FIRST 34.7 Sail Configuration Guide

Overview

The FIRST 34.7, designed by Farr Yacht Design for Beneteau, is a dual-purpose performance cruiser-racer optimized for IRC and ORC handicap systems. It is engineered for competitive club racers and coastal cruisers who prioritize responsiveness and speed-to-length efficiency.

Rig Specifications & Performance Analysis

• Mainsail Configuration: A P/E ratio of 2.85 indicates a tall-aspect rig designed for aerodynamic efficiency and lift.
• Foretriangle Design: The I/J ratio of 3.57 is optimized for high-aspect, non-overlapping jibs that offer excellent pointing ability.
• Sail Area: 53m² total upwind area provides a high power-to-weight ratio for a 10-meter hull.
• Performance: The Farr-designed hull and high-aspect foils create a weatherly vessel that excels in light-to-medium air.

Popular Sail Configurations

• Mainsail: Performance-oriented mainsails with moderate roach are common to maximize the tall P dimension.
• Headsail: Most owners utilize high-aspect 100-105% jibs for ease of handling and tactical efficiency in upwind legs.

Key Characteristics

• High-aspect rig (P/E 2.85) provides superior lift and narrow wind angles.
• Optimized I/J ratio of 3.57 facilitates quick tacking and efficient headsail trimming.
• Wide 3.37m beam offers significant form stability for the 53m² upwind plan.
• Fast-displacement hull design ensures quick acceleration out of maneuvers.

Sailing Considerations

• The tall aspect ratio makes the rig sensitive to backstay tension and traveler position for depowering.
• Ideally suited for a racing crew of 5–7, though the non-overlapping jibs simplify short-handed cruising.
• Performance expectations are highest in flat water where the high-aspect foils maintain maximum attachment.

Sailmaking Recommendations

For the FIRST 34.7, 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 a Technora fiber blend and minimal base weight to maximize performance in light air. For cruising or bluewater sailing, add a micro-taffeta protective layer on both sides to enhance UV resistance and abrasion protection. Based on the 2.85 P/E ratio, a tri-radial load-path layout works best to manage the high vertical luff loads. A typical inventory includes a performance mainsail, a Code 2 all-purpose jib, and an asymmetric spinnaker. With 53m² of upwind sail area, plan to reef around 18 knots to keep the boat on its lines.

Conclusion

The FIRST 34.7 is a highly refined Farr design that rewards precise sail trim and modern membrane technology. Explore sail options for FIRST 34.7 to maximize your performance on the racecourse or during fast coastal passages.