Military Review

Experimental aircraft Celera 500L. Secret preparation for a breakthrough

Creation and testing of new technologies in the field aviation can give serious advantages over competitors, and the results of such work should be protected from unauthorized persons. This is exactly the approach that the American company Otto Aviation Group uses in its Celera 500L pilot aircraft project. The car was developed in an atmosphere of secrecy, and test results have not yet been published. This is almost a revolution in air transportation.

Aircraft Celera 500L in 2017. One can see the features of the tail and the direct wingtips. Photo by

Mysterious object

Otto Aviation Group is owned by William Otto, a physicist and former employee of Rockwell International. The company was founded in the last decade, but the general public found out about it only a few years ago in the context of a new promising project.

Roughly at the end of the 2000s, Otto Aviation began to study the appearance of an experimental aircraft designed to search for new technologies. In 2014, a patent appeared for some developments on the topic. This document is still one of the main sources of data on the Celera 500L project. At the same time, since the time of application, the appearance of the aircraft has managed to change markedly.

In April 2017, an unknown characteristic aircraft was spotted at one of the airfields in California. Subsequently, several new photographs appeared, as well as the “found” 2014 patent of the year. Some of the data is on the registry of the US Federal Aviation Administration. All available materials allowed us to present the main goals and objectives of the pilot project. At the same time, the lack of official data seriously complicated any analysis.

The scheme of a full-fledged passenger aircraft (above) and its power set (below). Drawings from US9308989B2

At the beginning of 2019, new photographs of the aircraft appeared. In May, it became known that Celera 500L runs on the runway. This was the reason for the assumption about the imminent start of flight tests. Otto Aviation does not confirm or deny such assumptions, and indeed remains silent.

Special design

According to the patent, the main objective of the project is to obtain the highest possible fuel efficiency that exceeds the similar indicators of any other modern aircraft. A key way to achieve this is to optimize glider aerodynamics. By minimizing air resistance, it is proposed to reduce the required engine power and generally increase efficiency. Estimated fuel consumption is several times less than the same parameter for the most advanced modern aircraft.

It can be assumed that in a characteristic airframe, composites are widely used to reduce the weight of the structure. The patent proposes an original aircraft design with a lightweight power set of a minimum number of longitudinal and transverse elements.

The work of mechanization of the wing. Drawings from US9308989B2

The glider has a characteristic shape and appearance, indicating the optimization of aerodynamics. An experienced aircraft received a streamlined fuselage in the form of an ellipsoid with a narrowing tail. The bow forms the cabin, and the glazing is completely fit into the contours of the skin. In the fuselage placed units of a three-post chassis. The tail compartment is given under the power plant. In newer photographs, the Celera 500L has a pair of air intakes on the roof of the fuselage, previously missing.

A straight wing of large elongation with raised tips is used. The latter appeared during the refinement of the machine and were first noticed only this year. According to the patent, a new type of aircraft should have a wing with a laminar flow. It also provides advanced mechanization in the form of two-section retractable, forming two slots. Drives are provided with full control over the relative position of the wing elements. Apparently, such devices should provide the maximum possible flow control in all flight modes.

The Celera 500L received a large keel and ventral crest, as well as horizontal tail. Instead of individual rudders on the plumage, all-turning planes are used.

Experienced aircraft at the beginning of 2019. Photo by

According to the registry of the Federal Aviation Administration, the aircraft is equipped with one Raikhlin RED A03 diesel engine with power up to 500 hp. The engine is located at the tail of the fuselage and rotates the five-blade propeller. Photo 2017 and 2019 gg. show different screw design. In the current configuration, the screw has a saber-shaped blade with a bend. The patent application described a different aircraft design in which two engines rotate a single pushing screw through a gearbox.

No information is yet available on the instrumentation and electronic equipment of the experimental aircraft. Apparently, he carries a modern complex of flight and navigation aids that meets the requirements of the law. Also on board may be sensors and means of collecting information for testing.

The dimensions and mass of the experimental machine remain unknown. From the published documents it follows that the purpose of the current tests is to collect data necessary for the development of a passenger aircraft of original architecture. Perhaps such a machine will be different from the existing prototype.

Expected Opportunities

According to the patent, an aircraft of the Celera 500L type must show high performance characteristics. The optimal flight mode involves climbing to altitudes of up to 65 thousand feet (more than 19,6 km) and accelerating to speeds of 460-510 miles per hour (740-820 km / h).

Fuselage close-up. Photo by

In this case, fuel consumption will be between 30 and 42 mpg (12,8-17,8 km per liter or 0,08-0,06 liters per 1 km). For comparison, the popular Pilatus PC-12 turboprop cargo passenger aircraft spends 1 gallons of fuel on 5 miles with lower flight data. Turbojet aircraft of the same size and weight, showing a similar speed, also lose in fuel consumption.

An efficient wing with advanced mechanization should provide takeoff and landing at speeds of approx. 90 miles per hour (145 km / h). The estimated stall speed is 112 km / h. The aircraft will need a runway 900 m long.

Secret trials

The existence of the Celera 500L project became known in the spring of 2017, and by this time the development company had time to build and put a prototype at the airport. Apparently, then the work was limited only to ground tests and did not proceed to test flights. At the same time, engineers from Otto Aviation managed to collect certain data and finalize the project.

Airplane while taxiing and jogging. Photo Scott Howe /

At the beginning of 2019, the experimental aircraft was again seen only in the parking lot. Only in May, the car was noticed in motion - it performed high-speed runs in the lane, but made no attempt to rise into the air. It is possible that right now Otto Aviation is preparing its first flight. In addition, it cannot be ruled out that it has already taken place - in a traditional atmosphere of secrecy for the project.

Given the pace of work on Celera 500L, it can be assumed that flight tests will take several years and will go without much haste. In the foreseeable future, it is necessary to raise the aircraft into the air and determine its general flight qualities, as well as to complete the design refinement. Only after that it will be possible to start flying in the required modes and to fully research the main capabilities of the aircraft.

Unknown future

The Celera 500L project is based on a whole series of ideas of various kinds, aimed at improving flight and economic performance. This fact alone makes the project extremely interesting from the point of view of technology and prospects. If an experienced aircraft confirms the declared characteristics, its basic solutions can be widely used. Failure to complete the tests will also be a peculiar result, since it will show the lack of benefit from specific solutions.

Take-off without take-off. Photo Scott Howe /

An extremely interesting and unusual feature of the Celera 500L project is secrecy. The main ideas of this project can affect the development of civil aviation, but Otto Aviation decided to work them out without attracting too much attention. Perhaps this is due to the desire to keep their developments secret, so that they can immediately enter the market with ready-made solutions suitable for implementation. Naturally, on a commercial basis.

Lack of information on all major issues prevents the correct prediction of further events. So far, one can speak with equal confidence both of the great potential of the project and of the potential failure. The actual results will be clear only after the completion of the tests and the publication of their results. Perhaps the experienced Celera 500L will indeed launch a revolution in civil aviation.

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  1. Grandfather
    Grandfather 15 September 2019 05: 23
    something, this "revolutionary cucumber" did not impress ...
    1. lev1759
      lev1759 15 September 2019 17: 27
      And I was impressed ... Immediately Zadornova remembered ....
      1. Tatar 174
        Tatar 174 15 September 2019 18: 43
        Quote: Dead Day
        something, this "revolutionary cucumber" did not impress ...

        And what should it be to impress ???
        1. Tatar 174
          Tatar 174 15 September 2019 18: 45
          Would the Soviet "EKIP" be impressed if it flew?
          1. Hort
            Hort 19 September 2019 10: 21
            Well, the developer’s ekip model seemed to fly ...
  2. Avis-bis
    Avis-bis 15 September 2019 05: 52
    Some sort of cross between the fat Piaggio 180 and Westwind.
  3. mark1
    mark1 15 September 2019 05: 54
    An airplane with a 500-horsepower diesel engine, does not eat fuel from the word "at all", the ceiling is 20 km, the speed is over 800 km / h ... Could this be ?!
    1. MBRSS
      MBRSS 15 September 2019 14: 20
      Complete nonsense. With such wings and a propeller and a 20 km ceiling. And why didn’t they even make the bottom of the fuselage flat? Well, if it rises to 6-8 km.
    2. lev1759
      lev1759 15 September 2019 17: 31
      20 km ceiling, speed for 800 km / h ... Can this be ?!

      Yes, quite ... Make a rubber shell, inflate with helium, run into the center of a typhoon ... The truth will fly in a circle ...
  4. Graz
    Graz 15 September 2019 06: 05
    the design is of course ugly
  5. Mainbeam
    Mainbeam 15 September 2019 06: 16
    Review article, little information.

    It’s scary to trust chains on mechanization.

    Front-side view is not very. But this was to be expected with this form. Looks less ugly from a different angle.

  6. Amateur
    Amateur 15 September 2019 06: 19

    Again Groundhog Day Does VO pay its authors?
  7. Mountain shooter
    Mountain shooter 15 September 2019 06: 32
    There are two types of secrecy. One hides the true nature of a technical solution while it is in development so that competitors do not get stolen. The other one does the same thing so that they don't guess that this development is a "Panama"! Like that company that "a drop of blood complete diagnostics", "Steve Jobs in a skirt" - investors LOST a couple of billions ... From the point of view of conservation laws, a 5-6 times reduction in fuel consumption is unlikely ... Maybe that's why classified?
  8. 3danimal
    3danimal 15 September 2019 06: 44
    This plane reminded me of the shape of the Piaggio Avanti.
  9. cost 75
    cost 75 15 September 2019 07: 12
    Is it that he will eat less fuel than a small car? Is it possible ?
  10. maxxavto
    maxxavto 15 September 2019 08: 13
    Maya in the form of an airplane looks like
  11. KVU-NSVD
    KVU-NSVD 15 September 2019 08: 53
    Large air monopolies will eat these rationalizers, do not go to a fortuneteller. Immediately (after entering the market) and irrevocably. Can, for example, ICE work on water? Answer: maybe .. but it’s unprofitable for the wallet of some cool dudes
    1. Lopatov
      Lopatov 15 September 2019 09: 18
      Quote: KVU-NSVD
      Large air monopolies will eat these rationalizers, do not go to a fortuneteller. Immediately (after entering the market) and irrevocably. Can, for example, ICE work on water? Answer: maybe .. but it’s unprofitable for the wallet of some cool dudes

      Devour if the military does not take under the wing. A military economical aircraft are very interesting. The same for several days a large drone can hang in the air.
      1. KVU-NSVD
        KVU-NSVD 15 September 2019 09: 24
        Quote: Spade
        Devour if the military does not take under the wing

        Do you think that the military does not listen to the opinion of transnational corporations in strategically important things? The same Boeing will eat this company with the full approval of the military
        1. Lopatov
          Lopatov 15 September 2019 10: 03
          Quote: KVU-NSVD
          Do you think that the military do not listen

          Not everything is heeded. Too good option.
          1. KVU-NSVD
            KVU-NSVD 15 September 2019 10: 08
            Quote: Spade
            Not everything is heeded.

            the degree of listening increases according to the results of filling (pah, lobbying) of the wallet.
            1. Lopatov
              Lopatov 15 September 2019 10: 10
              Quote: KVU-NSVD
              the degree of listening increases according to the results of filling

              If this is a breakthrough in profitability, no money will help. Have to negotiate with the developers.
              1. KVU-NSVD
                KVU-NSVD 15 September 2019 10: 17
                Convinced laughing but will there be a breakthrough? Articles in the press and the real cost of exploitation are often not identical and disappointing.
      2. madrobot
        madrobot 15 September 2019 09: 58
        He also first of all thought about a drone that can hang in the air for days, but then he remembered that such fuel economy is achieved only at an altitude of ~ 20 km and a cruising speed of ~ 800 km / h. Why might such a drone be needed? Unless as a relay what. Or ammunition that will guard the next Osama bin Laden. But it will turn out to be remarkably expensive.
        1. Lopatov
          Lopatov 15 September 2019 10: 09
          Quote: madrobot
          Why might such a drone be needed?

          First of all, the sea.
          Plus UAV refueling
          Plus repeater, reconnaissance, RT reconnaissance, AWAC, etc.

          Yes, and as a combatant, carrying out duty in the air will be quite himself. The Iraqis had several Cessna Kombat Caravan "Helfaers" launched by the hundreds. And the Americans have long been using converted Hercules refueling aircraft as a "platform" for these missiles.
          1. madrobot
            madrobot 15 September 2019 10: 17
            I didn’t think about the sea, yes. But it’s excusable for me - since my birth I have been living in Sverdlovsk / Yekaterinburg. Where is Ekb and where is the sea? laughing
            Of all that you have listed, the most relevant seems to be the AWAC.
  12. beeper
    beeper 15 September 2019 09: 54
    The idea of ​​the Celera 500L is interesting, albeit confusing. For example, judging by the scheme of the openwork power set, one cannot do without a "working" thickened skin ?! Indeed, in the rarefied air of high flight altitude, the internal pressure of the "inflated" pressurized passenger cabin will also act on the fuselage. In this regard, the wide cutout of the fuselage under the entrance hatch somehow looks dumb - it is clear that in this case, the picture of the deformations of the fuselage, additionally loaded with internal air pressure, will not be axisymmetric and the large hatch (although its small "wraps" are visible in the photo) the entire perimeter) is a clear "weak link, leading to a possible catastrophic depressurization of the cabin ?!"
    After all, the opening opening is located at an angle to the air flow, in theory, in flight, additionally "pressing" the hatch, but if the hatch is lost, it also acts as a giant air intake for destructive pressure ?! Therefore, the perimeter of the entrance hatch will probably have to be strengthened in the future, and this is an additional weight of the structure and a corresponding decrease in the estimated fuel efficiency ?!

    So doubts about the lack of adjustable stabilizers, then the whole load on balancing a loaded aircraft in the air will additionally fall on all-turning elevators, apparently given to the on-board computer at full disposal ?! It is also unclear the effect of such all-turning rudders on a pushing screw located close to them ?!
    The wing mechanization in the diagram from the patent also looks extreme in the load pattern of the corresponding wing ribs and slit flap suspension elements, which requires constant flight monitoring for cracks and fractures in their critical sections ??!

    The idea of ​​the project developers, in general, is understandable - to create an ideal "aerodynamically clean" aircraft with an optimized (including minimized design loads ???) "dry weight ... but already in the course of experiments with real design, as we can see, “aerodynamically impure” large air intakes of the engine “appeared”, significantly “shading” the pushing propeller downstream, and raised wingtips, instead of theoretically “ideal” elliptical ...
    So the "concept" of Otto Aviation itself is very interesting and looks cobbled together from "ideal examples" of a textbook on aerodynamics, but what will come of this tempting idea in the end - I hope to see more ??! winked
    I thank the respected Author Ryabov Kirill and the editorial board of VO for raising the Interesting Topic and Articles about Celera 500L! good
    1. Rusfaner
      Rusfaner 15 September 2019 16: 07
      So I immediately "rested" on the screw. He will work in a disturbed stream, especially on landing - there will be no efficiency! Where will speed and altitude come from?
      The mysterious American soul ...
      1. beeper
        beeper 15 September 2019 16: 56
        Can the entire airship-like voluminous body fill the helium-breathing mixture ?! smile
    2. NN52
      NN52 15 September 2019 20: 23
      Why is there no porthole on the flying prototype? Has anyone thought about this?
      What, then embed?)))
      But the patent has ...
      1. beeper
        beeper 15 September 2019 20: 50
        Quote: NN52
        Why is there no porthole on the flying prototype? Has anyone thought about this?
        What, then embed?)))

        Why didn't you "think" ?! smile I even compared it with a patent drawing and with an experimental model - there is also, in the row of portholes, and two evacuations on the sides are provided, also a technical requirement for reliable sealing of the hull of such a "high-altitude liner" ?! winked
        I think that this was done on purpose (in the passenger version, the entrance hatch will also most likely be changed and taken from the pilot's cabin to the tail, because the pilots of the serial "passenger" are not provided with an emergency exit from the emergency aircraft with a parachute), since at first, without weakening design and extra costs for the equipment of windows and passenger seats, a "clean" concept of economical flight "aerodynamically ideal (even the wings are located" ideally "for air flow around the middle of the fuselage cross-section)" of the aircraft, and strain gauges without distortion "are being worked out" will draw a picture of deformations of the "bearing skin of the fuselage before the" insertion "of the windows (and it is possible to" insert "them later, at the next stage of testing ?!) ?! winked
        1. NN52
          NN52 15 September 2019 21: 03
          "Static" is done either this way or not ... And they test it either in this configuration or in another ...
          Most likely this office was already crushed by the military ... I don’t see other options ... IMHO.
          1. beeper
            beeper 15 September 2019 21: 19
            Quote: NN52
            "Static" is done either this way or not ... And they test it either in this configuration or in another ...
            Most likely this office was already crushed by the military ... I don’t see other options ... IMHO.

            And this, and don’t go to the grandmother, a potential military intelligence officer and a "tainus agentus" scout, of course, everything is under military control, otherwise where does such a hyper "encryption" of a tiny firm come from ?! smile
    3. Mwg
      Mwg 16 September 2019 16: 26
      And I had a question about take-off and landing. Something low is a plane in itself and a tail ventral keel with a propeller in centimeters from the runway. How will he take off, land then ???
      1. beeper
        beeper 16 September 2019 17: 38
        hi So after all, in order, dear MVG, to protect the propeller blades from touching the runway surface, at the time of takeoff and landing, this large ventral ridge with a shock-absorbed "crutch" lever is arranged (look at the photo, you can see it).
        Of course, in case of a rough landing or takeoff with "blasting", and not smoothly-smoothly, the ventral ridge will hesitate and the propeller will not protect.
    4. Antares
      Antares 19 September 2019 11: 33
      Quote: pishchak
      squeaker September 15, 2019 09:54
      The idea of ​​Celera 500

      nice comment thanks
  13. VadimL
    VadimL 15 September 2019 12: 30
    The idea is understandable, but I personally have doubts about the stability and controllability of this unit.
  14. Pavel57
    Pavel57 15 September 2019 12: 52
    Their breakthrough must be answered by airplanes with a lively fuselage section.
  15. iouris
    iouris 15 September 2019 13: 06
    More and more people keep our secret.
  16. VladVlad
    VladVlad 15 September 2019 14: 12
    Fuel consumption Boeing 737 800 - 2 526 kg / h. It carries 189 people. Per passenger - 13.5 liters per hour !!!
    1. barsuk
      barsuk 16 September 2019 14: 48
      Speed ​​955 km / h, 1,41 liters per 100 kilometers
  17. AAK
    AAK 15 September 2019 14: 18
    Like an experimental machine - it will pull. If you embody something larger for a commercial purpose - there will be completely different engines and other characteristics of efficiency
  18. Basarev
    Basarev 15 September 2019 17: 15
    Interesting idea. I predict that in business transportation an airplane can find a place.
  19. The comment was deleted.
    1. beeper
      beeper 15 September 2019 20: 56
      Class !!! This is aerodynamics, akin to our maple "helicopters" !!! smile Thank you for the cognitive (learn, live and learn!) yes ) video, dear aka Pacifist with AK! good
  20. demo
    demo 15 September 2019 20: 39
    Tupolev Andrey Nikolaevich - aphorisms, quotes, sayings and sayings
    Only beautiful planes fly well.

    And it's all.
  21. eaglet
    eaglet 15 September 2019 21: 12
    In general, it looks very much like an air bomb .... maybe for this they create ...
  22. Pacifist with AK
    Pacifist with AK 15 September 2019 21: 48
    Quote: pishchak
    Class !!! This is aerodynamics, akin to our maple "helicopters" !!! smile Thank you for the cognitive (learn, live and learn!) yes ) video, dear aka Pacifist with AK! good

    Always please, dear)))))))))))) All the best! ......
  23. Undecim
    Undecim 15 September 2019 23: 01
    "... the aircraft is powered by one Raikhlin RED A03 diesel engine with up to 500 hp."
    The same engine is installed on the Yak-152.
    1. Dmitry Kallistov
      Dmitry Kallistov 17 September 2019 13: 35
      That's just the Yak-152 is smaller and lighter than this trough. And its maximum speed is 500 km / h and a ceiling height of 4 km
      1. Undecim
        Undecim 17 September 2019 13: 57
        If you do not drown in the author’s verbiage, but look at the topic yourself, it turns out that the power plant is not exactly known. There is information that it consists of two engines working on one screw.
  24. alien308
    alien308 15 September 2019 23: 27
    With such a virtue as a high load on the wing, there are many worries.
  25. Captain Nemo
    Captain Nemo 16 September 2019 02: 10
    The main secret is the use of an diesel engine with a consumption of 160gr / hp. in hour.
  26. Kruglov
    Kruglov 16 September 2019 04: 49
    Screw on 20 thousand ... And what, for THIS ITEM, will there be special physics ?!
    1. Satanator
      Satanator 16 September 2019 20: 23
      definitely special and physics, and chemistry, given the fact that this screw spins diesel! laughing
  27. rocket757
    rocket757 16 September 2019 08: 28
    Is THIS a personal "pepelats"? Those. will everyone park at their own porch?
  28. swzero
    swzero 16 September 2019 08: 55
    And how is the issue of thickening of diesel fuel at high altitudes being resolved now? I remember ours in the Second World War with this tormented on the Pe-8 and Er-2 with the ACh-30
    1. alien308
      alien308 16 September 2019 17: 18
      Low paraffin, add kerosene.
      1. swzero
        swzero 16 September 2019 19: 11
        And when changing heights, what should I do? Drain kerosene back?
  29. xax
    xax 16 September 2019 13: 19
    500 h.p. ... 0,08-0,06 liters per 1 km ... rise to a height of more than 19,6 km ... 740-820 km / h

    In tow, camping
  30. DDT
    DDT 16 September 2019 15: 18
    Such a cute belly !!! I wish I was like that, fly home, for the weekend ... fellow
  31. DimerVladimer
    DimerVladimer 16 September 2019 16: 54
    I don’t see anything particularly revolutionary. Well, diesel is economical.

    Here is the MIG-8 for 1945 - was unusual

    And an ellipsoidal barrel with a laminar wing and a diesel engine is not a fact.

    I wonder where they will take warm air to heat the wing sock, pressurizing anti-icing protectors ... put heating mats? ... diesel exhaust heat exchanger?
    The fate of the ATR-72 with a laminar wing, regularly breaking from icing, is also memorable ...
  32. srha
    srha 16 September 2019 19: 01
    In June, there was already an article about this barrel with wings. They found out that this is the reincarnation of an unsuccessful idea of ​​the middle of the last century "planet satellite" (see WIKI)
    He didn’t fly at 250 horses even then, and he won’t fly at 03 horses (RED A12 V400 Turbo-diesel Engine). Because the secret ... Or does someone believe in PR omnipotent?
    1. kupitman
      kupitman 18 September 2019 09: 50
      Almighty PR does a great job.
      a simple iphone example - everyone believes that this is an American product, but the fact is that it is made in China, and the Indians write the code for the OS, when you (Americans) call Apple TP, then call not to Delaware, but to India, and if you are in the Russian Federation, then call to Kazakhstan (at best).
      All this PR allows these phones to sell> $ 1000, while it is no better than smartphones at the price of $ 500 - $ 600.
      Therefore, if you make a competent PR, then this device will fly and will be sold.
  33. Whisper
    Whisper 16 September 2019 23: 40
    Ha ha..kabachok!
  34. dgonni
    dgonni 17 September 2019 08: 11
    Given the reduced flight altitude and speed, this sample is simply a mockup and a trial model on which aerodynamics of takeoff and landing should be worked out. For the screw of such heights and speeds will not reach a priori. Plus, a pressurized cabin for pax and crew. In addition, a sealed compartment for transporting all living creatures and jets in the form of what frost and low pressures are not needed.
    P.S. In appearance, a jet engine with a large contour is asked for in the tail, and the shape suggests that it should be two regimes.
    P.S. 2 Once Mig - 11 was with a piston in the tail and the type of reverse sweep of the wing. And then there was 1947. There are pluses, there are also minuses. But this is clearly not a paksovoz!
  35. Dmitry Kallistov
    Dmitry Kallistov 17 September 2019 13: 28
    The optimal flight mode involves climbing to a height of 65 thousand feet (more than 19,6 km) and accelerating to a speed of 460-510 miles per hour (740-820 km / h).

    Have you seen enough fantastic films?
    Already at an altitude of over 5 km, a 500-horsepower diesel engine will lose half its power.
    At altitudes of 5-10 km, the engine should be at least gas turbine.
    I don’t know what kind of aircraft he designed there, but I can notice that this overripe cucumber, with such a layout and such an engine, will be able to reach a speed of only 300-400 km / h
    And its payload is generally zero.
    The plane is a secret ..... so that everyone with a laugh does not take a break.
  36. Antares
    Antares 19 September 2019 11: 40
    humanity is trying, experimenting.
    The experiment itself is not so expensive (compared to some)
    Of course, on the path of evolutionary development, we turned off from supersonic airliners and returned a step back. For cheaper. Let and longer. His Majesty the Consumer here also forces us to go even further - fuel economy. Even cheaper km of track.
    Cheaper ticket = more flights = more tickets = more money
  37. Chetbor
    Chetbor 28 May 2020 21: 57
    "The optimal flight regime provides for ascent to an altitude of 65 thousand feet (more than 19,6 km) and acceleration to a speed of 460-510 miles per hour (740-820 km / h)."
    If this is the true speed, then the frogs at this height the instrument will be less than the stall speed.
    If the instrument - then this is M more than 1 ... on the right wing ...))))