Of the following propulsion modes, which one...

Question 1 / 270705eccefa3bacbc34ba4d47ceb

Question 1 of 270705eccefa3bacbc34ba4d47ceb

Of the following propulsion modes, which one would operate with a geared-drive featuring a double reduction?

Question 1 of 27070

Of the following propulsion modes, which one would operate with a geared-drive featuring a double reduction?

🔍 Key Concepts

• Slow, medium, and high speed diesels are classified mainly by their RPM range • Why geared-drive and especially double-reduction gears are used between an engine and a propeller • Typical propulsion arrangements for large ocean-going ships vs. small high-speed craft

💭 Think About

• Think about which engines usually run at very high RPM compared to the propeller’s optimal RPM • Ask yourself: when the engine RPM is much higher than the propeller RPM, do you need more or less reduction in gearing? • Consider which of the listed prime movers most commonly drives a controllable-pitch or fixed-pitch propeller through reduction gearing rather than directly

✅ Before You Answer

• Know the approximate RPM range for slow, medium, and high speed diesels and gas turbines • Recall which engine type is often direct-coupled to the propeller shaft (no or minimal reduction gearing) • Identify which propulsion mode typically requires large reduction ratios and therefore may use double-reduction gearing

Question 1 of 27070

Of the following propulsion modes, which one would operate with a geared-drive featuring a double reduction?

Slow speed diesel

Medium speed diesel

High speed diesel

Gas turbine