ANDREWS 30 MK1 Sail Configuration Guide

Overview

The Andrews 30 MK1 is a performance-oriented cruiser-racer designed by Alan Andrews and built by Dencho Marine. It features a high-aspect rig and a balanced hull form intended for competitive club racing and spirited weekend cruising.

Rig Specifications & Performance Analysis

Analysis of the Andrews 30 MK1 rig dimensions reveals a focus on aerodynamic efficiency:

• Mainsail Configuration: A P/E ratio of 3.01 indicates a high-aspect rig, favoring lift over raw drag and providing excellent upwind performance.
• Foretriangle Design: The I/J ratio of 3.50 suggests a tall, narrow foretriangle ideal for non-overlapping or high-aspect jibs that maintain efficiency at close-hauled angles.
• Sail Area: With 45m² of total upwind area on a 9.17m hull, the power-to-weight ratio is optimized for light to moderate air performance.
• Performance: This configuration suggests a weatherly boat that is particularly close-winded and responsive to trim adjustments.

Popular Sail Configurations

• Mainsail: Standard high-aspect designs with moderate roach to clear the backstay.
• Headsail: Typically equipped with a 100-105% jib for maximum versatility, though larger genoas may be used in light-air regions.

Key Characteristics

• High Aspect Efficiency: The 3.01 P/E ratio minimizes tip vortex drag for superior upwind pointing.
• Vertical Foretriangle: The 3.50 I/J ratio allows for powerful, easy-to-tack headsails.
• Deep Draft Stability: The 1.76m draft provides the necessary righting moment for the tall 11.40m P dimension.
• Nimble Handling: Compact dimensions and efficient sail area make it highly maneuverable in tight race courses.

Sailing Considerations

• The boat performs best when kept flat; early reefing is essential to maintain speed as the high-aspect rig generates significant heel.
• Small crew requirements make it an excellent choice for shorthanded racing or family day sailing.
• Performance expectations include rapid acceleration and high sensitivity to mainsail traveler and jib lead positioning.

Sailmaking Recommendations

For the ANDREWS 30 MK1, we recommend SurgeX membrane sails as the optimal choice for most sailors. SurgeX uses continuous fiber construction where fibers are laid along load paths and embedded in a thin membrane, providing superior shape retention compared to traditional Dacron while being more affordable than premium laminates. The continuous fiber structure means less stretch over time, maintaining the designed sail shape for years.

For racing applications, specify a lightweight SurgeX configuration with minimal base weight to maximize performance in light air. For cruising or coastal sailing, add a taffeta protective layer on both sides to enhance UV resistance and abrasion protection. Based on the 3.01 P/E ratio, a fiber layout mimicking tri-radial load paths works best within the membrane to handle the high vertical loads of the tall luff. A typical inventory includes a full-batten mainsail, a high-aspect J2 jib, and a versatile asymmetric spinnaker. With 45m² of sail area, plan to reef the mainsail around 16-18 knots to keep the boat on its lines.

Conclusion

The Andrews 30 MK1 is a sophisticated platform that rewards precise sail trim and high-quality materials. Explore sail options for the ANDREWS 30 MK1 to unlock its full racing potential.