HAL–Safran to jointly develop ‘Aravalli’ engine for multi-role helicopters
Hindustan Aeronautics Limited (HAL) and Safran Helicopter Engines have formalised a 50:50 joint venture, SAFHAL Helicopter Engines Private Limited, to jointly design, develop, manufacture, and support a new helicopter engine named "Aravalli."
The engine falls in the 3,500–4,000 shaft horsepower (shp) class and is intended to power the 13-tonne Indian Multi-Role Helicopter (IMRH) and its naval variant, the Deck-Based Multi-Role Helicopter (DBMRH).
Manufacturing is planned at a facility in Tumakuru, Karnataka, with design and development targeted for completion by 2032–33.
The programme marks the first time a high-power helicopter engine has been designed and developed in India, giving HAL access to high-pressure compressor, power turbine, fuel and oil system, and accessory gearbox technologies.
The effort is aimed at reducing continued dependence on the Russian-origin Mi-17 family for medium-lift helicopter operations.
Aero-Engine Indigenization — Lessons from the Kaveri Programme
India's earlier attempt at a fully indigenous jet engine, the Kaveri, illustrates why high-power gas turbine development is treated as one of the hardest technological frontiers in aerospace, and why the Aravalli programme has been structured as a joint venture rather than a standalone indigenous effort.
Key Details
- The Kaveri engine was sanctioned in 1989 and developed by the Gas Turbine Research Establishment (GTRE), a DRDO laboratory, as the intended powerplant for the Tejas Light Combat Aircraft.
- It fell short of its thrust target (around 73 kN wet thrust achieved against an 81 kN requirement) and was formally de-linked from the Tejas programme in 2008, after which Tejas variants adopted the American GE F404/F414 engines instead.
- Persistent problems included thrust deficiency, turbine blade overheating, and a lack of access to advanced single-crystal blade materials and testing infrastructure.
- A non-afterburning derivative of Kaveri has since been repurposed for the Ghatak unmanned combat aerial vehicle programme.
Aravalli avoids the "go-alone" trap that constrained Kaveri by pairing HAL with an established engine manufacturer (Safran) through a joint-venture structure that transfers core hot-section and compressor technology, rather than attempting a purely domestic design from a standing start.
The Joint-Venture Route for Defence Technology Transfer
Government-to-government or company-to-company joint ventures are one of the few mechanisms that give India access to closely-guarded "core" defence technologies — such as jet-engine hot sections or missile propulsion — that are rarely licensed through ordinary import contracts.
Key Details
- The BrahMos supersonic cruise missile programme is India's benchmark example of this route: BrahMos Aerospace was formed after an Inter-Governmental Agreement signed in Moscow on 12 February 1998, as a joint venture between DRDO and Russia's NPO Mashinostroyeniya, with India holding roughly 50.5% and Russia 49.5% of the equity.
- That structure gave India full design, manufacturing, and export rights to the missile, rather than a licensed-production arrangement.
- SAFHAL follows a comparable logic for helicopter engines: a dedicated 50:50 joint-venture company, rather than a technology-transfer licence, is used to co-own the resulting engine design.
The Aravalli programme extends the BrahMos-style joint-venture template — proven for missile propulsion — into the aero-engine domain, aimed at giving HAL co-ownership of a high-power turboshaft design rather than mere manufacturing rights.
IMRH/DBMRH and India's Medium-Lift Helicopter Modernisation
The Indian Multi-Role Helicopter is the platform around which the Aravalli engine is being built, and its progress is directly tied to closing a long-standing capability gap in India's rotary-wing fleet.
Key Details
- IMRH is a 13-tonne class helicopter intended to replace over 240 ageing Mi-17/Mi-8 helicopters in service with the armed forces; HAL estimates a total requirement of 300-plus rotorcraft of this class.
- A dedicated Helicopter Factory has been set up at Tumakuru to build rotorcraft in the 3-tonne to 12-tonne category.
- India's other indigenous helicopters occupy different weight classes: the Advanced Light Helicopter Dhruv (around 5.5 tonnes, utility role), the Light Combat Helicopter Prachand (around 5.8 tonnes, attack role, inducted 2022), and the Light Utility Helicopter (around 3 tonnes) — none of which covers the medium-lift segment that Mi-17s currently occupy.
- DBMRH is the navalised variant of the same 13-tonne design, intended for deck operations from Indian Navy ships.
Without an engine in the 3,500–4,000 shp class, the IMRH/DBMRH programme cannot proceed to flight testing or production; the Aravalli engine is therefore the critical enabling technology for closing India's medium-lift helicopter gap.
Turboshaft Engines — Basic Operating Principle
Understanding how a turboshaft engine differs from a turbojet or turbofan clarifies what "3,500–4,000 shp" actually measures and why this project is technologically distinct from fighter-jet engine programmes like Kaveri.
Key Details
- A turboshaft engine is a gas turbine optimised to deliver rotational shaft power — via a gearbox — to a helicopter's main and tail rotors, rather than producing forward thrust directly as a turbojet or turbofan does.
- Turboshaft output is rated in shaft horsepower (shp), unlike turbojet/turbofan output, which is rated in thrust (kilonewtons, kN).
- Core subsystems include the compressor (raises intake air pressure), combustor, gas-generator turbine, and a separate free power turbine that drives the output shaft — the same subsystem categories (compressor, power turbine, gearbox) referenced for the Aravalli programme.
The "high-pressure compressor, power turbine systems, accessory gearbox" technologies HAL will gain access to under SAFHAL correspond precisely to these turboshaft subsystems, distinguishing this programme's technical scope from a fighter-engine (turbofan) development effort.
- SAFHAL Helicopter Engines Private Limited: 50:50 joint venture between HAL and Safran Helicopter Engines
- Aravalli engine class: 3,500–4,000 shaft horsepower (shp)
- Target platforms: Indian Multi-Role Helicopter (IMRH, 13-tonne) and Deck-Based Multi-Role Helicopter (DBMRH, naval variant)
- Manufacturing location: Tumakuru, Karnataka
- Design and development completion target: 2032–33
- Current medium-lift dependency: Russian-origin Mi-17 family, over 240 helicopters in service
- Comparison — Kaveri engine: sanctioned 1989, de-linked from Tejas in 2008 after achieving ~73 kN against an 81 kN thrust target