The programme was considerably delayed due to funding issues and the Brazilian Verolme yard's insolvency in 1991 which forced Júlio de Noronha and Frontin to be completed by Arsenal da Marinha.

The vessels in the class are powered by a combined diesel or gas (CODOG) system composed of one GE LM 2500 gas turbine rated at 20,500 kilowatts (27,500 hp) and two MTU 16 V 396 TB 94 diesel engines rated at 5,800 kW (7,800 bhp) turning two shafts.

[2] The class is armed with four Exocet surface-to-surface missiles (SSM) placed centrally and a Mk 8 114 mm (4.5 in) gun situated forward.

They are equipped with two Bofors 40 mm (1.6 in)/70 anti-aircraft (AA) guns in a twin mount atop the aft superstructure.

[2] During the design phase, a Vulcan Phalanx close-in weapon system (CIWS) was intended for the stern.

However, the class was considered top heavy and the idea was scrapped with the possibility of a surface-to-air missile mount in place instead.

[1] For sensors the Inhaúma class are fitted with Plessey AWS-4, Kelvin Hughes Type 1007 and Selenia Orion RTN 10X radar and Krupp Atlas ASO4 Mod 2 sonar.

However, while the second pair were under construction, the shipyard went bankrupt in 1991 and the incomplete hulls were taken to the Arsenal de Marinha for completion.

In 1994, a second improved version of the class comprising six ships was ordered by the Brazilian government from the Arsenal de Marinha.

[7] On 17 April 2016, ex-Fortin was sunk in the Atlantic Ocean between Rio de Janeiro and Vitória in a naval exercise involving several warships of the Brazilian Navy.