Radar: Surface search I-band The Heroine class are a variant of the Type 209 diesel-electric attack submarine developed by Howaldtswerke-Deutsche Werft (HDW) of Germany, currently in service with the South African Navy.

South Africa placed a contract for three Type 209 1400-Mod submarines in July 2000 on Howaldtswerke-Deutsche Werft (HDW) and Thyssen Nordseewerke.

The Armscor annual report to parliament indicated that should the refits not take place, the submarine capability would not available after FY2022/23.

Funding in the amount of R189 million had reportedly been made available to ensure the completion of the refit during the 2023/24 financial year.

"[5] As of April 2023, Manthatisi had completed a Docking and Essential Defect (DED) maintenance period and was undergoing post-maintenance trials.

Queen Modjadji was undergoing preservation and pre-refit planning activities, in preparation for a refit.

[12] The OMS-100 mast integrates an optronic sensor with a high-definition resolution colour TV camera and third generation thermal imager.

South Africa did not exercise the option of purchasing a 'clip-on' towed array sonar based on advice from existing users that the system is clumsy and would prove impractical in South Africa's envisaged operational context.

An internal audit of Ferrostaal by American-based law firm Debevoise and Plimpton, who was hired after the German Public Prosecutions Authority arrested of one of its board members in 2010, reportedly places the amount paid in bribes at R300 million, or over $40 million.

[14] The submarines of the Heroine class are primarily used to patrol and detect illegal fishermen in the territorial waters of South Africa.