Over the last 2 decades, HAL has strongly placed its foot in the Light Helicopter category with the success story of the Advanced Light Helicopter Dhruv. More recently, with competitive products like the Light Utility Helicopter (LUH) & the Light Combat Helicopter (LCH), HAL has gained significant expertise in designing & developing helicopters upto a gross weight of 6 tons. With this experience, now HAL is graduating to developing a medium lift multirole helicopter.
The project is called the Indian Multi Role Helicopter or IMRH. Now the IMRH is just not an extrapolated concept from the light category & HAL didn’t just design only because they could, there is more to it. Currently, in Asian (including India) & African markets, the role of medium lift helicopters is fulfilled by the ubiquitous Mi-8/Mi-17. Though the Mi-8 is an old helicopter & is mostly phased out of service in most nations, the Mi-17 & its latest variants are comparatively new & are in military & civil service with more than 100 countries. These Russian machines are simple, robust & magnificent workhorses for even the most demanding tasks. The cherry on the cake is that they are extremely cheap to buy & operate, hence the major market share of medium lift helicopters is dominated by the Mi-8/Mi-17s.
Now HAL decided to take part in the game. There are more than 5,000 Mi17s flying in the world today which have been operational for quite a while. Considering that the Mi-17 has a service life of 25 years, hundreds of helicopters will be due for replacement every year after 2030. What that means is these 100-odd countries will be in the market for a medium lift helicopters in the next 9-10 years & that’s exactly when HAL is preparing to pitch the IMRH in the world market, as a successor of the Mi-17.
Things aren’t very rosy there as Kazan Helicopters, the manufacturer of the Mi-17 has already developed the Mi-38 as the replacement of the Mi-17. We’ll know where the Indian helicopter stands against the Mi-17 & Mi-38 once our prototypes start flying in a couple of years from now, but where the competitive advantage lies with India is superior technology available in our rotary wing aircrafts, better maintainability along with 15-20% lower cost of acquisition. The cornerstone to success of the IMRH is the fact that the helicopter is “benchmarked” against the top five current heavy-class rotorcrafts: Airbus Helicopters H225M, Leonardo Helicopters AW101, NH Industries NH90, Sikorsky S-92 & the Mi-17. This essentially means that the most useful & state of the art features from all these will be incorporated in IMRH.
Recently, during Aero India 2021 in Bengaluru, HAL conducted a seminar in which a lot of details about the IMRH were made public. According to the spokesperson, the IMRH is going to be a twin engine helicopter with a MTOW (Max take-off weight) of 13 tons & a capacity to carry 36 troops in high density configuration. Featuring a five-blade main rotor and four-blade, bearingless tail rotor, composite fuselage, and glass cockpit, the IMRH will have 75% domestic content. The primary exception will be the helicopter’s 2,800 shaft horsepower engines, which will be sourced from a western manufacturer (mostly Safran). The payload at sea level is said to be 4 tons, decreasing all the way to 1.5 tons at 13,000 feet as the air density is far lesser at those altitudes. These numbers are pretty same as Mi-17 payload figures.
The seminar also revealed the dimensions of the helicopter. The airframe will be 25.16 meter long (rotors rotating), 4.74 meter wide with a total height of 5.11 meter (vs 5.65 m of Mi-17). The fuselage itself will be 19.8 meter long (vs 18.4 m for Mi-17). The rotor diameter is 21.2 meter which is almost the same as the Mi-17. The internal cargo/ passenger space will be 5.4 m long, 2.34 m wide & 1.8 m tall. This means that there is enough room to stand inside the cabin even with helmet on. The cabin can hold a light vehicle such as Gypsy which can ingress & egress through the ramp provided at the back.
Apart from a cargo/utility configuration, the airframe will also have a gunship configuration with 1,600 kg of weapon integration capability. Each stub wing on either side will be rated 500 kg on the inboard station and 300 kg on the outboard. Range is predicted to be 800 km, with a cruise speed of 260 kmph & top speed of 300kmph. The service ceiling will be 6,500 meter which essentially means that the IMRH will be able to operate in high altitude regions. The aircraft will be able to take off from Leh airfield with a significant cargo/troops load. Since the IMRH will be operating in sensitive areas, it’ll have an Electronic Warfare & self-protection suite to protect it from enemy’s surface to air missiles.
The cockpit will feature a glass cockpit configuration with large area displays & artificial intelligence to lessen the crew workload. At the controls front, there will be a 4 axis digital automatic flight control system. The airframe will be a modular airframe, meaning it’ll be like a jigsaw puzzle with different modules fitting together to form a structure. The HAL spokesperson confirmed that they are looking for private sector participation in the manufacture of the airframe. He also confirmed that they are looking at the potential vendors for various LRUs (Line Replaceable Units).
The Indian armed forces will have a significant requirement of such a helicopter. Currently the Army Aviation Corps of the Indian Army doesn’t operate any medium lift helicopter. The medium lift capability is provided by the Indian Air Force. Going forward, the Army Aviation Corps will have their own medium lift helicopter. The projected requirement for the Indian armed forces is 200 aircraft for the Indian Air force, 100 for the Indian Army (Army Aviation Corps) & 14 for the Indian Navy, taking the total to 314 helicopters. Apart from this, the IMRH can also be converted into a VVIP helicopter & will have demand from civilian market in India too.
HAL spokesperson, in the seminar, emphasised on the fact that they are pretty serious to pitch the IMRH in the global competition of a medium lift multirole helicopter. Whether or not the Armed Forces showcase a similar magnitude of confidence in the platform will decide its actual fate. No foreign country wants to buy an equipment if the seller’s own military is not using it. If the IAF, Army & Navy decides to give large orders, then it paves the way for this helicopter to emerge as a serious competition in the global tender for medium weight category.
Considering the stellar past performance of the Rotary wing design team of HAL in designing & developing the ALH, LUH & the LCH, we can now safely assume that HAL will again give the nation another spectacular product in the IDDM (Indigenously Designed, Developed & Manufactured) category.
For the HAL seminar link at Aero India 2021: Click here.
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