Turboshaft hearts and heart
In the first part of the story, it was mentioned that the Mi-38 made its first flight on Pratt & Whitney Canada PW-127T / S engines, and this was largely supposed to ensure that the aircraft entered the international market. But times have changed, and within the framework of the state program of import substitution, as well as under the influence of high sanctions risks, the domestic TV7-117V is the main engine for the Mi-38 family helicopters.
In 2008, the Canadian Pratt & Whitney, due to the lack of permission to export its motors to Russia, was forced to abandon further cooperation with Russia. Therefore, I had to pay attention to the turboshaft version of the aircraft turboprop TV7-117SM from JSC "UEC-Klimov" and MMP im. V. V. Chernyshev, dating back to the 80s.
Here you can make a digression and ask: what would have happened to the domestic aviation engine building, if not for various Western sanctions, bans and restrictions? Could, in particular, survive in UEC-Klimov from the United Engine Corporation in the event of the widespread replacement of aircraft engines with Western counterparts?
The development of the TV7-117V engine started on December 1, 1989 and was originally aimed at the Mi-38, but then there was an era of devastation. And in the late 90s, the Canadians, who fussed in advance, actually provided the Mil's "medium-heavy" rotorcraft with their engines. When they turned their backs, they had to turn to JSC "UEC-Klimov" again. Be that as it may, the "Klimovtsy" based on the architecture of the base TV7-117 engine have created many power plants, ranging from version C for the Il-114 and Il-114T aircraft and ending with the TV7-117K gas turbine for marine equipment - high-speed catamarans.
Work on the helicopter modification at the Klimov Design Bureau began almost immediately after Pratt & Whitney Canada left the game in 2009, and two years later the power plants were ready for flight tests on the Mi-38. One of the distinctive features of the motor was a digital electronic control and monitoring system of the FADEC BARK-6V type. The main task of this unit is to optimize engine operation, reduce fuel consumption, as well as increase the resource of individual units. The design is based on a compact and efficient centrifugal compressor with five axial stages and one centrifugal. Unfortunately, the high pace of work inevitably affected the perfection of the motor design.
In 2012, the first Mi-38-2 OP-1 helicopters were assembled (Canadian motors were removed from the machines and domestic ones were installed) and OP-2, which were planned to be shown at MAKS-2013, but when combining the motor with the VR-382 gearbox, problems arose. As a result, the unit had to be refined, passed through 300-hour tests, and only after that put it on a helicopter.
The Mi-38 with domestic engines first took off from the ground only on November 13, 2013. Over the next year, the motor was in trial operation, and in May 2015 it successfully passed 150-hour certification tests.
At the moment, a contract has been signed with the Klimovites for the supply of 50 helicopter engines. Interestingly, the 2800-horsepower TV7-117V can potentially be installed on helicopters with a rear power take-off shaft - on the Mi-28 and Ka-50/52. To be precise, the helicopter with domestic engines bears the name Mi-38-2 (sometimes it is also renamed Mi-382), while the copy with Canadian engines is Mi-38-1.
The dust protection device of TV7-117V engines works more efficiently than the classical fungal type devices that we are used to seeing on Mi helicopters. The fact is that cars with "fungi" above the cockpit have restrictions on taxiing in a snow whirlwind in the temperature range from minus 5 to plus 5 degrees. In this range, snow turns to ice and a massive build-up forms, blocking the air supply. The Mi-38 has a dustproof device that is free from this drawback and provides air preparation in any operating mode in the range of the purification degree of 95-98%.
An important advantage of the helicopter is the presence of an auxiliary power unit TA14-038 with a capacity of 30 kW from PJSC NPP Aerosila - the very “heart” without which it would be impossible to start the main engine. This is an important factor in the autonomy of the Russian helicopter, since the start of the motor was electric on cars with Canadian motors. In addition, the additional power plant of the helicopter ensures the operation of air conditioning systems on the ground.
Key Benefits
What else can the newest Russian Mi-38 helicopter boast of? First of all, four world records. True, they were beaten by a car with Canadian motors, but this does not detract from the merits of the designers and testers. Many parameters of the machine during the first flights showed an excess over the calculated ones - for example, the main rotor thrust while hovering was 500 kg more than “on paper”. By the way, the first flights of the Mi-38 in 2003 and further tests in general turned out to be resonant events. Test pilot Vladimir Kutanin received the Order of Courage from the President for his work on the aircraft, and the captain of the aircraft, test pilot Alexander Klimov became the Hero of Russia. During the tests, the helicopter made at least 85 flights, as a result of which a number of changes were made to the OP-2 model: the fuel and hydraulic equipment, the control system and the design of the blades were improved. The world records of the Mi-38 were broken in 2006 and they concerned a record flight altitude of 8170 meters with a mass of 11,100 kilograms and several more achievements in the rate of climb with and without a load. A decent, though not a record, is the maximum speed of the car of 320 km / h, which is close to the limiting parameters for helicopters in the classical sense.
The helicopter builders are also proud of the integrated complex of onboard equipment or IBKO-38 from the St. Petersburg group "Transas". This aircraft provides helicopter flights day and night, as well as in difficult climatic conditions. The cockpit has five 12, 1-inch multifunctional displays TDS-12 to display all the required information with a digital terrain map. The built-in GLONASS / GPS works together with the TNG-1G duplicated helicopter navigation system, the map server and the TTA-12N early warning system. The system provides an instrumental approach according to the second ICAO category, automatic en-route flight, automatic landing approach, missed approach, automatic hovering and flight stabilization in all flight modes. The high level of automation of the Mi-38 made it possible to abandon the third crew member - the flight engineer, and in a critical situation the flight can be continued by one pilot. Interestingly, the Mil OKB does offer as an option the placement of a third crew member for ground handling in case of an autonomous helicopter deployment.
The Mi-38 helicopter would not have been a helicopter of the XXI century without a collimator synthetic vision system on the SVS windshield - this hi-tech provides pilots with a "transparent cockpit" mode. It is argued that the IBKO-38 system is largely unified with the younger model from the Mi-8 (17) and does not require a long adaptation period for pilots. By the way, in parallel with the development of the helicopter, the Transas group was working on a simulator for the novelty. Engineers assure that such a practice of simultaneous work in Russia has been practiced in few places before.
On November 23, 2018, the first flight of the most promising version of the helicopter took place - the transport and landing Mi-38T with a capacity of 40 people with tail number 38015. This machine is intended for the military, and at the moment two copies have been delivered to the military aviation. Among the options, the plant workers offer the re-equipment of the helicopter into a sanitary version and the installation of an additional tank, which increases the flight range to 1600 kilometers.
2019 for the Mi-38 was marked by certification tests in extremely low temperatures. Test pilots performed 57 flights and 18 ground tests of power plants at the Mirny airport and the Nakyn site in Yakutia. After such successful experiments at temperatures below minus 45 degrees, the helicopter left for home in the hold of the Ruslan military transport in order to continue testing on Elbrus. On mountain peaks, the machine has shown successful operation at altitudes up to 3 thousand meters above sea level.
At the moment, the global and domestic market (in Russia it is generally 9% of the market) of medium-heavy helicopters has already reached its saturation point, and sales of the Mi-38 will be significantly lower than the lighter "bestseller" of the Mi-8/17 line. But at the Kazan Helicopter Plant, it is on the novelty of this class, along with the light Ansat, that the main stake is made.
In any case, the competitiveness of the classic Mi-8/17 will come to an end one day, and the Mi-38 must partially replace it. Among foreign analogues, one of the closest competitors is the Airbus Helicopter H225 with a carrying capacity of 5500 kilograms, but its cargo compartment is almost two times smaller than that of the Russian Mi.
In the meantime, the plant is loaded with defense orders for the Mi-38T version, there is news about the first planned foreign deliveries and great hope for contracts with other law enforcement agencies and government agencies. In accordance with the program "Development of the aviation industry for 2013-2025", the sales of the Mi-38 until 2025 are planned at 175 aircraft, and by 2030 - at 264 helicopters. History will show how optimistic these forecasts were.
