MAT 1245 Sail Configuration Guide

Overview

The MAT 1245 is a high-performance cruiser-racer designed by Mark Mills, engineered for competitive IRC/ORC racing and fast coastal transit. Its design philosophy emphasizes a powerful power-to-weight ratio and versatile handling across a wide range of sea states.

Rig Specifications & Performance Analysis

Analysis of the P/E/I/J dimensions reveals a sophisticated racing platform:

• Mainsail Configuration: A P/E ratio of 2.88 indicates a high-aspect ratio rig, optimized for aerodynamic efficiency and superior upwind lift.
• Foretriangle Design: The I/J ratio of 3.50 is perfectly suited for high-performance, non-overlapping working jibs and specialized reaching sails.
• Sail Area: 88m² of total upwind sail area provides significant drive for the 12.45m hull.
• Performance: The rig is decidedly racing-oriented, prioritizing trim sensitivity and pointing ability.

Popular Sail Configurations

Due to the limited fleet size of two boats, configurations are highly customized:

• Mainsail: Typically high-modulus builds with optimized roach profiles to take advantage of the 16.58m luff.
• Headsail: Configurations generally focus on a versatile J1-J3 jib inventory to cover the full wind spectrum.

Key Characteristics

• High-aspect mainsail (P/E 2.88) ensures exceptional efficiency in light to moderate air.
• Balanced foretriangle (I/J 3.50) allows for high-tension forestay setups and precise jib shape.
• Deep 2.58m draft combined with a 3.78m beam provides the stiffness required to carry 88m² of canvas.
• Modern Mark Mills hull geometry delivers weatherly performance and reduced drag.

Sailing Considerations

• The high-aspect rig requires active backstay and car adjustments to depower the 48m² mainsail effectively.
• Optimal performance typically requires a coordinated racing crew of 8 to 10 for weight distribution and sail handling.
• The boat is exceptionally close-winded, rewarding precise helming and trim coordination.

Sailmaking Recommendations

For the MAT 1245, 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. For cruising or offshore delivery, add a taffeta protective layer on both sides to enhance UV resistance and abrasion protection. Based on the 2.88 P/E ratio, a tri-radial load-path layout works best to manage the high vertical loads of the tall mainsail. A typical inventory includes a high-aspect main, a light/medium jib, and a heavy-weather jib. With 88m² of sail area, plan to reef around 18-20 knots depending on the sea state.

Conclusion

The MAT 1245 is a refined racing machine that rewards high-quality, stable sail shapes and technical trimming. Explore sail options for MAT 1245 to unlock its full podium potential.