🔍 Key Concepts

• Meaning of turning for 9 mph in terms of speed through the water versus speed over the ground • How current (4.5 mph) at Knox Landing will affect your speed over the ground if it is with you or against you • Basic local navigation regulations on the Mississippi River (e.g., which bank to favor and restrictions near Old River Control)

💭 Think About

• If your engines are turning for 9 mph in still water and the current is 4.5 mph in the same direction as you, what would your speed over the ground be? What if it were against you? • Think about standard rules for tows on the Mississippi River: are they generally required to run close to the left descending bank, right descending bank, or mid‑river when safe? • Would every vessel be allowed to use an inflow channel near a control structure freely, or are there usually restrictions and special controls in such areas?

✅ Before You Answer

• Confirm the difference between speed through the water and speed over the ground and how they add or subtract with current. • Verify from 33 CFR 162.75 (Mississippi River regulations) which bank tows are directed to favor when safe. • Check on your chart and notes whether the Old River Control Structure area and related channels are open to all vessels and whether its lights are charted as an official range.