 The G 109 was the first motor glider built using composite construction to be granted Federal Aviation Administration approval.The G109B was developed after series production of the G109A which itself followed a number of early prototypes with differing wing spans, configurations etc.The G109B addressed several issues learnt from operation of the earlier G109A which included improvements to power (95Hp up from 80Hp on the G109A), performance of the wings when wet, crosswind behaviour and limits and cockpit space.