You guys are missing the point with respect to the foreign income tax exclusion, but that's understandable as you haven't dealt with it first hand.

Point: It does not matter one bit how much time you spend in the US.

There are two ways to qualify for the foreign income tax exclusion. Way one, the physical presence test, which is the 335 days outside the US that a previous poster referred to.

Way two, the bona fide residence test. This you qualify for after you have spent 1 full year working outside the US, regardless of how many days you spent in/out of country.

For anyone coming from the states, PriceWaterHouse files an extension for you and does not file your income tax return until you meet the bona fide residence test.

Example:

Say you showed up as a HKG based pilot in September of 2009. Regardless of how many days you spend in the US from September 09 until September of 2010, you WILL qualify for the foreign income tax exclusion on September 30, 2010. PWC files your 2009 tax return in October of 2010, after you have qualified for the exclusion based on the bonafide residence test. So no matter what month you show up in HKG and where you spend your vacation and days off, one year later, you WILL qualify for the exclusion based on the bona fide residence test. Plenty of reading about it here:

Foreign Earned Income Exclusion - Bona Fide Residence Test

As another poster pointed out, it really doesn't matter one way or the other to the pilot, as FedEx has taken away your individual ability to financially benefit from the exclusion; they do.