Re: Boating 101+6½ - ANSWER
ANSWER Scenario 1 <br /><br />
Vessels that are restricted in their ability to move due to underwater operations, including diving, are required to display the navigation lighting and day shapes as described in Rule 27d. (Basically, 3 vertical all-around mast lights in a red/white/red configuration and 3 vertical day shapes in a ball/diamond/ball configuration.) This vessel has stand-on priority. When the vessel size is small enough to make the display of lights and shapes impractical, an alpha flag must be displayed; Rule 27e. In other words, smaller recreational boats used as diving platforms typically fit the requirement of displaying the alpha flag.<br /><br />Ironically, both the International and Inland rules state that if the lights and shapes cannot be displayed, then the lights and an alpha flag must be displayed. The alpha flag is a substitute for the day shapes, but not the required 3 vertical all around lights.<br /><br />
<br /><br />The diver down flag, red with a single diagonal white strip, is NOT a substitute for the required lights, day shapes, or alpha flag. In the late-80s/early-90s the new proprietors of a small recreational dive shop on the east coast prevailed in a civil suit to establish trademark recognition of the diver down flag. As plaintiffs they were able to prove the little shop they bought was the originator of the diver down flag nearly 50-years prior and in purchasing the shop they also purchased the flag design as an asset. The court agreed. They dont stand a chance of ever enforcing trademark protection. I question the appropriateness of any local rules (Florida, Mississippi, parts of So. California, others) that require the diver down flag to be displayed during diving since it is trademarked protected.<br /><br />Any requirement for a skier down flag is a local rule and they vary from one locale to another. In some states its a red flag; in others its an orange flag; in some its either red or orange. There may be other colors required.<br /><br />
ANSWER Scenario 2 <br /><br />
A vessel engaged in a speed trial may display the alpha flag. This vessel does not have stand-on priority. As a courtesy, you may wish to pilot your vessel in such a manor to allow this vessel to proceed on a steady course and speed with priority.<br /><br />Diving is a fairly new technology when compared to seamanship. The international code flags existed and had meanings long before anyone when underwater. I have not yet be been able to locate the authority for this, but I suspect this other meaning of the alpha flag has its origin in a time long past and the contemporary meaning is probably the result of the adoption of the 72 COLREGS in 1972. References for the use of the alpha flag during vessel speed tests can be found in older publications about the international code flags. There are also web sites with details about the use of international code flags that also mention the use of an alpha flag in this way.