HAL has proposed that the platform needs to have an all-up weight of 13 metric tons, a maximum speed of 275-km/h and a service ceiling of 22,000 ft. The Indian military wants the helicopter to have a payload capacity of 3,500-kg and range of 500-km at sea level. The IMRH platform is to sport a five-blade composite main rotor with a four-bladed composite tail rotor, twin turboshaft engines with dual full authority digital engine controls. The powerplants would be required to have a 30-minute dry-run capable transmission system. All IMRHs will have glass cockpits — using equipment from Halbit Systems, DARE and Samtel.
The bid is stuck, however, at the EoI stage, with four companies wondering what is happening. Companies that have responded to HAL’s invitation include Eurocopter (EC725 Caracal), Sikorsky (S-92A), Agusta-Westland (AW101) and Mil (Mi-17-IV).
Officially the IMRH mission spectrum includes troop movement, high-altitude air maintenance, offshore operations, heliborne and amphibious assault operations, anti-submarine warfare and anti-surface warfare. An armed gunship version is also expected to be concurrently developed. Other proposed variants include civil transport, VVIP transport, and air-ambulance.