You are turning 100 RPM, with a propeller...

Question 1 of 2707066636eea28f7522a1c51b6ee

You are turning 100 RPM, with a propeller pitch of 25 feet, and an estimated slip of -5%. What is the speed of advance?

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Question 1 of 27070

Q

You are turning 100 RPM, with a propeller pitch of 25 feet, and an estimated slip of -5%. What is the speed of advance?

🔍 Key Concepts

• Pitch speed (theoretical speed) from propeller: pitch × RPM • Effect of negative slip on speed of advance (does it make you go faster or slower than pitch speed?) • Conversion from feet per minute to knots (nautical miles per hour)

💭 Think About

• First, ignore slip and compute the theoretical speed based only on 25 ft pitch and 100 RPM. What distance in feet do you advance in one minute? • Next, apply a -5% slip factor. Should you increase or decrease the theoretical speed for negative slip? By what percentage? • Finally, convert your final feet-per-minute value to knots. Remember that 1 nautical mile = 6076 feet and 1 hour = 60 minutes.

✅ Before You Answer

• Make sure you correctly interpret -5% slip (is the actual distance traveled more or less than the theoretical pitch distance?) • Check that you convert minutes to hours correctly when going from ft/min to nautical miles per hour (knots). • After calculating speed in knots, compare your result to the choices and select the one closest to your computed value.