In the UK Microlight aircraft are limited to 450kg MAUW, this is both a restriction of the licence conditions of the pilot and also a safety figure for the max loading of the airframe structure. IF the SAME aircraft is certified as a GA aircraft it is allowed to fly at a higher MAUW as the safety margins for a GA aircraft are calculated using a lower factor. Same aircraft, different max weights. Just an observation.........
Rans6..........