IRIA News

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Brazil marked a series of major milestones in its Submarine Development Program (PROSUB) as it received its third Scorpene-class submarine, while advancing construction on the fourth unit of the same class.

The receiving ceremony of the third Scorpene-class submarine took place at the Itaguai naval base. During the same ceremony, the fourth submarine in the series, the Almirante Karam (S43), was launched, marking the next step in the Navy’s conventional fleet expansion.

The first two units, Riachuelo (S40) and Humaita (S41), were commissioned in September 2022 and January 2024, respectively.

Both milestones reflect continued progress under PROSUB, a long-term partnership between Brazil and France’s Naval Group. The Scorpene submarines are designed for anti-surface warfare, anti-submarine missions, and special operations, offering exceptional acoustic performance, endurance, and robust combat capabilities in both deep and shallow waters.

Naval Group, which is supporting construction under a comprehensive Technology Transfer agreement, said the achievements demonstrate Brazil’s growing technological maturity. “More than delivering submarines, our mission is to build, together with Brazil, a long-term technological and industrial legacy,” said Pierre Eric Pommellet, Chairman and CEO of Naval Group.

Construction of First Nuclear Submarine

Alongside the delivery and launch of the conventional submarines, the Navy confirmed that it has entered the most sensitive phase of the PROSUB program with the full-scale construction of the country’s first nuclear-powered submarine, the Alvaro Alberto.

The announcement was made during an event at the Itaguai Naval Complex, where the Navy showcased the Almirante Karam and held a weapons demonstration with the Tonelero.

This new stage begins the structural work on the nuclear vessel, starting with the stern section at the Itaguai shipyard. According to the Navy, the technologies involved in this phase are held by only five nations: China, Russia, France, the United States, and the United Kingdom, making Brazil the first country in the Southern Hemisphere to design and build a nuclear submarine.

Officials describe the transition to the nuclear phase as the most important moment of PROSUB, marking the shift from conventional development to the program’s ultimate strategic objective.

Why Alvaro Alberto Matters for Brazil

Expected to enter service in 2034, the Alvaro Alberto will use a pressurized water reactor, the most widely adopted and considered highly safe for military propulsion. Engineers are now focused on the electromechanical and control systems that will form the technological core of the submarine.

Nuclear propulsion will allow the submarine to operate submerged for long periods without refueling, significantly expanding Brazil’s patrol, surveillance, and deterrence capabilities. The Navy also highlights that mastering nuclear-submarine technology reduces reliance on foreign suppliers and supports the growth of Brazil’s defense industry, potentially opening doors for future exports.

Brazil’s Rising Maritime Profile

The progress on both the Scorpene fleet and the nuclear program signals Brazil’s intent to elevate its maritime influence. The Álvaro Alberto is named after one of the key figures of Brazil’s nuclear program, symbolizing decades of national investment in technological sovereignty and defense innovation.

For the Navy, PROSUB represents more than new vessels. It has generated highly skilled jobs, strengthened the domestic industrial base, and established a long-term partnership structure that integrates Brazilian companies into global supply chains.

Naval Group has trained Brazilian welders, electricians, metal formers, and plumbers in France, enabling the shipyard to independently master advanced submarine-construction processes.

As the third submarine enters service, the fourth moves forward, and the nuclear project advances, Brazil positions itself as a rising naval power. Officials say these steps will have direct impacts on national security and help define the country’s international role in the maritime domain for decades to come.