Supersonic civil aircraft. Steep dive. History of supersonic airlinersPlot. A supersonic plane takes to the skies
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Story [ | ]
Although most combat aircraft are capable of supersonic speed, many are not designed for supersonic cruising, and only a few can achieve this speed in level flight without engine afterburner.
Passenger supersonic aircraft[ | ]
There are only two known mass-produced passenger supersonic aircraft that performed regular flights: the Soviet aircraft Tu-144, which made its first flight on December 31, 1968 and was in operation from 1975 to 1978, and which flew two months later; the Anglo-French Concorde, which made transatlantic and charter flights from 1976 to 2003. They significantly reduced the time of long-distance flights, used unloaded air space(≈18 km) above the usual altitude of 9-12 km, where flights were made outside airways.
The most significant disadvantages of commercial supersonic aircraft were:
Despite the non-implementation of several other former and existing projects of passenger supersonic and transonic aircraft (Boeing 2707, Boeing Sonic Cruiser, Douglas 2229, Tu-244, Tu-344, Tu-444, SSBJ, etc.) and the decommissioning of aircraft from two completed projects , were developed earlier and there are modern projects of hypersonic (including suborbital) passenger airliners (for example, ZEHST, SpaceLiner) and military transport () rapid response aircraft.
In November 2015, a firm order was placed for the AS2 passenger business jet under development for 20 units with a total cost of $2.4 billion with deliveries to begin in 2023.
Theoretical problems[ | ]
Flight at supersonic speed, in contrast to subsonic speed, takes place in conditions of different aerodynamics, since when the aircraft reaches the speed of sound, the aerodynamics of the flow change qualitatively, due to which the aerodynamic drag sharply increases, and the kinetic heating of the structure from the friction of the oncoming air also increases. high speed air flow, the aerodynamic focus shifts, which leads to a loss of stability and controllability of the aircraft. In addition, such a phenomenon, unknown before the creation of the first supersonic aircraft, as “wave drag” appeared.
Therefore, achieving the speed of sound and effective stable flight at near- and supersonic speeds were impossible by simply increasing engine power - new design solutions were required. As a result, the appearance of the aircraft changed: characteristic straight lines and sharp corners appeared, in contrast to the “smooth” shapes of subsonic aircraft.
It should be noted that the problem of creating an effective supersonic aircraft cannot still be considered resolved. The creators have to make a compromise between the requirement to increase speed and maintain acceptable takeoff and landing characteristics. Thus, the conquest of new frontiers in speed and altitude by aviation is associated not only with the use of a more advanced or fundamentally new propulsion system and a new structural layout of aircraft, but also with changes in their geometry in flight. Such changes, while improving the aircraft's performance at high speeds, should not worsen their performance at low speeds, and vice versa. Recently, creators have abandoned reducing the wing area and the relative thickness of their profiles, as well as increasing the wing sweep angle of aircraft with variable geometry, returning to low-sweep wings and a large relative thickness, if satisfactory maximum speed and service ceiling values have already been achieved. In this case, it is considered important that a supersonic aircraft have good performance at low speeds and low drag at high speeds, especially at low altitudes.
“Turn on supersonic!”
Supersonic passenger aircraft - what do we know about them? At least that they were created relatively long ago. But, for various reasons, they were not used for as long and not as often as they could have. And today, they exist only as design models.
Why is that? What is the peculiarity and “secret” of supersonic sound? Who created this technology? And also - what will be the future of supersonic aircraft in the world, and of course - in Russia? We will try to answer all these questions.
"Farewell flight"
So, fifteen years have passed since the last three functioning supersonic passenger aircraft made their last flights, after which they were written off. This was back in 2003. Then, on October 24, they all together “said goodbye to the sky.” The last time we flew at low altitude, over the capital of Great Britain.
Then we landed at London Heathrow Airport. These were Concorde-type aircraft owned by the aviation company British Airways. And with such a “farewell flight” they ended a very short history of passenger transportation at speeds exceeding sound...
That's what you might have thought a few years ago. But now it is already possible to say with confidence. This is the finale of only the first stage of this story. And probably all its bright pages are yet to come.
Today - preparation, tomorrow - flight
Today, many companies and aircraft designers are thinking about the prospects of supersonic passenger aviation. Some are making plans to revive it. Others are already preparing for this with all their might.
After all, if it could exist and function effectively just a few decades ago, today, with technologies that have seriously stepped forward, it is quite possible not only to revive it, but also to solve a number of problems that forced leading airlines to abandon it.
And the prospects are too tempting. The possibility of flying, say, from London to Tokyo in five hours seems very interesting. Cross the distance from Sydney to Los Angeles in six hours? And get from Paris to New York in three and a half? With passenger aircraft, which are capable of flying at higher speeds than sound travels, this is not at all difficult.
But, of course, before its triumphant “return” to the airspace, scientists, engineers, designers, and many others still have a lot of work to do. It's not just about restoring what once was by offering a new model. Not at all.
The goal is to solve many problems associated with passenger supersonic aviation. Creation of aircraft that will not only demonstrate the capabilities and power of the countries that built them. But they will also turn out to be really effective. So much so that they occupy a worthy niche in aviation.
History of "supersonic" Part 1. What happened in the beginning...
Where did it all begin? In fact - from simple passenger aviation. And he has been like this for more than a century. Its design began in the 1910s in Europe. When craftsmen from the most developed countries of the world created the first aircraft, the main purpose of which was to transport passengers over various distances. That is, a flight with many people on board.
The first among them is the French Bleriot XXIV Limousine. It belonged to the aircraft manufacturing company Bleriot Aeronautique. However, it was used mainly for the amusement of those who paid for pleasure “walks”-flights on it. Two years after its creation, an analogue appears in Russia.
It was the S-21 Grand. It was designed on the basis of the Russian Knight, a heavy bomber created by Igor Sikorsky. And the construction of this passenger aircraft was carried out by workers of the Baltic Carriage Plant.
Well, after that, progress could no longer be stopped. Aviation developed rapidly. And the passenger one, in particular. At first there were flights between specific cities. Then the planes were able to cover distances between states. Finally, aircraft began to cross oceans and fly from one continent to another.
Developing technologies and an increasing number of innovations allowed aviation to travel very quickly. Much sooner than trains or ships. And for her there were practically no barriers. There was no need to change from one transport to another, not only, say, when traveling to some particularly distant “end of the world”.
Even when it is necessary to cross land and water at once. Nothing stopped the planes. And this is natural, because they fly over everything - continents, oceans, countries...
But time was passing quickly, the world was changing. Of course, the aviation industry also developed. Airplanes over the next few decades, right up to the 1950s, changed so much when compared with those that flew back in the early 1920s and 30s that they became something completely different, special.
And so, in the middle of the twentieth century, the development of the jet engine began at a very rapid pace, even in comparison with the previous twenty to thirty years.
A small informational digression. Or - a little physics
Advanced developments have allowed aircraft to “accelerate” to speeds greater than the speed at which sound travels. Of course, first of all, this was applied in military aviation. After all, we are talking about the twentieth century. Which, sad to say, was a century of conflicts, two world wars, the “cold” struggle between the USSR and the USA...
And almost every new technology created by the leading states of the world was primarily considered from the point of view of how it could be used in defense or attack.
So, airplanes could now fly at unprecedented speeds. Faster than sound. What is its specificity?
First of all, it is obvious that this is a speed that exceeds the speed at which sound travels. But, remembering the basic laws of physics, we can say that in different conditions, it may differ. And “exceeds” is a very loose concept.
And that’s why there is a special standard. Supersonic speed is one that exceeds sound speed up to five times, taking into account the fact that depending on temperature and other environmental factors, it can change.
For example, if we take normal atmospheric pressure at sea level, then in this case, the speed of sound will be equal to an impressive figure - 1191 km/h. That is, 331 meters are covered in a second.
But what is especially important when designing supersonic aircraft is that as you gain altitude, the temperature decreases. This means the speed with which sound travels is quite significant.
So let's say, if you rise to a height of 20 thousand meters, then here it will already be 295 meters per second. But there is another important point.
At 25 thousand meters above sea level, the temperature begins to rise, since this is no longer the lower layer of the atmosphere. And so it goes on. Or rather, higher. Let's say at an altitude of 50,000 meters it will be even hotter. Consequently, the speed of sound there increases even more.
I wonder - for how long? Having risen 30 kilometers above sea level, you find yourself in a “zone” where sound travels at a speed of 318 meters per second. And at 50,000 meters, respectively - 330 m/s.
About the Mach number
By the way, it is interesting that to simplify the understanding of the features of flight and work in such conditions, the Mach number is used in aviation. general description such, can be reduced to the following conclusions. It expresses the speed of sound that occurs under given conditions, at a particular altitude, at a given temperature and air density.
For example, the flight speed, which is equal to two Mach numbers, at an altitude of ten kilometers above the ground, under normal conditions, will be equal to 2,157 km/h. And at sea level - 2,383 km/h.
History of "supersonic" Part 2. Overcoming barriers
By the way, for the first time a pilot from the USA, Chuck Yeager, achieved flight speeds of more than Mach 1. This happened in 1947. Then he “accelerated” his plane, flying at an altitude of 12.2 thousand meters above the ground, to a speed of 1066 km/h. This is how the first supersonic flight took place on earth.
Already in the 1950s, work began on the design and preparation for mass production of passenger aircraft capable of flying at speeds faster than sound. They are led by scientists and aircraft designers from the most powerful countries in the world. And they manage to succeed.
That same Concorde, a model that will finally be abandoned in 2003, was created in 1969. This is a joint British-French development. The symbolically chosen name is “Concorde”, from French, translated as “concord”.
It was one of two existing types of supersonic passenger aircraft. Well, the creation of the second (or rather, chronologically, the first) is the merit of the aircraft designers of the USSR. The Soviet equivalent of the Concorde is called the Tu-144. It was designed in the 1960s and made its first flight on December 31, 1968, a year before the British-French model.
To this day, no other types of supersonic passenger aircraft have been implemented. Both the Concorde and the Tu-144 flew thanks to turbojet engines, which were specially rebuilt in order to operate at supersonic speed for a long time.
The Soviet analogue of the Concorde was operated for a significantly shorter period. Already in 1977 it was abandoned. The plane flew at an average speed of 2,300 kilometers per hour and could carry up to 140 passengers at a time. But at the same time, the price of a ticket for such a “supersonic” flight was two, two and a half, or even three times more than for an ordinary one.
Of course, such things were not in great demand among Soviet citizens. And maintaining the Tu-144 was not easy and expensive. That’s why they were abandoned so quickly in the USSR.
Concordes lasted longer, although tickets for the flights they flew were also expensive. And the demand was not great either. But still, despite this, they continued to be exploited, both in Great Britain and in France.
If you recalculate the cost of a Concorde ticket in the 1970s at today's exchange rate, it will be about two tens of thousands of dollars. For a one way ticket. One can understand why the demand for them was somewhat less than for flights using aircraft that do not reach supersonic speeds.
Concorde could carry from 92 to 120 passengers at a time. He flew at a speed of more than 2 thousand km/h and covered the distance from Paris to New York in three and a half hours.
Several decades passed like this. Until 2003.
One of the reasons for the refusal to operate this model was a plane crash that occurred in 2000. At that time, there were 113 people on board the crashed Concorde. They all died.
Later, an international passenger crisis began. air transportation. Its cause is the terrorist attacks that occurred on September 11, 2001, in the United States.
Moreover, the warranty period for Concorde service by Airbus is ending. All this together made the further operation of supersonic passenger aircraft extremely unprofitable. And in 2003, all Concordes were written off one by one, both in France and in the UK.
Hopes
After this, there were still hopes for a quick “return” of supersonic passenger aircraft. Aircraft designers talked about creating special engines that would save fuel, despite the flight speed. We talked about improving the quality and optimizing the main avionics systems on such aircraft.
But, in 2006 and 2008, new resolutions of the International Organization were issued civil aviation. They determined the latest (by the way, they are still valid at the moment) standards for permissible aircraft noise during flight.
And supersonic planes, as you know, did not have the right to fly over populated areas, that’s why. After all, they produced strong noise pops (also due to the physical characteristics of the flight) when they moved at maximum speeds.
This was the reason that the “planning” of the “revival” of supersonic passenger aviation was somewhat slowed down. However, in fact, after the introduction of this requirement, aircraft designers began to think about how to solve this problem. After all, it also took place before, it’s just that the “ban” focused attention on it - the “noise problem”.
What about today?
But ten years have passed since the last “ban”. And planning smoothly turned into design. Today, several companies and government organizations are engaged in the creation of passenger supersonic aircraft.
Which ones exactly? Russian: Central Aerohydrodynamic Institute (the same one that is named after Zhukovsky), Tupolev and Sukhoi companies. Russian aircraft designers have an invaluable advantage.
The experience of Soviet designers and creators of the Tu-144. However, it is better to talk about domestic developments in this area separately and in more detail, which is what we propose to do next.
But it’s not just the Russians who are creating a new generation of supersonic passenger aircraft. This is also a European concern - Airbus, and the French company Dassault. Among the companies in the United States of America that are working in this direction are Boeing and, of course, Lockheed Martin. In the country rising sun The main organization designing such an aircraft is the Aerospace Exploration Agency.
And this list is by no means complete. It is important to clarify that the overwhelming majority of professional aircraft designers working in this field are divided into two groups. Regardless of country of origin.
Some believe that it is in no way possible to create a “quiet” supersonic passenger aircraft at the current level of technological development of mankind.
Therefore, the only way out is to design a “simply fast” airliner. It, in turn, will go to supersonic speed in those places where this is allowed. And when flying, for example, over populated areas, return to subsonic.
Such “jumps,” according to this group of scientists and designers, will reduce flight time to the minimum possible, and not violate the requirements for noise effects.
Others, on the contrary, are full of determination. They believe that it is possible to fight the cause of the noise now. And they made a lot of effort to prove that it is quite possible to build a supersonic airliner that flies quietly in the very coming years.
And a little more fun physics
So, when flying at a speed of more than Mach 1.2, the airframe of the aircraft generates shock waves. They are strongest in the tail and nose areas, as well as some other parts of the aircraft, such as the edges of the air intakes.
What is a shock wave? This is an area where air density, pressure and temperature experience sudden changes. They occur when moving at high speeds, faster than sound speed.
To people who are standing on the ground, despite the distance, it seems that some kind of explosion is happening. Of course, we are talking about those who are in relative proximity - under the place where the plane flies. That is why flights were banned supersonic aviation over cities.
It is precisely such shock waves that representatives of the “second camp” of scientists and designers are fighting against, who believe in the possibility of leveling out this noise.
If we go into detail, the reason for this is literally a “collision” with air at a very high speed. At the wave front there is a sharp and strong increase in pressure. At the same time, immediately after it, there is a drop in pressure, and then a transition to a normal pressure indicator (the same as it was before the “collision”).
However, a classification of wave types has already been carried out and potentially optimal solutions have been found. All that remains is to complete the work in this direction and make the necessary adjustments to the aircraft designs, or create them from scratch, taking into account these amendments.
In particular, NASA specialists came to realize the need for structural changes in order to reform the characteristics of the flight as a whole.
Namely, changing the specifics of shock waves, as far as possible at the current technological level. What is achieved by restructuring the wave, through specific design changes. As a result, the standard wave is considered as an N-type, and the one that occurs during flight, taking into account the innovations proposed by experts, as an S-type.
And with the latter, the “explosive” effect of pressure changes is significantly reduced, and people located below, for example, in a city, if an airplane flies over them, even when they hear such an effect, it is only like a “distant slam of a car door.”
Shape is also important
In addition, for example, Japanese aviation designers, not so long ago, in mid-2015, created an unmanned glider model D-SEND 2. Its shape is designed in a special way, allowing to significantly reduce the intensity and number of shock waves that occur when the device flies at supersonic speed.
The effectiveness of the innovations proposed in this way by Japanese scientists was proven during tests of D-SEND 2. These were carried out in Sweden in July 2015. The course of the event was quite interesting.
The glider, which was not equipped with engines, was raised to a height of 30.5 kilometers. By using hot air balloon. Then he was thrown down. During the fall, he “accelerated” to a speed of Mach 1.39. The length of D-SEND 2 itself is 7.9 meters.
After the tests, Japanese aircraft designers were able to confidently declare that the intensity of the shock waves when their brainchild flies at a speed exceeding the speed of sound propagation is two times less than that of the Concorde.
What are the features of D-SEND 2? First of all, its bow is not axisymmetric. The keel is shifted towards it, and at the same time, the horizontal tail unit is installed as all-moving. It is also located at a negative angle to the longitudinal axis. And at the same time, the tail tips are located lower than the attachment point.
The wing, smoothly connected to the fuselage, is made with normal sweep, but stepped.
According to approximately the same scheme, now, as of November 2018, the supersonic passenger AS2 is being designed. Professionals from Lockheed Martin are working on it. The customer is NASA.
Also, the Russian SDS/SPS project is now at the stage of improving its form. It is planned that it will be created with an emphasis on reducing the intensity of shock waves.
Certification and... another certification
It is important to understand that some projects of passenger supersonic aircraft will be implemented in the early 2020s. At the same time, the rules established by the International Civil Aviation Organization in 2006 and 2008 will still be in force.
This means that if before that time there is no serious technological breakthrough in the field of “quiet supersonic”, then it is likely that aircraft will be created that will reach speeds above one Mach only in zones where this is permitted.
And after that, when the necessary technologies do appear, in such a scenario, many new tests will have to be carried out. In order for aircraft to obtain permission to fly over populated areas. But these are only speculations about the future; today it is very difficult to say anything for sure on this matter.
Question of price
Another problem mentioned earlier is the high cost. Of course, today, many engines have already been created that are much more economical than those that were used twenty or thirty years ago.
In particular, those that can provide aircraft movement at supersonic speed are now being designed, but at the same time do not “eat up” as much fuel as the Tu-144 or Concorde.
How? First of all, this is the use of ceramic composite materials, which reduce temperatures, and this is especially important in hot zones of power plants.
In addition, the introduction of another, third, air circuit - in addition to the external and internal ones. Leveling the rigid coupling of a turbine with a fan, inside an aircraft engine, etc.
But nevertheless, even thanks to all these innovations, it cannot be said that supersonic flight, in today's realities, is economical. Therefore, in order for it to become accessible and attractive to the general public, work to improve engines is extremely important.
Perhaps the current solution would be a complete redesign of the design, experts say.
By the way, it will also not be possible to reduce the cost by increasing the number of passengers per flight. Because those aircraft that are being designed today (meaning, of course, supersonic aircraft) are designed to transport a small number of people - from eight to forty-five.
A new engine is a solution to the problem
Among the latest innovations in this area, it is worth noting the innovative jet turbofan power plant created this year, 2018, by GE Aviation. In October it was introduced under the name Affinity.
This engine is planned to be installed on the mentioned AS2 passenger model. There are no significant technological “new products” in this type of power plants. But at the same time, it combines the features of jet engines with high and low bypass ratios. Which makes the model very interesting for installation on a supersonic aircraft.
Among other things, the creators of the engine claim that during testing it will prove its ergonomics. The fuel consumption of the power plant will be approximately equal to that which can be recorded for standard airliner engines currently in operation.
That is, this is a claim that the power plant of a supersonic aircraft will consume approximately the same amount of fuel as a conventional airliner that is not capable of accelerating to speeds above Mach one.
How this will happen is still difficult to explain. Since the design features of the engine are not currently being disclosed by its creators.
What could they be - Russian supersonic airliners?
Of course, today there are many specific projects for supersonic passenger aircraft. However, not all are close to implementation. Let's look at the most promising ones.
So, Russian aircraft manufacturers who inherited the experience of Soviet masters deserve special attention. As mentioned earlier, today, within the walls of TsAGI named after Zhukovsky, according to its employees, the creation of the concept of a new generation supersonic passenger aircraft has almost been completed.
The official description of the model, provided by the press service of the institute, mentions that it is a “light, administrative” aircraft, “with a low level of sonic boom.” The design is carried out by specialists, employees of this institution.
Also, in a message from the TsAGI press service it is mentioned that thanks to the special layout of the aircraft body and the special nozzle on which the noise suppression system is installed, this model will demonstrate the latest achievements in the technological development of the Russian aircraft industry.
By the way, it is important to mention that among the most promising TsAGI projects, in addition to what has been described, is a new configuration of passenger airliners called the “flying wing”. It implements several particularly relevant improvements. Specifically, it makes it possible to improve aerodynamics, reduce fuel consumption, etc. But for non-supersonic aircraft.
Among other things, this institute has repeatedly presented finished projects that have attracted the attention of aviation enthusiasts from all over the world. Let's say - one of the last, - model supersonic business a jet capable of traveling up to 7,000 kilometers without refueling and reaching a speed of 1.8 thousand km/h. This was presented at the exhibition “Gidroaviasalon-2018”.
“...design is going on all over the world!”
In addition to the Russian ones mentioned above, the following models are also the most promising. American AS2 (capable of speeds up to Mach 1.5). Spanish S-512 (speed limit - Mach 1.6). And also, currently at the design stage in the USA, Boom, from Boom Technologies (well, it will be able to fly at a maximum speed of Mach 2.2).
There is also the X-59, which is being created for NASA by Lockheed Martin. But it will be a flying scientific laboratory, not a passenger plane. And no one has planned to put it into mass production yet.
The plans of Boom Technologies are interesting. Employees of this company say that they will try to reduce the cost of flights on the supersonic airliners created by the company as much as possible. For example, they can give an approximate price for a flight from London to New York. This is about 5000 US dollars.
For comparison, this is how much a ticket costs for a flight from the English capital to “New” York, on a regular or “subsonic” plane, in business class. That is, the price of a flight on an airliner capable of flying at a speed of more than Mach 1.2 will be approximately equal to the cost expensive ticket on a plane that could not make the same fast flight.
However, Boom Technologies bet that it will not be possible to create a “quiet” supersonic passenger airliner in the near future. Therefore, their Boom will fly at the maximum speed it can develop only over water. And when you are above land, switch to a smaller one.
Given that the Boom will be 52 meters long, it will be able to carry up to 45 passengers at a time. According to the plans of the company designing the aircraft, the first flight of this new product should occur in 2025.
What is known today about another promising project - AS2? It will be able to carry significantly fewer people - only eight to twelve people per flight. In this case, the length of the liner will be 51.8 meters.
Over water, it is planned to be able to fly at a speed of Mach 1.4-1.6, and over land - 1.2. By the way, in the latter case, thanks to its special shape, the plane, in principle, will not generate shock waves. For the first time, this model should take to the air in the summer of 2023. In October of the same year, the aircraft will make its first flight across the Atlantic.
This event will be timed to coincide with a memorable date - the twentieth anniversary of the day the Concordes last flew over London.
Moreover, the Spanish S-512 will take to the skies for the first time no later than the end of 2021. And deliveries of this model to customers will begin in 2023. The maximum speed of this aircraft is Mach 1.6. It can accommodate 22 passengers on board. The maximum flight range is 11.5 thousand km.
The client is the head of everything!
As you can see, some companies are trying very hard to complete the design and begin creating aircraft as quickly as possible. For whom are they willing to rush in such a hurry? Let's try to explain.
So, during 2017, for example, the volume of air passenger traffic amounted to four billion people. Moreover, 650 million of them flew long distances, spending from 3.7 to thirteen hours on the way. Next - 72 million out of 650, moreover, they flew first or business class.
It is these 72,000,000 people, on average, that those companies that are engaged in the creation of supersonic passenger aircraft are counting on. The logic is simple - it is possible that many of them will not mind paying a little more for a ticket, provided that the flight will be approximately twice as fast.
But, even despite all the prospects, many experts reasonably believe that the active progress of supersonic aviation, created for the transport of passengers, may begin after 2025.
This opinion is confirmed by the fact that the mentioned “flying” laboratory X-59 will first take to the air only in 2021. Why?
Research and Outlook
The main purpose of its flights, which will take place over several years, will be to collect information. The fact is that this aircraft must fly over various populated areas at supersonic speed. Residents of these settlements have already expressed their consent to conduct tests.
And after the laboratory plane completes its next “experimental flight”, people living in those populated areas, over which it flew, must talk about the “impressions” that they received during the time when the airliner was above their heads. And especially clearly express how the noise was perceived. Did it affect their livelihoods, etc.
The data collected in this way will be transmitted to the Federal Aviation Administration in the United States. And after their detailed analysis by experts, perhaps the ban on supersonic airliner flights over populated land areas will be lifted. But in any case, this will not happen before 2025.
In the meantime, we can watch the creation of these innovative aircraft, which will soon mark the birth of a new era of supersonic passenger aviation with their flights!
Supersonic speed is the speed at which an object moves faster than sound. The flight speed of a supersonic aircraft is measured in Mach - the speed of the aircraft at a certain point in space relative to the speed of sound at the same point. Nowadays it is quite difficult to surprise with such speeds of movement, but just some 80 years ago this was only a dream.
Where it all started
In the forties of the twentieth century, during the Second World War, German designers actively worked on resolving this issue, hoping to use such aircraft to turn the tide of the war. As we know, they didn’t succeed, the war ended. However, in 1945, closer to its completion, the German pilot L. Hoffmann, testing the world's first jet fighter Me-262, was able to reach a speed of about 980 km/h at an altitude of 7200 m.
The first to realize the dream of all pilots to overcome supersonic barrier, became American test pilot Chuck Yeager. In 1947, this pilot was the first in history to overcome the speed of sound in a manned vehicle. He flew the prototype rocket-powered Bell X-1 aircraft. By the way, German scientists and their developments captured during the war greatly contributed to the appearance of this device, as well as, in fact, to the entire further development of flight technologies.
The speed of sound was reached in the Soviet Union on December 26, 1948. It was an experimental aircraft LA-176, at a flight altitude of 9060 m, piloted by I.E. Fedorov and O.V. Sokolovsky. About a month later, on this aircraft, but with a more advanced engine, the speed of sound was not only reached, but also exceeded by 7000 m. The LA-176 project was very promising, but due to tragic death O.V. Sokolovsky, who controlled this apparatus, the developments were closed.
Subsequently, the development of this industry slowed down somewhat, as a significant number of physical difficulties arose associated with controlling an aircraft at supersonic speeds. At high speeds, such a property of air as compressibility begins to manifest itself, and aerodynamic streamlining becomes completely different. Wave resistance appears, and such an unpleasant phenomenon for any pilot as flutter - the plane begins to heat up very much.
Faced with these problems, designers began to look for a radical solution that could overcome the difficulties. This decision turned out to be a complete revision of the design of aircraft intended for supersonic flights. The streamlined shapes of airliners that we now see are the result of many years of scientific research.
Further development
At that time, when the Second World War had just ended and the Korean and Vietnamese wars began, the development of the industry could only occur through military technologies. That is why the first production aircraft capable of flying faster than the speed of sound were the Soviet Mig-19 (NATO Farmer) and the American F-100 Super Saber. The speed record was held by an American aircraft - 1215 km/h (set on October 29, 1953), but already at the end of 1954 the Mig-19 was able to accelerate to 1450 km/h.
Interesting fact. Although the USSR and the United States of America did not conduct official military operations, real repeated combat clashes during the Korean and Vietnam Wars showed the undeniable advantage of Soviet technology. For example, our Mig-19s were much lighter, had engines with better dynamic characteristics and, as a result, a faster rate of climb. The radius of possible combat use of the aircraft was 200 km greater than that of the Mig-19. That is why the Americans really wanted to get their hands on an intact sample and even announced a reward for completing such a task. And it was realized.
After the end of the Korean War, 1 Mig-19 aircraft was hijacked from an air base by Korean Air Force officer No Geum Seok. For which the Americans paid him the required $100,000 as a reward for delivering an undamaged aircraft.
Interesting fact. The first female pilot to reach the speed of sound is American Jacqueline Cochran. She reached speeds of 1,270 km/h while piloting an F-86 Saber aircraft.
Development of civil aviation
In the 60s of the last century, after the appearance of technical developments tested during the wars, aviation began to develop rapidly. Solutions were found for the existing problems of supersonic speeds, and then the creation of the first supersonic passenger aircraft.
The first ever flight of a civilian airliner faster than the speed of sound occurred on August 21, 1961, on a Douglas DC-8. At the time of the flight, there were no passengers on the aircraft other than the pilots, and ballast was placed to accommodate the full load of the aircraft under these experimental conditions. A speed of 1262 km/h was reached while descending from an altitude of 15877 m to 12300 m.
Interesting fact. On February 19, 1985, a China Airlines Boeing 747 SP-09 entered an uncontrollable dive while flying from Taiwan's Taipei to Los Angeles. The reason for this was engine malfunctions and subsequent unqualified actions of personnel. During the dive from an altitude of 12,500 m to 2,900 m, where the crew was able to stabilize the aircraft, the speed of sound was exceeded. At the same time, the airliner, not designed for such overloads, received serious damage to the tail section. However, with all this, only 2 people on board were seriously injured. The plane landed in San Francisco, was repaired and subsequently carried out passenger flights again.
However, truly real supersonic passenger aircraft (SPS), capable of regular flights at speeds above the speed of sound, were designed and built of all two types:
- Soviet airliner Tu-144;
- Anglo-French aircraft Aérospatiale-BAC Concorde.
Only these two aircraft were able to maintain supersonic cruising speed. At that time, they were superior to even most combat aircraft; the design of these airliners was unique for their time. There were only a few types of aircraft capable of supercruise; today, most modern military vehicles are equipped with such capabilities.
Aviation of the USSR
The Soviet Tu-144 was built somewhat earlier than its European counterpart, so it can be considered the world's first supersonic passenger airliner. The appearance of these aircraft, both Tu-144 and Concorde, will not leave any person indifferent even now. It is unlikely that there have been more beautiful aircraft in the history of aircraft manufacturing.
The Tu-144 has attractive characteristics, with the exception of range practical application: higher cruising speed and lower landing speed, higher flight ceiling, but the history of our airliner is much more tragic.
Important! The Tu-144 is not only the first flying, but also the first crashed supersonic passenger airliner. The crash at the Le Bourget air show on June 3, 1973, in which 14 people died, was the first step towards the end of Tu-144 flights. Unambiguous causes have never been established, and the final version of the disaster raises many questions.
The second crash near Yegoryevsk in the Moscow region on May 23, 1978, where a fire occurred during the flight and 2 crew members died during landing, became the final point in the decision to stop operating these aircraft. Despite the fact that after analysis it was established that the fire occurred as a result of a defect in the fuel system of the new engine being tested, and the aircraft itself showed excellent controllability and reliability of the design, when the one on fire was able to land, the aircraft were removed from flights and taken out of commercial operation .
How it turned out abroad
The European Concorde, in turn, flew for much longer, from 1976 to 2003. However, due to unprofitability (the aircraft could not be brought to the minimum payback), the operation was also eventually curtailed. This was largely due to the plane crash in Paris on July 25, 2000: during takeoff from Charles De Gaulle airport, the engine caught fire and the plane crashed to the ground (113 people died, including 4 on the ground), as well as the terrorist attacks of September 11 2001 Despite the fact that this was the only accident of the aircraft in 37 years of operation, and the terrorist attacks were not directly related to Concorde, the general decrease in passenger flow reduced the already lacking profitability of flights and led to the fact that this aircraft made its last flight on route Heathrow - Filton 26 November 2003
Interesting fact. A ticket for a Concorde flight in the 70s cost at least $1,500 one way; towards the end of the nineties, the price rose to $4,000. A ticket for a seat on the last flight of this liner already cost $10,000.
Supersonic aviation at the moment
To date, solutions similar to the Tu-144 and Concorde are not expected. But, if you are the kind of person who doesn’t care about the cost of tickets, there are a number of developments in the field of business flights and small-capacity aircraft.
The most promising development is the XB-1 Baby Boom aircraft from the American company Boom technology from Colorado. It is a small aircraft, about 20 m long and with a wingspan of 5.2 m. It is equipped with 3 engines developed in the fifties for cruise missiles.
The capacity is planned to be about 45 people, with a flight range of 1800 km at a speed of up to Mach 2. At the moment, this is still a development, but the first flight of the prototype is planned for 2018, and the aircraft itself must be certified by 2023. The creators plan to use the development both as a business jet for private transportation and regular flights small capacity. The planned cost for a flight on this car will be about $5,000, which is quite a lot, but comparable to the cost of a business class flight.
However, if you look at the entire civil aviation industry as a whole, then with today’s level of technology development, everything does not look very promising. Large companies are more concerned with profitability and profitability of projects than with new developments in the field of supersonic flight. The reason is that throughout the history of aviation there have not been sufficiently successful implementations of tasks of this kind; no matter how many attempts were made to achieve the goals, they all failed to one degree or another.
In general, those designers who are involved in current projects are rather enthusiasts who are optimistic about the future, who, of course, expect to make a profit, but are quite realistic about the results, and most of projects so far exist only on paper, and analysts are quite skeptical about the possibility of their implementation.
One of the few truly large projects is the Concorde-2 supersonic aircraft patented last year by Airbus. Structurally, it will be an aircraft with three types of engines:
- Turbofan jet engines. Will be installed at the front of the aircraft;
- Hypersonic air-breathing engines. They will be mounted under the wings of the airliner;
- Rocket engines. Installed in the rear fuselage.
This design feature involves the operation of different engines at certain stages of flight (takeoff, landing, movement at cruising speed).
Considering one of the main problems of civil air transportation - noise (standards of the organization air traffic In most countries, they set restrictions on noise levels; if the airport is located close to residential areas, this imposes restrictions on the possibility of night flights), Airbus has developed a special technology for the Concorde-2 project that allows vertical take-off. This will practically avoid shock waves from hitting the surface of the earth, which in turn will ensure no discomfort for people below. Also, thanks to a similar design and technology, the flight of the airliner will take place at an altitude of about 30-35,000 m (at the moment, civil aviation flies at a maximum of 12,000 m), which will help reduce noise not only during take-off, but throughout the entire flight, since At such a height, shock waves will not be able to reach the surface.
The future of supersonic flight
Not everything is as sad as it might seem at first glance. In addition to civil aviation, there is and will always exist the military industry. The combat needs of the state have driven the development of aviation as before and will continue to do so. The armies of all states need more and more advanced aircraft. From year to year this need only increases, which entails the creation of new design and technological solutions.
Sooner or later, development will reach a level where the use of military technologies may become profitable for peaceful purposes.
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Tu-144 became the world's first supersonic passenger airliner. Taking off before the Anglo-French Concorde, it opened a new era in world civil aviation. The creation of the Tu-144 brought the domestic aviation industry to the most advanced positions.
Related industries have also made huge technological leaps. The Tu-144 became, not without reason, a source of pride for the Soviet people.
Successes in the development of combat jet aircraft gave rise to the idea of creating a supersonic passenger airliner. Talk about such an aircraft began to circulate in Europe and America, and in order not to lag behind Western countries, and it is better to get ahead of them, it was decided to begin designing such an aircraft in our country. On July 16, 1963, the resolution of the Central Committee of the CPSU and the Council of Ministers of the USSR No. 798-271 was issued “On the creation of the A.N. Tupolev Design Bureau SPS Tu-144 with four jet engines and on the construction of a batch of such aircraft.” Tupolev's son was appointed the lead designer of the aircraft. The development of the engine was entrusted to the Design Bureau of N.D. Kuznetsov. 
Initially, it was planned to create a passenger version of the Tu-135 missile carrier, the design of which at that time was being developed at the Tupolev Design Bureau. However, after the calculations, the designers came to the conclusion that significant alterations in the design would be required and that an aircraft from scratch would be much more profitable. When working on the project, the developers had to face a number of complex technical problems: aerodynamics, kinetic heating, elastic and thermal deformations of the structure, new lubricants and sealing materials, new life support systems for passengers and crew. The development of the design and aerodynamics of the wing required a lot of effort (200 options were studied in the wind tunnel). The use of titanium alloys in construction required the creation of new machines and welding machines. These problems, together with the A.N. Tupolev Design Bureau, were solved by specialists from TsAGI, CIAM, SibNIA and other organizations. Since 1965, regular consultations have been held with the designers of the French company Aerospatial, which developed the Concorde. During the preparation of working drawings, more than a thousand specialists were seconded from the OKB of O.K. Antonov and S.V. Ilyushin. 
When designing the aircraft, two analogue aircraft of the MiG-21I were used as a working model (now one of them is stored in the Air Force Museum in Monino). The MiG fuselage was shortened by 0.75 m. An ogive-shaped wing was installed on it, which was a smaller copy of the Tu-144 wing. In 1967, an analogue aircraft successfully flew at speeds of 2500 km/m. The test results formed the basis for the final calculation of the wing. Future Tu-144 pilots also trained on the MiG-21I. The MiG-25, Su-9 and Tu-22 were also involved in test flights.
By the summer of 1965, the most important design and layout decisions for the aircraft had been made. In July, A.N. Tupolev presented the preliminary design of the Tu-144 to the MGA. In the same year, a model of an aircraft with a wingspan of about 2 m was exhibited at the Le Bourget air show. On June 22, 1966, a full-size mockup of the aircraft was approved. In parallel with the design, the experimental production of the OKB in Zhukovsky was producing two prototypes (flight and for static tests). The Voronezh and Kuibyshev aircraft factories also participated in their production. Construction of the first prototype was completed on October 9, 1968. On December 31, the crew led by test pilot Yelyan took it into the air for the first time. On June 5, 1969, the prototype reached the speed of sound, and on June 26, 1970, it doubled it. For testing the Tu-144, pilot Yelyan was awarded the title of Hero of the Soviet Union. 
The Tu-144 was first shown at an aviation festival at Sheremetyevo Airport on May 21, 1970. In the summer of 1971, trial operation of the prototype began at Aeroflot. Flights were made from Moscow to Prague, Berlin, Warsaw, Sofia. In 1972, the Tu-144 was demonstrated at air shows in Hanover and Budapest. 
On June 3, 1973, Tu-144 No. 77102 crashed during a demonstration flight at the Le Bourget air show. All six crew members (Hero of the Soviet Union, Honored Test Pilot M.V. Kozlov, Test Pilot V.M. Molchanov, Navigator G.N. Bazhenov, Deputy Chief Designer Engineer Major General V.N. Benderov, Leading Engineer B A. Pervukhin and flight engineer A. I. Dralin) died. The cause of the disaster was a too sharp maneuver that the crew had to make in order to avoid a collision with the unexpectedly appeared French Mirage. Subsequently, the Mirage pilot, who explained that he only wanted to photograph the Tu-144, was acquitted by a French court. However, if we take into account the fact that the Tu-144 was a direct competitor of the Concorde, both the actions of the French pilot and the acquittal of the court give reason to assume that the Tu-144 crash was the result of deliberate actions by the French side. 
Simultaneously with the flight tests, research was carried out at 80 ground stands, where all the most important design and layout solutions were worked out. With the help of these stands, for the first time in the USSR, a comprehensive system for assessing failures taking into account their consequences was developed. State tests continued until May 15, 1977. On October 29, the aircraft received a certificate of airworthiness. 
The Tu-144 is an all-metal low-wing aircraft, made according to the “tailless” design. The fuselage is of a semi-monocoque design with a smooth working skin, reinforced with stringers made of extruded profiles and a set of frames. The aircraft has a tricycle landing gear with a nose strut. Four turbojet bypass engines NK-144A designed by OKB N.D. Kuznetsov (on the Tu-144D - afterburning RD-36-51A designed by OKB-36 by P.A. Kolesov) are located under the wing close to each other. Each engine has a separate air intake. The air intakes are grouped in pairs. The nose landing gear is retracted into the space between the air intake blocks in the front part of the fuselage. The aircraft wing has a variable sweep angle (76° at the root and 57° at the ends of the wing). The wing skin is made of solid aluminum alloy plates. Along the entire trailing edge there are elevons made of titanium alloys. Elevons and rudders are deflected using irreversible boosters. To improve visibility during takeoff and landing, the forward part of the fuselage is made lowering. The main volume of fuel is located in 18 wing tanks. A balancing tank is installed at the rear of the fuselage. Fuel is pumped into it in flight to shift the center of mass during the transition from subsonic to supersonic speed. An onboard computer is used to control the aircraft. The landing approach can be carried out automatically at any time of the day and in any weather. For the first time in the USSR, the Tu-144 used an automatic system for monitoring the technical condition of on-board systems, which makes it possible to reduce the labor intensity of maintenance. 
The first production Tu-144 was assembled in the spring of 1971 in Zhukovsky. In 1972, production began at the Voronezh Aviation Plant. A total of 16 aircraft were built. Another one remained unfinished. The production aircraft differed from the prototype by having a fuselage length increased by 5.7 m, a slightly modified wing shape and the presence of retractable front wings. The number of seats for passengers increased from 120 to 140. The first flight of the production aircraft took place on September 20, 1972 on the route Moscow - Tashkent - Moscow. In March 1975, the Moscow-Alma-Ata high-speed airline opened (carrying mail and cargo), and on October 20, 1977, the first flight with passengers was carried out.
However, the Tu-144 also had enemies. Fearing responsibility, many MGA officials did their best to slow down the process of Aeroflot's development of the aircraft. The accident with the experimental Tu-144D on May 23, 1978 served as a formal pretext for stopping the operation of the Tu-144 with NK-144 engines on passenger lines, although from the very beginning it was clear that this accident occurred precisely because of the design features of the Tu-144D modification. In 1979, a number of cargo flights to Khabarovsk were carried out on Tu-144D aircraft. Later, in 1981-1982, decisions were made to resume passenger transportation, but they remained on paper. 
Until the mid-90s, Tu-144 aircraft were used for various tests, as well as for research into the ozone layer of the Earth’s atmosphere, solar eclipses, focused sonic boom. Cosmonauts undergoing training under the Buran program trained on the Tu-144. In July 1983, the crew of test pilot S.T. Agapov on the Tu-144D set 13 world aviation records that have not been broken to this day. The experience gained during the creation of the Tu-144 was used in the development of heavy supersonic aircraft Tu-22M and Tu-160.
At the request of the Ministry of Science and by decision of the MAP, several aircraft were installed as exhibits on the territory of the Air Force Museum in Monino, the Civil Aviation Museum in Ulyanovsk, and aircraft factories in Voronezh, Kazan and Samara. Some of the aircraft were sold to a private museum of technology in Sinheim (Germany). 
The idea of Russian President Vladimir Putin, inspired by the flight of the new “White Swan”, to create a supersonic aircraft made not only the employees of the Kazan Aircraft Plant, but also many other observers think. Could a missile carrier inspire designers to create new types of supersonic aircraft?
The largest and most powerful supersonic aircraft in the history of military aviation, the Tu-160, known to many by its nickname “White Swan,” recently received a new life. For the first time in many years, the Kazan Aircraft Plant presented to the public the updated Tu-160M bomber, named after the first commander-in-chief of the Russian Air Force, Pyotr Deinekin.
The first flight of the missile carrier was personally observed by the Supreme Commander-in-Chief of the Russian Armed Forces and Russian President Vladimir Putin. The head of state was deeply impressed by the flight of the new “White Swan” and highly appreciated the professionalism of the pilots performing the maneuver, asking them to thank the pilots even before the landing of the aircraft. The president’s emotions were not surprising, since Putin himself piloted the Tu-160 missile carrier back in 2005.
At the end of the flight, the president expressed a proposal to Kazan aircraft designers to create a version of the passenger supersonic “Swan” for civil aviation based on the new Tu-160M.
But in order to understand how realistic it is to realize Vladimir Putin’s idea, you should turn to history Russian aviation and remember what steps have already been taken by aircraft designers in this direction.
Tu-144
One of the greatest industrial successes in Russian history was the creation of the Tu-144 aircraft. It was manufactured long before the Tu-160 and became the first supersonic passenger airliner in the history of mankind. In addition, the Tu-144 to this day is one of two famous history types of supersonic passenger aircraft.
The airliner was created on the instructions of the Council of Ministers of the USSR, issued on July 19, 1963. To the first supersonic passenger plane serious demands were made. The aircraft was supposed to be capable of flying at a cruising speed of 2,300 to 2,700 km/h over a distance of up to 4,500 kilometers, while carrying up to 100 passengers on board.
The first prototype of the aircraft was created by the Tupolev Design Bureau in 1965. Three years later, the plane took to the skies for the first time, two months ahead of its main and only competitor, the famous British-French Concorde.
The Tu-144 had a number of design features that even outwardly distinguished it from other aircraft. There were no flaps or slats on its wings: the plane slowed down thanks to the deflecting nose of the fuselage. In addition, the ancestor of modern GPS navigators was installed on the airliner - the PINO (Projection Indicator of Navigation Situation) system, which projected the necessary coordinates onto the screen from a filmstrip.
However, due to the excessive costs of operating and maintaining the airliner, the Soviet Union abandoned further production of the Tu-144. By the time production was abandoned, a total of 16 aircraft remained, two of which were later destroyed in the infamous crash at the Le Bourget International Air Show in 1973 and in the crash over Yegoryevsk in 1978. At the moment, there are only eight assembled aircraft left in the world, three of which can be fully restored and ready for further use.
SPS-2 and Tu-244
Photo: Stahlkocher / wikimedia.org
Another project that had serious expectations was the SPS-2, which was later given the promising name Tu-244 by its developer, the Tupolev Design Bureau.
The first information about work on a second-generation supersonic passenger airliner dates back to approximately 1971–1973 of the last century.
When developing the Tu-224, the designers took into account both the experience of creating and operating its predecessors - the Tu-144 and Concorde, and the Tu-160, as well as American supersonic aircraft projects.
According to the plans of the SPS-2 developers, the new airliner was supposed to lose the main “ business card» its predecessor - the downward deflecting nose of the fuselage. In addition, the glass area of the cockpit had to be reduced to a minimum sufficient for visibility. It was planned to use an optical-electronic vision system for takeoff and landing of the aircraft.
Also, the designed aircraft was supposed to rise to a height of up to 20 kilometers and accommodate about 300 passengers on board. To achieve such parameters, it was necessary to dramatically increase its size in all respects, which is what was planned to be done: with a fuselage length of almost 90 meters and a wingspan of about 50 meters, the Tu-244 would look like a giant compared to any existing analogues.
But the maximum speed of the airliner, compared to its predecessors, practically remained the same: the speed limit of the SPS-2 did not exceed 2500 km/h. In contrast, it was planned to increase the maximum flight distance to about 9,000 kilometers by reducing fuel consumption.
However, the production of such a supersonic heavyweight in reality modern world turned out to be economically unfeasible. Due to increased requirements for environmental standards, the costs of operating such a Tu-244 aircraft are currently prohibitive both for the aircraft manufacturer itself and for the country’s economy as a whole.
Tu-344 and Tu-444
These aircraft were developed by the Tupolev Design Bureau (later Tupolev OJSC, now Tupolev PJSC) as a response to the growing global demand for fast and small business-class aircraft. This is how various SBS projects - supersonic business aircraft - appeared.
Such aircraft were supposed to be small in size and able to carry about 10 passengers. The first SBS project from Tupolev, the Tu-344, was planned to be produced back in the 90s of the last century on the basis of the military supersonic bomber Tu-22M3. But its development turned out to be a failure in the initial stages, since for international flights the aircraft also had to meet high requirements in the field, which it did not meet already in the first stages of the project’s development. Therefore, the designer refused further work on the creation of the Tu-344.
Work on the project of its successor, the Tu-444, began in the early 2000s, its development reached the stage of the first sketches. Despite the fact that environmental problems had been resolved, the project required the attraction of large financial investments, but Tupolev was unable to find investors interested in this.
S-21 (SSBJ)
Photo: Slangcamm/ wikimedia.org
The only domestic project to create a supersonic aircraft for civil aviation, the development of which was not carried out by the Tupolev Design Bureau, was the project of the S-21 aircraft, also known as the Sukhoi Supersonic Business Jet (SSBJ).
The Sukhoi Design Bureau began work on this project in the 80s. The design bureau understood that the demand for large supersonic airliners had fallen since the days of Concorde and Tu-144 and would only decline in the future for reasons of economy. Therefore, Sukhoi designers were among the first to come up with the idea of creating a supersonic business aircraft designed for direct flights between world capitals.
But the development of the S-21 was hindered by the collapse of the USSR, along with which government funding for the project ceased.
After the collapse of the Soviet Union, Sukhoi tried for many years to attract private investors to the project in Russia and abroad. The volume of incoming investments made it possible to conduct the first tests of engines for the S-21 in 1993.
But to complete the creation and start of serial production of the aircraft, according to the statement of Mikhail Simonov, the head of Sukhoi at that time, about one billion US dollars was required, but new investors for the company could not be found.