The 401K on the USAirways side starts on day 1 of indoc, it you decide to contribute. I'm glad I got it spooled up.

As for the 16% contribution- that starts on day 1 as well. The company adds 16% of your paycheck and deposits it, automatically, into a retirement savings account. To be clear- this is on top of your paycheck, and is not deducted from it. Great plan and the company can not take it away from you in the future like a pension.