Al Emirat was the first to begin what would be an incredibly dramatic conversion (look at this crazy pic of her in a half-built state here ). Designed by vaunted Pierrejean Design Studio, the project was dubbed Swift141—a name indicating she was to be fast and 141 meters long—during its development and reconstruction. The vessel that had worn two other names in its past would reemerge from Abu Dhabi's ADMShipyards after three years of work as Yaz—one of the world's largest, fastest, and certainly most unique superyachts. But it wouldn't be until 2015 that she would be fully outfitted and delivered in a fully operational state.

The second-hand frigates served with the UAE Navy as Al Emirat and Abu Dhabi for a decade, finally being decommissioned in 2008. But that was not the end of their story. The hulls were in good shape and their hardy qualities and efficient hull-forms made them attractive for repurposing. The fact that prominent UAE royal and politician Hamdan bin Zayed bin Sultan Al Nahyan was looking for a new pleasure boat and a project to help jumpstart a new shipyard group in Abu Dhabi also helped the prospects for such a project.

The Cold War era Dutch frigates were built tough as it would spend much of its life operating in the rough and unforgiving waters of the North Sea. The class was somewhat of an export success as well with Greece receiving two Kortenaer class ships right off the line. Once the Royal Netherlands Navy moved to retire the type in the late 1990s, they were snapped up by foreign Navies, namely Greece, which bought all but two of them, with the outstanding pair going to the United Arab Emirates.

The Netherlands also built two Jacob van Heemskerck class ships which were basically air defense versions of the Kortenaer class and Germany's Bremen class was based on the Kortenaer class design as well.

HNLMS Piet Hein was the fifth ship in her class and was launched in 1978. The ship displaced 3,900 tons and was equipped with a ' combined gas or gas propulsion ' system that allowed for highly efficient loitering and cruise operations by using small, lower powered turbines, while also having the ability to run at high speed with the help of larger gas turbines. This was a particularly relevant setup for submarine hunting operations, which was the Kortenaer class's primary role.

Of all the world's superyachts, Yaz stands out as one of the most exotic. The 463 foot long gleaming white and turquoise vessel is intended to resemble a dolphin. It's hard to argue that its designers didn't achieve that goal. But Yaz's slender, sculpted hull didn't emerge from the CAD software at a top naval architect's office, it came from the past—literally. Yaz is built on the hull of the Kortenaer class frigate HNLMS Piet Hein.

I wish I could post a large series of pictures or videos showing what is surely the incredible interior of this frigate turned superyacht, but there aren't any images available. This isn't really surprising when you consider who owns the vessel and that it is not available for charter. But we do have a couple renderings from Pierrejean Design Studio of what it is supposed to look like. Most notable is the master suite, which, judging by the rendering, sits just below the bridge as part of the glazed superstructure. One can only imagine what the view from the stars to the horizon would be like at night as you drift off to sleep in your futuristic floating palace. 500 individual pieces of specially formed reinforced glass were required to complete the ship's superstructure. It was one of the program's most challenging aspects.

pierrejean-design.com

pierrejean-design.com The owner's suite looks like it belongs on a starship instead of a yacht. It is totally self-contained and private. A Forward door opens up to private deck overlooking the bow.

We also don't know exactly what the ship is capable of performance wise. The Kortenaer class were fast ships, able to hit speeds in excess of 30 knots. But even though her powerplant was swapped for a far less powerful, but more conventional system, the ship's slender hull should provide high efficiency and good stability. Many state that the vessel can do 26 knots and cruise efficiently just a few knots slower on a pair of MTU 10,500hp diesel engines. Her original powerplant configuration was way more powerful, but she would have had a much larger displacement while serving as a surface combatant. In fact, Yaz's superstructure is made almost entirely out of lightweight composite materials which helps dramatically in keeping weight down to improve performance. You can read all about this huge and unprecedented undertaking here and in this downloadable powerpoint. It's even claimed that the ship, in its new configuration, can be considered 'green'—everything is relative in the superyacht world. If she really can hit nearly her original design speed on a fraction of the horsepower, this claim is true.

JFCI Composites The ship's steel hull is mated to an all-composite superstructure.

The frigate's hull was upgraded with bow thrusters and stabilizers during her transformation from Al Emirat to Yaz. The photo below shows these features and it also gives us a better idea of just how gorgeous the hull on this ship really is. No wonder they used it as the foundation for an exotic and highly expensive superyacht.

pierrejean-design.com

Here's another really nice view of the vessel's remodeled hull-form. Yaz, which one would assume is named after its owner's son who has the same name, may not appeal to everyone aesthetically speaking, but I think it is absolutely gorgeous. Just doing something creative and different while still delivering a strong set of features and an overall logical design is no easy task. Combine that with recycling an old frigate's hull with the goal of achieving extreme performance, not to mention pulling off something that works both visually and operationally, and you have one amazing accomplishment that differentiates itself from pretty much everything else in the superyacht world. And what's so cool about Yaz's design is that the hull-form really does pull the entire concept together and doesn't conflict with the ship's ultra-modern superstructure. For how bulbous it is in some places it still looks like it was born to slice through the seas. With what was likely a very steep learning curve building Yaz now under ADMShipyards' belt, one would think her sister hull, the ex-Abu Dhabi, would be under construction. Somewhat different in design, this project is named Swift135. Here are the renderings of it:

pierrejean-design.com

pierrejean-design.com

pierrejean-design.com

The design represents a more of a conventional affair than its dolphin-like sister ship. Overall it appears less sleek and is more of a modern take on classical yacht designs. It also doesn't feature the added streamlined stern extension found on Yaz. But at this time it isn't clear if the project is underway or if it is still even a possibility. In satellite imagery, the last date we see the stripped hull of the proposed Swift131 outside ADMShipyards is in late October 2013. Since then it is nowhere in the vicinity. It could have been towed somewhere for prep work, but it has been half a decade and still no sign of it at the shipyards.

Google Earth The last satellite image we see the second frigate hull in at ADMShipyards in Abu Dhabi.

We don't know how much Yaz actually cost. A royal customer supporting the country's own shipbuilding enterprise is one thing, but finding an external customer for a follow-on project may have proven to be a challenge. And a buyer spending hundreds of millions of dollars may just want something totally new regardless of the advantages of converting an existing hull. It's also possible that the second hull could be under construction elsewhere too. We just don't know at this time. Currently, Yaz is the world's 11th largest yacht and when it comes to luxury and amenities, it delivers. It features a pool, spa, multiple saloons and entertainment areas, as well as all the other toys you would find on a top superyacht. Yaz also has an oversized helipad that is usually occupied by a white AW139 and its entertainment system is supposedly the most advanced in the world.

pierrejean-design.com

She sails with a complement of about 60 and can accommodate as many guests. Due to her frigate hull, she is adept at quickly crossing oceans but seems to usually spend her time in the Mediterranean with visits to the Persian Gulf. So there you have it, the truly one of kind Yaz— a highly innovative design that blends the old with the new and the tactical with the incredibly impractical, all in a beautifully seamless and effective manner. Contact the author: Tyler@thedrive.com