Roundel of China National Aviation Corporation (1942-1949): A white "中" in blue circle.
<a href="//commons.wikimedia.org/wiki/User:Ericmetro" title="User:Ericmetro">Ericmetro</a>
Own work  using: <a rel="nofollow" class="external autonumber" href="http://www.cnac.org/dc401c.jpg">[1]</a> and <a rel="nofollow" class="external autonumber" href="https://www.timetableimages.com/i-bc/cn4706a.jpg">[2]</a>