reasonable, flying the burgee in the starboard rigging is such a widespread custom that to try to end it would be close to  impossible.  It is a small, custom-designed, and custom-made flag that carries symbols standing for the owner, so it can basically be  anything. The signal may be flown day or night, but is not displayed when another sailor is in command. (The rule is: the  private signal and burgee follow the sailor, not the boat.)  On a multi-masted boat, the private signal is flown at the head of the aftermost mast. On a sloop, the private signal may  be flown from the starboard rigging, either below the burgee or alone.  As a matter of courtesy, it is appropriate to fly the flag of a foreign nation on your boat when you enter and operate on its  waters. There are only a limited number of positions from which flags may be displayed. Therefore, when a flag of another  nation is flown, it usually must displace one of the flags displayed in home waters. However, it is hoisted only  after  the  appropriate authorities have granted clearance. Until clearance is obtained, a boat  must  fly the yellow  “ Q ” flag. All  charter boats should carry the national flags of neighboring islands as well as the yellow flag, in case charterers want to  visit those islands.  The courtesy flag is flown at the boat's starboard spreader, whether the United States ensign is at the stern staff, or flown  from the leech. If there is more than one mast, the courtesy flag is flown from the starboard spreader of the forward mast.  As a side note, some authorities are not amused at all if you fly their courtesy flag using an old, raggy flag. Some will even  fine you for disrespect! It happened to a friend of mine who was chartering in Turkey.  Lastly, it is also a common courtesy to fly the national flag(s) of your guest(s) on board, if they have a different nationality  than the ensign is showing.  Although flags come in standardized sizes, there are guidelines to help you selecting the proper size for your boat. The size of a nautical flag is determined by the size of the boat that flies it. Flags are more often too small than too large.  So in the rules below, round upward to the nearest larger standard size.  Fly the ensign from morning (8:00 a.m.) to evening (sunset) whether the boat is at rest, under sail, or under power. The  exception to this rule is: The ensign is not flown by a boat in a race, which signals to other boats that you are racing.  137 Raising and LoweringFlags Flags' Dimensions  Courtesy Flags  Private Signal  BrentPutnam’s PrivateSignal  Marshall22 –  Cranberry  The flag at the stern of your boat: U.S. ensign or national flag should be about one inch for each foot of overall length.  For example, on a 40ft. boat, the ensign should be 40 in. i.e. about 3.5ft.   Other flags, such as club burgees, private signals and courtesy flags for use on sailboats should be approximately 1/2  inch for each foot of the highest mast above the water. For example, on a 30ft. boat, with 50ft. between the masthead  and the water, the burgee should be about 25 in. i.e. about 2 ft. The shape and proportions of pennants and burgees  will be prescribed by the organization which they relate to.