HH55 and HH66 Review: Morrelli & Melvin’s Carbon Cats for Buyers

Sailing catamaran heading into the sunset

This buyer’s review covers the HH55 and its big sister, the HH66: two all-carbon, daggerboard performance catamarans designed by Morrelli & Melvin and built in China. We pulled together builder data, magazine sea trials and current listings to answer what a buyer needs to know: what each boat is, how the magazines found them under sail, what to check, and who should pass on them.

Last checked: November 2026. This is a compiled review, not our own sea trial. Specifications come from the cited magazine reviews and the builder, and these semi-custom boats vary from hull to hull. Prices are asking prices or list prices at the time of publication, not sale prices.

Who builds them and where they came from

HH Catamarans is the semi-custom brand of Hudson Wang, whose company Hudson Yacht and Marine had a background in non-marine products before it went into boatbuilding. Wang teamed up with Kiwi boatbuilder Paul Hakes. Gino Morrelli and Pete Melvin drew the lines. Hakes had been involved with the original Gunboat brand, and Morrelli & Melvin had designed Gunboats before, including the Gunboat 90. Boats.com’s review described HH as an attempt to fill the gap at the top of the market that Gunboat’s departure had left.

Sources disagree on the exact yard location. SAIL’s spec boxes put the builder in Quanzhou; the builder’s own model pages say Xiamen. Ask the seller for the build documents of the specific hull.

The 66 came first. Hull #1, R-Six, was tested by SAIL on a 300-mile Mediterranean passage for its February 2017 issue, and Yachting World’s Rob Melotti raced aboard her at the St Maarten Heineken Regatta that March. According to boats.com, three 66s had already raced in the Caribbean and the Mediterranean when the first 55, Minnehaha, was reviewed sailing on the US East Coast.

One detail for anyone reading older brochures: the builder’s HH55 page still names Morrelli & Melvin, but its current HH66 page speaks of in-house design and engineering and does not credit them, while every magazine review of the early 66s does.

Versions, hull numbers and what has changed

Both models come in two cockpit layouts, which matters more than any spec-sheet number:

SC (aft helm): twin raised helms on the stern quarters, with a working cockpit forward of the saloon for halyards, reefing lines and sheets.
SCF (forward helm): a single steering station at the front of the saloon, with lines handled in the forward cockpit.

The builder’s model pages say five 66s have launched (the first R-Six, the latest Nemo) and five 55s (one forward-helm boat, four with aft helms). Those counts look out of date: a 2022 55 offered for sale in Spain this year is described by its broker as hull number 7. The builder states production of the 55 at one to two boats a year.

The engines have changed too. The boats tested in 2017 had Yanmar diesels on saildrives. HH’s model pages now list standalone diesels on shaft drives or a parallel diesel-electric hybrid it calls EcoDrive. The 55 has also been followed by an HH56, which a current new-boat listing describes as an evolution of the 55, with shaft drive and a three-cabin-plus-crew layout. If you are comparing a used boat with a new one, check which drive system each has.

Published specifications

	HH 55	HH 66
LOA / LWL	54ft 6in / 54ft 6in	66ft / 65ft
Beam	27ft	28ft 6in
Draft, boards up / down	4ft 11in / 10ft 11in	5ft / 13ft 2in
Light displacement	30,864 lb	37,479 lb
Sail area (main + jib)	1,789 sq ft	2,333 sq ft
Air draft	88ft 3in	90ft 10in
Fuel / water	185 / 127 US gal	200 / 160 US gal
Engines (test boats)	2 x 57 hp Yanmar, saildrives	2 x 80 hp Yanmar, saildrives
SA/D / D/L	30 / 85	31 / 65
Base price when reviewed	$2.4 million (2017)	$3.7 million ex factory (2017)

Source: SAIL boat reviews of both models, 2017. Other published weights differ. Katamarans.com lists the 55 at 14,200 kg light and 19,633 kg maximum. Sailing World said the 66 ends up at about 46,000 lb, and Yachting World quoted about 20 tonnes. Those look like loaded weights rather than light ship. Expect a cruising-ready boat to be well above the light-ship number.

Construction is the same idea on both: a carbon and foam-core sandwich, epoxy-infused in female moulds. For the 66, SAIL names Corecell foam and post-cured epoxy, says hulls and deck are laminated into one monocoque, and notes that the interior furniture and bulkheads are also carbon composite. The rigs are carbon (Southern Spars on the 66), the standing rigging is aramid, and the curved daggerboards and rudders are carbon. T-foils on the rudders and boards are optional on the 66.

How the magazines found them under sail

The 55

Chris Caswell tested hull #1 for SAIL in light air. Upwind, the boat made 8 to 9 knots in 8 to 9 knots of true wind. With the furling reacher set in about 11 knots, it made 10 to 11 knots. Gino Morrelli says the boat will point as high as 45 degrees, with 48 degrees as its sweet spot. Under power it made 12 knots on both engines and 6.5 on one. The curved C-boards are said to give the bow about 15 percent lift at 20 knots.

His reservations are useful for a buyer. He found the steering a bit stiff, and he doubted the forward cockpit would be pleasant in spray. The boards have to be raised and lowered on every tack. The plumb, slightly reversed bows give waterline length but a wetter ride. He also said the boat does not suit cruisers who want simple gear. Herb McCormick sailed the same model on Chesapeake Bay in about 11 knots for Cruising World’s Boat of the Year contest (review published in 2018). He gave no speed figures but wrote that only the bigger 66 sailed better. Judge Ed Sherman thought a couple could handle the 55 without outside help.

The 66

Peter Nielsen’s SAIL test on R-Six gives the most data. Upwind he saw nearly 15 knots of boat speed at 35 degrees apparent in 21 knots true. Off the wind he reported the boat sailing at close to true wind speed. Under power it made 13 knots. Seas were slight during his passage, so the test says little about motion in a big sea, and he noted that a single forward wheel would make shorthanded sailing easier than the twin aft helms he tested.

Cruising World’s judges watched the speedo pass 8.2, 10.4 and 12.5 knots on a tight reach in 12 to 14 knots on Chesapeake Bay. Judge Bill Bolin counted roughly 19 lines in the forward cockpit. Ed Sherman said he could not picture a middle-aged couple taking it round the world without extra crew. Sailing World named it Best Multihull in its 2018 Boat of the Year awards. Its judges praised the light helm and the build quality, and said the boat needs a full-time captain, plus a few paid hands and eight to ten experienced crew for racing. In Yachting World, Gino Morrelli said the 66 starts to fly a hull at about 25 knots of true wind. In the Heineken round-the-island race, R-Six flew a hull for a few minutes above 20 knots of boat speed.

Living aboard

Both boats are offered with three or four cabins. On the 55 tested by SAIL, the owner’s suite took the port hull, with a hidden washer-dryer. There were guest cabins forward and aft to starboard, and one forward head had been turned into a workshop. The galley is to starboard in the saloon. On the forward-helm version, the steering position sits inside the front of the saloon.

On the 66, the owner’s suite shares the port hull with a small crew cabin. The two starboard cabins on R-Six each had a queen berth and their own head. SAIL listed air conditioning, a washer-dryer, freezers, twin Fischer Panda generators and a 720 Ah lithium bank among the equipment. Cruising World notes that the heavy gear, including generator, hydraulics and batteries, lives in a forward locker. These are big-boat systems, and they need big-boat maintenance budgets.

HH55 or HH66: which one fits your crew

The reviews point one way. The 55 is the one a capable couple can run, and that is what HH designed it for: a more manageable version of the 66. The 66 is quicker and roomier, but every test crew assumed a professional or several skilled hands, especially for racing or long passages. If you will sail mostly as two, look for a 55, and give the forward-helm layout serious thought, because it keeps the person steering close to the lines. The 66 makes sense for an owner who already plans to pay a captain.

Beam is the other practical filter. At 27 to 28.5 feet wide, both boats will need end-ties or large-yacht berths in many Mediterranean and US marinas. Check availability and rates in your home port before you make an offer.

Weak points and what a survey should cover

Every hull is semi-custom, so no two boats have the same systems. Plan the survey around the boat in front of you. Our catamaran survey guide covers the general process. On these boats, add the following:

Carbon laminate: hire a surveyor with carbon and epoxy experience, ideally with thermal imaging or ultrasonic tools. Standard moisture meters can give misleading readings on carbon.
Daggerboards and wells: the curved boards run in wells with Vesconite bearings. Pull the boards if the yard allows, and look for grounding damage, bearing wear and cracks at the trunk.
Rudders and any T-foils: look for impact damage, bearing play and the condition of the foils.
Aramid standing rigging: fibre rigging has a service life set by its maker. Get the install date, and ask the rigger or Southern Spars what that particular rig needs.
Hydraulics and push-button controls: on the 66, sheets, traveller and daggerboards are worked by push buttons at the helm, and the mainsheet is trimmed by hydraulic rams. Ask for service records for the rams, pumps and seals.
Digital switching and lithium: the 55 Cruising World tested used CZone, and the 66 SAIL tested had a touchscreen distributed power system. Both, and big lithium banks, need documentation. Get the wiring diagrams and the battery management settings, and confirm the batteries’ age.
Engines and drives: saildrive boats need seal and diaphragm history. The 2022 55 currently for sale shows 1,733 and 1,977 hours on its two engines, a lot for a boat of that age, so ask how they were run up and get the service log.

Katamarans.com’s model page warns that maintenance on the 55 will be high. With a small fleet, many parts come from the builder or the original suppliers, so ask how quickly the current owner got spares.

New and used prices

When new, SAIL gave $2.4 million base for the 55 in 2017. Cruising World said over $2.5 million, and Katamarans.com quotes $2.8 to 3.0 million depending on options. For the 66, SAIL quoted $3.7 million ex factory. Cruising World put its test boat at more than $4 million, and Sailing World at about $4 million.

Very few come up for sale. In November 2026 we found a 2022 55 (hull 7) in Valencia listed on boats.com at US$2,490,000. A broker page for what appears to be the same boat showed $2,390,000 and said, in different places, that the boat was both withdrawn and still available. Confirm status and price directly. We found no 66 with a verified current asking price. Expect brokers to price them one at a time on their spec and history. The HH55 specs page on catamarket links to any listings we carry.

Who should look elsewhere

Pass on both boats if you want simple gear, a hand-steering position under cover on long passages, or low running costs. Look at these instead:

Outremer 55: a series-built French performance cruiser in the same size range. Compare build method, layout and after-sales support side by side.
Gunboat 62: from the brand Hakes and the designers worked with before. Any example is older and rare, so the survey matters even more.
Catana 53: also a daggerboard cat, built as a series-production cruiser rather than a semi-custom carbon boat.

If you own one of these cats and are thinking of selling, a listing on catamarket is free for private sellers. It includes up to 15 photos, stays online for 12 months and carries no commission. Buyers can browse the whole catamaran marketplace.

Related guides

Sources

Cover photo: Hugh Whyte on Unsplash.