India’s Defence Research and Development Organisation (DRDO) is developing a land-based prototype for air independent propulsion (AIP) technology to reduce submarine vulnerability, defence minister AK Antony revealed.

The technology project is being supported by the Naval Materials Research Laboratory (NMRL) and is expected to be demonstrated by 2015, Antony added.

Meanwhile, the Indian Navy is preparing to float the request for proposals to procure six air independent propulsion (AIP) submarines that is likely to be issued to DCNS, HDW and Amur Design Bureau.

The $11bn procurement was approved by the Defence Ministry last year and is expected to be floated by the year-end or in early 2012.