RAD-73 "Eisenfalke"

This is RAD-73 “Eisenfalke” by Reichenbach Aero Dynamics.
This aircraft was built as a technology demonstrator for vertical takeoff and landing using tiltrotors, and its airframe was later repurposed for the RAD-98 ring-wing aircraft.

Controls:
AG1 Engines
AG2 VTOL
AG3 Level Flight
AG4~6 No function
AG7 Air Brake
AG8 Landing Gear
AG9 Fixation Leg
AG10 RCS

Caution:
All gears and legs deploy/retract automatically.
Movement in VTOL mode is somewhat difficult (as this aircraft is not primarily designed to move like a helicopter).
When transitioning from level flight to VTOL mode, air brakes will automatically apply to decelerate until speed reaches 80m/s. Keep the engine throttle at 0% during this period. (If absolutely necessary, you may proceed without reducing to 0% until safety is ensured.)

Addendum: Reichenbach AeroDynamics appears to have uncovered evidence that Schwarzflug Corporation misappropriated their engine design. Reichenbach intends to reduce the compensation amount in exchange for Schwarzflug's blueprints of the enhanced engine design.