Navatech Ltd

Transportable 7-Meter Liveaboard Sailboat

rgubry — 2025-02-27T18:02:00Z

I just rediscovered a school project, transportable 7-meter liveaboard sailboat, that I created 20 years ago. Though I never got to build it, I've decided to give it a second life online - far better than letting it gather dust on a tiny USB key! This project holds so many memories, taking me back to my youthful sailing days…

Here is the English translation of the design pitch. 🙂

This sailboat is a 7-meter transportable liveaboard, designed for coastal cruising for a couple and a child on relatively short trips. It was intended to be built in small quantities by amateurs or small boatyards. The chosen construction method is sandwich composite over a male mould.

The design prioritizes stability, both in form and weight. Its 400 kg bulb lifting keel provides excellent stability while maintaining a shallow draft, allowing access to well-protected anchorages.

The cockpit is spacious, designed to maximize outdoor living. It can accommodate six adults around a removable table, which also serves as the interior saloon table and stows neatly under the cockpit, behind the stairs. The cockpit has been intentionally designed as a closed space for added safety, particularly for children.

Inside, the layout is optimized for functionality, compensating for the central daggerboard trunk. The saloon can comfortably seat four adults, and the twin balanced rudders ensure excellent control, even when heeling. Additionally, they can be individually lifted to reduce drag when the boat is properly trimmed.

Shell Penguin (Sept 2024)

Navatech_admin — 2024-10-25T05:48:06Z

Navatech Ltd was contracted by Boskalis Subsea Services to perform the seafastening of the MDL gen 2 Mobile Reel Drive system (MRDS) onboard the Boka Nortern Ocean as part of the Shell Penguin project. The MRDS assembly includes two towers of 60Te each, six lengths of 12m skidding track which are bolted to the Boskalis grillage to distribute the loading onto the deck. Additional steel has been added underdeck to strengthen two bulkheads.

The MRDS has installed new flexible from five reels over two trips.
First trip:

Fwd reel: 267.9Te
Middle reel: 235.6Te
Aft reel: 243.2Te

Second trip:

Fwd reel: 159.2Te
Middle reel: N/A
Aft reel: 149.4Te

(Photos courtesy Boskalis subsea Services)

Winch and Fairlead Grillage Design - Ithaca Captain Thruster Changeout (Aug 2024)

Navatech_admin — 2024-09-13T17:42:06Z

Navatech Ltd has been engaged by Boskalis Subsea Services to execute the seafastening and design of a fabricated lifting system, which includes a 25Te SWL ACE winch derated to 16Te SWL, a spooling gear, an 80Te fairlead, and a custom grillage to support the entire assembly. This lifting system will be secured aboard the Atlantis and utilized for the cross-haul of a subsea thruster for recovery and installation purposes.

(Photos courtesy Boskalis subsea Services)

WROV - Northern Ocean (Mars 2024)

Navatech_admin — 2024-09-13T16:18:27Z

Navatech Ltd has been engaged by Boskalis Subsea Services to execute the seafastening of a ROVOP work class ROV (WROP HD51, SWL=9.7Te) aboard the BOKA Northern Ocean. This WROP is set to replace the current WROV on the starboard side of the ROV deck. To facilitate this upgrade, the existing platform deck has been modified to accommodate the larger WROV.

(Photos courtesy Boskalis subsea Services)

10Te ACE Winch Seafastening Design - HARBOUR DECOM (Sept 2023)

Navatech_admin — 2023-09-13T18:06:00Z

Navatech Ltd was contracted by Boskalis Subsea Services to perform the seafastening of a 18Te WLL ACE winch derated to 10Te WLL. The winch was used in connection with a sheave post (20Te SWL sheave) to re-route a "tag line" wire and was fastened on board the Southern Ocean vessel .

The "tag line" was used to facilitate the recovery of the Victor JM structure, weighing 117Te.

FS2000 model of the winch grillage:

FS2000 models of the Tag line grillage :
Beam Model:
The beam model of the Tag Line Grillage includes a simplified representation of the structural framework, focusing on the primary load-bearing beams. This model is used to analyze the overall structural integrity and load distribution of the grillage.

Detail Shell Model:
The detail shell model provides a more granular analysis of the Tag Line Grillage and its connection to the tubular, capturing the intricate details and stress distribution.

Total Tyra project (2023 - 2024)

Navatech_admin — 2023-05-13T20:18:00Z

Navatech Ltd was contracted by Boskalis Subsea Services to support the Total Tyra project. This involved sea fastening various items such as chutes, winches, a Reel Drive System (RDS), and designing a lifting beam for recovering a 1Te caisson from a platform.

– The MDL Reel Drive System (RDS) Generation 1 was mobilized on the Boka Ocean as part of the Total campaign. The RDS tower assembly comprised two towers (each 30Te) and two lengths of 12m skidding track, which were bolted to the RDS grillage to distribute the load onto the deck. The reel was a 9.2m JDR reel loaded with product, with a combined reel and product weight of 240.8Te.

(Photos courtesy Boskalis subsea Services)

– 1Te Caisson lift check:

– Chute grillage sea fastening:

SSIV Installation - Total Valdemar (Fev 23)

Navatech_admin — 2023-02-16T21:33:00Z

Navatech Ltd was contracted by Boskalis Subsea Services to provide engineering services for the Svend and Valdemar Project.

The Valdemar A Valve Station structure (SSIV) was sea fastened onboard the Boka Southern Ocean. The structure weighs approximately 66Te and measures around 7.2m by 12.2m, with a height of 3.5m

(Photos courtesy of Boskalis Subsea Services)

Riser Lifting - Total Ikike (April 22)

Navatech_admin — 2022-04-13T21:07:00Z

Navatech Ltd was contracted by Boskalis Subsea Services to provide engineering services for the Total Ikike project. One aspect of the project involved designing the rigging for a 12-inch riser (weighing 16Te and 44.7Te) and its riser guard. Another aspect included the sea fastening of various items, such as a tooling skid A-frame.

(Photos courtesy of Boskalis Subsea Services)

Riser guard:

Tooling skid:

AQAM Module - DPE (Jan 22)

Navatech_admin — 2022-02-01T09:52:00Z

Navatech Ltd has been engaged by Boskalis Subsea Services to execute the seafastening aboard the DSV Constructor of a 40Te module platform for the AQAM platform.

(Photos courtesy Boskalis subsea Services)

Light RDS Spread - Total Campaign 3 (12/2021)

Navatech_admin — 2021-12-25T14:07:00Z

Navatech Ltd was contracted by Boskalis Subsea Services to perform the seafastening of a light weight Reel Drive system (RDS) onboard the Boka Polaris for the 2021 Total Campaign.

The system was an Aquatic Reel Drive System (AQPR-06D-80) able to work with reel up to 80Te

The RDS tower assembly includes two towers of 6Te each and one 6m reel of 67Te complete with product.

Experience gained by mobilizing heavier system was used by designing a new grillage to minimize the vessel mobilization time:
– One lift for the grillage
– Four cleats for the RDS grillage
– Eight Lashing chains attached to two deck beams fastened by six cleats in total.

(Photos courtesy Boskalis Subsea Services)