DRDO tests tech for stealthier submarines

10 Mar 2021 Editorial Team

The Defence Research and Development Organisation (DRDO) conducted the final development test of Air Independent Propulsion (AIP) in Mumbai.

The AIP technology allows a submarine to be submerged for longer periods underwater and makes the sub surface platform more deadly by making it quieter than a nuclear submarine.

The Indian Navy is now planning to retrofit all its Kalvari class non nuclear attack submarines with AIP during their first upgrade, expected around 2023. The 1,615 tonne Kalvari class submarine is being built by Mazagon Dockyards Ltd (MDL) in collaboration with the French Naval Group and is based on Scorpene design.

India now has the AIP technology along with the US, France, China, the UK. The DRDO's AIP technology is based on a Phosphoric Acid Fuel Cell, and the last two Kalvari class submarines will be powered by it. The AIP design was tested on land in Mumbai.

The AIP or marine propulsion technology allows non nuclear submarines to operate without access to atmospheric oxygen (through snorkel or surfacing) and augments the diesel-electric propulsion system of attack submarines. This means that AIP fitted submarines do not have to surface for charging their batteries and remain underwater for long periods. The AIP is retrofitted into existing submarine hulls by adding an additional hull section. The AIP equipped submarines are identified as SSP, while classic diesel attack submarines carry the SSK classification.

While the nuclear submarine generates noise due to the ship's reactor constantly pumping coolant to maintain the engine's temperatures, the AIP equipped submarine maintains a lethal silence. The new technology will allow Indian submarines to take advantage of internal refraction in equatorial waters due to temperature differences on the surface and within the ocean.

Image Source

4th Indian Cement Review Conference 2021

17-18 March

Click for event info

The Defence Research and Development Organisation (DRDO) conducted the final development test of Air Independent Propulsion (AIP) in Mumbai. The AIP technology allows a submarine to be submerged for longer periods underwater and makes the sub surface platform more deadly by making it quieter than a nuclear submarine. The Indian Navy is now planning to retrofit all its Kalvari class non nuclear attack submarines with AIP during their first upgrade, expected around 2023. The 1,615 tonne Kalvari class submarine is being built by Mazagon Dockyards Ltd (MDL) in collaboration with the French Naval Group and is based on Scorpene design. India now has the AIP technology along with the US, France, China, the UK. The DRDO's AIP technology is based on a Phosphoric Acid Fuel Cell, and the last two Kalvari class submarines will be powered by it. The AIP design was tested on land in Mumbai. The AIP or marine propulsion technology allows non nuclear submarines to operate without access to atmospheric oxygen (through snorkel or surfacing) and augments the diesel-electric propulsion system of attack submarines. This means that AIP fitted submarines do not have to surface for charging their batteries and remain underwater for long periods. The AIP is retrofitted into existing submarine hulls by adding an additional hull section. The AIP equipped submarines are identified as SSP, while classic diesel attack submarines carry the SSK classification. While the nuclear submarine generates noise due to the ship's reactor constantly pumping coolant to maintain the engine's temperatures, the AIP equipped submarine maintains a lethal silence. The new technology will allow Indian submarines to take advantage of internal refraction in equatorial waters due to temperature differences on the surface and within the ocean. Image Source4th Indian Cement Review Conference 202117-18 March Click for event info

Infrastructure Urban

02 Jun 2026

VECV Sales Rise 7.8 Per Cent In May 2026

VE Commercial Vehicles recorded sales of 7,978 units in May 2026, compared to 7,401 units in May 2025, registering growth of 7.8 per cent. This included 7,789 units from the Eicher brand and 189 units from the Volvo brand.Eicher branded trucks and buses reported sales of 7,789 units during the month, up 7.3 per cent from 7,258 units a year earlier. In the domestic commercial vehicle market, Eicher sales rose 9.1 per cent to 7,375 units from 6,758 units in May 2025.Exports declined 17.2 per cent to 414 units from 500 units in the corresponding month last year. Volvo Trucks and Volvo Buses recor..

Infrastructure Urban

02 Jun 2026

Table Space Strengthens DESYN Leadership Team

Table Space has announced strategic leadership appointments within DESYN, its integrated Design and Build business, as it looks to strengthen operations across key enterprise and GCC markets in India. DESYN was launched as a strategic extension of Table Space’s workspace solutions portfolio to meet rising demand for agile, high-quality and rapidly deployable enterprise workspaces.Shruti Ookabhoy has joined DESYN as Executive Director and will lead the Design vertical, focusing on design capability, operational excellence and team development across markets. She brings over 22 years of experi..

Infrastructure Transport

02 Jun 2026

Concord Associate Bags Rs 2.79 Bn Kavach Order

Concord Control Systems said its associate company, Progota India, has received a Rs 2.79 bn domestic order from Indian Railways for the supply, installation, testing and commissioning of on-board Kavach 4.0 loco equipment.The order is scheduled for execution within 12 months and strengthens Concord’s role in India’s railway safety and signalling ecosystem. Kavach is India’s indigenous automatic train protection system, designed to improve operational safety by helping prevent signal passing at danger and reducing collision risks.Gaurav Lath, Joint Managing Director, Concord Control Syst..