This is a variant of World War 2: The Struggle for Europe and Asia with some twists. Bombers/Attack aircraft cannot destroy land units, instead disrupting them, loosing combat ability next round. Cavalry units are included. Convoy sites must have freighters on them to carry goods. On a roll of six (using 1d6), units must break off combat and retreat/return to base. Japan has Floatplane Fighter-Bombers. And there are some others.