Below is from The Pacific: General Aviation and Questions forum including typos.
CIRCUMNAVIGATION
While I agree that a true circumnavigation would include the crossing of all meridians and the equator, the rules applied by the Federation Aeronautique Internationale(F.A.I.) for validating aerial circumnavigations are:
"Fora powered aircraft to officially circumnavigate the world it must cross allmeridians in one direction, travel a distance of at least 36,787.559 km (thelength of the Tropic of Cancer), and complete the journey at the point ofdeparture. Each leg must commence at the exact point where the previousfinished off. There is no requirement that it cross the Equator or touchantipodal points.
TheF.A.I. o has a different (less stringent) set of rules for inflatable craft,such as balloons and blimps, which are at the mercy of winds and jet streams."
Good effort by the Russian and I see that the first Solar powered flight is about completed.
It seem that the age of adventure is not over yet.