Australian Light Sport Aircraft category

Basic definition ¹:

• MTOW: 600 kg (1,323 lb) or 650 kg (1,433 lb) for an aircraft intended and configured for operation on water or 560 kg (1,235 lb) for a lighter-than-air aircraft.
• Stall speed in the landing configuration (Vso) of 45 kn (83 km/h) CAS.
• Maximum of two occupants, including the pilot.
• A fixed landing gear. A glider may have retractable landing gear. (For an aircraft intended for operation on water, a fixed or repositionable landing gear)
• A single, normally apirated engine fitted with a propeller.
• A non-pressurised cabin.
• If the aircraft is a glider a maximum never exceed speed (Vne) of 135 kn (250 km/h) CAS

References

[1] Ultralight aviation on wikipedia