Why do aircraft corporations make identical planes? How to tell the difference between Airbus and Boeing

IL-96. 1994

Denis Okan (pilot-instructor Boeing 737): So is Mr. Boeing and Mademoiselle Airbus so inhumane that for the sake of economy (it is logical to assume that two engines consume less fuel than four) they are ready to sacrifice the lives of their customers by removing “extra” engines from the aircraft?

Really modern aircraft with two engines not enough thrust to perform a go-around?

I'll be brief: no and no

Four engines does not mean a twofold advantage in traction over two. This misconception can only occur to a very outsider for aviation. That is, as the aircraft are different, so the engines can also be different.

But one thing is common in all aircraft - the ability to ensure a safe continuation of takeoff in the event of an engine failure. That is, if one engine fails at , that if one engine fails at , it is possible to continue the takeoff safely. Since we are talking about a go-around, then a safe go-around too, but the go-around itself will be easier to perform, because. it is understood that the aircraft is already lighter (than it was on takeoff), and the speed with altitude has already been gained (handling is better and the margin over obstacles is higher).

In order to achieve the necessary safety performance, pilots must comply with the calculation requirements maximum masses(for takeoff and for landing), which are just the same and are limited to a scenario with one failed engine.

To do this, the pilot must take into account:

• runway length
• takeoff obstacles
• the normalized climb gradient that an aircraft must withstand in any event of an engine failure
• conditions - temperature, wind, pressure.

Now all this is easier to consider than before, because. various specialized (and certified!) programs came to the rescue, which can quickly and accurately calculate the conditions for any lane. Well, before I had to calculate all this according to graphs, nomograms, tables.

I repeat, the need to calculate the maximum takeoff (landing) weight does not depend on the number of engines. That is, if the pilot “scored” on the calculation and decided to “risk” taking off with a mass exceeding the maximum for the given conditions, then with all the engines running, he will, of course, take off ... but if one fails, he will have problems.

Modern engines are very, very powerful. Moreover, for twin-engine aircraft, this power has to be set with a certain margin - just for the reason that if the 1st engine fails, the liner with 2 loses half of the thrust. That is, twin-engine liners can have a greater thrust-to-weight ratio than three- or four-engine ones. Let's say my 2-engine has a similar (even a little more) thrust-to-weight ratio, which has three engines

I would like to make a special note: a Boeing 777 (two engines) is less likely to fall down during a go-around due to a lack of power than an Il-86 of similar capacity (four engines). You can dump, but only intentionally or out of your own stupidity.

In fact, there is some drawback that twin-engine liners have - in the event of an engine failure, a large turning moment appears, which the pilot must parry in time. Again, on B777 / 787 aircraft, airbuses, starting with, there are electronic assistants that reduce this problem to zero. Well, we, pilots, have to demonstrate our skills, which we constantly train (and confirm) on simulators. I wouldn't say it's difficult.

If one engine fails on an aircraft with 4, the turning moment will also be present, but not so pronounced.

Modern engines are very, very reliable. The failure of an engine on a modern aircraft is a very rare event. The vast majority of pilots in their entire career do not experience this failure. Accordingly, the failure of two engines is even less likely, although landing on the Hudson (the defeat of the aircraft by wild geese) showed that this could still happen.

I mean, maybe, but unlikely.

There was another case on the B777, in which both engines stopped and it did not reach the runway (everyone survived thanks to the unique “volatility” of the aircraft and the coordinated actions of the crew and ground services. But in that case there were certain problems with the fuel, which began to freeze during prolonged flying in very low temperatures. A similar situation happened with the Tu-154 in Novosibirsk, which also managed to safely fly to the runway after successively stopping all THREE engines (low-quality fuel).

That is, if there are problems with fuel, then there is no big difference in the number of engines.

Now let's talk about the resumption of history with the IL-96. As I understand it, they are thinking of “modernizing” the plane, and a certain Yuri Sytnik (a well-known person in the past) described his wishes for “modernization” in an article on Mail.ru in this way:

What is IL-96? Yury Sytnik, honored pilot of Russia, member of the presidential commission on the development of general aviation, explains:

“About 10 aircraft flew to Sheremetyevo. They flew for 55 thousand hours, not a single accident, not a single disaster. the car is very good. The fact is that if the engines are now installed differently, so that they eat a little less fuel, and you need to make ladders, as on the IL-86, they were specially produced, the car will be very good. They decided to restore the IL-96 now, because there were many speeches, on my part too, and we wrote a note specifically to the president. I don't know if she got it or not. But all of us old pilots were indignant why such a wonderful aircraft was not produced. The car flies smoothly Far East without landing. From there, it is in the air for 8-10 hours. Carries 300 passengers.

I highlighted the key sentence, after which I only had to smile sadly. If Yury Sytnik is really not aware of his inconsistencies, then, in fact, everything is clear to me why general aviation in the country is in decline.

“The airframe is good, if only the engines were different” - I hear this almost from the very beginning of my career - about the Tu-154, Tu-134, about the Il-86 and now about the Il-96. Like, everything is so simple - I changed the engines, and forward.

But this is a very, very global rework, especially if the aircraft was not originally designed with an eye to the future. By the way, the IL-96, as a continuation of the IL-86, turned out to be something like this - not only the engines were replaced, but also two-thirds of the aircraft. True, even in this form, he did not find demand in the market. People with PGM, of course, will write about the intrigues of capitalism that ruined a competitor to Boeing.

But the second half of the sentence “make ladders, like on the IL-86” - is this a misunderstanding or is Yuri joking? These doors were specially disposed of on the IL-96, because they turned out to be unnecessary on the IL-86, besides, they complicated and made the structure heavier - after all, any opening in the fuselage requires work to increase the strength of this element.

And any weighting of the structure leads ... to an increase in fuel consumption.

The IL-86 was originally intended for mass flights on routes like Moscow - Sochi, so these ladders seemed like a good idea - he walked up to the plane, threw his suitcase and climbed to the second floor. When the plane was placed under a rare at that time air bridge, some problems began with the issuance of suitcases.

However, today there are a lot of airports equipped with air bridges. Make these ladders on modern liner- not the best idea.

I can’t imagine who will need the IL-96 even of the new generation. I can't imagine how much money will need to be pumped into this project to make it truly competitive.

Of course, I really want to see the Russian aviation industry blooming and fragrant, but somehow I don’t believe in the Russian wide-body, especially against the backdrop of still making its way to world fame. Not the time, not the resources, not the heads. Spreading the budget left and right on controversial projects is, in my opinion, a stupid idea.

In aviation, several arrangements of the wing relative to the fuselage (low-wing, center-wing, high-wing) and engines (for example: under the wing, in the tail) are used.

In modern jet passenger liners, the most widespread is the low-wing scheme with engines under the wing. Of course, any layout is a combination of pros and cons, but the advantages of this scheme outweigh its disadvantages. Boeing explored many options and settled on it for their B737, 747, etc. aircraft.

The placement of the engine in the rear part of the fuselage makes it possible to increase the aerodynamic cleanliness of the wing, reduce the noise in the cabin and reduce the aerodynamic effects of jet flow around the fuselage. There is also less destabilizing moment in case of engine failure.

But with that comes its own problems. So, a few words about the layout "Engine in the tail"

"Mine" wrote:
1. There is such a dirty trick in the engines on the tail - the aircraft gets into the so-called protracted, “closed” stall when the aircraft reaches supercritical angles of attack of 25-30 ° and higher. The plane, as it were, "locked" in this position with its nose up, lost speed, fell into a tailspin. Exit to supercritical angles happened when the aircraft hit a powerful updraft, a gust of air. Such powerful impulses high altitudes very rare, but every aircraft, as a rule, gets into them. However, as it turned out, only aircraft with engines on the rear fuselage were unstable in this mode. At supercritical angles of attack, a wake of air breaks off the wing, which falls on the air intake engines (which leads to surge) and on the horizontal tail (elevators), making it ineffective.
Sad example:

And the horizontal plumage of the layout of the engines on the tail, as you know, is located at the top of the keel (if it was installed on the fuselage, it would fall into the gas jet from the engine nozzle). The so-called T-tail is also heavier than usual. Significant weighting of the structure is a significant disadvantage of aircraft with engines on the tail. In addition to the heavy tail unit, the fuselage has the largest weight, on which the power plant that loads it is mounted. As it turned out, on aircraft with engines on the tail, the advantages of the “aerodynamically clean” wing were reduced due to an increase in aerodynamic drag due to the mutual influence (interference) of the engine nacelles and the rear fuselage.

2. In addition, the location of the engines in the tail - they take away part of the cabin, thereby increasing the overall length of the fuselage. Compare the length of a 5-row SSJ (29.94 m, 98 passengers in 19.5 rows) and a 6-row Tu-334 (31.26 m, 102 passengers in 17 rows).

3. There is also a disadvantage associated with the proximity of the engines to each other (as well as the compactness of the fuel lines in the tail): in the event of a fire in one engine, the chances that the fire will affect the second (third) engine (or the fuel supply to them) are many higher than aircraft with widely spaced engines (under the wing).

4. If the engine is suspended under the wing, then its weight is partially balanced by the lift of the wing (in flight). And if it is in the tail, the weight is not balanced by anything, except for the strength of the fuselage and (wings too) construction. Or, to put it differently, the engines on the wings unload well the wing itself - the lifting force tends to lift the wing up.

5. Engines "under the wing" are MUCH more convenient to maintain. From an interview with Jacques Declos: I would like to emphasize that the low position of the engine is a huge advantage for maintenance. Thanks to this location, we are able to replace any equipment within 20 minutes, it will take less than two hours to replace the engine. And the cost of maintenance is one of the most important criteria for a customer airline.

6. Another drawback is associated with a large difference in the centering of the aircraft. Rear-mounted engines cause the aircraft's center of gravity (CG) to shift back. The wing also moves back. As a result, the fuselage and the passenger cabin are divided by the wing into unequal parts - a long nose and a short tail. At the same time, the presence of a commercial load (passengers, baggage, cargo) moves the CG forward relative to the wing, and its absence (ferry variant, incomplete loading) leads to the movement of the aircraft CG back. As a result, the distance between extreme provisions The CG has exceeded all previously known limits in aircraft with a "high engine". How to solve this problem? The first creators of such aircraft - the designers of the Caravels and Il-62 - decided to go the usual way. Let the true run-up be huge, but the aircraft should fly only with its moderate value, which is typical for previous aircraft with engines on the wing, therefore, it is necessary to arrange the wing and main landing gear relative to the forward position of the CG (full load). What will happen when the passengers leave and the DH moves back? Will the plane roll over on its tail? To avoid this, an additional tail landing gear was used on the IL-62, on which the empty aircraft rests. Somehow, during the tests, Vladimir Kokkinaki forgot to remove the tailwheel before takeoff and broke it during takeoff. He commented on this incident as follows: "Everything that the plane does not need flies off." Pilots do not like incomprehensible complications ... At the Caravelle, the role of the tail support was played by an onboard passenger ladder in the rear fuselage (after disembarking passengers, the aircraft rests on it until the tanker fills the wing tanks with fuel). This is on the ground, but how to fly if the CG moves back and the plane turns out to be unstable in flight? The IL-62 has a ballast tank in the forward fuselage, into which water is poured in the absence of a commercial load. After all, fuel should not be placed in the fuselage next to the passenger cabin - this is a fire hazard. Ballast is loaded into the nose trunks on the Caravelle during a ferry flight. This is, if I may say so, a solution to the problem “in French”. It is associated with operational difficulties, dangers of making mistakes when using ballast. In cruising flight, the aircraft flies with small centering differences, which requires less balancing loads on the horizontal tail and its smaller dimensions.

Airplane on its tail

7. So, engines "under the wing" work for the stability of the aircraft and for its good weight culture (ceteris paribus, such an aircraft weighs less than those with engines located differently), i.e. the plane carries more comm. load.

Probably, the above restrictions did not suit the British creators of the VC-10, DH-121, BAC 111. They wanted to solve the problem radically - to ensure the possibility of flight with all the huge centering differences available. In this case, it is necessary to arrange the wing and main landing gear relative to the rear position of the CG (aircraft without load). In this case, the aircraft will never roll over on its tail and will always be stable in flight. But the problem arises when the aircraft is fully loaded. It consists in the fact that the huge shoulder of the main landing gear relative to the CG makes it difficult to detach the front landing gear during takeoff. It is also difficult to balance an aircraft in flight: great efforts are required on the horizontal tail unit and its deflection angles, which increases the resistance in flight. These problems are solved only by a significant increase in the area (and mass) of the horizontal tail. For example, let's compare similarly sized aircraft: the French-style Il-62 has a horizontal tail area of ​​14.7% of the wing area, and the English-style VC-10 has 23%.

Possible engine layouts for passenger liner today, in fact, there are only two - on the tail and under the wing (the upper wing has even more glitches). Naturally, choosing between the mythical danger of “sucking garbage from the strip into the engine” and the hemorrhoids well-known to aviators ...

About the engines on the tail, one can also say what is known about one catastrophe and two "incidents" related to the ice crust from the wings getting into the engines on takeoff. Blame, of course, the airfield service - but the fact remains. “Under the wing” this cannot happen in principle.

And also tell us about the disadvantages of the “engine under the wing” layout

1. The engine under the wing spoils the aerodynamics somewhat
2. The engine under the wing makes noise at cabin level
3. The engine under the wing makes it necessary to make high landing gear, which means that the aircraft needs a gangway for disembarking and boarding passengers, plus a large landing gear is extra weight.

Conclusions on points:

1. The engine spoils aerodynamics EVERYWHERE. Well, except to put it in the fuselage itself. But this is unacceptable because he, the bastard, makes noise, takes up space, in the event of a breakdown, he can start a fire or a meat grinder. And on the pylon - you can look at the fire and go to emergency landing or just discard. ( they drop, really)
2. The taste is tolerable. And in the case of "engine under the wing" - the wing itself shields the noise of the motor.
3. As the size of the aircraft grows, the value of this factor is lost. If in a business class airplane there is simply nowhere to put the engines under the wing, there is a maximum height from the wing to the concrete block, then on the IL-96 it’s like this, like that - you still can’t jump out of the cabin.

Accordingly, the choice of the designer dances precisely on the size of the aircraft. In the middle class - or a built-in gangway and crap with a central heating, or engines under the wing - but it turns out the door is at a high height.

Here's what I found. Admire how people are perverted, just not to put the engine on its tail!!!

Valery Popov wrote: ... Aircraft with engines placed in the tail have another problem - non-localized destruction of the engine. The probability of damage by engine fragments to communications, generators, hydraulic pumps, control system elements is much higher than when engines are placed under the wing. It is possible to certify an aircraft in such a scheme, but the level of safety will be obviously lower than for alternative. The same applies to an engine fire (read Ershov). Moreover, this is a non-localized destruction, in contrast to the ingress of foreign objects into the engine, real danger. Over the past 3-4 years, there have been 2 cases in Russia - Yak-42 and Tu-154. While I don’t remember any problems with foreign objects hitting ...

Drozdov Vadim writes: I will add that on the Tu-154, the most common now, they also tried to solve the problem by tilting back the main landing gear (the axis of the cart is shifted back relative to the rear spar). But they got an additional problem in the form of the need to strengthen the rear of the fuselage due to the appearance of the "scissors" effect when touching the ground. If you look at the fuselage behind the wing, you can see serious reinforcing linings. Nevertheless, it was not possible to completely get rid of the problem and the landing overload was limited to 2.0. This is a rather small value, and the situation is aggravated by the inert behavior of the machine in longitudinal canal, especially with forward alignments. Therefore, the requirements for the piloting technique of this aircraft are very high, and the price of a hard landing is quite high.

Lucas wrote: the engine under the wing - unloads the wing. Those. in terms of weight with the scheme, the engine in the tail loses twice: both the wing is heavier, and the tail begins to weigh like a cast-iron bridge.

exotic: The difference in the fuel system is close to fundamental. Consumable tanks / compartments are located at the "engine along the wing" also in the tanks or next to them. And, if necessary, fuel can be supplied from there even if the aircraft booster pumps fail. When the engines are located on the rear fuselage, this is very difficult.

When the engines are located under the wing, the engines continue to work even with the incredible failure of all SPN. If you assume the failure of all SPNs is probable (for example, the entire electrical system has died), then even in this case the power plant will continue to work. What can not be said about the layout of the "engine in the tail".

06/20/2015 Vetrogonov writes:

16:59 tomashomecat writes:
Is a clean wing and less spacing (torque) of engines an empty phrase for you?

Completely empty. They do not compensate for the large number of shortcomings of butt motors.

06/21/2015 tomashomecat writes:

06/20/2015 Vetrogonov writes:
This is understandable to anyone who is able to imagine the passage of forces in flight along the frame.

1. as far as I know main reason the general transfer of engines under the wing in the 60s was the weight of the then engines of the required power, now there is no such problem.
1. From the point of view of geometry, the center of thrust of the "butt motor" almost ideally coincides with the center of frontal aerodynamic resistance, which facilitates the work of the frame, which cannot be said at all about the engines under the wing of a low-wing aircraft. their pitch-up moment must also be somehow compensated by the fuselage design plus a partial loss of wing efficiency.
2. "butt motor" should not create any problems for the frame design of a modern passenger plane with a powerful deck in the middle of the fuselage.

Kitty, you better not go into the history of aviation! ;)
In the 60s, there was just a mass "mixing" of engines into the tail - following the example of the Caravelle. Even Boeing, after the B-707, created the 727th according to this scheme. And the main factor was the reduction of noise in the passenger compartment.

06/21/2015 asp writes:

09:51 aosta63 writes:
the main reason for moving engines under the wing is the mass of emerging pluses. The wing is unloaded from the existing lift force, and its mass becomes lower. tail section the fuselage also becomes lighter, since it does not have to take up thrust. Access to engines is easier.
and I also vaguely remember that the engine under the wing plays the role of a kind of anti-flutter load
the engine inlet is not affected by disturbances from the wing and it is not obscured. all this contributes to the stability of the engines.

... and they also work as a spare landing gear for engine nacelles, and after traveling on them, the aircraft can be used again :-)

06/21/2015 To an outsider V writes:

The advantages of the "engine under the wing" layout include the fact that with an increase in thrust, an additional pitching moment arises - in contrast to the "engines in the tail" layout, where in the same situation, on the contrary, a diving moment is created.
I remember Tunoshna...
It is clear that not because of this, but maybe it was precisely this smallness that was not enough ... (

06/21/2015 B_A_K writes:

tomashomecat,
As I see it, you are a real know-it-all in aviation :) And where do they only make such people?

The “plus” of the “engines in the tail” scheme can be attributed, by and large, only the “clean wing” and less noise in the front of the cabin. In all other respects, this scheme loses the traditional completely!

The work of the power circuit of the fuselage (and not the frame!) in tension-compression is far from the most important thing. I would say insignificant. The main loading of the fuselage is bending. The diagram of the bending moments acting on the fuselage is determined by the separation of the masses. The more powerful a certain unit (engine, for example) and the farther it is located from the point of application of aerodynamic forces from the wing (1/4 MAR), the more
bending moment, the more metal you put in there. Placing engines in the tail leads to a noticeable shift in the center of gravity of the structure. As a result, the shoulder of the horizontal and vertical tail. It is unlikely that you know that in the horizontal steady flight of a statically stable aircraft, the stabilizer creates negative lift. This is necessary to parry the moment created by a pair of forces: the weight of the aircraft and the lift. Since the stabilizer arm has decreased, the force on the stabilizer has to be increased, which, accordingly, affects the performance characteristics of the aircraft as a whole.
As was rightly noted above by one of the authors, the forward thrust engines, when mounted on the wing, serve as anti-flutter weights. Together with unloading the wing, this allows us to use thinner profiles, which, as we were taught at the institutes, reduces aerodynamic drag (with all the ensuing consequences).
There are still a lot of nuances, for example, an increase in the weight of the fuel system, a greater laboriousness of maintenance and, do not believe it, the engines in the tail are more likely to collect any bad things from the runway. So there is less ambition in judgments, there are reasons that they don’t write about in “Murzilki”, and only the aircraft developer, putting the horseradish to his nose, determines what he can sacrifice and what not, so that his aircraft was bought.

06/21/2015 Engineer_2010 writes:

Krendel V.M. writes: ... the flutter problem is not exhausted by the problem of a plate of infinite span on a torsion spring))

This is accurate, if we take into account that to all the torsional-waving vibrations of the OCHK consoles, an exciting factor from the transverse-vertical vibrations of the engine nacelles is also added. By the way, in the video about SSJ frequency tests, you can clearly see how the engines start to “move” at certain frequencies: http://www.youtube.com/watch?v=mIUUncpPnyM
I heard from the flutter specialists from TsAGI that at one time, both on the Il-86 (or 96, I don’t remember exactly), and on the Tu-204, I had to work hard to solve the problems of wing-engine nacelle interaction. According to their own stories, the Chinese comrades deliberately chose for their "trial balloon" in the face of the ARJ-21 a layout with engines in the HCF, so as not to get involved with this difficult task.
p.s. Shots with "shaking" engine nacelles for about 5 minutes 45 seconds.

On this topic:
If we consider the location of the engines from a historical point of view, then the French were the first to think of putting them in the tail on their Carvelle. By the way, Aeroflot almost bought such planes, but it turned out somehow undignified (the country that created the Tu-104 buys planes from the bourgeois!), and the French did not burn out. But (according to the stories of many representatives of the Tupolev Design Bureau), Khrushchev, having swept on this liner, was simply amazed by the silence in the cabin. And upon arrival home, he slammed his fist on the table - learn, lazy people! This is how the Tu-124A appeared, later called the Tu-134 ...
In general, the tendency to put the engine at the root of the wing was deservedly recognized as wrong, and after the first generation (Kometa, Tu-104 and Tu-124) they did not return to it. The Americans went their own way (motors on a pylon), which turned out to be historically correct and correct in every way. The mentioned E-152 (by the way, not entirely German. It was made on the basis of the experimental bomber "150", built with the active participation of German aircraft designers in the USSR after their return to their historical homeland) is not entirely indicative, because it was high-wing, which greatly simplified the engine suspension on a pylon (they did not scrape the ground). But there would be almost no sound insulation, IMHO. (Those who flew the Il-76 next to the porthole located opposite the engine will understand).
The French, after the ingenious Carvella, sat in a puddle until the very Renaissance under the flag of Airbus, who followed the Murlyukan path, which was recognized as true. In the USSR and England, they continued to sculpt motors in the tail, in packs of 3 - 4 pieces (and let the whole world rest. One is not a decree for us!) VC-10, Trident, Tu-154, Il-62 ... And we have design bureaus Tupolev was never able to realize all the delights of this layout, continuing to spoil the wing with the chassis fairing - well, it’s more familiar to us like that!
The English aircraft industry could not survive the stagnation in the brain (the market economy, you know. Well, local politicians helped). Now they have a production of components, including awesome motors, but no aircraft manufacturing.
But it's not so simple for us. Aircraft of the "fashionable scheme" appeared - Il-86 and 96 (76 does not count, it was not built for that), Tu-204. We flounder a little bit, maybe we'll swim out.
There were also curious exceptions. So the Murlyukans used a "combined" scheme - one motor in the tail, 2 on the pylons. But despite a number of advantages, such aircraft are no longer built. And the German experimenters went farthest of all. On the VFW-Fokker VFW-614, they installed 2 turbojet engines on pylons above the wing! The pylons were slanted back, so the problem of noise was not so urgent. And this device would fly thousands across the sky, if it weren’t for the awful economy. Only a few have been built. Now the Japanese are wiser with that scheme on some business jet. In general, business jets are a special topic, I am not particularly strong in it. But there such arrangements can be found, mother do not cry!
And in addition, about the beak on the wing of the IL-62. I heard this story from the flight engineer. They are decreasing, which means they are bridged onto the strip. And in front of them is a dullard. The Tupolev has more powerful mechanization, the speed on the glide path is lower. And the dispatcher Ilu prompts: slow down, slow down. And the FAC obscene: coco, on ... slow down, from mechanization, I only washed down on the wing!
In general, Ily, IMHO, is better than carcasses. In every way.

Tu-135 aircraft with four NK-6 or NK-135 engines with deflecting wing panels One of the final designs of the Tu-135, based on the basic design with deflecting wing panels of the V-70 type.

Tu-135 with four NK-6 engines and two-keel vertical tail

Aircraft "135" 4VD-19R2

Third group

This group was worked out as a safety net in case of failure in the development of the NK-6 engine and in in general terms, with the exception of power plant, repeated decisions on basic version Tu-135.

Tu-135 aircraft with four engines

VD-19R2 The engines were placed in pairs in packages under the wing.

Basic data of the project Wingspan, m 28.70

fuselage length, m 44.00

aircraft parking height, m ​​11.00 wing area, sq.m 300

wing aspect ratio 2.78

takeoff weight, kg

normal 123000

reloading 145000

practical flight range at a speed of 2850 km/h, km normal variant 6100-6300 reloading variant 7100-7300 flight altitude

over the target, m 21000-21500

takeoff run, m normal version 1800

overload option 2800

Tu-135 aircraft with six "117-165" or R15BF-300 engines

The engines were placed three in two packages under the wing.

Project master data

wingspan, m 34.80

fuselage length, m 50.70 aircraft parking height, m ​​10.70

wing area, sq.m -

wing extension 2.78 take-off weight, kg

normal 175000

reloading capacity 230000 suspended

fuel tanks, kg 20600 cruising speed flight, km/h

on supersonic 2650

at subsonic 920 practical flight range at a speed of 2650 km / h, km

normal version 7100

overload version 9100

at a speed of 920 km / h, km 5000

technical flight range at a speed of 2650 km / h, km normal variant 7600

reloading variant 9600 at a speed of 920 km/h, km 5300 flight altitude above the target, m 23500 takeoff run, m normal variant 1800-2000 reloading variant (with boosters) 2500-3000

Airplane "135" 6"117-165"

Aircraft "135" 4 R15B-300

Aircraft "135" 6R15B-300

Tu-135 aircraft with four R-15B-300 engines (option 2a)

Two engines were placed in one package above the rear fuselage under the keel, two - one under the wing.

Basic data of the project wing span, m 28.80

fuselage length, m 43.00

aircraft length, m 48.30

aircraft parking height, m ​​12.60 wing area, sq.m 300

wing aspect ratio 2.78

takeoff weight, kg

normal 124000

reloading 146000

external fuel tanks capacity, kg 20600

cruising speed, km/h 2650

practical flight range at a speed of 2650 km/h, km normal variant 6300-6500 reloading variant 7300-7500 flight altitude

over the target, m 21200-21700

takeoff run, m

normal version 1750

reloading option 2700

Tu-135 aircraft with six R15B-300 engines

The engines were placed in three packages in pairs - one package above the tail section of the fuselage under the keel, two - under the wing.

Basic data of the project wing span, m 32.80

fuselage length, m 49.50

aircraft length, m 52.60

aircraft parking height, m ​​13.00 wing area, sq. m 417

wing aspect ratio 2.75

takeoff weight, kg

normal 175000

reloading 205000

external fuel tanks capacity, kg 27000

cruising speed, km/h 2650

practical flight range at a speed of 2650 km/h, km normal variant 7400-7600 reloading variant 8500-8700 flight altitude

over the target, m 21400-21600

takeoff run, m normal version 1600-1800 reloading version 2300-2500

Tu-135 with NK-6 or NK-135 engines with deflecting wing panels

Model of one of the variants of the Tu-135 aircraft

Tu-135K aircraft model

As can be seen from the considered projects, at that time the "duck" scheme with a "floating PGO" became the leader in the Design Bureau, which had a number of advantages for supersonic heavy aircraft compared to the normal pattern. The "tailless" scheme, although it was considered as promising, was not found in practical development and application for the "135" project either in TsAGI or in the Design Bureau at that stage due to the insufficiently studied this scheme in the USSR. Subsequently, in the course of large-scale research on Tu-144, this scheme took its rightful place in our heavy supersonic aircraft construction and was used for its projects further development Tu-244 on the SPS-2 theme, as well as in the first projects on the Tu-160 theme and the first Myasishchev projects on the M-18 / M-20 theme.

To be continued

V. V. ROSTOPCHIN

The crew of the SB-2 is preparing for a training flight. Winter 1940-1941

The recognition of mistakes is that powerful factor that makes it possible to correct one's actions in the right (i.e., correct) direction. This is a kind Feedback making the process of state governance sustainable.

1. The origins of the problems

Kok is known / mechanical transfer of experience civil war, political purges and the destruction of the military elite in 1937-1938, led to a strong drop in the combat potential of the Red Army. The subsequent forced restoration of the combat potential of the Red Army and aviation, including, as you know, was poorly supported by material resources and did not give a positive result. For example, if in 1937 the Armed Forces had 18 aviation schools, then on May 1, 1941, there were already 100 of them (“Military personnel on the eve of the war.” Doctor of History, Professor F.B. Komal. Military History Journal No. 2, 1990). But on January 1, 1941, the schools and colleges of the Air Force were only 44.1% full of teachers. In addition, in these educational institutions, instead of 1276 SB aircraft in the state as of September 1, 1940, there were only 535, and F-1 cabins with dual control, instead of the supposed 743 - 217. They were also poorly provided with fuel (41.4% of the need ), the terms of training often changed (from 1939 to 1940 - 7 times) and the number of flight hours.

Appointments and transfers in 1939 alone involved 246,626 people in the service cycle, which at that time accounted for 68.8% of the staff of the commanding staff. During this period, huge movements of officers took place in the army, there were especially many promotions to the positions of senior and senior commanding staff in 1938-1939. This is explained, firstly, by the fact that at that time new regiments, divisions, corps, armies and military educational establishments. Secondly, as a result of the dismissal a large number officers in 1937-1938. there was an additional shortfall in personnel. The voids were filled with new people, many of whom were immediately promoted to major leadership positions, although most of of them did not have the necessary knowledge and experience. And the fact that in these conditions the doctrine of offensive military operations was adopted under any conditions in the event of aggression from the outside was evidence of the illiteracy of the leadership of the state and blatant irresponsibility. As it turned out very soon, already during the Finnish War, not a single branch of the armed forces was ready to conduct not only offensive, but even defensive hostilities.