14 September 2026 · Yotters, independent yacht media
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Fleet & Launches

Antonini Navi's first full-custom: 33.5m, 4,300nm, 39.2 dB at anchor

Antonini Navi has delivered Matilde 7, the 33.5-metre steel yacht that opens its Seamore 34 line and marks the yard's move into full-custom building. The La Spezia yard did something unusual at the handover: it published the sea trial acoustics, including 39.2 dB(A) in the owner's suite at anchor with every system running. For a buyer weighing a one-off at this size, that is a figure to hold every other yard to.
31 July 20264 min readYotters DeskEdited by Leon Soliman

A first full-custom out of La Spezia

The delivery, announced on 30 July, is the first full-custom superyacht Antonini Navi has completed, and the first yacht built at its La Spezia facility. She launched in March, two years after construction began, at a private ceremony attended by her owner, an experienced Italian sailor who had chartered before he built. Hydro Tec drew the exterior and carried the naval architecture; Hot Lab took the interior. The steel and aluminium platform beneath her was developed in house, and it is what the yard intends to sell again.

Antonini Navi is known for commercial and refit work rather than private yachts, and Matilde 7 is the argument that it can do both. Aldo Manna, co-founder and sales manager, framed the project as evidence the yard can interpret and build a one-off at this level. Simone Antonini, founder and chief executive, called it the completion of a journey. Underneath the sentiment sits the commercial point: a yard that has delivered one full-custom can be shortlisted for the next, and until this month it could not.

The numbers most yards keep to themselves

Pre-delivery trials recorded 39.2 dB(A) in the owner's suite with the yacht at anchor and all systems running. Vibration in the main salon, the compartment sitting next to the engine room, measured 0.32 mm/s. Both are the kind of measurement that normally stays inside a build contract and never reaches a press release. Publishing them invites comparison, which is what a yard with one full-custom delivery behind it should want.

Comfort at anchor is where most owners spend their hours, and it is the hardest quality to judge from a drawing. A buyer holding these figures can put the same question to every other yard on his shortlist and see which answers with a measurement instead of an adjective. It also shapes the contract conversation, because a published number is one the yard can be held to at delivery. On a first hull from a builder without a long private-yacht record, that does more for the order book than another render.

4,300 miles at ten knots

The same trials returned a range of more than 4,300 nautical miles at a 10-knot cruise, with a top speed of 14 knots. That is real ocean capability on a 33.5-metre displacement hull, enough to cross the Atlantic with margin. The steel structure buys the range, and the weight keeps the speeds modest. An owner who wants 25 knots is not the buyer for this boat, and the yard has not pretended otherwise.

The yard positions Matilde 7 as its entry into the custom sub-500GT steel segment, and that ceiling does real work for an owner. Below 500 gross tonnes the crewing and survey regime stays lighter for the life of the yacht, which is why so much design effort at this length goes into volume that does not count. Getting a boat that crosses oceans to sit inside that limit at 33.5 metres is a narrower engineering problem than the profile suggests.

150 square metres you can close

The main deck carries 150 square metres of open-air space, much of which shuts behind large sliding glass panels. The upper deck adds a further 160 square metres, with roughly 50 of it shaded by the hardtop. Exterior styling borrows openly from tugboats, fishing boats and military craft, and resolves into a vertical bow, reverse-raked bridge windows and bridge wings that project clear of the hull. The yard calls it a crossover, which here means explorer capability without explorer plainness.

The convertible deck is the part a charter-minded owner should read twice. Space that works in a Riviera August and again in a wet Adriatic October stretches the usable season at both ends, which is the difference between a boat used ten weeks a year and one used twenty. Inside, Hot Lab worked in ribbed textures, antiqued glass and panelling lacquered in pastel shades, with teak holding the scheme together.

What is behind her

Matilde 7 is not a solitary hull in the yard's plan. The 31.2-metre Hanaa, another Hydro Tec design with a Hot Lab interior, is close to launch at 300 gross tonnes, with ten guests and 4,000 nautical miles of range. The 44-metre SUY 135, drawn by Fulvio de Simoni with naval architecture by Arrabito Naval Architects, is in build at 462 gross tonnes for ten guests, with a split-level aft deck and twin Jacuzzis. It is asking EUR 25,000,000.

A 40-metre steel yacht has also entered construction on spec, for delivery in 2028, and that is the clearest signal in the announcement. A yard that commits its own capital to a hull before it has a buyer expects the segment to hold its value. For an owner choosing among a crowded field of 30 to 45-metre builders, the question is which will still be building in 2030. A speculative hull answers that more honestly than an order book does.

What owners and crew report

What is good, and what to watch

Strong points

  • It published numbers most yards keep private39.2 dB(A) at anchor and 0.32 mm/s of vibration are verifiable figures a buyer can hold every other yard to, not adjectives in a brochure.
  • Real ocean range on a boat this size4,300 nautical miles at a 10-knot cruise, confirmed consistently across multiple trade outlets, is genuine crossing capability on a 33.5-metre hull.
  • The yard is betting its own capital on the segmentA 40-metre steel hull is already under construction on spec for 2028 delivery, ahead of a confirmed buyer, which is a stronger signal of confidence than another order-book announcement.
  • Deck space designed to close, not just to look open150 sqm on the main deck and a further 160 sqm above, much of it behind sliding glass, extends the usable season into shoulder months a purely open aft deck cannot cover.

What to watch

  • No price at all, in either directionEven the industry's usual placeholder ranges are absent; a buyer comparing this against Cantiere delle Marche or Vripack at a similar size has nothing published to work from.
  • One full-custom delivery is not a track recordAntonini Navi's prior work was commercial and refit, not private new-builds. Matilde 7 is the yard's only full-custom private superyacht to date, so there is no second delivery yet to confirm this result repeats.
  • Modest top speed for the size14 knots flat out is well below the 16 to 18 knots more common on similarly sized crossover and explorer designs; the range and quiet come at a real cost in outright pace.
  • The trial figures are the yard's own39.2 dB(A) and 0.32 mm/s were measured on Antonini Navi's pre-delivery trials, not by an independent surveyor or class society; no outside verification of those specific numbers was found.

Practical detail

Antonini Navi's first full-custom: 33.5m, 4,300nm, 39.2 dB at anchor
PriceNot published; listed on application, consistent with the yard's other current models
Build timelineConstruction began March 2024, launched March 2026, delivered 30 July 2026, roughly two years keel to handover
Sea trial figures39.2 dB(A) in the owner's suite at anchor, all systems running; 0.32 mm/s vibration in the main salon; 4,300+ nm range at 10kn; 14kn top speed, per Antonini Navi's own pre-delivery trials
Class ceilingBuilt to stay under 500 gross tonnes, which keeps the crewing and survey regime lighter for the yacht's working life
Comparable current projects at the yardHanaa, a 31.2m Hydro Tec/Hot Lab sister nearing launch at 300 GT; the 44m SUY 135, in build and asking EUR 25,000,000; a further 40m steel hull under construction on spec for 2028 delivery
Yard's track record before this deliveryCommercial vessels and refit work; Matilde 7 is Antonini Navi's first full-custom private superyacht and its first build at the La Spezia facility
What is not publishedThe build price, and any independent (non-yard) verification of the trial acoustics and vibration figures

Questions this story answers

What happened?

Antonini Navi has delivered Matilde 7, the 33.5-metre steel yacht that opens its Seamore 34 line and marks the yard's move into full-custom building. The La Spezia yard did something unusual at the handover: it published the sea trial acoustics, including 39.2 dB(A) in the owner's suite at anchor with every system running. For a buyer weighing a one-off at this size, that is a figure to hold every other yard to.

What is good about it?

It published numbers most yards keep private. 39.2 dB(A) at anchor and 0.32 mm/s of vibration are verifiable figures a buyer can hold every other yard to, not adjectives in a brochure.

What should an owner or buyer watch?

No price at all, in either direction. Even the industry's usual placeholder ranges are absent; a buyer comparing this against Cantiere delle Marche or Vripack at a similar size has nothing published to work from.

What do owners and crew report?

Aldo Manna said an owner choosing a full-custom project entrusts the yard with far more than construction, and that with Seamore 34 the yard has demonstrated the professionalism, mindset and technical structure to interpret, develop and build a project at this level, adding that the sea trial results and the owner's satisfaction are the real confirmation of the work. (Aldo Manna, co-founder and sales manager, Antonini Navi, quoted by Marine Industry News and BOAT International)

Who reported this?

BOAT International, YachtBuyer, Antonini Navi, Marine Industry News, SuperYacht Times.

Reported from primary sources: BOAT International, YachtBuyer, Antonini Navi, Marine Industry News, SuperYacht Times.
Yotters DeskEditor-in-Chief: Leon SolimanEditorial standards

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