A sea trial is done to check the performance of the diesel inboard and other systems, like the inmast furling, should the boat be so equipped. A sea trial is essentially a test drive of a boat.The tradition is to decide you like the boat, make an offer that is accepted, and schedule the sea trial. A sea trial is the marine equivalent of a test drive, crucial for assessing a vessel's performance before it is fully commissioned or sold. A sea trial is totally out of the question. Is it OK to just get a marine survey done with the boat out of the water? A sea trial or trial trip is the testing phase of a watercraft (including boats, ships, and submarines). It is also referred to as a shakedown cruise. The purpose of this document is to define the overall commissioning process of a Caterpillar Marine Engine. Installation. Jo Malone London is the home of iconic perfume and home products.