fashion maps in paper.
With today's technology - piece of cake....
But for those flights you need altitude of more than 1.000 meters to gain VLOS all the time.