Note 1.— For the purposes of document 8643, micro-/ultra-light aircraft are those aircraft types with a maximum take-off mass of 454 kg/1 000 lb or less and a stalling speed not greater than 35 kt.
Note 2.— Micro-/ultra-light helicopters and gyrocopters are those helicopters or gyrocopters with a maximum certified take-off mass of 454 kg/1 000 lb or less.
Designators to be used for unmanned aircraft (UA) having a maximum take-off mass of 454 kg/1 000 lb or less.
UA which is not capable of hover or vertical flight and needs to be in horizontal motion to sustain flight.
FFLO(forward flight lift only)
UA which is capable of vertical flight and hover
VFHC(vertical flight and hover capability)
Note.— Tilt-rotor or tilt-wing UA, should use FFLO or VFHC depending on the aircraft capabilities for the particular operation.