Routing
Master the art of route planning with FairWinds' advanced routing engine.
Overview
Routing is the process of calculating the optimal path from start to finish, considering:
- Wind forecasts
- Ocean currents
- Boat performance (polars)
- Course waypoints
- Weather systems
Routing Methods
Manual Routing
Place waypoints manually on the map:
- Click to add waypoints
- Drag to adjust positions
- View estimated times for each leg
- Refine based on weather
Best for:
- Short races
- Simple courses
- Learning weather patterns
Automatic Routing
Let the routing engine calculate the optimal path:
- Click Auto Route
- Engine analyzes weather forecasts
- Calculates fastest path
- Displays recommended route
Best for:
- Long ocean passages
- Complex weather patterns
- Competitive racing
Routing Algorithm
The FairWinds routing engine uses an isochrone-based algorithm:
How It Works
- Start Position: Begin at the race start
- Time Steps: Calculate all reachable positions at fixed time intervals
- Expansion: For each position, calculate where the boat can reach in the next time step
- Optimization: Choose paths that minimize total time to finish
- Waypoint Constraints: Ensure route passes required marks
Factors Considered
- Wind Speed & Direction: From weather forecasts
- Current Speed & Direction: Ocean current data
- Boat Speed: Based on polar performance
- VMG: Velocity Made Good toward the next mark
- Tacking/Jibing: Optimal angles for upwind/downwind sailing
Route Optimization
Wind Angles
Understanding optimal sailing angles:
| Point of Sail | Angle to Wind | Strategy |
|---|---|---|
| Close-hauled | 40-50° | Upwind, tacking required |
| Close reach | 60-80° | Fast and efficient |
| Beam reach | 90° | Maximum speed |
| Broad reach | 120-150° | Fast downwind |
| Running | 170-180° | Directly downwind |
Great Circle Routes
For long distances:
- Shortest path on a sphere
- May not be fastest due to weather
- Routing engine balances distance vs. conditions
Weather Routing
Strategic considerations:
- Pressure Systems: Route around lows and highs
- Wind Shifts: Anticipate changes in wind direction
- Current Boundaries: Cross at optimal angles
- Doldrums: Avoid or minimize time in light wind zones
Route Analysis
Estimated Time of Arrival (ETA)
The routing engine provides:
- ETA for each waypoint
- Total race duration
- Comparison with other routes
Route Comparison
Compare multiple routing strategies:
- Conservative vs. aggressive
- Northern vs. southern routes
- Different waypoint sequences
Real-time Adjustments
During the Race
Weather forecasts update during the race:
- New forecast data arrives every 6 hours
- Routing engine can recalculate optimal path
- Adjust waypoints to adapt to changing conditions
Manual Overrides
You can always override the routing engine:
- Add or remove waypoints
- Force specific routing choices
- Implement your own strategy
Advanced Techniques
Isochrone Analysis
View the routing engine's calculations:
- See all reachable positions at each time step
- Understand why certain routes are optimal
- Identify alternative strategies
Weather Window Planning
For long races:
- Identify favorable weather windows
- Time your passage through challenging areas
- Avoid predicted storm systems
Current Exploitation
Maximize benefit from ocean currents:
- Route through favorable current
- Minimize time in adverse current
- Use current boundaries strategically
Next Steps
- Understand boat performance and polars
- Learn about weather data
- Explore race formats