Most assume that because of the modern electronics, the experience of the captain, pilot and crew and the power of the vessel that the 800 footer can, and will, just turn to avoid a recreational boater who inadvertently zips into its path unaware of its presence. The fact is, even at a slow speed of say four knots, a loaded 800 foot tanker can take a quarter mile and seven minutes to stop. Worse yet, when the engines are put in reverse, the large tanker looses all steerageway. In addition to the problem of stopping or maneuvering out of the way, the tanker has a blind zone which precludes them from seeing directly in front for up to 600 feet. Many recreational boaters assume that because large commercial vessels have radar that the commercial vessels will pick them up.
Problem is, the signal has to come back to the ship's radar in order for it to be seen.
Even with a radar reflector most small boats don't show up beyond a mile or two. Without a radar reflector one would be lucky to be seen beyond a quarter of a mile. Most boaters today have VHF radios and they are not bashful at using them to find where the fish are biting or to carry on conversations about where they are going to have dinner. All large vessels are required by regulation to listen to VHF channels 13 and 16. The safest and most efficient way of communicating with a large vessel to confirm what they are doing, or to tell them what you are doing, is by radio.