Hello and thank you for using Just Answer,To claim the foreign income exclusion, a taxpayer must be in a foreign country (not just out of the US).
The term “foreign country” includes the country's airspace and territorial waters, but not international waters and the airspace above them. It also includes the seabed and subsoil of those submarine areas adjacent to the country's territorial waters over which it has exclusive rights under international law to explore and exploit the natural resources.
The term "foreign country" does not include ships and aircraft traveling in or above international waters. Nor does it include offshore installations which are located outside the territorial waters of any individual nation.You will need to count the dayes you are in territorial waters of another country or at port for the 330 days required to exclude your income. You will not be allowed to count the days you are in international waters because that is not meeting the test for "in a foreign country".You will most likely not appreciate this answer because it is normal practice for peopel to say "Out of the US" and everybody else says they exclude their income.If you are a US citizen or Green Card holder then you need to be in a foreign countyr for 330 days in a 12 month period to exclude your income.
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