An omnivorous aircraft engine for small aircraft has been developed in Russia. Small aviation gas turbine engine Engines for small aircraft
Let's try to understand what we need from an engine for an SLA? What should it be like?
Let's start with the simplest. The motor should not only be affordable for us, it should be as cheap as possible. The ideal option is free. We go to the landfill, pick up abandoned pieces of iron, disassemble, replace, finish, etc., etc. Those who doubt and the most gullible can entrust this to someone else. For example, a reputable company that employs knowledgeable specialists. We are confident that they will do well. We can fully trust the authors of articles related to bringing well-known car engines into flight condition - used ones, of course.
However, such actions are very reminiscent of the story of how to make a gun from a latch. Let's say the answer right away. The only ready-made part for the pistol is the latch, which will become the firing pin. Everything else will need to be made from scratch.
Likewise, a motor from a junkyard has some parts suitable for production. The rest will have to be bought, made, modified. As soon as we grab this piece of cheese, we will find that further events are developing within the confines of the mousetrap. And you will have to pay off with decent money.
Of course, if your needs are limited to airfield circling a few times a year, then a successful engine from disassembly will be a brilliant solution for you. In the end, according to Senka and the hat. You just need to remember your limitations.
Well, if you want something more, like a Kalash rifle, for example, then you’ll have to gild the handle. The only question is - to whom and for what?
From what has been said, the questions mentioned earlier follow. If we pay decent money, we must understand what exactly it is for.
Historically, at first the SLA required an extremely light, unpretentious engine. These were two-stroke motorcycles. Having low power and air cooling, they worked at the limit and quickly failed. Their high speeds forced the use of small-diameter propellers, which could not develop sufficient thrust. The development of SLA took a lot of blood and sweat. I wanted something strong and reliable. The era was the use of motors from snowmobiles. They were used all over the world. We know Buran with its RMZ-640. It had power (up to 30 hp!), but questionable reliability. Overheated. The Rotaxes solved this problem in a non-standard way for aviation - they introduced liquid cooling.
Thus, sufficiently high power was achieved at high speeds, which were reduced by a gearbox, and the cooling problem was reduced by a radiator. Please note - in large aircraft, as a rule, there are neither high speeds nor liquid cooling. And we have them in SLA. The historical path of development of SLA led to this.
However, is this good?
The same Rotax 503 demonstrates to us the greatest reliability of air cooling with a power of 50 hp. With. Maybe we don’t have to have high speeds and it’s enough to have air cooling?
Why are four-stroke engines so interesting these days? Its reliability. This is the main thing we are willing to pay for. Pay in money, heavy weight, complexity of installation and maintenance. Let's realize that at the same time we are leaving the path that was set by the beginning of the development of SLA - we are abandoning a very light and simple engine. We are forced to take a heavy and complex propeller-driven installation based on a four-stroke engine. This is necessary for our well-being. We want to fly freely and not be afraid that our engine will suddenly stop and put us in a very uncomfortable position.
And if so, then we will have to critically evaluate our, so to speak, property.
“Inventory” turns out to be simple and short-lived. We have such engines as Rotax 912, Suzuki, Subaru, Limbach, VW. Everything else is exotic.
The first three are liquid cooled and geared. And the last two are “deprived of fate” - they, alas, do not have them.
"Rotax 912", as a rule, shines with its novelty. Suzukis and Subaru always have a rich, if dark, automotive past - their last location being a junk car or a scrap yard.
"Transporterovsky" (bus) VW is from the same place. But we won't talk about him.
"Limbach" is a new aristocrat, as they say. It's not cheap. Its acquisition must be financially justified. However, the Limbach, after a major overhaul carried out by the manufacturer of the same name, is almost half the price (including significantly cheaper than the Rotax 912) and is no less reliable than a new one.
But the brand new VW finds itself in an invisible position. It is quite inexpensive - no more expensive than well-processed used car engines. It is accessible, reliable, easy to use, and ascetic in nutrition. And most importantly, there are a huge number of them flying around the world, but we know almost nothing about them.
That's what we're talking about.
Before listing the advantages of VW, first about its history.
Since mass production of the famous Volkswagen Beetle began in post-war Germany, its four-cylinder air-cooled boxer engine has attracted the attention of light aircraft designers around the world.
This engine is remarkably similar to the classic Lycoming and Continental four-stroke boxers, and not just in appearance. The Beetle operates in the same, most optimal, speed range. This allows the propeller to be mounted directly on the crankshaft, and also ensures low specific fuel consumption and long service life. The engine is astonishingly simple, as simple as a four-stroke four-cylinder engine can be. Compare it with photographs of sophisticated car engines, and you will understand this without any comment.
Probably, historically, the first example of the use of the Beetle on light aircraft was the Jodel D-9, designed by Jean Delamonte. This single-seat airplane appeared in France immediately after the war; it initially had a 990 cm3 engine with a power of 26 hp. With. Then they installed more powerful ones.
Subsequently, many more famous single-seat aircraft appeared, which used the first production Zhuk engines with a power of up to 34 hp. With. For example: Druine Turbulent, Tipsy Nipper, Headwind, Taylor Monoplane.
Since the late 60s, thanks to motor sports and tuning enthusiasts, Beetle engines with increased displacement have become widespread. A standard crankshaft with a stroke of 69 mm allows you to get a volume of up to 1915 cm3, and with an increased stroke - up to 2700 cm3. The most remarkable thing is that the dry weight of the engine remains almost unchanged.
The 1835 cc should be considered a real workhorse among these engines. On its basis, they began to build two-seater aircraft.
In the 70s, certified aircraft engines based on the Beetle appeared in Europe. They are produced by three companies: Limbach Flugmotoren, Sauer (Germany) and JPX (France).
Over the past 30 years, Limbach Flugmotoren has produced more than 6,000 engines.
They are used on various aircraft with a flight weight of up to 900 kg and have flown for more than 16 million hours! Sauer produces a very limited number of its engines.
Engine JPX 4T60
It was originally developed for the Robin ATL, a two-seat club plane that was mass-produced in France. The total flight time of these engines already exceeds 550 thousand hours.
Well, what is VW? The engine is an aircraft version of the famous VW Beetle automobile engine and is intended for use in ultralight and experimental aircraft. Its predecessor can be considered the Continental A-65 with a power of 65 hp. With. and weighing 80 kg. He stood on such famous aircraft as Piper Cub, Taylorcraft, flying to this day. This engine was produced since 1937 and was discontinued in 1970. And from the 60s until the appearance of the Rotax 912 in America, there was no alternative to the VW engine! It was present on all aircraft where power of less than 100 hp was needed. With. A micro-Lycoming, so to speak. Until now, almost all American amateur aircraft fly on it. That's what they call him there - Beetle. There are also many of them in Australia. Their number is difficult to estimate. VW is increasingly appearing on trikes. Operating experience in aviation exceeds 40 years.
The flying Beetle can be purchased in disassembled form from the American company GPAS. Do it yourself - kit kit!
The painstaking process of selective assembly involves using a drill to equalize the volumes of the cylinder heads, as well as the masses of the pistons and connecting rods. The process involves a series of checks, during which the engine parts are measured, assembled and disassembled several times. Let us especially note that we are talking about a completely new engine, as they say, “zero”.
VW has a long lasting aluminum crankcase. Starter with a power of 1.04 kW. It does not have a distributor, but it has an aircraft magneto Slick 4316. Bosch W8AC automobile spark plugs with adapters for Slick shielded high-voltage wires. Carburetor Zenith 1821. Gasoline 95. Mineral oil, for example from Delphi, costs no more than $2 per liter. The motor weighs no more than 78 kg with all equipment and oil.
The tests were carried out on a S-5 cart with a Maverick-2 wing. The instrument panel was supplemented with devices for monitoring exhaust temperature and suction pressure.
At a maximum rotation speed of 3600 rpm, the engine develops power of more than 65 hp. With. This value depends on the build quality. At a frequency of 3400 rpm and the corresponding power is slightly more than 60 hp. With. The engine can run its entire life without stopping. And he is assigned to live at least 1000 hours until the first possible overhaul. We draw the reader's attention - a resource of 1000 hours or more is not someone's wish list. This resource is confirmed by statistical data from an astronomical number of tests and observations. One of the participants in the American aviation computer forum reported that after flying for one and a half thousand hours, he became doubtful and disassembled his VW. And he didn’t know what to do with him next. Just in case, I changed the rings. And believe me, this is no exception.
In this regard, let us allow ourselves an immodest question, so to speak, for backfilling. What is the basis for claims that a rebuilt used car engine, such as a Suzuki or Subaru, has a service life of 1000 hours? The fact that such a motor can travel 100-150 thousand kilometers before overhaul does not mean that its flight life will be 1000 hours or more. How does a car wheel work and how does a propeller work? The wheel has a gearbox that, at any acceptable speed, returns the engine to its optimal, gentle operating mode. A propeller almost always forces a car engine to operate at speeds not much lower than the maximum. This is how our engine would work in a car without a gearbox. Therefore, 100 thousand km at a speed of 100 km/h for 1000 hours has very little in common with when the same engine starts turning a voracious propeller. What tests and measurements confirm these 1000 hours? For how long and by whom were they carried out? Was the engine really running in only one gear all this time? As we see it, there are more assumptions and faith than proven knowledge. Let us emphasize once again that we are talking about a car engine.
Like the Lycoming, the VW engine is designed to operate the propeller in a gentle manner and is therefore aircraft grade. The service life of such motors has been practically confirmed.
VW flight tests were carried out. A wooden monoblock propeller of the TsAGI SDV-1 series with a diameter of 1.5 m was used. During the flight it was felt that the thrust was quite sufficient. With a flight weight of 340 kg at a speed of 80 km/h, the rate of climb is 4 m/s. The rotation of the propeller is 3300 rpm, power is 62 hp. s., propeller efficiency 0.52. The corresponding design thrust in flight is 108 kg. At the same time, the propeller is somewhat heavy - the motor spins it at a speed of 120 km/h to only 3400 rpm. Nevertheless, the rate of climb at 120 km/h is quite noticeable - 1.5 m/s.
Like any air engine, the VW needs to be cooled. There's nothing complicated about it. Air intakes made of millimeter aluminum are very light.
The engine was also tested in situ operation at 2400 rpm, corresponding to two-pilot cruising (flight weight 420 kg). The air temperature was 5°C. In half an hour of operation, the temperature of the cylinder heads climbed to 210°C, and the oil temperature to 95°C. Due to the lack of an oil cooler. Fuel consumption - 9.2 l/h. Specific gasoline consumption no more than 200 g/hp. h.
During flight, the temperature of the cylinder heads changes in accordance with changes in engine operating mode. At higher speeds it grows slowly, and when the speed decreases it drops quickly. The maximum permissible temperature of the cylinder heads is 250°C. Minimum 100°C. Comfortable for the engine 160-190°C.
Contrary to popular belief, it is easier to cool an air-cooled motor than a liquid-cooled one. In the latter, heat is first transferred from the cylinder wall to the liquid, then from the liquid through the radiator to the air. And this is with a small temperature difference between the hot liquid and not very hot cylinders, between the liquid with a temperature of about 100 ° C and air. Each of the intermediaries has its own thermal resistance. With air cooling, these intermediaries are absent. Heat is immediately transferred from the cylinders to the air. The temperature difference between the cylinder fins and the air is noticeably greater. This fact is also the reason for the high efficiency of air-cooled motors, since they have a higher thermodynamic efficiency.
When flying in cold weather below 5°C, the intake pipe freezes. It is advisable to heat it up like on Limbach. The Zenith 1821 carburetor delivers the fuel-air mixture vertically upward. Therefore, starting a cold engine requires pre-filling the cylinders with fuel, for example, using primers. Or simply disconnect the rubber pipe from the inlet pipe and fill in gasoline with a syringe. Launch is instant.
The only thing you need to remember, especially in the fall, is the spark plug gaps. The calm and uninterrupted operation of the engine lulls the pilot. During long flights, spark plug gaps increase from 0.4-0.5 mm to 0.5-0.6 mm. Cold autumn is coming. According to the instructions, a gap of 0.3-0.4 mm is now required - almost half as much. As a result, during landing at idle speed the engine can exercise its right to stop. And in a random way. The only reason is the candles.
Installing the engine is not particularly difficult. Simple requirements for cooling mode, precautions when supplying fuel, and electrical wiring do not contain anything original. VW's service schedule calls for a series of simple checks every 50 hours. These include changing the oil, checking valve clearances, condition of spark plugs, etc. Replace spark plugs every 150 hours.
When it comes to liquid-cooled engines, the cooling system components require constant attention and significantly increase the amount of maintenance work required. It has long been known in large aviation that the best system is the one that is not on board the aircraft. Especially if its presence does not lead to an increase in performance characteristics. A common distinguishing feature of both modern car engines and Rotaxes is a large number of additional equipment, including those not located on the engine. If it is not installed, the engine will not produce all the horses. This happens, for example, with the 912, which will not produce the declared power either without a specially tuned exhaust or without an intake receiver. As a result, 80 horsepower with a displacement of only 1.2 liters comes at a high price. The power plant gives the impression of a frustratingly complex and heavy device.
The widely held belief that automobile engines are significantly superior to aircraft engines is actually a myth. Porsche tried in the 80s of the last century to create an aircraft engine based on its famous 911. It seems that everything is correct, both the cooling is air and the circuit is opposed. Only here is the gearbox again and 5600 rpm. We received 200 liters. With. with a mass of 214 kg, unclear prospects for service life and no reduction in specific fuel consumption compared to the classics.
Based on materials from magazine publications
The problem of light engines for small aircraft was not written about except in the yellow press. They wrote a year ago, and two years, and ten years ago. General aviation development programs are being adopted; the Central Institute of Aviation Engine Engineering TsIOM im. A.V. Baranova. The government is adopting assistance programs for manufacturers of GA equipment. Domestic aircraft appear in the press and on television. They flicker and disappear. Somewhere they fly, somewhere they are tested.
Only at the field sites and GA airfields, foreign Cessnas, Robinsons and Teknams are still flying. And Russian-designed cars, not counting the Yakov, of course, look more like a curiosity. And, as in previous years, everyone talks and writes about the lack of a domestic light engine. Why not at least do it as they did in the old Soviet times. A huge country did not hesitate to take a foreign engine, adapt it to the capabilities of our production, improve something, lose quality somewhere, but at the end have our domestic engine, which can serve as a model and prototype for a whole line of modernized engines. The domestic history of aviation development is full of similar examples, and there is no point in citing them here.
Where is the cart?
So, in a huge country, there is practically no infrastructure left for the production of low-power piston engines. Those that would be able to lift our small aircraft and put them on what is called “the wing.”
However, there is a way out of this situation. The solution may not be the fastest or simplest, but there is one. This is the development of our own, domestic micro and mini GTE engines (gas turbine engine).
Huge holdings, consortiums and all kinds of federal state unitary enterprises (who doesn’t know this is the Federal State Unitary Enterprise) are studying the problem, developing conceptual projects, creating enterprises with foreign participation and mastering public investments. Probably, after a certain amount of time has passed, we will end up with some kind of finished product as a result of all these corporate efforts.
CIAM conducts R&D
The Federal State Unitary Enterprise "Central Institute of Aviation Engine Engineering named after P.I. Baranov" conducts broad-based research and development on the creation of promising gas turbine and piston engines in the interests of developers of unmanned aerial vehicles, small aircraft and helicopters. AviaPort provides a systematic presentation of the speeches of the head of the CIAM sector (small gas turbine engines) Vladimir Lomazov and the head of the CIAM sector (PD) Alexander Kostyuchenkov at the II international conference "Unmanned Aviation - 2015".
«… Work on promising piston engines
In Russia, there is currently no production of piston aircraft engines for drones and light aircraft and helicopters, which forces domestic designers to use foreign-made aircraft engines. Due to the huge need for such engines, CIAM is conducting R&D and developing projects for promising piston aircraft engines for their use in unmanned aerial vehicles, light aircraft and helicopters.”
«… Basic requirements for aircraft engines
The main criteria when creating advanced engines were the cost of operation, the assigned life between overhauls and fuel efficiency, which together determine the cost per flight hour. Calculations have shown that for engines of this class, the cost of a flight hour should be no more than 500 rubles per flight hour (excluding the cost of fuel and lubricants), the technical resource should be at least 8,000 hours. With such indicators, the life cycle cost will be 3.2 million rubles in today’s prices.”
“...New technologies for creating small-sized gas turbine engines
CIAM is working to introduce the latest technologies to reduce weight and improve the quality of individual components and parts. It has been confirmed that the manufacturing cost of a compressor wheel has decreased by almost 20 times compared to a classic wheel with inserted blades. Due to the use of modern casting technologies, the price of the rotor is reduced by approximately 15-18 times compared to the rotor of a standard auxiliary power unit of the same size found on domestic aircraft. As a prototype, a starter-generator with the ability to spin up to 90 thousand revolutions has been manufactured and will be tested on the stand, which is placed on a shaft without a gearbox and significantly reduces the weight of the engine. It provides power up to 4 kW and weighs only 700 grams, compared to today’s 10 kg.”
(based on portal materialsairport http://www.aviaport.ru/news/2015/05/08/338921.html
Laboratory of Intellectual Mechanics "Audit Analyst" (AA+)
Behind this intriguing name lies a group of enthusiasts who have developed, created, and are currently testing the first prototype of a micro gas turbine engine.
Sergey Zhuravlev General Director, inspirer and generator of ideas of the Laboratory with his brainchild in his hands.
This is what Sergey Zhuravlev, General Director of the Laboratory of Intellectual Mechanics "Audit Analyst" (AA+), says about his team:
"Who are we?
A team of developers of models and prototypes of complex systems (ecosystems), and algorithms for managing them, both in the technical and humanitarian fields.
Our competencies are based on our own concept of organizing a research and development community, distributed (networked) production and the continuous process of improving the line of high-tech products in the testing and installation complex. We do not consider it necessary to buy machines and build a factory. Russia already has so much excess production capacity and purchases of the latest equipment that they need to be loaded with work.”
Sergei is full of optimism and healthy realism, and he has every reason for this.
“We had a rare chance to enter the global elite of small turbine manufacturers. Minimization and localization, robotization and autonomy - trendsXXIcenturies, in which it is still possible to integrate on an equal footing with the leaders in the energy supply of small aircraft, unmanned aircraft, and local energy. Russia has very strong schools of physics, mathematics, materials science and engineering. Their potential allows, in a minimum turbine volume, to achieve maximum efficiency values, primarily operational, with little effort and resources.”
A prototype of a low-thrust gas turbine engine of the MkA series
It should be noted that the development of low-thrust gas turbine units is only one of the areas that the AA+ Laboratory is engaged in, and this project is completely private, and perhaps that is why, after all the calculations, studies and tests, they end up with a ready-made prototype.
So casually, on the windowsill, on a notebook with calculations and diagrams, the first experimental MkA low-thrust gas turbine engine fit. The founder of a series of engines of different power that can be used in various industries.
The engine is already being tested on a bench in the laboratory. Here are some of its parameters that are already clearly defined:
Basic data of the prototype low-thrust gas turbine engine of the MkA series (micro aviation):
Weight – 2060 gr.
Length – 324.00 mm
Main diameter – 115.00 mm
Width with pylons – 128.00 mm
Performance characteristics:
Maximum thrust – 200N
Working thrust – 160N
Fuel consumption (at maximum thrust) – 460.00ml\ min
Fuel used – kerosene\diesel fuel
Maximum rotation speed – 120,000 rpm
“The developed engine differs from the analogs studied by our design bureau in design, materials, and characteristics. And also by pre-thought-out integration into a range of products.”
Dmitry Rybakov
Deputy Director for Innovation at the Unmanned Systems Group of Companies
The Unmanned Systems Group of Companies is so confident in the prospects of the series of engines developed by the Laboratory that they have begun designing a promising UAV specifically for them.
I am absolutely sure that after some time we will see light, powerful and economical engines from the AA+ Laboratory not only on light aircraft, gyroplanes and helicopters, but also on large aircraft.
In conclusion, I would like to quote one more statement from Sergei Zhuravlev.
| Vitaly Selivanov, Honored Test Pilot of the Russian Federation |
A steam locomotive cannot be more beautiful than its boiler,” this is what steam locomotive engineers said at the beginning of the century. At the dawn of aviation, due to the lack of a light engine, people began to fly gliders from the mountains using flow streams. Only the creation of a lightweight gasoline-powered internal combustion engine finally gave rise to heavier-than-air vehicles. A gasoline engine (with a reserve of fuel) was ten times lighter than an electric engine of the same power with a battery or a steam engine with water and fuel. The Wright brothers, the French, the Germans, and after them in Russia, by the way, only in the summer of 1910, a hundred years ago, three devices took off: A.S. Kudasheva, Ya.M. Gakkel and I.I. Sikorsky. True, all devices had imported Anzani gasoline engines of 25 and 35 hp. |
It would be a sin not to remember our great ancestors, but, unfortunately, we still have almost the same problems with engines for small aircraft. We inherited from the USSR only one serial piston engine, the M-14. The engine is simple, reliable, unpretentious to fuel and oil. Not afraid of frost. Relatively inexpensive if you don’t fly it very much. This is why they love the M-14 engine.
What do they fly now, in “small aviation”, i.e. ultralight and lightweight aircraft? The most common, well-known and almost everywhere in the world engines are serviced by the Austrian company Rotax 912 and 914. With a power of 80–100 hp. , they are installed on vehicles with a take-off weight of up to half a ton, with a crew of up to two people. These are educational, tourist, amateur devices.
As soon as you need to perform complex aerobatic maneuvers together (with an instructor), you will need a more durable and heavier aircraft with a take-off weight of 800–1000 kg (for example, Po-2, Yak-18, Yak-52). Moreover, with an engine of 100–160 hp. half of the flight time will have to be spent regaining the altitude lost during aerobatics at a vertical speed of 2–3 m/sec. And if you want to gain altitude quickly, then the M14 engine is suitable. On it you can gain up to 10 m/sec, and the loss of altitude during aerobatics will be much less. The M14's competitors are the American Lycoming and Teledyne Continental, the Czech Walter, and the German Centurion. Lycoming and Teledyne Continental are capricious when launching on the ground even in summer, they are either hot or cold, and in winter they cannot be launched in the air at all. They use only their own, expensive, imported gasoline and lubricant, but all their disadvantages are outweighed by two advantages:
1. They work at “maximum” without time limits.
2. Fuel consumption is 2 times less than that of our M14.
If we combine the main technical and economic indicators of engines into one table with the task of obtaining the cost of operating an engine with aircraft flight time until the resource is fully used - 10 thousand flight hours - we get a table.
It shows that for 10,000 flight hours on our M-14 you will have to pay 30% more than on the Alison theater and almost three times more than on the Centurion diesel. But the M601 engine, although it costs almost three times more than the M-14, each of its horsepower costs the operator three times less than the M-14. Therefore, if we want to get an aircraft for basic training at a military flight school, where we are forced to work intensively and provide a very long flying time, then, of course, the aircraft must be equipped with a theater engine, and for now there is no better production engine in sight than the M601!
The aircraft needed, of course, is aerobatic, with an operational G-force of up to 7, at a sufficiently high altitude (7–10 km), and therefore with a pressurized cabin. The most suitable engine available and serviced in Russia for the planned aircraft is the Czech Walter M601. Its analogues, Pratt&Whittney, are newer and more economical, but there is no system for their maintenance and operating experience in Russia. It is too early to install a diesel engine on an aerobatic aircraft with a flight time of 0.5–1.5 hours - it is difficult (on the Internet, tankers have a very useful comparative analysis of the advantages and disadvantages of gas turbine and diesel engines).
So far it turns out that the cheapest flight training is on a glider when launching from a winch. For 3 euros (120) rubles, you will be thrown on a glider to a height of 500 m, from where you will calmly descend for about 8-10 minutes or you can go free soaring. The gliders are followed by ultralights with a take-off weight of up to 500 kg and Rotax 912 and 914 engines with a power of 80–100 hp. They can be used to teach circling flights, simple aerobatics, and route flights. This will give you 30–40 hours of flight time and reach the level of an amateur pilot. Private flight schools or DOSAAF can provide such training. Information: ultra-light aircraft are already being designed, which will use electric motors with a battery for up to 30 minutes of flight. And cheap, and environmentally friendly, low noise and safe.
Next stage: aerobatic training piston aircraft. One of the preferred options could be the Yakovlev Cadet aircraft. It can be used to teach complex and aerobatics, formation flights and at night. But getting the military to switch back to a piston aircraft will be very difficult, the flights are physically difficult, and the pay and benefits will be reduced. Therefore, such machines will most likely be useful to DOSAAF and private flight schools. The engine will still have to be changed - it is too expensive to operate - 30% more expensive than the twice as powerful M601 turboprop engine.
If the unit cost of a flight hour is taken to be the cost of a flight on a high-tech aircraft with a high-speed theater with a maximum speed of about 500 km/h, then, depending on the maximum speed of the aircraft, you can get the price ratio for a flight hour on different aircraft.
The graph clearly shows that up to a maximum speed of 500 km/h, the price of the aircraft increases smoothly linearly, from a speed of 500 to 800 km/h it grows parabolically and then goes up almost linearly. Hence the conclusion: there is no point in increasing the maximum speed of a aircraft with a theater of operation of more than 500–600 km/h, since a small increase in speed is too expensive both in the price of the aircraft and in operation. Apparently, for these reasons, the customers of the Pilatus RS-7MK aircraft from South Africa reduced the engine power.
If the theater-mounted aircraft has an approach speed of less than 150 km/h, then the need for a piston-powered aircraft for initial training for a military school may disappear, and this problem can be solved on the theater-powered aircraft at a lower cost.
For basic training at a flight school, of course, as throughout the world, there is an urgent need for training equipment with a theater of operations (“Aviapanorama” Nos. 1 and 2, 2010).
We see how the aviation industry of China, India, Brazil and other developing countries is supported with the help of the state. Even Türkiye plans to release its own theater-mounted vehicle in 2011. Our large business - mostly technically illiterate - buys primarily real estate and luxury goods. By the way, even before the revolution, our financiers did not donate much to technical progress. After all, it was not here, but in the West that large prizes were awarded for flights across the English Channel and for other record flights.
With the lifting of the restrictive airspace system promised in 2008, a large Russian market for small private jets is now likely to open up at the end of 2010. The state could use this situation to develop its own production of light aircraft. You can, like China and India, buy batches of the best foreign aircraft, with the right to subsequently produce them. But much more important for us, the aviation industry and aviation enthusiasts, is the purchase and licensed production of the best, most common and reliable Rotax, Teledyne Continental, Pratt&Whittney engines with a power scale not produced in Russia to this day. With a wide range of engine choices, our aviation industry could provide the Russian market with the aircraft it needs. Historical examples only confirm this. This was the case with the Li-2, and so it was with the purchase of the English Nin-1 and Derwent-V jet engines; as a result, they received the world’s most popular fighter, the MiG-15, and an almost equally massive front-line bomber, the Il-28.
What I would like to pay special attention to. Our national habit of poverty has given rise to a massive tendency: we’ll do what we can, and then we’ll finish it in a series. You need to remember what students of aviation universities are taught: finalizing a sketch will cost the price of an eraser and a pencil (kopecks), a model will cost the price of the lumber spent (thousands of rubles), a prototype aircraft will cost millions of rubles, and modifications to a production aircraft will require a lot of money, which can lead to the crash of the entire program altogether. To avoid such mistakes, we need to love the customer and do everything in a timely manner so that our product is better than that of our competitors.
3rd September 2010 16:14. Category , Views: 1372Operation of a radial piston engine.
Hello friends!
Today we are starting a series of articles about specific types of aircraft engines. The first engine that will receive our attention is . He has every right to be the first, because he is the same age as modern aviation. One of the first planes to fly was the Wright brothers' Flyer 1 (I think you've read about it :-)). And it had a proprietary piston engine running on gasoline.
For a long time, this type of engine remained the only one, and only in the 40s of the 20th century did the introduction of an engine with a completely different principle of operation begin. It was a turbojet engine. Read why this happened. However, the piston engine, although it lost its position, did not leave the scene, and now, due to the fairly intensive development of the so-called small aviation (or general aviation), it has simply received a rebirth. What is it like? aviation piston engine?
Operation of an internal combustion engine (the same in-line piston engine).
As always :-)… In principle, nothing complicated (turbojet engine is much more complicated :-)). In fact, it is an ordinary internal combustion engine (ICE), the same as on our cars. For those who have forgotten what an internal combustion engine is, let me remind you in a few words. This is, simply put, a hollow cylinder into which a solid cylinder, smaller in height, is inserted (this is the piston). A mixture of fuel (usually gasoline) and air is supplied into the space above the piston at the right moment. This mixture is ignited by a spark (from a special electric candle) and burns. I will add that ignition can occur without a spark, as a result of compression. This is how everyone knows it works diesel engine. As a result of combustion, gases of high pressure and temperature are produced, which put pressure on the piston and force it to move. This very movement is the essence of the whole issue. Then it is transmitted through special mechanisms to the place we need. If it is a car, then on its wheels, and if it is an airplane, then on its propeller. There may be several such cylinders, or rather even many :-). From 4 to 24. This number of cylinders provides sufficient power and stability of the engine.
Another diagram of the operation of one row of cylinders.
Of course, an aircraft piston engine is only fundamentally similar to a conventional internal combustion engine. In fact, there are certainly aviation specifics here. made of more advanced and high-quality materials, more reliable. With the same weight, it is much more powerful than a car. Usually it can work in an inverted position, because for an airplane (especially a fighter or sports aircraft) aerobatics is a common thing, but a car, of course, does not need this.
Engine M-17, piston, in-line, V-shaped. Installed on TB-3 aircraft (late 30s of the 20th century)
M-17 engine on the wing of a TB-3.
Piston engines can vary in both the number of cylinders and their arrangement. There are in-line engines (cylinders in a row) and radial (star-shaped). In-line engines can be single-row, double-row, V-shaped, etc. In star-shaped cylinders, the cylinders are arranged in a circle (in the shape of a star) and there are usually from five to nine of them (in a row). These engines, by the way, can also be multi-row, when the cylinders are placed in blocks one after another. In-line engines are usually liquid-cooled (like in a car :-), they look more like cars), and radial engines are air-cooled. They are blown by an incoming air flow and the cylinders, as a rule, have fins for better heat removal.
Engine ASH-82, radial, two-row. Installed on LA-5, PE-2 aircraft.
LA-5 aircraft with ASh-82 engine.
Aviation piston engines often have such a feature as height. That is, with increasing altitude, when air density and pressure drop, they can operate without loss of power. The fuel-air mixture can be supplied in two ways. There is a complete analogy with a car. Either the mixture is prepared in a special unit called a carburetor and then supplied to the cylinders (carburetor engines), or the fuel is directly injected into each cylinder in accordance with the amount of air entering the same. On cars of this type, engines are often called “injection”.
Modern piston radial engine ROTEC R2800.
More powerful R3600 (more cylinders).
Unlike a conventional automobile internal combustion engine, an aircraft piston engine does not require bulky (and, naturally, heavy :-)) transmission mechanisms from pistons to wheels. All these axles, bridges, gears. For an airplane, weight is very important. Here, the movement from the piston is transmitted directly through the connecting rod to the main crankshaft, and on it already stands the second important part of an aircraft with a piston engine - the propeller. A screw is, so to speak, an independent (and very important) unit. In our case, it is the “propeller” of the aircraft, and the quality of the flight depends on its correct operation. The propeller is not a part of the engine, but they work in close cooperation :-). The propeller is always selected or designed and calculated for a specific engine, or they are created simultaneously, so to speak as a set :-).
Radial engine M-14P. Installed on sports SU-26, YAK-55.
SU-26 with M-14P engine.
The principle of operation of a screw is a rather serious (and no less interesting :-)) issue, so I decided to highlight it in, but now let’s return to the hardware.
I already said that now piston aircraft engine“gaining momentum” again. True, the composition of aviation using these engines is now different. The composition of the engines used has changed accordingly. Heavy and bulky in-line engines are practically a thing of the past. A modern piston engine (most often) is radial with 7-9 cylinders, with good fuel automatics and electronic control. One of the typical representatives of this class, for example, the ROTEC 2800 engine for light aircraft, was created and produced in Australia (by the way, by immigrants from Russia :-)). However, in-line engines are also not forgotten. This is, for example, ROTAX-912. The domestically produced M-14P engine, which is installed on the Yak-55 and SU-26, is also well known.
Engine Rotax-912, in-line. Installed on Sports-Star Max light sport aircraft
Sports aircraft Sport-Star Max with Rotax-912 engine.
There has been a practice of using diesel engines (as a type of piston engines) in aviation since the war. However, this engine is not yet widely used due to existing problems in development, in particular in the field of reliability. But work is still underway, especially in light of the impending shortage of petroleum products.
In general, it’s still too early to write it off :-). After all, as you know, the new is the well-forgotten old... Time will tell...
On September 3, the first launch of the MS-500V-02S turboprop engine for promising small aircraft took place. This is the first engine designed by our designers using the so-called “reverse” design. Anatoly Mikhailyutenko, deputy chief designer of the UGK, head of this development, talks about it in more detail.
This engine is designed to work with German MT-Propeller propellers. We conceived it a long time ago, and the first prototype was assembled and demonstrated at the International General Aviation Exhibition AERO-2014 (Germany, Friedrichshafen). When representatives of the Chinese company saw it, they expressed a desire to use this engine for their training aircraft. In February 2017, we agreed with them on the technical specifications for the engine, within six months we developed design documentation and then within a year we manufactured a stand, parts and assembly units and assembled the first copy of the MS-500V-02S engine. And on September 3, the first launch of this engine took place.
Anatoly Vasilyevich, please tell us how it all happened?
When the necessary preparatory work was completed, we, according to tradition, invited the President of MOTOR SICH JSC V. Boguslaev, Technical Director P. Zhemanyuk and Deputy Technical Directors for Aviation to launch the new engine. This is a big event for the whole team - this doesn’t happen often for us. We invited Vyacheslav Aleksandrovich to personally press the button and start the new engine. The engine is currently being tested.
What is included in the testing program?
This includes testing the startup, engine and control systems, taking characteristics, etc. The management of the enterprise sets us a task: to obtain a certificate for this engine in August 2020. We carry out some of the work using the groundwork obtained during the development and certification of the MS-500V, MS-500V-01 engines. In particular, these engines have a completely identical gas generator.
What are the technical characteristics of the new engine?
Its power is 950 hp. (takeoff mode). This is the first reverse circuit motor created at our enterprise. The design is similar to the PT6 family of turboprop engines developed by Pratt & Whitney Canada, one of the most popular in the world. But in our traditional aircraft engine market, this segment is not occupied by anyone. American and Canadian manufacturers are in no hurry to sell their engine to China and developing countries, and its price is too high. In addition, their service is very expensive. Together with the State Enterprise “Ivchenko-Progress” we have already brought to the market the family of AI-450 engines, which have occupied their niche, and now we have offered our more powerful version of the MS-500V-02S aircraft engine with a reverse circuit.
What is the advantage of such a design?
It has a number of design advantages, especially for single-engine aircraft. The engine output system is located next to the propeller, which made it possible to reduce the engine compartment of the aircraft and locate the pilot's cabin in close proximity to the engine (no additional space is required to remove hot exhaust gases). The result is a compact aircraft. In addition, the engine has a modular design, which allows for modular repairs in operation. You can disassemble and reassemble the engine without using complex shaped tools and equipment.
Besides training aircraft, where else can MS-500V-02S engines be used?
Aircraft of this class are very popular abroad among farmers, people with average incomes and small businesses. I repeat once again: aircraft with this engine design are the most popular. In our country, unfortunately, this market is not developed due to the low incomes of consumers. And in China, such aviation equipment is in demand, but first of all, our engine is the best option for primary pilot training aircraft. Currently, aircraft for it are being created by the Chinese companies AVIC HONGDU CORPORATION and AVIC GUIZHOU AIRCRAFTCORPORATION.
Anatoly Vasilyevich, please tell us how the work team managed to create a new engine?
A tremendous amount of work has been done. The development of design documentation itself is very hard work. No less important tasks were solved by the technological service and production management. We used mathematical models for particularly complex body parts (drive boxes, gearboxes, etc.), this made it possible to somewhat simplify them and speed up production and eliminate errors arising from the human factor. Prompt clarification, any changes related to the issues of metallurgists, foundries and mechanical shops, saved time. Technologists, designers, production workers and metallurgists worked harmoniously, and everything was done in the shortest possible time. We have not yet created engines at this pace. And as a result we got a working machine. It also helped that the engine had good unification with the MS-500V - we used the main components of this product. This will further make it possible to reduce the duration of finishing the MS-500V-02S and performing certification work.
On all critical moments, we regularly held operational meetings and found optimal ways and solutions to issues when creating the engine. After all, its design contains unique details that we have not made before, in particular, the output system is unusual and complex in design and manufacture. And given the purpose of the engine (a training aircraft that must perform aerobatic maneuvers), it was equipped with an inverted flight function - this is an innovation in our developments.
