Open 5.70 Information, Review, Specs

The boat’s lineage includes several siblings within the Finot "Open" family. The smaller Open 5.00 offers a more dinghy-like experience for light-crewed teams, while the Open 6.50 (often referred to as the Open 6.5) provides a more robust offshore-capable platform that served as a precursor to the Mini 6.50 movement. The 5.70, however, hit the "sweet spot" for one-design racing, earning it the title of "One-Design of the Year" from Sailing World in 2007. This recognition helped solidify the class in the United States, particularly in Southern California and the Pacific Northwest, where its ease of rigging and spirited performance aligned with the needs of modern sportboat enthusiasts.

Sailing Performance & Handling

The Open 5.70 is engineered for speed, specifically designed to achieve double-digit knots on a reach with minimal effort. Its performance is driven by a high sail-area-to-displacement ratio, featuring a 188-square-foot mainsail and a massive 377-square-foot asymmetric spinnaker flown from a retractable carbon bowsprit. According to technical evaluations by Sail Magazine, the boat is remarkably stable for its weight class due to its 1.75-meter (5.74 ft) draft when the bulb keel is fully deployed. The lifting keel mechanism allows the boat to be launched from a ramp, yet provides the necessary righting moment to carry its generous sail plan in heavy air.

Handling is sharp and responsive, aided significantly by a twin-rudder system. These dual blades ensure that even when the boat is heeled significantly or powering downwind under the kite, the leeward rudder remains vertical and fully immersed, preventing the "spin-outs" common in single-rudder sportboats. Tracking is described as "dinghy-like" in its sensitivity to helm input, requiring an active touch and constant trimming. Because the boat is so light (roughly 1,100 lbs), crew weight placement is critical; moving the weight aft in a breeze is essential to keeping the bow out of the waves and initiating a plane.

Popular Mentions & Media

The Open 5.70 enjoyed a high-profile introduction to the American sailing scene, largely thanks to its selection as the platform for various match racing and youth development programs. Its most significant cultural milestone was winning the Sailing World Boat of the Year honors shortly after its U.S. debut, which praised the design for making high-performance sailing accessible to sailors who were transitioning out of 420s or Lasers but weren't ready for the complexity of a Melges 24. It has also been featured in numerous technical sailing videos and regional regatta broadcasts, often showcased as the "thrill-ride" boat for weekend warriors.

Known Issues & Buyer’s Checklist

When inspecting a used Open 5.70, buyers should focus on the specific mechanical stresses inherent to a high-load sportboat. While the hull is generally robust, the following areas require scrutiny:

• Keel Lift Mechanism: The retractable bulb keel relies on a winch and cable system. Inspect the cable for fraying and the winch for corrosion. More importantly, check the keel trunk for wear or "slop," which can occur if the boat has been sailed extensively in gusty conditions without proper shim maintenance.
• Mast Step & Compression: Given the high tension required for the rig to support the square-top main and spinnaker, the area around the mast step should be checked for spider-cracking or compression in the deck core.
• Rudder Gudgeons: The twin rudders put significant stress on the transom mounts. Ensure the gudgeons are tight and that there is no delamination around the mounting bolts.
• Carbon Component Fatigue: The bowsprit and, in some versions, the mast are carbon fiber. Check for UV damage (yellowing or peeling clear coat) and any impact fractures along the length of the sprit.
• Phileas vs. Hobie Construction: Earlier models built by Phileas in France are sometimes noted in owner circles for having slightly different finish qualities than the later Hobie-built versions. Buyers should verify the builder to understand the specific parts-support availability.

Community & Resources

The Open 5.70 benefits from an organized class structure, particularly through the USA Open 5.70 Class Association. This body manages the one-design rules that keep the racing competitive and fair. Technical support is frequently sought through the designer’s own archives at Groupe Finot, which maintains historical records of the boat’s specifications. In the United States, Open Sailing Inc. remains the primary historical touchpoint for class growth and distribution information.

The Verdict

The Open 5.70 is an uncompromising sportboat that prioritizes the visceral thrill of speed over creature comforts. It is an ideal choice for the sailor who wants to move fast, trailer easily, and race in a competitive one-design fleet without the overhead of a larger yacht.

Pros

• Exceptional Speed: Easily reaches planing speeds in moderate breeze.
• High Stability: The deep bulb keel and twin rudders offer security in heavy air.
• Ease of Transport: The lifting keel and light weight make it one of the most trailerable boats in its class.
• Modern Rig: The square-top main and asymmetric kite provide a contemporary racing experience.

Cons

• Extremely Wet: The low freeboard and high speeds mean the crew will likely be soaked in anything over 12 knots.
• Zero Amenities: The "cabin" is strictly for sail and gear storage; it is not suitable for overnighting.
• Crew Sensitivity: Small changes in weight distribution have a massive impact on hull speed and balance.