Higher propeller slip generally leads to what outcome for a vessel's thrust and efficiency?

Higher propeller slip generally leads to what outcome for a vessel's thrust and efficiency?

• A. Increased thrust and efficiency.
• B. No change in thrust or efficiency.
• C. Reduced thrust and efficiency.
• D. Only affects speed, not thrust.

Answer: (C)

Higher propeller slip means the propeller is less effective at turning shaft power into forward push. As slip increases, more of the energy goes into swirling water and a larger wake rather than producing forward thrust, so the thrust the propeller can generate decreases for the same shaft power. Propulsive efficiency is the ratio of useful power (thrust times ship speed) to input shaft power, so when slip rises, that ratio falls because thrust drops while the power input stays the same. In short, greater slip wastes more energy in the wake and reduces both thrust and overall propulsion efficiency.

Higher propeller slip means the propeller is less effective at turning shaft power into forward push. As slip increases, more of the energy goes into swirling water and a larger wake rather than producing forward thrust, so the thrust the propeller can generate decreases for the same shaft power. Propulsive efficiency is the ratio of useful power (thrust times ship speed) to input shaft power, so when slip rises, that ratio falls because thrust drops while the power input stays the same. In short, greater slip wastes more energy in the wake and reduces both thrust and overall propulsion efficiency.