When the two sailors are painting the side of the ship and end up 'overboard', the far shot shows them - as has the entire scene - on the port side of the ship, however the closeup alone shows them on the starboard side (the water changes direction in each shot).
The United States entry into World War One is portrayed as coming as a complete surprise to Ginger Rogers and her male friends. In fact, a declaration of war had been pending before Congress for days before the House and Senate voted resolutions. President Wilson signed the Declaration of War on April 6, 1917.
When the crews goes top-side on the submarines, nothing is wet though they just surfaced.
The film begins before the U.S. entry into World War I, but during the bus tour at the beginning, a large sign for the 1931 film An American Tragedy (1931) is seen.