🔍 Key Concepts

• U.S. Aids to Navigation System (USATONS) – lateral system colors and shapes for marks on the starboard vs. port side when returning from seaward or going upstream on a river • How chart symbols show lighted aids, including the color of the light and the shape/color of the dayboard (daymark) behind the light • The meaning of AHP (Above Head of Passes) on the Mississippi River and how that affects which side is considered the ‘returning’ or upstream side

💭 Think About

• First, decide whether a vessel at mile 528.6 AHP on the river is generally considered to be going upstream or downstream when ‘returning’ and which side (right or left bank) that puts the mark on • Recall the standard lateral rule: "Red, right, returning" – then connect that with what color light and what dayboard shape you expect on that side of the channel • Look at how charted lighted aids in this river section are labeled: does the chart show an R or G and any note like "TR" or "SQ" that hints at the dayboard shape?

✅ Before You Answer

• Verify from your chart or exam reference which side of the river Anconia Pt. Light is on at mile 528.6 AHP • Confirm the standard shapes used for red vs. green dayboards (triangular vs. square/rectangular) in the U.S. lateral system • Double‑check that you are matching light color (red/green) with the correct dayboard shape before choosing among the options