Propeller Slip Calculator
Calculate prop slip percentage and analyze propeller efficiency
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Common ratios: Outboard 1.75-2.3, Sterndrive 1.5-2.0, Inboard 2.0-3.0
Propeller Analysis
Propeller Slip
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Theoretical Speed
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Actual Speed
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Speed Lost to Slip
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Prop RPM
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Distance per Revolution
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Typical Slip Ranges
| Application | Typical Slip | Status |
|---|---|---|
| High Performance | 5-10% | Excellent |
| Planing Boats | 10-15% | Good |
| Semi-Displacement | 15-20% | Normal |
| Heavy Displacement | 20-30% | Acceptable |
| Overloaded/Wrong Prop | 30%+ | Poor |
Understanding Propeller Slip
What is Slip?
Slip is the difference between theoretical prop advancement and actual boat speed.
Formula: Slip % = (Theoretical - Actual) / Theoretical x 100
Some slip is necessary - zero slip means no thrust!
Optimizing Slip
Too much slip = wrong pitch or overloaded boat
Increase pitch to reduce slip (if RPM allows)
Consider 4-blade props for better grip in high-slip situations