You are going ahead on twin engines when you...

You are going ahead on twin engines when you...

Question 1 of 2707066636ee728f7522a1c517ca8

You are going ahead on twin engines when you want to make a quick turn to port. Which actions will turn your boat the fastest?

Question 1 of 27070

Q

You are going ahead on twin engines when you want to make a quick turn to port. Which actions will turn your boat the fastest?

🔍 Key Concepts

• Effect of ahead vs. astern thrust on each side of a twin-screw vessel • How a conventional right-hand propeller behaves in ahead vs. astern • Relationship between rudder effectiveness and propeller wash (propeller race)

💭 Think About

• First, picture which way the bow will swing if you put ONLY the port engine astern while the starboard stays ahead. Then picture the opposite. • Ask yourself: in a very tight, almost pivoting turn, is the rudder or the differential thrust from the propellers doing most of the work? • For each choice, imagine looking at the boat from above: which combination of ahead/astern and rudder angle creates the strongest turning moment to port?

✅ Before You Answer

• Assume conventional right-hand propellers unless the question states otherwise. • Check which engine (port or starboard) going astern will push the stern to starboard and bow to port when the other is ahead. • Verify whether putting the rudder over will meaningfully help if most flow from the propellers is canceling out, versus when one shaft is clearly driving water over the rudder.