Sea trial
![Nobiskrug new ship Sabine Howaldt on sea trials in the Kiel Fjord in May 1958](/Images/godic/202501/14/MS_Sabine_Howaldt_-_Kieler_Förde_-_im_Mai_1958_auf_Probefahrt_11141.jpg")
A sea trial is the testing phase of a watercraft (including boats, ships, and submarines). It is also referred to as a "shakedown cruise" by many naval personnel. It is usually the last phase of construction and takes place on open water, and it can last from a few hours to many days.