Sigma-class Corvette

The Sigma-class corvette is a Dutch-built family of modular naval vessels, of corvette size. The basic design of the Sigma Patrol Series can vary as the hull segments are designed as components. Ships can vary in the number of hull segments and in the order in which they are placed. Sigma stands for Ship Integrated Geometrical Modularity Approach. The ship's main dimensions are named in the types itself, SIGMA 9113 stands for 91 metres (298 ft 7 in) long and with a beam of 13 metres (42 ft 8 in). Likewise, the SIGMA 10513, is 105 metres (344 ft 6 in) in length with a beam of 13 meters.

The design was derived from the earlier High Speed Displacement hull form by MARIN Teknikk AS in the 1970s.

Brazil

 * NRB Unnamed - planned for construction
 * NRB Unnamed - planned for construction
 * NRB Unnamed - planned for construction
 * NRB Unnamed - planned for construction

Sigma 9113

 * KRI Diponegoro (365)
 * KRI Sultan Hasanuddin (366)
 * KRI Sultan Iskandar Muda (367)
 * KRI Frans Kaisiepo (358)

Sigma 10514

 * KRI Raden Eddy Martadinata (331)
 * KRI I Gusti Ngurah Rai (332)

Mexico

 * ARM Reformador - under construction
 * ARM Unnamed - planned for construction
 * ARM Unnamed - planned for construction
 * ARM Unnamed - planned for construction
 * ARM Unnamed - planned for construction
 * ARM Unnamed - planned for construction

Morocco

 * Tarik Ben Ziyad (613)
 * Sultan Moulay Ismail (614)
 * Allal Ben Abdellah (615)

Romania

 * Unnamed - under construction
 * Unnamed - under construction
 * Unnamed - under construction
 * Unnamed - under construction

Vietnam

 * Trần Khánh Dư (HQ-017) - under construction
 * Phạm Ngũ Lão (HQ-018) - under construction
 * Nguyen Van Tru (HQ-019) - under construction
 * Trần Nhật Duật (HQ-020) - under construction