At the end of August, the presentation of the promising Russian light single-engine coaxial helicopter ATM-121 went unnoticed in the media. The machine was demonstrated at Heliport Istra Helicopter Centre near Moscow, where Robinson R44/R66, Airbus H125/H130 and other light single-engine machines are based, Telegram-channel ё-Prom – Import substitution of industry reported.
The ATM-121 project is being handled by AeroTechMash (ATM LLC), which is a subsidiary of Aeroelectromash JSC (“AEM”), a manufacturer of electrical equipment and automatic control systems for domestic aircraft. ATM-121 is not AEM’s first project in helicopter construction: at HeliRussia 2019, the company, together with Kumertau-based Rotor Design Bureau, presented the R-34 ultra-light coaxial helicopter.
The ATM-121 is being developed by a design team led by chief designer Shamil Suleymanov, previously chief designer of the Kamov Design Bureau and the Ka-32. ATM LLC is headed by ex-Aero-Kamov chief and director of the Ka-32 Helicopter and its Modifications programme at Mil and Kamov NCV Sergey Astapenko, who also worked at Sukhoi Civil Aircraft, as did designer Anatoly Mezhevov.
The comfortable cabin with panoramic view of the ATM-121 helicopter is designed for one pilot and four passengers. The maximum take-off weight is 1350 kilograms. The flight range is 650 kilometres, speed – 210 km/h. Practical flight altitude is 3000 metres, maximum flight duration is up to 5 hours. The helicopter can be operated at temperatures from -45 to +40 degrees centigrade.
The rotary piston engine AN3-250VK with an output of 250 hp is used as a power plant. Powered by aviation paraffin, the engine provides fuel efficiency unattainable for gas turbine engines. The helicopter is designed in accordance with the requirements of the NLG-27 safety standards. Elaborate and optimised internal volumes have made it possible to harmoniously place a large cargo compartment with a volume of more than 1.15 m³ in the tail section of the cockpit, which can freely accommodate up to six standard-sized suitcases or cargo weighing up to 400 kg. Access to the cargo compartment is provided through wide rear flaps.
According to the developers, the ATM-121 is capable of performing a wide range of tasks: from passenger and cargo transport, surveillance, law enforcement, corporate or VIP transport to rescue and other special tasks. The coaxial design of the main rotors provides easy and reliable control and makes the helicopter ideal both for initial pilot training and for missions in difficult conditions and when flying in mountainous terrain. The three-blade upper and lower main rotors, the optimised peripheral speed of the main rotor blades and the specially shaped blade tips reduce vibrations and noise levels.
