Answer: embarking

AnswerCrossword Clue
EMBARKINGWhat Columbus was doing on Aug. 3, 1492.
EMBARKINGSetting out.
EMBARKINGBoarding, as a ship
embarkingBegin (a course of action, esp. one that is important or demanding)
embarkingPut or take on board a ship or aircraft
embarkingEMBARK, to go on board ship, also IMBARK
embarkingGo on board a ship, aircraft, or other vehicle