Design Brief & Intent
The primary mission of the Andrews 70 was to claim line honors in offshore distance races, specifically targeting the Transpac, the Pacific Cup, and major Mexican events such as the Newport to Cabo and Newport to Ensenada races. Unlike earlier, narrower sleds that could feel unstable and skittish when sailing on a reach or in close-quarters buoy regattas, Alan Andrews gave this 70-footer a beam of 15 feet. This beamier hull form dramatically increased initial stability and provided a wider platform to support an enormous masthead sail plan.
This design philosophy extended below deck, where every ounce of weight was treated as the ultimate adversary to performance. There are no heavy teak-veneered bulkheads, private owner suites, or luxurious lounges on these boats. Instead, the interior of the Andrews 70 is a triumph of utilitarian function. Built using lightweight carbon fiber and S-glass sandwich panels, the open layout is optimized for an active racing crew of 10 to 15 members. Accommodations typically consist of an open forepeak—often carrying a single Pullman berth—and a series of adjustable, lightweight aluminum pipe berths lining the port and starboard quarters aft to allow the crew to sleep on the high side. A minimalist galley and nav station are centrally located. The entire interior is painted in clean, bright whites to maximize light and visibility, maintaining a sparse aesthetic that leaves no doubt about the yacht's singular, competitive focus.
Variations & Configurations
Because the Andrews 70 was built in small numbers on a semi-custom basis, no two hulls are identical, and several have undergone extensive modifications throughout their racing careers. Hull structures vary by builder. While Dencho Marine constructed several hulls utilizing advanced wet-preg carbon fiber and epoxy laminates, other custom builders—such as AKE Ltd. in Tallinn, Estonia—built hulls like Trader using unidirectional S-glass, PVC foam cores, and high-performance epoxy.
Rig and keel configurations have evolved continuously to match changing handicap rules. The boat was originally designed with a towering multi-spreader masthead rig, but many were optimized as "Turbo Sleds" featuring extended carbon fiber bowsprits and massive spinnaker poles to carry oversized downwind sails. Conversely, when owners sought to align their boats with the strict class parameters of the Santa Cruz 70 fleet under Offshore Racing Rule (ORR) rating systems, some hulls were "de-turboed". A prime example of this occurred when owner Philippe Kahn modified Pegasus, cutting 12 feet off the carbon mast, shortening the keel fin, adding lead ballast inside the bilge, and eliminating the bowsprit to create a simplified, easily managed sail plan that could be driven to its full potential by a short-handed crew. Draft options also varied, with some yachts utilizing a deep, 12-foot racing fin keel for maximum lift and stability during offshore passages, while others featured a slightly shallower, 9.5-foot keel to facilitate access to shallower harbors.
Sailing Performance & Handling
Evaluating the Andrews 70’s design parameters reveals a yacht built to fly. With a displacement of just 26,300 pounds against a waterline length of 60 feet, the yacht has an exceptionally low displacement-to-length ratio of 54.36. This extreme lightness allows the flat-bottomed hull to break free of its bow wave, rise onto a plane, and surf continuously on ocean swells, reaching speeds in excess of 20 knots downwind.
This high-speed potential is fueled by a monstrous sail area-to-displacement ratio of 31.53, indicating a power plant that can generate impressive boat speed even in a light breeze. To prevent the boat from simply laying over under this massive rig, the ballast-to-displacement ratio stands at a substantial 45.25 percent, concentrating 11,900 pounds of lead in a bulb at the tip of a deep fin keel.
At the helm, the Andrews 70 is extraordinarily responsive and acts like a oversized dinghy. Its capsize screening formula of 2.02 and a comfort ratio of 17.64 illustrate its lively, motion-intensive character. In a seaway, the ride is active, wet, and highly dynamic, requiring a skilled and attentive helmsman to anticipate waves. Downwind, the boat's flat-bottomed design is prone to dramatic surfs, but high-speed tracking requires constant coordination between the driver and the spinnaker trimmers. In heavy air, failure to steer precisely can result in a sudden round-down or broach, making the handling of this yacht an athletic, high-adrenaline endeavor.
Known Issues & Triage
Operating a 70-foot carbon fiber racing machine under high-load ocean conditions exposes specific structural and mechanical areas that require vigilant triage and maintenance.
- Rig and Chainplate Loading: The colossal loads generated by the towering rig put immense tension on the mast step, standing rod rigging, and chainplates. Sudden dismastings, though rare, have occurred under extreme racing conditions. Standard triage requires regular non-destructive testing (NDT), such as dye-penetrant or ultrasound inspections, of the carbon fiber mast tube, spreaders, and metal chainplate terminations to detect micro-fractures before they lead to structural failure.
- Core Integrity and Delamination: Because these hulls are sandwich constructions of carbon fiber or S-glass over foam or honeycomb cores, decades of hard driving into head seas can lead to localized delamination. Inspectors must systematically sound the hull with a tap hammer, paying special attention to the bow slam-zones, the area surrounding the mast step, and the structural grid around the keel trunk.
- Rudder Post and Bearings: Sleds use high-aspect spade rudders that experience severe bending moments and torque. Rudder post failures have led to catastrophic water ingress and vessel loss in the wider sled class during offshore races. Owners must regularly inspect the rudder post welds, replace worn rudder bearings, and service the shaft seals to ensure the steering assembly remains robust and watertight.
- Keel Grid Fractures: The deep fin keel acts as a massive lever against the bottom of the hull. The internal transverse floor grid and longitudinal stringers must be inspected for laminate cracking or separation from the hull skin, especially after any grounding or heavy offshore passage.
Modernization & Upgrades
As these vessels age, owners have kept them competitive and viable through targeted modernization programs. A key upgrade is replacing the original, aging Yanmar diesel engines with newer, more efficient turbocharged Yanmar marine units (such as the 4JH2-HTE series) coupled to modern sail drives to provide reliable propulsion and battery charging.
Electrical system modernizations are highly popular among contemporary teams. Upgrading the house battery bank to lightweight Lithium Iron Phosphate (LiFePO4) chemistry allows the yacht to run high-load systems—such as modern marine electronics, high-capacity watermakers, and active navigation computers—for days with minimal engine-run times. This conversion also saves significant weight compared to traditional lead-acid batteries, aligning with the boat's ultralight design brief.
Rig upgrades frequently include converting older, heavier aluminum spinnaker poles to high-modulus carbon fiber poles, updating hydraulic control blocks for the vang, backstay, and outhaul, and installing modern low-stretch Dyneema running rigging to handle the high static loads.
In some unique cases, owners have undertaken radical retrofits. The most famous is the full powerboat conversion of the hull Acharné. Her rig was completely removed, active fin stabilizers were fitted, the deep racing keel was shortened, and she was repowered with a heavy-duty Cummins turbo diesel. This turned her into an incredibly efficient, long-range power cruiser capable of easily cruising the Pacific while utilizing a fraction of the fuel required by a traditional displacement trawler.
Market Snapshot & Economics
On the brokerage market, the Andrews 70 represents a highly specialized, niche segment. Because of their pedigree and classic status, these yachts are scarce and trade at a relative value compared to modern, complex grand-prix racers. They offer an incredibly cost-effective route to securing line honors and competitive PHRF or ORR racing.
However, prospective buyers must look beyond the initial purchase price to the long-term economics of operating a 70-foot racing machine. The purchase price of an Andrews 70 is often dwarfed by its operational and refit costs. A single new carbon fiber mainsail or a high-performance downwind spinnaker can easily run into five figures, and maintaining a competitive inventory of sails requires a continuous, substantial budget. Furthermore, rig services, composite hull repairs, and the logistics of managing a large, professional-level crew mean that the Andrews 70 is best suited for dedicated racing programs or experienced owners with the resources to properly maintain a high-performance offshore thoroughbred.
The Verdict
The Andrews 70 remains an iconic monument to the golden age of the West Coast sleds. For the sailor who lives for the thrill of high-speed ocean surfing, sustained double-digit speeds, and the tactical challenge of grand-prix racing, few boats offer a more rewarding or raw experience. It is a purebred racing machine that demands a skilled crew and deep pockets to maintain, but in return, it delivers legendary performance and a permanent place in offshore sailing history.
Pros
- Exhilarating off-the-wind sailing performance with the ability to easily plane and surf in downwind conditions.
- High-quality, robust composite construction from premier yards like Dencho Marine.
- Cost-effective entry point to grand-prix offshore racing and line-honors capability compared to modern yachts.
- Highly responsive helm feel that behaves like an oversized racing dinghy.
- Strong class prestige with an active community in classic Pacific ocean races.
Cons
- Spartan, strictly functional interior with no comfortable cruising accommodations or luxury joinery.
- Exceptional operational and maintenance costs, where sail replacement and rig upkeep can quickly exceed the boat's market value.
- Demanding and athletic to sail, requiring a large, experienced crew to handle safely in heavy air.
- Deep draft limits cruising options, preventing access to many shallow harbors, anchorages, and standard marinas.
