I did not understand the principle. This was a nice new twin-boom RPV, but where were the VTOL rotors?
Your link explains: "4.5.2Rotafix
This concept, developed by A. Kisovec, is based on a side-by-side configuration where
either two-bladed or single-bladed rotors are located at the tips of wings with dihedrals. When
the rotor is stopped in flight, the advancing blades form a spenwise extension of the wing,
while the retreating blades in the two-bladed, or counterweight in the single-bladed configurations
are retracted into the fixed-wing structure. In this way, the rotorcraft is converted into
a high aspect ratio aeroplane. Although, in principle, this concept can be used for transport aircraft, the present
efforts of Kisovac are chiefly directed toward RPV applications (Figure 4.85)."
OK, the wing tips are single-bladed rotors. Incredible! Thanks Hesham, I never saw a twin-boomer like that!