Russian vertical takeoff fighter. The Ministry of Defense discusses the creation of a new aircraft with vertical takeoff and landing - peacebuilding - LJ

Recently, Deputy Defense Minister Yuri Borisov said that a new type of aircraft could be created for Russian aircraft carriers: a short takeoff and landing or a full-fledged vertical takeoff. On the one hand, there is no need to invent anything special: the corresponding machine - the Yak-141 - was created back in last years The USSR has proven itself well. But how much does the Russian fleet need such an aircraft now?

Aircraft Yak-141. Photo: WikiMedia Commons

A plane that can take off and land without a takeoff run has long been a dream of aviators: it does not require long runways, but a small area, like for a helicopter, is quite enough. This is especially important for military aviation, because airfields in a combat situation are often destroyed by enemy attacks. For naval aviation, having long runways is all the more problematic, since their size is limited by the length of the ship's deck.

Meanwhile, the rearmament of the Russian armed forces also provides for the construction of new aircraft-carrying cruisers. In this connection, the military began to think: should such ships be equipped with vertical take-off and landing aircraft?

It is worth noting that the Russian defense industry will not have to reinvent the wheel: it has accumulated tremendous experience in this direction. Suffice it to say that the famous passenger aircraft An-28 needed only 40 meters of runway to take off!

VTOL combat vehicles in service with the Air Force Soviet Union there were also, for example, the Yak-38 attack aircraft; however, in the conditions of tropical seas during long-distance cruises of Soviet ships, its engines began to act up. However, a more modern development of Yakovlev Design Bureau - the Yak-141 aircraft, intensive testing of which began in the late 80s, set as many as 12 world records for machines of its class! Alas, this unique aircraft did not survive the collapse of the USSR, and the program was carefully curtailed. However, not completely: in the mid-90s, as part of a contract, the American company Lockheed successfully applied the developments of the Yakovlevites to create the fifth-generation F-35 fighter-bomber, among many features of which (like invisibility technology for radars) was the possibility of vertical takeoff .

But foreign technology without its authors did not bring the Americans success comparable to the Yak-141: the vaunted super fighter, as part of a test arranged in the United States itself, lost a training battle to an almost antediluvian (originally from the 70s of the XX century) F-16. True, the new Phantom nevertheless set at least one "record": for the high cost of its development program, which has already exceeded one and a half trillion dollars. So even President Trump, known for his respect for the rearmament of the army, wondered if the game was worth the candle. And the governments of Germany and France prudently chose not to buy an expensive overseas toy, getting by with their own reliable and proven fourth-generation machines, albeit without the possibility of vertical take-off. It seems that, first of all, because the last function in most cases is not so critical.

Can the enemy bomb airfields? So even the Soviet divisional commander Pokryshkin, during the fighting in Germany, used a solid German autobahn as a runway for his air division. Besides, modern technology allows you to lay (and even more so repair) such roads in a matter of hours.

Aircraft carrier deck too short? But after all, these ships came into widespread use even before the Second World War, when there were no vertical take-off aircraft at all. Other tricks were used to take off and land conventional fighters and bombers.

Now vertical machines make up a rather small proportion of the existing fleet of aircraft-carrying cruisers. Including the Americans, where there seems to be no shortage of "verticals". And all because the "miracle machines" themselves have shortcomings (and very significant ones).

Chief among them: the need to significantly reduce takeoff weight so that the aircraft can take off vertically from the deck. In this connection, for example, the only truly mass-used model, the British Sea Harrier fighter, had a pathetic flight radius of 135 kilometers. However, its speed, only slightly exceeding the speed of sound, was also not impressive.

Both the historic Yak-141 and the state-of-the-art F-35 can reach a maximum speed of just under two thousand kilometers per hour, while the usual carrier-based fighter of the Russian Navy Su-33 can reach 2300 kilometers. In addition, the radius of action of the latter is several times greater than that of its fellow "vertical workers".

Finally, VTOL aircraft are much more difficult to fly precisely because of the change in flight modes. Suffice it to say that one of the two prototypes of the Yak-141 crashed during testing precisely for this reason, despite the fact that an experienced test pilot, and not an ordinary pilot, was at the helm.

The uncertainty in the words of the Deputy Minister of Defense "we are discussing the creation of an aircraft with short takeoff and landing, possibly vertical takeoff and landing" is quite understandable. On the one hand, the revival of the unique developments of the Yakovlevsky Design Bureau will not be a particular problem, except, of course, for the amount necessary for this. It is clear, after all, that it will be difficult to allocate additional billions of dollars for the Russian military budget. But more importantly, will the potential benefits of the effort be worth it? This has yet to be considered by the competent authorities.

Despite the wave of criticism of the vertical take-off concept used in the aircraft, the need to resume the production of aircraft of this class in recent times increasingly spoken in Russia 15 December 2017, 11:33

One of the most expensive "toys" of the Pentagon - the F-35B fighter-bomber - this week took part in a joint US-Japanese exercise aimed at cooling the DPRK's nuclear missile fervor. Despite the wave of criticism of the concept of vertical takeoff used in the aircraft, the need to resume production of aircraft of this class has recently been increasingly discussed in Russia. In particular, Deputy Defense Minister Yury Borisov recently announced plans to build aircraft with vertical takeoff and landing (VTOL). About why Russia needs such an aircraft and whether the aviation industry has enough strength to create it.

The Yak-38, which was put into service in August 1977, became the most massive domestic combat aircraft with vertical takeoff and landing. The car has earned an ambiguous reputation among aviators - out of 231 aircraft built, 49 crashed in accidents and aviation incidents.

The main operator of the aircraft was the Navy - the Yak-38 was based on the project 1143 aircraft carriers "Kyiv", "Minsk", "Novorossiysk" and "Baku". As veterans of carrier-based aviation recall, the high accident rate forced the command to drastically reduce the number of training flights, and the flight time of the Yak-38 pilots was a symbolic figure for those times - no more than 40 hours a year. As a result, there was not a single first-class pilot in the regiments of naval aviation, only a few had a second-class flight qualification.

Combat performance was also dubious - due to the lack of an onboard radar station, he could only conditionally conduct air battles. The use of the Yak-38 as a pure attack aircraft looked inefficient, since the combat radius during vertical takeoff was only 195 kilometers, and even less in hot climates.

Yak-141 supersonic VTOL fighter-interceptor

The more advanced Yak-141 was supposed to replace the "difficult child", but after the collapse of the USSR, interest in it disappeared. As you can see, the domestic experience in the creation and operation of VTOL aircraft cannot be called successful. Why did the topic of vertical takeoff and landing aircraft become relevant again?

Naval character

"Such a machine is vital not only Navy, but also to the Air Force, - a military expert, captain of the first rank Konstantin Sivkov told RIA Novosti. - The main problem of modern aviation is that jet fighter you need a good runway, and there are very few such airfields, it is quite easy to destroy them with a first strike. Airplanes of vertical take-off during the threatened period can be dispersed even over forest clearings. Such a system for the use of combat aircraft will have exceptional combat stability."

However, not everyone sees the expediency of using VTOL aircraft in the land version as justified. One of the main problems is that during vertical takeoff the aircraft consumes a lot of fuel, which severely limits its combat radius. Russia, on the other hand, is a large country, so fighter aviation must have "long arms" to achieve air supremacy.

"The performance of combat missions of fighter aviation in the conditions of a partially destroyed airfield infrastructure can be ensured by a shortened take-off of conventional aircraft from a strip section less than 500 meters long," he said. Executive Director agency "Aviaport" Oleg Panteleev. - Another question is that Russia has plans to build an aircraft carrier fleet, here the use of vertically taking off aircraft will be the most rational. It may not necessarily be aircraft carriers, it may be aircraft carrier cruisers with the lowest cost parameters.

Fighter F-35

By the way, the F-35B today is a purely naval aircraft, its main customer is the US Marine Corps (the aircraft will be based on landing ships). British F-35Bs will form the basis of the air wing of the newest aircraft carrier Queen Elizabeth, which was recently commissioned.

At the same time, according to Konstantin Sivkov, in order to start work on creating a Russian analogue of the F-35B, Russian design bureaus do not have to wait for new aircraft carriers. "VTOL aircraft can be based not only on aircraft carriers. For example, a tanker is equipped with a ramp and becomes a kind of aircraft carrier, in Soviet time we had such projects. In addition, VTOL aircraft can be used from warships capable of receiving helicopters, for example from frigates," our interlocutor said.

We can if we want

Meanwhile, it is obvious that the creation of a Russian vertically taking off aircraft will require impressive resources and funds. According to various estimates, the cost of developing the F-35B and its horizontal takeoff counterparts has already reached $1.3 billion, and several states participated in the creation of the machine at once.

In the modern world, there are more and more aircraft with any characteristics and power. Engineers everywhere are trying to solve the main problems associated with this mode of transport: reduce fuel consumption, increase range, simplify takeoff and landing, but without sacrificing space and cabin space.

Perhaps everyone is used to seeing the acceleration of an aircraft along the runway - this is a difficult task, and the pilots themselves say that the success of the flight as a whole largely depends on takeoff and landing. But isn't it more logical to imagine how this procedure will be simplified if the plane simply rises vertically? However, in a broad discussion, such options are not particularly visible anywhere. Is a VTOL aircraft a myth, a reality, or maybe far-reaching plans behind which the future of aviation stands? It's worth looking into it in more detail.

STOVL F-35B short takeoff and vertical landing fighter

First of all, you need to know that a vertical takeoff and landing aircraft really exists. The first models began to appear simultaneously with the development of jet aircraft, and since then they still haunt engineers around the world. In time, this coincides with the second half of the last century. Their name was very descriptive - turbofly". Since then there was a boom in military developments in technology, the demand was put forward for engineers to develop such an apparatus that would rise air with minimal effort or even from a vertical position. Such aircraft do not require a runway, which means that they can start from anywhere and in any conditions, even from the mast of the ship.

All these projects coincided with others, no less important, related to the exploration of outer space. The common symbiosis allowed us to double our strength, to draw ideas from space design. As a result, the first vertical apparatus saw the light in 1955. We can say that it was one of the strangest buildings in the history of technology. The plane did not have wings, a tail - only an engine (turbojet), a flask-shaped cabin, fuel baths. The engine was made at the bottom. We can highlight the following features of the first turbolet:

1. Rise due to the jet stream from the engine.
2. Management by means of gas rudders.
3. The weight of the first device is a little more than 2000 kilograms.
4. Thrust - 2800 kilograms.

Since such an aircraft could not be called either stable or controllable, the first tests were fraught with great risk to life. Despite this, a demonstration of the device took place in Tushino, and it was successful. All this provided a basis for further research in this area, although the aircraft itself was far from ideal. But the information served to create a new project. It was the first Russian VTOL aircraft called the Yak-38.

The history of the creation of vertical aircraft in Russia and other countries

Many engineers and designers still claim that turbojet engines, which began to be actively used and improved in the 50s, made it possible to make many discoveries that are still used today. One of them is active testing of vertical vehicles. A special contribution was made by the development of this area, or rather, reactive devices, in countries that were considered advanced at that time. Since jet aircraft had huge landing and takeoff speeds, they used very long, large-scale and high-quality runways, respectively. And these are additional expenses, the equipment of new airfields, inconvenience in wartime. A vertical plane can solve all these problems.

It was in the 50s that various samples were created. But they were designed in one or two versions, no more, because all the same, it was not possible to create completely suitable options. After all, rising into the air, they suffered a crash. Despite the failures, the NATO commission in the 60s gave this direction priority as extremely promising. There were attempts to create competitions, but each country focused on its own developments. So, such devices from all over the world saw the light:

• "Mirage" III V;
• Germany VJ-101C;
• XFV-12A.

In the USSR, the Yak-36 became such a turbofly, and after that 38. Its development began in the same years, and a special pavilion was created for testing. After 6 years, the first flight took place. That is, the plane took off vertically, assumed a horizontal position, and then landed vertically. Since the tests were successful, they created the 38th model, and after that Russia introduced the Yak-141 and 201 vertical take-off aircraft in the nineties.

Mirage III V

Aircraft Germany VJ-101C

Aircraft XFV-12A

Design features

The fuselage in such devices can be located vertically or horizontally. But in both cases, there are reactive models and with propellers. Quite powerful aircraft with a vertical fuselage, which use thrust from a sustainer engine. Another option is ring wings, which also give good results during lift and flight.

If we talk more about the horizontal fuselage, then rotary wings are often made here. Another variation is when the screws are placed at the end of the wings. There may also be a rotary engine. In England, they also actively worked on similar devices. There they actively developed a project called innovative, implemented using two engines with a thrust of 1800 kilograms. In the end, even this did not save the plane from an accident.

Now all over the world, work is underway to develop not a military, but a civil vertical aircraft. In theory, these are excellent prospects, because then aircraft will be able to easily fly even to small cities where there are no large-scale and expensive aircraft, and takeoff and landing are much easier. But in fact, there are many disadvantages of such a technology and ideas.

Why vertical planes have not yet found wide application?

Unfortunately, all developments, even if they had good results, cannot boast of reliability. The propeller blades, which help to make vertical takeoff, are striking in their size. Together with powerful engines, they create unimaginable noise. Also, from the point of view of design, it is necessary to avoid any possible obstacles in their path, to exclude the ingress of various objects.

Whatever one may say, it is impossible to cancel the speed limit. Just according to the laws of physics, such an aircraft will not be able to move as fast as modern ones. And if military vehicles can develop a fantastic speed of 1000 kilometers per hour in their case, then with an increase in mass and size for civil aviation, the figure drops to 700 kilometers per hour and below.

In contact with

In the entire history of aviation, only a few aircraft have been created that can do without runways and literally “hover” in the air. Most of these machines were experimental: it was too expensive to "buy" such an unusual property. Only Britain managed, not without the help of the United States, to create a good vertical takeoff and landing aircraft "Harrier". In the USSR, there was also a similar fighter - it was the Yak-38, but it was not suitable for real combat operations. Much more promising could be the supersonic carrier-based multi-purpose Yak 141. It was already being tested, mass production was being prepared, however, the collapse of the USSR did not allow this project to be brought to its logical conclusion.

The history of the development of the vertical takeoff aircraft Yak-141

In 1970, the construction of the first Soviet aircraft carrier "Kyiv" began in the city of Nikolaev. In 1975, it was handed over to the customer, and then three more ships of the same project were launched - Minsk, Novorossiysk and Baku. Initially, it was assumed that all of them would be armed with Yak-38 carrier-based attack aircraft. This plane took off and landed vertically, which at one time made a strong impression on the military leadership of the USSR.

From the very beginning, it was clear that the combat capabilities of the Soviet carrier-based attack aircraft were very limited. The subsonic Yak with vertical takeoff could not lift more than one ton of payload, did not have an airborne radar station, was not capable of vigorous maneuvering, as it had an extremely small combat radius - 195 kilometers (and in practice it is still half as much).

In KB A.S. Yakovlev, work was underway to improve the Yak-38, however, back in 1973, the designers began to think over a newer solution, involving the creation of a completely new machine. It was supposed to achieve a radical improvement in the basic characteristics of the aircraft thanks to a special engine. Its main innovation was to be the ability to work on the afterburner not only during normal horizontal flight, but also during takeoff in vertical mode.

As calculations showed, a power of 15,000 kgf is quite enough to lift a carrier-based aircraft into the air, but even at an early stage of work, it was decided to use power plant, consisting of several engines, because otherwise it would not be possible to achieve balance during vertical takeoff and landing.

In 1977, the government of the USSR officially commissioned the Yakovlev Design Bureau to create a new carrier-based fighter that could also be operated by the conventional Air Force. The designers of the aircraft engine scientific and technical complex "Soyuz" should have taken up the development of the main (lifting and marching) engine. Two years before, the name Yak-41 was introduced for the aircraft. State tests were scheduled for 1982.

"Yakovlevtsy" could well meet the proposed deadlines, since by 1980 the main issues related to the layout and on-board equipment had been resolved. The State Commission positively assessed the full-size model of the fighter, and it was already about the manufacture of the first four aircraft, intended mainly for various experimental work.

But the creation of a lift-and-flight engine was delayed. The design of a fundamentally new nozzle caused particular difficulties - there were no such designs in any country of the world at that time. As a result, state tests were postponed first to 1985, and then to 1987.

The first flight of the future Yak-41 vertical take-off fighter was made on March 9, 1987, and this time it took off and landed like a regular plane - with a takeoff run and run. By this time, the car (at the special request of the Ministry of Defense) was somewhat redone - they tried to make it multi-purpose. The test cycle was noticeably delayed: the deteriorating financial situation of the USSR had an effect. In addition, back in 1984, D.F. Ustinov, who was perhaps the main supporter of vertical take-off aircraft, died - the project was left without a "patron".

In 1989, the fighter was renamed the Yak-141. This decision was due to the frank disruption of all previously designated deadlines for the aircraft creation program. Oddly enough, the name change helped to some extent - at the end of the same year, vertical take-off and hover was first tested. On June 13, 1990, the Yak-141 finally made its first full-fledged flight - it took to the air without a run, performed piloting, and then returned to its starting point and landed without a run.

By the autumn of 1991, everything was ready for testing on the "regular" ship for the new fighter - the heavy aircraft carrier cruiser "Admiral Gorshkov" (the first name was "Baku"). The first flights were successful, however, on October 5, the Yak-141 crashed while landing. The pilot ejected and was rescued, but this incident led to the closure of the aircraft program.

In other conditions, everything could be different, but the USSR was already dying - two months later the country collapsed. Leaders " new Russia"And" independent Ukraine ", as you might guess, did not show any interest in the Yak-141. In 1992, the fighter was shown at the Farnborough Air Show, and this became its "swan song". Attempts to find foreign buyers were unsuccessful, so the promising aircraft turned into a museum exhibit. All four aircraft carriers built for it were withdrawn from the Navy. One of them was cut up for scrap, the other two were turned into "entertainment technical parks", and only the former "Admiral Gorshkov" continues to serve, but not in the Russian, but in the Indian fleet.

Design features

There are three main fundamental differences between the Yak-141 fighter and all conventional "horizontal" aircraft:

1. Combined power plant with rotary engine nozzles;
2. jet rudders;
3. Automatic ejection system.

It is these features that allow the machine to perform a fully vertical or short takeoff, while providing the necessary level of safety for the pilot.

Glider

When creating the aircraft, the designers chose a normal aerodynamic configuration. At the same time, the Yak-141 differs markedly from its predecessor, the Yak-38 attack aircraft, primarily in the location of the wing - the new aircraft has become a high-wing aircraft. The main material used in the manufacture of the airframe is alloys based on aluminum and lithium. They make up almost 74% by weight. The rest falls mainly (26%) on composite materials. Individual parts are made of titanium-based alloys resistant to impact high temperature, as well as from hardened steel.

Fuselage

The nose of the fuselage was used to accommodate the Zhuk radar and the cockpit closed with a pointed radome. Next up is the lift engine compartment and fuel tanks. The tail contains the main engine and a small parachute compartment (can be used in a "horizontal" landing to reduce range). When designing the fuselage, the area rule was taken into account.

Wing

The Yak-141 is a supersonic aircraft, which is ensured, in particular, by the trapezoidal wing shape chosen for this machine, on the trailing edge of which there is a break, and at the root there are sagging. The mechanization consists of flaps, elevons (a control that acts as an aileron and an elevator at the same time) and rotary socks. The wing is made folding, which simplifies the transportation of the fighter and its placement in a small area.

Tail unit

Yak-141 has two keels. They are installed with a slight angle of inclination on cantilever beams located at the rear of the aircraft, on both sides of the main engine nozzle and carried back a fairly large distance. The keels are equipped with rudders. In addition, the tail assembly includes two all-moving stabilizers. They are installed slightly below the longitudinal line of the wing.

Air intakes

To provide the lift-main engine with the necessary air volume during takeoff, adjustable rectangular air intakes are equipped with special side valves.

In vertical take-off mode, to increase engine efficiency, transverse flaps (partitions) are used, which extend under the air intakes and help to avoid the recirculation of air jets. In order for hot gases to better break away from the fuselage, there are special longitudinal partitions on the sides of the air intakes, in their lower part.

Chassis

The aircraft is able to withstand a fall "flat" from a height of five meters. This is provided by tricycle chassis. All supports are single-wheeled. The cleaning of the main racks is carried out under the air intake channels, forward along the flight. The front wheel retracts in the opposite direction, into the fuselage niche.

Power point

Yak-141 is equipped with three engines. Two of them (lifting) are switched on only during takeoff and landing, the third, the main one (lifting and marching), works throughout the entire flight.

Lifting and propulsion engine

Especially for the Yak-141 multi-purpose aircraft, Soyuz AMNTK created the R79V-300 lift-and-flight engine with a thrust vector deflected in the vertical plane, which is provided by a nozzle that can be turned down, up to an angle of 95 degrees. The cross-sectional area of ​​the nozzle is adjustable. In the afterburner, this engine creates a thrust of 15,500 kgf.

The nozzle rotation mechanism has a resource of one and a half thousand cycles (this is the minimum estimate). The engine provides a fully vertical, short and ultra-short takeoff. In the last two cases, the angle of rotation of the nozzle should be 65 degrees. It should be noted that a takeoff with a range, even the shortest one, can significantly increase the mass of the payload and increase the combat radius.

Lift motors

The fighter is equipped with two RD-41 lifting engines, which were created in the Rybinsk Motor Design Bureau. For their placement, a special compartment is used, located directly behind the cab. Thanks to the use of a special device attached to the nozzle of each of the engines, it is possible to deflect the longitudinal thrust vector at angles in the range from -12.5 to +12.5 degrees.

To form a single jet stream during takeoff, the takeoff engines turn towards each other. In level flight, they are turned off, and the compartment provided for them is automatically closed by special shutters (on the ground they are also in the closed position).

The possibility of using lifting engines to perform various evolutions in the air was envisaged, however, this is only possible when flying at a speed of 550 km / h or less.

jet rudders

Since it is not possible to use conventional controls during vertical takeoff and landing, the Yak-141 is equipped with jet rudders - small nozzles that are located in the wingtips and in the front of the fuselage. With their help, you can change the angle of roll and direction (course). In order to raise or lower the nose of a fighter, the pilot can vary the ratio of the thrust of the lift-cruise and lift engines.

fuel tanks

Approximately in the middle of the Yak-141 fuselage are internal fuel tanks. In addition, fuel is also placed in the rear of the hull, inside each of the tail booms. Additional external tanks can be installed on standard attachment points located under the wing, and a place for another tank (conformal, 2000 liters) is located under the fuselage.

Airborne equipment and systems

Several main types of aircraft equipment are installed on board the fighter, designed to control the aircraft, navigate, search for targets and aim guided missiles at them, as well as to perform various control functions. All this equipment is distributed in three compartments, one of which is located in the tail, the other - in the front of the fuselage and the third - close to the air intakes.

Electronic and sighting equipment

The main part of the weapons control system is the Zhuk radar, slightly modified compared to the version that was installed on the MiG-29 fighters. Reducing the diameter of the main antenna, caused by the need to “fit” the radar into the contours of the Yak-141 fuselage, somewhat reduced the characteristics of the radar, while it is still capable of detecting targets the size of F-16 at an eighty-kilometer distance.

Enemy ships, including boats, the Zhuk can detect at a distance of up to 110 kilometers. Automatic tracking of ten targets is provided with simultaneous firing of four of them. Data processing is carried out by the on-board computer.

Yak-141 uses active jamming. The devices necessary for this are located on the tips of the wing consoles and in the upper part of each of the keels. It was also supposed to equip the aircraft with a device for emitting passive interference.

The antenna, located in front of the cab, is part of the "Password" system used for state identification.

Flight and navigation complex

Although the GLONASS system did not yet exist in the 80s, the Yak was already adapted for its use. When performing test flights, a conventional inertial system was used to solve navigation problems. In addition, there was equipment for landing on the deck of the ship in automatic mode.

The main control system is electrically remote. With its help, not only plumage is controlled, but also jet rudders. A mechanical control was also installed, which could be used in emergency situations.

Communication and guidance complex

The Yak-141 pilot is provided with the opportunity to communicate with ground guidance points and other aircraft both in the decimeter and in the meter wavelength range. For each of them on board there is a special radio station. In addition, equipment was installed, with the help of which communications were encrypted.

Power supply system

Backup sources of electricity for the Yak-141 are two batteries. Main power is provided by generators connected to the main engine. The set of equipment also includes two rectifiers and static converters.

Registration, control and signaling equipment

The left tail boom of the fighter is used to install a flight recorder that records everything that happens during the flight. Checking the health of the equipment is carried out by a special control automated system. There is also an alarm system that notifies the pilot of the occurrence of dangerous or emergency situations.

Cabin Yak-141

The rescue of the pilot is provided by the K-36LV seat located in the cockpit, which can be activated both by the pilot himself and by automation. The lantern is made of Plexiglas and has a flat front piece made of transparent armor. The display of flight information was supposed to be carried out on multifunctional indicators, the same as on the MiG-29, but they simply did not have time to install them. Nevertheless, the HUD (a device for projecting flight information onto the plane of the windshield) already existed. It was also envisaged to use a helmet-mounted target designation system.

Flight performance

The range is given for flight under a load of one ton with a short takeoff and landing. Using the aircraft in vertical lift mode reduces the combat radius. In this case, even without load, the range of the Yak-141 is reduced to 1400 km at high altitude, and to 650 km when flying close to the ground.

Tactical and technical characteristics

Project development

After 1992, no further work on the Yak-141 aircraft was carried out. Foreign customers did not need this fighter either, apparently because of its specificity. In a word, this unusual winged car became a victim of "democratization".

Only representatives of the American company Lockheed Martin showed some interest in the fighter. Unfortunately, all "cooperation" actually came down to export to the United States technical documentation. Apparently, it was then used in the development of the deck version of the F-35 aircraft. In any case, the individual elements of this machine are similar to the Yak-141.

The government remembered the failed carrier-based fighter for the last time in 2017, when the Deputy Minister of Defense stated that it was necessary to develop short takeoff and landing aircraft “like the Yak”.

Most likely, there is nothing behind these words, because it is too late to revive the old machine, and it is expensive to create a new one, not to mention the fact that it will require the construction of new ships. True, plans for their creation were also voiced, but then all talk stopped.

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The design of aircraft with vertical takeoff and landing is associated with great difficulties associated with the need to create light engines, controllability at near-zero speeds, etc.

Currently, there are many projects of vertical takeoff and landing aircraft, many of which have already been implemented in real vehicles.

Aircraft with propellers

One of the solutions to the problem of vertical takeoff and landing is the creation of an aircraft in which the lift force during takeoff and landing is created by turning the axis of rotation of the propellers, and in horizontal flight - by the wing. Turning the axis of rotation of the propellers can be achieved by turning the engine or wing. The wing of such an aircraft (Fig. 160) is made according to a multi-spar scheme (at least two spars) and is hinged to the fuselage. The wing turning mechanism is most often a screw jack with synchronized rotation, which provides a change in the wing installation angle by an angle of more than 90 °.

The wing is equipped throughout the span with multi-slotted flaps. In areas where the wing is not blown by the air flow from the propeller, or where the blowing speeds are low (in the central part of the wing), slats are installed to help eliminate flow stall at high angles of attack. The vertical tail is relatively large (to improve directional stability at low flight speeds) and is equipped with a rudder. The stabilizer of such an aircraft is usually controlled. The angles of installation of the stabilizer can vary within wide limits, providing the transition of the aircraft from vertical takeoff to horizontal flight and vice versa. The base of the keel passes into a tail boom carried back, on which a small-diameter, variable-pitch tail rotor is mounted in a horizontal plane, providing longitudinal control in hovering and transient flight modes.

The power plant consists of several powerful turboprop engines, which are small in size and have a low specific gravity of about 0.114 kg / l. s., which is very important for aircraft vertical takeoff and landing of any scheme, since such devices during vertical takeoff must have more thrust than weight. In addition to overcoming weight, thrust must overcome aerodynamic resistance and create acceleration to accelerate the aircraft to a speed at which the wing lift will fully compensate for the weight of the aircraft, and the control airfoils will be sufficiently effective.

A serious design flaw of VTOL aircraft with propellers is that ensuring flight safety and reliable controllability of the aircraft during vertical takeoff and in transitional flight modes is achieved at the cost of weighting and complicating the design through the use of a wing turning mechanism and a transmission that synchronizes the rotation of propellers. .

The aircraft control system is also complex. Control during takeoff and landing and in cruise flight along three axes is carried out using conventional aerodynamic control surfaces, but in hover and. transition modes before and after cruising, other control methods are used.

During vertical climb, longitudinal control is carried out using a horizontal tail rotor (with variable pitch) located behind the keel (Fig. 160, b), directional control is carried out by differential deflection of the end sections of the flaps blown by a jet from propellers, and lateral control is differential changing the pitch of the extreme propellers.

In the transitional mode, a gradual transition to control using conventional surfaces is carried out; for this, a command mixer is used, the operation of which is programmed depending on the angle of rotation of the wing. The control system includes a stabilization mechanism.

Improving the performance of VTOL aircraft with propellers is currently possible due to the fact that the propeller is enclosed in an annular channel (a short pipe of the appropriate diameter). Such a propeller develops thrust by 15-20% more than propeller thrust without a "fence". This is explained by the fact that the walls of the channel prevent the flow of compressed air from the lower surfaces of the screw to the upper ones, where the pressure is reduced, and exclude the dispersion of the flow from the screw to the sides. In addition, when air is sucked in by the screw above the annular channel, a low pressure area is created, and since the screw throws down the compressed air flow, the pressure difference on the upper and lower cuts of the channel ring leads to the formation of additional lifting force. On fig. 161, and shows a diagram of a vertical takeoff and landing aircraft with propellers installed in the annular channels. The aircraft is made according to the tandem scheme with four propellers driven by a common transmission.

Three-axis control in cruising and vertical flight (Fig. 161, b, c, d) is carried out mainly by differentially changing the pitch of the propellers and deflecting the flaps located horizontally in the jets thrown by the propellers behind the channels.

It should be noted that VTOL aircraft with propellers are capable of speeds of 600-800 km/h. Achieving higher subsonic, and even more so supersonic flight speeds is possible only with the use of jet engines.

Jet-powered aircraft

There are many schemes of vertical takeoff and landing aircraft with reactive thrust, but they can be quite strictly divided into three main groups according to the type of power plant: aircraft with a single power plant, with a composite power plant and with a power plant with thrust amplification units.

Planes with a single power plant, in which the same engine creates vertical and horizontal thrust (Fig. 162), can theoretically fly at speeds several times greater than the speed of sound. A serious disadvantage of such an aircraft is that an engine failure during takeoff or landing threatens with disaster.

An aircraft with a composite power plant can also fly at supersonic speeds. Its power plant consists of engines designed for vertical takeoff and landing (elevating) and engines for horizontal flight (marching), fig. 163.

Lifting engines have a vertically located axis, and marching engines have a horizontally located one. Failure of one or two lift engines during takeoff allows vertical takeoff and landing to continue. TRD, DTRD can be used as marching engines. Propulsion engines on takeoff may also be involved in the creation of vertical thrust. The thrust vector is deflected either by rotary nozzles or by turning the engine along with the nacelle.

On planes with GDP jet engines stability and controllability in take-off, landing, hovering and transitional modes, when aerodynamic forces are absent or small in magnitude, is provided by gas-dynamic type control devices. According to the principle of operation, they are divided into three classes: with the selection of compressed air or hot gases from the power plant, using the magnitude of the propulsion thrust and using devices for deflecting the thrust vector.

Control devices with the selection of compressed air or gases are the most simple and reliable. An example of the layout of the control device with the selection of compressed air from lifting motors is shown in fig. 164.

Airplanes equipped with a power plant with thrust amplification units can have turbofan units (Fig. 165) or gas ejectors (Fig. 166), which create the necessary vertical thrust on takeoff. The power plants of these aircraft can be created on the basis of turbojet and diesel turbojet engines.

The power plant of the aircraft with thrust amplification units, shown in fig. 165, consists of two turbojet engines installed in the fuselage and creating horizontal thrust. During vertical takeoff and landing, turbojet engines are used as gas generators to drive two turbines with fans located in the wing, and one turbine with a fan in the forward fuselage. The front fan is only used for longitudinal control.

Aircraft control in vertical modes is provided by fans, and in level flight - by aerodynamic rudders. An aircraft with an ejector power plant, shown in fig. 166, has a power plant of two turbojet engines. To create vertical thrust, the gas flow is directed to an ejector device located in the central part of the fuselage. The device has two central air channels, from which the air is directed to the transverse channels with slotted nozzles at the ends.

Each turbojet is connected to one central channel and half of the transverse channels with nozzles, so that when one turbojet is turned off or fails, the ejector device continues to work. The nozzles go into the ejector chambers, which are closed by shutters on the upper and lower surfaces of the fuselage. During the operation of the ejector installation, the gases flowing out of the nozzle eject air, the volume of which is 5.5-6 times greater than the volume of gases, which is 30% higher than the thrust of the turbojet engine.

The gases flowing out of the ejector chambers have a low speed and temperature. This allows the aircraft to be operated from runways without special coating, in addition, the ejector device reduces the noise level of the turbojet engine. Aircraft control in cruise mode is carried out by conventional aerodynamic surfaces, and in takeoff, landing and transitional modes - by a system of jet rudders that ensure stability and controllability of the aircraft.

Thrust vectoring power plants have several very serious drawbacks. Thus, a power plant with a turbofan unit requires large volumes to accommodate the fans, which makes it difficult to create a wing with a thin profile that normally operates in a supersonic flow. Even larger volumes require an ejector power plant.

Typically, such schemes have difficulties with the placement of fuel, which limits the range of the aircraft.

When considering the schemes of aircrafts of the VVP, an erroneous opinion may arise that the possibility of vertical take-off should pay off by reducing the payload lifted by the aircraft. Even approximate calculations support the conclusion that a vertical take-off aircraft with high flight speed can be created without significant losses in payload or range if the requirements of vertical take-off and landing are taken as the basis from the very beginning of aircraft design.

On fig. 167 shows the results of the analysis of the weights of conventional aircraft (normal takeoff) and GDP. Airplanes of equal takeoff weight are compared, having the same cruising speed, altitude, range and lifting the same payload. From the diagram in fig. 167 can be seen, but the VTOL aircraft (with 12 lift engines) has a power plant heavier than a conventional aircraft by about 6% of the takeoff weight of a normal takeoff aircraft.

In addition, lift engine nacelles add another 3% of the takeoff weight to the weight of the aircraft structure. Fuel consumption for takeoff and landing, including movement on the ground, is 1.5% more than that of a conventional aircraft, and the weight additional equipment aircraft GDP by 1%.

This additional weight, which is inevitable for a vertically taking off aircraft, equal to about 11.5% of the takeoff weight, can be compensated by reducing the weight of other elements of its structure.

So, for the aircraft of the VVP, the wing is made smaller in comparison with the aircraft of the usual scheme. In addition, there is no need for wing mechanization, and this reduces the weight by about 4.4%.

Further savings in aircraft weight can be expected from a reduction in the weight of the landing gear and tail unit. The weight of the undercarriage of a runway aircraft, designed for a maximum sink rate of 3 m/s, can be reduced by 2% of the takeoff weight compared to a conventional aircraft.

Thus, the weight balance of a runway aircraft shows that the weight of the runway aircraft structure is greater than the weight of a conventional aircraft by approximately 4.5% of the maximum takeoff weight of a conventional aircraft.

However, a conventional aircraft must have a significant reserve of fuel for holding operations and for searching for an alternate aerodrome in bad weather. This reserve of fuel for a vertically taking off aircraft can be greatly reduced, since it does not need a runway and can land on almost any site, which may be small in size.

From the foregoing, it follows that an aircraft with a takeoff weight of the same as that of a conventional aircraft can carry the same payload and fly at the same speed and for the same range.

Used literature: "Fundamentals of Aviation" authors: G.A. Nikitin, E.A. Bakanov

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