Combining design and styling by Humphreys Yacht Design with composite engineering by High Modulus, this was certainly a technically challenging project, adding to an already accomplished resume of high tech, high performance custom projects by McMullen & Wing.
Even with three MTU16V 4000 M90 series engines, each rated at 2,720 kW, and KaMeWa jet units, weight saving remained a critical requirement to achieve the high speed performance. The M&W design team embarked upon a program to critically analyze every component of the vessel to save weight; the vacuum infusion process of Carbon-fiber / Kevlar / Foam composite was utilized in the building of hull and superstructure, Titanium where possible for deck fittings and hand rails, and light weight veneered foam panels for interior joinery, all to Germanischer Lloyds Class and MCA.
Fitted with a generous array of navigation and communications systems, ERMIS2 is a state of the art vessel, complimented with an interior that is streamlined and light. Paint-treated ash and clear varnish maple combine with contemporary furnishings to create a modern nautical language.
The vessel has a relatively narrow 21’ beam and walk-around decks, thus she looks fairly small in comparison with large-volume around-the-world super yachts, but one only has to step into the bridge control room to realize what Ermis2 is all about. Here seven naval-style Stidd chairs are set up for heavy weather passage making. Surrounded by deep blue ultra-leather, they face an instrument panel that features mostly tried-and-tested Furuno gear augmented by C-Plath autopilot, gyrocompass and speed log, Sestrel compass, Echo Pilot sonar and Brookes & Gatehouse wind instruments.
Above on the flybridge, a troika of more relaxed-looking Stidds is doubtless meant for driving in less stringent conditions. Behind this is fore-and-aft seating for guests, a U-shaped lounge and table for al fresco dining, a sunpad and space for the rescue tender. Four prominent domes for the communications gear are also clustered aft. Deck fittings are partly M&W custom-made in titanium, again to reduce weight, and where stainless steel has been used, it is brushed to match. The forward windlass is from New Zealand-based Maxwell Winches, which supplies many superyacht yards worldwide, and a 3,306-pound C-Quip davit astern, by the swim platform, handles an Aquatx Delta RIB.
The principal lounge, dining area and galley are gathered in a conventional no-nonsense layout, and light, paint-washed ash veneer bordered by clear-finished maple is used throughout. Colonial-style overhead fans in the lounge and master suite, one beneath a skylight, are used to good effect, while the galley mixes Miele with equipment from New Zealand specialist Fisher and Paykel.
Below are two twin and two double staterooms, including the master, which is preceded by a common use lounge and study. Copious storage has been provided behind the paneling, and the same paint-washed theme runs through the lower deck to form a light and airy backdrop for the soft furnishings, with mirrors port and starboard in the owner’s stateroom furthering the sense of space.
The overriding theme is comfortable and minimalist, to comply with all-important weight considerations.
ERMIS2 is a very advanced large motor yacht. She is a highly engineered vessel, extremely light weighted and designed to take large loads. The hull bottom has been engineered to take vertical accelerations at the LCG in the following three load cases:
- • Long Range: 2.20g (Additional to gravity)
- • High Speed: 2.83g (Additional to gravity)
- • Light Ship: 2.95g (Additional to gravity)
All composite engineering design was carried out by High Modulus (NZ) Limited to fully comply with Germanisher Lloyds Rules for Special Craft (Yachts ≥ 24m (High Speed Craft) 2003).
The composite structure is certified to full Germanischer Lloyds class Notation 100 A 5 Motor Yacht (Unrestricted Range of Service). All composite construction was carried out in female moulds comprising of some hand laid and infused materials. ADR 246TG and ADH28 Toughened Epoxy System from Adhesive Technologies Limited NZ was used throughout the construction. All structures were post cured at 60 degrees Celsius for 48 hours.
Although all materials used in the construction were class type approved, additional material testing was performed by High Modulus for the purpose of structural certification by Germanisher Lloyds and to gain acceptance of the bond at the skin to core interface under high strain conditions.
Finite element analysis as defined by the Germanisher Lloyd rule was carried out on bulkheads E, F and H on a global model developed of ERMIS2.
Global finite element analysis was carried out to check the behavior of the vessels structure in an overall global loading condition. This model was subjected to two load cases. Firstly to represent high speed forward slamming (head seas) and secondly to represent high speed global torsion (diagonal seas). In each case the load was generated by a combination of hydrostatic and dynamic pressure, based on requirements set out by Germanisher Lloyd High Speed Craft.