This high-performance aluminium interceptor for Spain's Guardia Civil Maritime Service fleet was designed specifically for rapid-response patrols in the busy Strait of Gibraltar off Cadiz and Huelva provinces.
Part of an eight-vessel series, Rio Guadalmedina offers exceptional speed and agility, with a maximum speed of over 60 knots, the ability to stop in roughly two boat lengths, and to turn around in less than two lengths, all while maintaining stability.
The hull is optimised for extreme acceleration without sacrificing safety, habitability, or longevity, and was designed for over 20 years of service and with ramming resistance.
This interceptor excels at chasing criminal and other adversarial craft in anti-drug, border control, and surveillance missions, combining performance with practical, durable design.
"Rio Guadalmedina represents a genuine step-change in high-speed aluminium interceptors," Javier Rasilla, Managing Director at Aister, told Baird Maritime. "What truly sets her apart is the combination of extreme speed—exceeding 60 knots—with an agility that is almost unheard of for an 18-metre vessel.
"Thanks to her hull design and waterjet propulsion, she can stop in about two boat lengths and execute controlled turns in less than two. It is a unique package that offers top-level acceleration, stability, and an operational range of almost 500 nautical miles at cruising speed without compromising crew protection."
Rasilla added that fabricating an 18-metre high-performance hull to such tight tolerances is always a technical challenge, as weld quality and structural alignment are critical when the goal is to combine strength with weight control. The integration of the two engines with the waterjets also required rigorous coordination.
"The main lesson reinforced was the value of early collaboration with suppliers," said Rasilla. "By working closely with the manufacturers of the engines, jets, and electronics from the outset, along with a meticulous development of the equipment and systems layout during the detailed engineering phase, we achieved a design that allows, for example, a complete re-engining in a single day. We have already applied this knowledge to other projects at the shipyard."
Rio Guadalmedina was built to achieve high speeds, which Rasilla said is a requirement among a growing number of clients along with the ability to withstand aggressive ramming attempts and a service life exceeding 20 years.
"Beyond environmental regulations, there is a massive push towards survivability and lifecycle efficiency. Additionally, the need for resilient electronics is growing, and our systems are now designed to maintain situational awareness even in contested or degraded communications environments through redundant NMEA-2000 networking and satellite backups."
The delivery of Rio Guadalmedina was just one of Aister's many accomplishments in 2025, which Rasilla regarded as a landmark year for the company.
"Compared to previous years, we are observing a shift from 'standard' patrol boats toward highly specialised interceptors," he told Baird Maritime. "We are very optimistic, especially with the unveiling of a new combat boat, which expands our reach into the defense sector.
"Our orderbook reflects a growing global demand for speed combined with tactical versatility. Our strong ability to provide customised solutions tailored to our clients' needs allows us to operate with confidence in markets worldwide."
The speed and tactical versatility Rasilla observed among global customers are among the key trends that he believes will shape the future of maritime security.
"Demand is shifting towards multi-mission interceptors that allow for the integration of ballistic protection and remote-controlled weapon stations on extremely versatile platforms. In this context, speed has become a baseline requirement, as the market now demands extraordinary agility; critical capabilities such as stopping or turning in just two boat lengths require active control systems and hull interceptors to ensure rapid transitions to planing without compromising pilot visibility."
Rasilla explained that this technical sophistication is backed by the structural resilience of aluminium, which allows for a balance between the lightness needed for high performance and a robustness capable of withstanding tactical ramming manoeuvres and a service life exceeding 20 years.
"Ultimately, efficiency is measured today by operational availability; the trend is moving towards modular designs that simplify maintenance, allowing for full re-engining in a single day and 5,000-hour intervals between overhauls. All of this is complemented by double-redundancy electronics and advanced connectivity, which are vital to ensuring mission success even in hostile environments or under degraded communications."
As for the workboat industries of Spain and Europe, Rasilla believes demand for low-emission vessels will continue alongside vessels built to have service lives that are as long as possible.
"When analyzing the trajectory of the European and Spanish workboat industries, it is evident that we are consolidating our position as a global benchmark in the development of high-efficiency platforms with extremely optimised lifecycle costs," he told Baird Maritime.
"The future of the sector is no longer conceivable without the full integration of IMO Tier III regulations, which is driving an evolution toward ultra-low emission engines and advanced hydrodynamic designs that drastically reduce the carbon footprint, meeting the increasingly stringent sustainability demands of European ports."
Rasilla believes this technical evolution allows Aister to specialise in high value-added niches, such as offshore windfarm crewboats, pilot boats, or vessels for high-intensity port services, where the durability of aluminum offers great resistance.
"In this scenario, digitalisation plays a critical role; we are no longer just building hulls, but monitored systems that enable predictive maintenance through remote 'health' tracking of the vessel. This ensures that the boat remains operational for the maximum number of hours possible, avoiding unscheduled downtime that would otherwise hinder the owner's profitability.
"Ultimately, all this technology converges in a decisive commitment to advanced ergonomics, where design focuses on the operator's well-being to mitigate fatigue during extended missions. To achieve this, we are integrating intelligent bridges and the latest generation of shock absorption systems, transforming the workboat into a tool that is not only more productive but also much safer and more human-centric."
For a list of the 2025 "Best Of" award winners, please click here.
