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    Su-57 Stealth Fighter: News #8

    Mir
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    Post  Mir Tue Jan 16, 2024 7:19 am

    @PeregrineFalcon

    I completely forgot to mention that the two questions I posted were "quasi questions". They just resemble questions - they are not real questions, so there was no need to respond.

    Now I see you have wasted a lot of time writing a complete essay! - I'm really sorry. My bad. Embarassed

    Thanks for the effort anyway thumbsup

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    Stealthflanker
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    Post  Stealthflanker Tue Jan 16, 2024 2:38 pm

    Regarding TVC topics tho.. Feels that it's the Saturn's lobby was stronger compared to Salyut. as Saturn build the most of the AL-31F family including the AL-31FP used by Su-30SM, MKI, MKM and MKA. Klimov and Salyut tho apparently consider Saturn's approach of having the entire exhaust nozzle assembly moving to be inexpedient.

    This is example of Salyut's nozzle.

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    PeregrineFalcon


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    Post  PeregrineFalcon Tue Jan 16, 2024 6:55 pm

    GarryB wrote:
    Here is translated patent paper for the PAK FA:

    Interesting that the all moving vertical tail surfaces seem to be aligned to the angle of cant on the vectored thrust engines... I suspect this is not an accident and makes flight control surface deflection calculations easier or should I say simpler.

    That is not the case, all moving vertical tails are aligned with all other side surfaces of the plane for RCS reduction, and cant angle of the nozzle is calculated to provide the best compromise between pitch and roll/yaw authority.

    GarryB wrote:
    The deflections of the physical control surfaces during a flat spin mean nothing because in a flat spin they wont be capable of providing a useful consistent force to get the aircraft out of the spin as those control surfaces require a smooth clean airflow over them for their deflection to create a force on the cg and axis of the aircraft.... all the control surfaces could be neutral or deployed to their limits, but in a flat spin they wont effect the aircrafts movement through the air because it is spinning and not "flying". It would be like pressing the brake pedal or applying the hand brake on a car in the middle of a jump into the air.

    This is absolutely incorrect, and that is also the reason I wasted so much time explaining to "Mir" how canted 2D TVC nozzles are able to provide precise, controllable nose pointing capability even though they don't have the capability to point the exhaust plume in every direction like true 3D TVC nozzles!

    Aerodynamic control surface are more than capable of providing necessary force to counter unwanted TVC motions in the case of the canted 2D TVC, or to assist the 3D TVC in the post stall region.

    Just to give you example here is the testing of Differential Canard deflection for generation of yawing moment on the X-31 with and without the vertical tail:

    https://ntrs.nasa.gov/api/citations/19960012279/downloads/19960012279.pdf

    "The feasibility of augmenting the available yaw control power on the X-31 through differential deflection of the canard surfaces was studied as well as the possibility of using differential canard control to stabilize the X-31 with its vertical tail removed. Wind-tunnel tests and the results of departure criteria and linear analysis showed the destabilizing effect of the reduction of the vertical tail on the X-31. Wind-tunnel testing also showed that differential canard deflection was capable of generating yawing moments of roughly the same magnitude as the thrust vectoring vanes currently in place on the X-31 in the post-stall regime. Analysis showed that the X-31 has sufficient aileron roll control power that with the addition of differential canard as a yaw controller, the wind-axis roll accelerations will remain limited by yaw control authority. It was demonstrated, however, that pitch authority may actually limit the maximum roll rate which can be sustained. A drop model flight test demonstrated that coordinated, wind axis rolls could be performed with roll rates as high as 50 deg/sec (full scale equivalent) at 50 deg angle of attack. Another drop model test was conducted to assess the effect of vertical tail reduction, and an analysis of using differential canard deflection to stabilize the tailless X-31 was performed. The results of six-degree-of-freedom, non-linear simulation tests were correlated with the drop model flights. Simulation studies then showed that the tailless X-31 could be controlled at angles of attack at or above 20 deg using differential canard as the only yaw controller."

    If the small X-31 canards that are placed very close to each other can generate roughly the same force/torque as TVC, just imagine what for example the differential LEVCON deflection can do, which are far bigger and spaced much further providing much stronger moment arm!
    Also, take a look at the F-22 for example. Differential horizontal tail deflection is more than enough to induce the yaw motion and to control the side slip during flat spin, while the TVC is controlling the pitch axis. All those aerodynamic surfaces are interacting with the clean airflow at post stall AoA, unlike rudders for example, that are in the airframe "shadow".
    The most extreme example is the old Su-35 with canards. That plane was able to do almost every post stall maneuver, including flat spin without TVC!

    GarryB wrote:

    The Russians have been very clever and have been able to use 2D TVC to get all the benefits of 3D TVC flight but with the weight and cost savings of 2D TVC engines.

    They are clever buggers and have once again managed to get superior flight performance at massively reduced costs and prices.

    Call it quasi 3D or 2.5D or just 3D.... who cares anymore.

    That is true, but assuming incorrectly how they have managed to do that would be wrong Wink


    Last edited by PeregrineFalcon on Tue Jan 16, 2024 7:17 pm; edited 1 time in total

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    Post  PeregrineFalcon Tue Jan 16, 2024 7:16 pm

    Mir wrote:@PeregrineFalcon

    I completely forgot to mention that the two questions I posted were "quasi questions". They just resemble questions - they are not real questions, so there was no need to respond.

    Now I see you have wasted a lot of time writing a complete essay! - I'm really sorry. My bad. Embarassed

    Thanks for the effort anyway thumbsup

    I'm sorry you feel this way, because if you think I have wasted a lot of time explaining, it means that you haven't learn nothing, and that is the real shame!
    You have denied yourself from expending your knowledge, and you have put your ego above anything else!

    And I'm sorry if I was little bit rude, but you did waste a lot of my time Wink

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    sepheronx
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    Post  sepheronx Tue Jan 16, 2024 9:00 pm

    Haven't learn nothing is a double negative. You are saying he learned something.

    What is your bitchfest all about again?
    GarryB
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    Post  GarryB Wed Jan 17, 2024 6:50 am


    That is not the case, all moving vertical tails are aligned with all other side surfaces of the plane for RCS reduction, and cant angle of the nozzle is calculated to provide the best compromise between pitch and roll/yaw authority.

    I am suggesting the tail surfaces were aligned with the angle the engines are canted to make the flight control inputs and outputs work better, I understand the tail surfaces are angled for RCS purposes and that the engines are angled to achieve a quasi 3D TVC effect, but do you think it is an accident that both angles are the same... considering the same angling of airflow over the tail surfaces generates similar forces to the ability to angle the thrust of the engines with the same angle of inclination? If careful coordination of the engine nozzles at that angle can allow roll and yaw and bank forces, then the movement of the vertical tails essentially turning perpendicular to that axis should help with control (the engine nozzles go up and down and the tail surface turns left and right on the same axis).


    Aerodynamic control surface are more than capable of providing necessary force to counter unwanted TVC motions in the case of the canted 2D TVC, or to assist the 3D TVC in the post stall region.

    So control surfaces can manouver the aircraft in super stalls at different flight speeds so why bother wasting time with TVC if a canard can fix everything?

    Wind-tunnel testing also showed that differential canard deflection was capable of generating yawing moments of roughly the same magnitude as the thrust vectoring vanes currently in place on the X-31 in the post-stall regime.

    But I would argue it was capable of generating moments in normal flight and not in a superstall or at zero flight speeds or situations where there was no airflow over the canards that they could utilise to generate a lifting force.

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    Post  ALAMO Wed Jan 17, 2024 8:36 am

    sepheronx wrote:Haven't learn nothing is a double negative. You are saying he learned something.

    What is your bitchfest all about again?

    They are competing in a classical DMC Laughing

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    Post  PeregrineFalcon Wed Jan 17, 2024 1:12 pm

    GarryB wrote:

    That is not the case, all moving vertical tails are aligned with all other side surfaces of the plane for RCS reduction, and cant angle of the nozzle is calculated to provide the best compromise between pitch and roll/yaw authority.

    I am suggesting the tail surfaces were aligned with the angle the engines are canted to make the flight control inputs and outputs work better, I understand the  tail surfaces are angled for RCS purposes and that the engines are angled to achieve a quasi 3D TVC effect, but do you think it is an accident that both angles are the same... considering the same angling of airflow over the tail surfaces generates similar forces to the ability to angle the thrust of the engines with the same angle of inclination? If careful coordination of the engine nozzles at that angle can allow roll and yaw and bank forces, then the movement of the vertical tails essentially turning perpendicular to that axis should help with control (the engine nozzles go up and down and the tail surface turns left and right on the same axis).


    Su-57 canted angle of the nozzle is basically the same as the one on the Su-35S, and that plane has purely vertical tails, so I don't see any intentional correlation between canted angle of the nozzle and angle of the Su-57 rudder.
    Angle of the rudder is calculated based on the RCS demands, and as it happens it has very similar inclination as the nozzle which is based on the best compromise between pitch and roll/yaw authority.
    There is almost zero probability that they would alter the rudder angle just to complement the nozzle in some way, because that would change the whole shape of the airframe if you want to keep the planform alignment, and vice versa, there is absolutely no need to have the less optimal canted angle of the nozzle just to complement the angle of the rudder.

    GarryB wrote:


    Aerodynamic control surface are more than capable of providing necessary force to counter unwanted TVC motions in the case of the canted 2D TVC, or to assist the 3D TVC in the post stall region.

    So control surfaces can manouver the aircraft in super stalls at different flight speeds so why bother wasting time with TVC if a canard can fix everything?

    Canards can't fix everything, and this is only a clear example how aerodynamic surfaces are capable of generating yawing moments of roughly the same magnitude as the thrust vectoring.
    It is extremely important where the canards, or some other control surfaces are placed in order to provide the most optimal control at post stall region.
    The planes such as Rafale, EF2000, J-10, JAS 39 Gripen etc. can't exploit post stall region in their current configuration without TVC, and are susceptible to uncontrolled spin if the conventional AoA limits are crossed.
    On the other hand, planes like the old Su-35, Su-30SM and Su-57 can effectively exploit the post stall region without TVC. Even the F-35 is capable of that to some degree.

    Bottom line, aerodynamic control surfaces are powerful toll for controlling, and assisting TVC during post stall maneuvering.

    Quote:

    "Differential deflection of the canard surfaces was shown to produce significant
    levels of yawing moment on the X-31 configuration, particularly at angles of attack above
    40 degrees. Although thrust vectoring provides superior levels of yawing moment below
    40 degrees angle of attack, the addition of differential canard deflection could effectively
    provide augmentation or redundancy in yaw controls for this configuration throughout the
    angle-of-attack range. In fact, it was shown that the combination of both rudder and
    differential canard deflections may provide yaw control power with levels similar to those
    available through thrust vectoring over the entire angle-of-attack range from 0 deg to 80
    deg. If used in conjunction with the existing thrust vectoring on the X-31, differential
    canard may be able to double the available yawing moment at high angles of attack."

    This is exactly what I was trying to explain on the last two pages!
    Aerodynamic control surfaces in conjunction with the TVC can provide far superior controlability and rotational forces/rates than any of them independently can.
    In the case of the 3D TVC, aerodynamic control surfaces are almost purely supplementing the TVC, and in the case of the canted 2D TVC they are also countering unwanted motions.

    That is for example the reason Su-57 can achieve superior post stall characteristics than conventional planes have with pure 3D TVC. Just look at the level of complexity that is going on with the aerodynamic control surfaces and TVC during high AoA velocity vector rolls:



    GarryB wrote:

    Wind-tunnel testing also showed that differential canard deflection was capable of generating yawing moments of roughly the same magnitude as the thrust vectoring vanes currently in place on the X-31 in the post-stall regime.

    But I would argue it was capable of generating moments in normal flight and not in a superstall or at zero flight speeds or situations where there was no airflow over the canards that they could utilise to generate a lifting force.


    As can be see from the previous quote, it was shown that the combination of both rudder and differential canard deflections may provide yaw control power with levels similar to those available through thrust vectoring over the entire angle-of-attack range from 0 deg to 80deg.
    Of course, at zero, or near zero speed there would be no benefit coming from the aerodynamic control surfaces, but that is the region where you have no combat utility. All combat post stall maneuvers are done at certain speed, and at some instances, aerodynamic control surfaces don't need to create lifting force at all to be able to control the motion of the plane. In some cases you just need to create the torque to be able to initiate rotation.
    Mir
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    Post  Mir Wed Jan 17, 2024 6:14 pm

    @PeregrineFalcon

    Not so much an ego problem. The problem is when someone tells you that you have "misquoted" him, when you've used the "quote" button to do so, then you know for sure that that someone is either a politician, or has made an early escape from the asylum. No difference either way as you know for sure it's a good time to quit the conversation.
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    Post  GarryB Thu Jan 18, 2024 3:01 am

    Su-57 canted angle of the nozzle is basically the same as the one on the Su-35S, and that plane has purely vertical tails, so I don't see any intentional correlation between canted angle of the nozzle and angle of the Su-57 rudder.

    The Su-27 as vertical tail surfaces, they didn't change much aerodynamically from that aircraft when making the Su-35 because the Su-27 already pretty much got it right.

    The Su-57 they were focused on manouver performance first and radar cross section second... they said as much themselves... would it not be impossible if they found that the angles were going to be rather similar and there was leeway of a few degrees that they might make them the same because the angle on the vertical tail surface is going to effect its moment effect on the aircraft just like the deflection angle of the engine nozzle is also going to have a moment effect on the aircraft, but the tail surface is left and right and the engine is up and down so a combination of the two angled engines allows a range of flight manouvers to be performed but in normal flight where the rudders have an effect then that adds directly the side the side moment that the engines lacked being 2D only.

    Obviously that only works in normal forward flight when the vertical rudders can exert moment, so why not have the engines vertical and the tail vertical and get the same 3D thrust vectoring effect... well as you point out and I mentioned... the stealth considerations of large vertical tail surfaces.

    Angling the tail surfaces together with the engines gives the same improved performance at normal flight speeds while minimising RCS from the side.

    Obviously when the aircraft is flying sideways the effect of the engines is going to be normal and the effect of the vertical tail surfaces is going to be reduced or eliminated, but the only way to get that effect all the time is the heavier more expensive more complicated 3D nozzles... which would probably allow the elimination of the vertical tail surfaces... which is likely going to be standard on 6th gen fighters as the removal of vertical tail surfaces means less weight and less drag and less RCS, but is going to need 3D TVC engines... and two of them...

    There is almost zero probability that they would alter the rudder angle just to complement the nozzle in some way, because that would change the whole shape of the airframe if you want to keep the planform alignment, and vice versa, there is absolutely no need to have the less optimal canted angle of the nozzle just to complement the angle of the rudder.

    They said several times that manouver performance is given a higher priority than stealth on this aircraft...

    I don't know that I am right and I don't know that you are wrong, but I am not understanding why you are so sure you are right and I am wrong.

    You seem very confident...

    Bottom line, aerodynamic control surfaces are powerful toll for controlling, and assisting TVC during post stall maneuvering.

    Quote:

    "Differential deflection of the canard surfaces was shown to produce significant
    levels of yawing moment on the X-31 configuration, particularly at angles of attack above
    40 degrees. Although thrust vectoring provides superior levels of yawing moment below
    40 degrees angle of attack, the addition of differential canard deflection could effectively
    provide augmentation or redundancy in yaw controls for this configuration throughout the
    angle-of-attack range. In fact, it was shown that the combination of both rudder and
    differential canard deflections may provide yaw control power with levels similar to those
    available through thrust vectoring over the entire angle-of-attack range from 0 deg to 80
    deg. If used in conjunction with the existing thrust vectoring on the X-31, differential
    canard may be able to double the available yawing moment at high angles of attack."

    This is exactly what I was trying to explain on the last two pages!
    Aerodynamic control surfaces in conjunction with the TVC can provide far superior controlability and rotational forces/rates than any of them independently can.
    In the case of the 3D TVC, aerodynamic control surfaces are almost purely supplementing the TVC, and in the case of the canted 2D TVC they are also countering unwanted motions.

    DUDE... you are explaining that canard control surfaces can be as good as TVC based on the experience and findings with a single engined aircraft that uses external paddles to deflect the engine exhaust.... of course its ability to roll is not going to be great with a single engine using paddles to deflect its engine exhaust...

    I would think widely spaced engines in the Su-35 or MiG-29OVT or Su-57 is going to have rather good roll control below 40 degrees and above 40 degrees AoA...

    Of course, at zero, or near zero speed there would be no benefit coming from the aerodynamic control surfaces, but that is the region where you have no combat utility.

    What about a combat situation where an enemy target is detected behind the aircraft so the pilot whips the nose up and over so it is now pointing backwards... radar pointing at the target missile launched... while flying backwards at maybe 400km/h and then pilot pulls back on the stick and orients the nose in the direction of travel and continues onwards at reduced speed but accelerating back up to cruise speed?

    The aerodynamics of the aircraft look great in airshows, but in combat it is about pointing your nose and therefore your main sensors at the target and launching a missile and then continuing on with what it was doing.

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    Post  PeregrineFalcon Thu Jan 18, 2024 4:40 pm

    GarryB wrote:
    Su-57 canted angle of the nozzle is basically the same as the one on the Su-35S, and that plane has purely vertical tails, so I don't see any intentional correlation between canted angle of the nozzle and angle of the Su-57 rudder.

    The Su-27 as vertical tail surfaces, they didn't change much aerodynamically from that aircraft when making the Su-35 because the Su-27 already pretty much got it right.

    The Su-57 they were focused on manouver performance first and radar cross section second... they said as much themselves... would it not be impossible if they found that the angles were going to be rather similar and there was leeway of a few degrees that they might make them the same because the angle on the vertical tail surface is going to effect its moment effect on the aircraft just like the deflection angle of the engine nozzle is also going to have a moment effect on the aircraft, but the tail surface is left and right and the engine is up and down so a combination of the two angled engines allows a range of flight manouvers to be performed but in normal flight where the rudders have an effect then that adds directly the side the side moment that the engines lacked being 2D only.

    The reason I have gave the Su-35S as an example lies in the fact that they have calculated the canted angle of the nozzles based on the most optimal thrust vectoring performance in pitch, roll and yaw in relation to the center of gravity of the plane, and that has absolutely no correlation with the angle of the vertical tail.
    Both planes, Su-35S and Su-57 have basically identical nozzle arrangement irrespectively of the angle of the vertical tails. That should tell you something?!

    Anyway, Su-57 canted angle of the nozzle is not the same as the angle of the rudder:

    Su-57 Stealth Fighter: News #8 - Page 39 Patent10

    How do you explain that?

    GarryB wrote:

    There is almost zero probability that they would alter the rudder angle just to complement the nozzle in some way, because that would change the whole shape of the airframe if you want to keep the planform alignment, and vice versa, there is absolutely no need to have the less optimal canted angle of the nozzle just to complement the angle of the rudder.

    They said several times that manouver performance is given a higher priority than stealth on this aircraft...

    I don't know that I am right and I don't know that you are wrong, but I am not understanding why you are so sure you are right and I am wrong.

    You seem very confident...

    First, I'm confident because I have pretty extensive knowledge on the subject, and more than decade ago I have explained on our local forums in detail how this type of TVC in conjunction with aerodynamic controls and FCS is working. After that I have shared that information on the Key Publishing forum and since then the information was spreading all over the net, even before any official explanation was given.
    Second, everything you have said doesn't make any sense from the mechanical/aerodynamic point of view, and third, we have official info given in the form of the PAK FA patent that is basically confirming everything I have wrote years back, and what I'm saying now!

    https://findpatent.ru/patent/244/2440916.html

    https://findpatent.ru/patent/250/2502643.html

    Quote:

    "The aerodynamic configuration of such an aircraft is subject to the requirements of maximizing aerodynamic quality (increasing lift and reducing drag) at sub- and supersonic flight speeds, and ensuring controllability at ultra-low flight speeds. The external shape of the airframe is subject to requirements to reduce radar signature. All of the above requirements are contradictory, and the creation of an aircraft that meets such requirements represents a certain compromise.
    The inclination of the sides of the fuselage 1 in the cross section, the inclination of the vertical aerodynamic surfaces (vertical tail 4, side edges 8 of the airframe) to one direction in the cross section makes it possible to reduce the ESR in the side hemisphere (BHS) due to the re-reflection of the EM wave incident on the inclined surface of the airframe, in side different from the direction of the irradiating radar.
    The shape of the theoretical contours and the layout of the airframe made it possible to reduce the energy of reflected EM waves in individual angles due to the redistribution of the maxima of the backscattering diagram into the minimum number of directions and into the least dangerous sectors."

    So, it is more than obvious that the angles used for the planform alignment are calculated based on the radar scattering that is going into the least dangerous sectors, and has absolutely nothing to do with the canted angle of the nozzle.

    GarryB wrote:

    DUDE... you are explaining that canard control surfaces can be as good as TVC based on the experience and findings with a single engined aircraft that uses external paddles to deflect the engine exhaust.... of course its ability to roll is not going to be great with a single engine using paddles to deflect its engine exhaust...

    I would think widely spaced engines in the Su-35 or MiG-29OVT or Su-57 is going to have rather good roll control below 40 degrees and above 40 degrees AoA...

    Calling me "DUDE", or Mir calling what I was writhing "BS" doesn't make both of you any less illiterate on the subject. And this is not an insult, it is a fact, and as soon as you accept that, you will start to expend your knowledge!

    Let's take a look what you have claimed:

    "The deflections of the physical control surfaces during a flat spin mean nothing because in a flat spin they wont be capable of providing a useful consistent force to get the aircraft out of the spin as those control surfaces require a smooth clean airflow over them for their deflection to create a force on the cg and axis of the aircraft.... all the control surfaces could be neutral or deployed to their limits, but in a flat spin they wont effect the aircrafts movement through the air because it is spinning and not "flying". It would be like pressing the brake pedal or applying the hand brake on a car in the middle of a jump into the air."

    This is basically pure and utter nonsense!

    Based on the composition of the aerodynamic controls on the Su-57 screen shot I have posed, it is more than obvious that they are actively contributing to the overall control of the plane during post stall maneuvering. I have also presented the screen shot of the Mig-29OVT that has entirely different deflection of the aerodynamic control surfaces since it is using pure 3D TVC, and since that was not enough for you, I have used X-31 official study paper that is brutally disproving your delusional assumptions.
    The fact that they are explicitly talking about yawing motions, and not about rolling (which you are now suggesting), only tells me about your dishonesty, and your attempt to divert the discussion in direction that would be somewhat less painful for you.
    But even if we go with the flow, X-31 using external paddles is providing superior yaw rates than for example J-10B with genuine 3D TVC. And even then the differential canard deflection in conjuction with the rudder is providing almost the same force in the range of angles going from 0 to 80 deg!

    But since that is also not enough for you, let us take a look at the Su-57 patent data!

    Quote:

    "The rotating part 8 of the influx 2 of the fuselage 1, when deflected downward, reduces the area of ​​the planned projection of the fuselage 1 in front of the center of mass of the aircraft, which contributes to the creation of an excess moment for a dive when flying at angles of attack close to 90 degrees. Thus, in the event of a failure of the control system of the jet nozzles 14, it is possible to switch from the flight mode at supercritical angles of attack to flight at low angles of attack without using aircraft control by deflecting the thrust vector of the engines. At the same time, the rotating part 8 of the influx 2 is the mechanization of the leading edge of the influx 2 of the fuselage 1. When the rotating part 8 of the influx 2 is deflected downward in cruising flight mode, it performs a function similar to the function of the rotary sock 9 of the wing."

    Here they are talking about LEVCON's, and it is obvious that they alone provide controlability in the range of angles going to almost 90 deg! This is another official info that is brutally disproving your false statements! And that is not the end, let us go further!

    Quote:

    "The location of the engines in insulated engine nacelles 6 allows a compartment for large cargo to be placed between them. To counteract the turning moment when one of the engines fails, their axes are oriented at an acute angle to the plane of symmetry of the aircraft so that the thrust vector of the operating engine passes closer to the center of mass of the aircraft. This arrangement of the engines, together with the use of rotary jet nozzles 14, the rotation of which is carried out in planes inclined at an acute angle to the plane of symmetry of the aircraft, makes it possible to control the aircraft using the thrust vector of the engines - in the longitudinal, transverse and track channels. Control in the longitudinal channel is carried out with in-phase deflection of the rotary jet nozzles 14, which create a pitching moment relative to the center of mass of the aircraft. The aircraft is controlled in the side channel by means of differential deflection of the jet nozzles 14, which simultaneously create a roll moment and a yaw moment, while the roll moment is countered by the deflection of the aerodynamic controls (10 ailerons and 11 flapperons). Control of the aircraft in the transverse channel is carried out with differential deflection of the rotary jet nozzles 14, creating a roll moment relative to the center of mass of the aircraft."

    So, it is more than obvious that the orientation of the engines and nozzles is purely influenced by the most optimal angles for the rotation of the plane around its center of gravity using TVC (nozzle orientation has nothing to do with the rudder inclination), and it is painfully obvious that the planes FCS is using aerodynamic controls that are quite capable of countering unwanted roll motions.

    And this is precisely what I was talking for the last two pages! If that is not enough official info, than you two have some serious issues!



    And here is the video that might be useful for better understanding how things work.
    At 34:15 F-22 pilot is explaining dynamics of the flat spin, and how aerodynamic control surfaces are inducing and controlling the yaw motions at the deep stall conditions even though the Raptor has 2D TVC that is deflecting only in the pitch plane.
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    Su-57 Stealth Fighter: News #8 - Page 39 Empty Re: Su-57 Stealth Fighter: News #8

    Post  GarryB Thu Jan 18, 2024 11:49 pm

    Anyway, Su-57 canted angle of the nozzle is not the same as the angle of the rudder:

    The vertical tail surfaces on the MiG-29 are not perfectly vertical either.... does that mean they don't work?

    Do you think a rudder turn might throw the entire aircraft out of control because it is a few degrees off vertical?


    First, I'm confident because I have pretty extensive knowledge on the subject, and more than decade ago I have explained on our local forums in detail how this type of TVC in conjunction with aerodynamic controls and FCS is working. After that I have shared that information on the Key Publishing forum and since then the information was spreading all over the net, even before any official explanation was given.
    Second, everything you have said doesn't make any sense from the mechanical/aerodynamic point of view, and third, we have official info given in the form of the PAK FA patent that is basically confirming everything I have wrote years back, and what I'm saying now!

    Yeah, giving an opinion on the internet is one thing but to really say I am wrong you have to understand what I said first, and all I said was that the angling of the engine cant and the angling of the vertical tails is similar and that might assist in making the flight control system easier to design and manage and operate.

    Did you design that flight control system or know someone who did?

    If you didn't and don't then you are free to have your opinion on the subject.

    "The aerodynamic configuration of such an aircraft is subject to the requirements of maximizing aerodynamic quality (increasing lift and reducing drag) at sub- and supersonic flight speeds, and ensuring controllability at ultra-low flight speeds. The external shape of the airframe is subject to requirements to reduce radar signature. All of the above requirements are contradictory, and the creation of an aircraft that meets such requirements represents a certain compromise.

    Is is often the case when quoting you leave something out that doesn't support your case in a discussion... you make bold sections hoping that the other parts are not considered but I would say it was that last sentence you should have made bold... all the requirements are contradictory and the creation of an aircraft that meets such requirements represents a certain compromise. In other words quite a few angles of vertical tail surface would reduce RCS from the side, but this particular angle that they chose might offer the best aerodynamic and control performance as well as reduce RCS... which is all I was saying.

    You act like I am claiming it is the angled tail surface that allows 3D TVC flight to be achieved... in which case saying the Su-35 has vertical tails would be a sensible thing to say... but I didn't... that was all in your head.


    So, it is more than obvious that the angles used for the planform alignment are calculated based on the radar scattering that is going into the least dangerous sectors, and has absolutely nothing to do with the canted angle of the nozzle.

    You can't say that just from that piece of text. The next paragraph about the aerodynamics might mention the bonus to the angles chosen for the vertical tail and the engine alignment allowed improved manouverability because their axis of moment was aligned greatly simplifying the control inputs to both control mediums in the flight control system which is rather more complicated in the Su-35 because the tails are vertical and not all moving like the angled all moving surfaces on the Su-57.



    Calling me "DUDE", or Mir calling what I was writhing "BS" doesn't make both of you any less illiterate on the subject. And this is not an insult, it is a fact, and as soon as you accept that, you will start to expend your knowledge!

    I thought DUDE was more appropriate than WTF Ngger... but you have judged us both illiterate, yet you continue to post pseudo facts and videos of American pilots... the contradiction there is a fact, your opinion of our understanding of anything is not a fact in any sense... it is an opinion.

    if we expend our knowledge we will end up with nothing left, perhaps you could expand your mind and realise this is an internet forum and not a lecture theatre at a university or design department for an aircraft making company in Russia.

    But even if we go with the flow, X-31 using external paddles is providing superior yaw rates than for example J-10B with genuine 3D TVC. And even then the differential canard deflection in conjuction with the rudder is providing almost the same force in the range of angles going from 0 to 80 deg!

    Are we not going to discuss how the X-31 with a single engine that fakes TVC with external paddles generates less roll control than the canards fitted to its nose?

    I mean I fully understand how the differential use of nose mounted canards would would create roll control forces, but how exactly does a single engine with three paddles achieve that?

    The aircraft is controlled in the side channel by means of differential deflection of the jet nozzles 14, which simultaneously create a roll moment and a yaw moment, while the roll moment is countered by the deflection of the aerodynamic controls (10 ailerons and 11 flapperons). Control of the aircraft in the transverse channel is carried out with differential deflection of the rotary jet nozzles 14, creating a roll moment relative to the center of mass of the aircraft."

    {sarcasm}So you are continuing to try to tell us that the 2D vectored thrust engines can contribute yaw and bank and roll effects if the engine is canted... thanks for that... that is new... we never thought that before {/sarcasm}

    Loosing an engine in flight is only a problem on takeoff or in a stall and even then the aircraft should be able to recover unless it is doing a low altitude low speed high angle of attack flight at an airshow. Twin engined aircraft that don't have TVC can still fly on one engine... they can use their conventional control surfaces to compensate for the shifted line of thrust.

    So, it is more than obvious that the orientation of the engines and nozzles is purely influenced by the most optimal angles for the rotation of the plane around its center of gravity using TVC (nozzle orientation has nothing to do with the rudder inclination), and it is painfully obvious that the planes FCS is using aerodynamic controls that are quite capable of countering unwanted roll motions.

    So what you are saying is that the angle chosen for the engine cant is optimised for flight manouvers.

    {super sarcasm}But that I am totally wrong that the vertical tail might have been designed with the same criteria and interests in manouverability... it is just there to bat away radar signals... otherwise they would have no vertical tail at all because obviously the only purpose for a vertical all moving tail surface is to redirect enemy radar so they can't find you. {/super sarcasm}

    And this is precisely what I was talking for the last two pages! If that is not enough official info, than you two have some serious issues!

    Don't you find it interesting that before you started posting on this thread Mir and I were disagreeing, but now we are both unable to read or write (illiterate) and know nothing on the subject you appear to have invented and have been discussing since the internet started.

    At 34:15 F-22 pilot i

    Not really interested in what the youth of America have to say on the subject. This is not an insult... it is just a fact.
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    Su-57 Stealth Fighter: News #8 - Page 39 Empty Re: Su-57 Stealth Fighter: News #8

    Post  thegopnik Sat Jan 20, 2024 4:03 pm

    Stealth is all applied at the front, bottom, sides but never the top side other than the cockpit being treated with some stealth. The Su-57 has a higher flight ceiling then the F-35 and probably can operate at higher normal heights then the F-35. Any face to face engagement would result in the F-35 getting a radar reflection of the Su-57 front and bottom side while the radar reflection the Su-57 would get of the F-35 is front and top side, maybe the 2nd stage engine they could get like a slight bump higher in elevation. It won't even matter if the F-35 had its radars replaced with GaN for a slight bump in detection capabilities.

    Supposedly the F-22 can match the height and maybe range depending how many fuel tanks it will carry. but its avionics are stuck in 2007 and multiple upgrades have been done with the Su-57 and its entire body is a giant EW suppression tool.

    NGAD is the only solution for the Su-57.

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    Su-57 Stealth Fighter: News #8 - Page 39 Empty Re: Su-57 Stealth Fighter: News #8

    Post  GarryB Sun Jan 21, 2024 3:48 am

    There are fundamental problems with the F-35... what are the chances they will get their new Gonad right?

    The F-22 was designed to defeat 4th gen fighters by flying high and fast and shooting missiles from a distance where they are difficult to detect or invisible, but that shit does not work when the enemy has an IADS that is going to detect you and vector interceptors and SAMs to your position... the F-22 can easily detect enemy fighters scanning with radar trying to find them, but interceptors vectored to their position using IRST to locate them and IR guided missiles to shoot them down while they are super cruising around would be a serious problem for them.

    The introduction of wing mounted radar on the Flankers means the Russian 4+ gen fighters have better anti stealth detection capacity than American 5th gen fighters...

    So of course panic... no point in trying to fix them because they will spend trillions trying to fix their problems and upgrading them to the point where they might be useful but odds are they are not going to be superior to the Russian aircraft now let alone the ones they will have in 10 years time, so they are instead going to try to jump a generation... which is always problematic because you don't get the experience of the missed generation and if you can't get 5th gen right how can you expect to do better with 6th gen which is going to be even harder to get right.

    The US does not need a new fighter, it needs an integrated air defence network including SAMs etc that is compatible with their allies... and that will never get off the ground because the Armies run those and they armies are not interested in air defence.

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    Isos
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    Post  Isos Sun Jan 21, 2024 9:38 am

    IMO the main reason they didn't upgrade f22 was price not self confidence.

    It is already very expensive to have and operate. The upgrade would skyrocket the price.

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    Su-57 Stealth Fighter: News #8 - Page 39 Empty Re: Su-57 Stealth Fighter: News #8

    Post  PeregrineFalcon Sun Jan 21, 2024 11:39 pm

    GarryB wrote:
    Anyway, Su-57 canted angle of the nozzle is not the same as the angle of the rudder:

    The vertical tail surfaces on the MiG-29 are not perfectly vertical either.... does that mean they don't work?

    Do you think a rudder turn might throw the entire aircraft out of control because it is a few degrees off vertical?

    I think you just had a brain fart, because everything you have just said has nothing to do with the fact that the Su-57 canted angle of the nozzle is not the same as the angle of the rudder, which is exactly what you have claimed over and over again, and exactly what you have based your unfounded theory on!

    Here is what you have said on multiple occasions:

    GarryB wrote:
    I am suggesting the tail surfaces were aligned with the angle the engines are canted to make the flight control inputs and outputs work better, I understand the  tail surfaces are angled for RCS purposes and that the engines are angled to achieve a quasi 3D TVC effect, but do you think it is an accident that both angles are the same... considering the same angling of airflow over the tail surfaces generates similar forces to the ability to angle the thrust of the engines with the same angle of inclination?

    GarryB wrote:
    ... would it not be impossible if they found that the angles were going to be rather similar and there was leeway of a few degrees that they might make them the same ...

    ...Angling the tail surfaces together with the engines gives the same improved performance at normal flight speeds while minimising RCS from the side.

    In reality the canted angle of the nozzle and angle of the rudder are not the same. It is simple as that, no additional comments are needed, thanks!

    GarryB wrote:
    Yeah, giving an opinion on the internet is one thing but to really say I am wrong you have to understand what I said first, and all I said was that the angling of the engine cant and the angling of the vertical tails is similar and that might assist in making the flight control system easier to design and manage and operate.

    Did you design that flight control system or know someone who did?

    If you didn't and don't then you are free to have your opinion on the subject.

    I am familiar with the most control laws applied to the planes with the TVC, and the fact that I have more than decade ago explained how exactly 2D canted TVC nozzles in conjunction with the aerodynamic controls are operating (which was confirmed by the official papers), only shows that I actually know what I'm talking about, unlike you who have claimed exactly the opposite.

    GarryB wrote:
    Is is often the case when quoting you leave something out that doesn't support your case in a discussion... you make bold sections hoping that the other parts are not considered but I would say it was that last sentence you should have made bold... all the requirements are contradictory and the creation of an aircraft that meets such requirements represents a certain compromise. In other words quite a few angles of vertical tail surface would reduce RCS from the side, but this particular angle that they chose might offer the best aerodynamic and control performance as well as reduce RCS... which is all I was saying.

    That is not the case, since I didn't leave that part out, I have quoted that as well! Are you retarded, or can't read, or both?!

    I have bolded the part about edge alignment, among others, to show that the main reason for the edge alignment comes from the RCS reduction requirements, and that is exactly the thing that they made compromise over, since you don't need a single surface to be aligned if you are aiming just at the best performance for the plane.
    And of course they also had flight performance on their mind when they were calculating the angle of the edge/platform alignment, but that angle has nothing to do with the canted angle of the TVC nozzle for two reasons.
    First, the angle is not the same as evidenced!
    Second, the canted angle of the nozzle is calculated based on the best compromise between pitch and yaw/roll authority in relation to the planes Cg and the distance between the engines, and there is absolutely no reason on earth for them to try to align the rudder with the nozzle, and vice versa, since that would compromise entire RCS of the plane (in the case you want to align the rudder and airframe side edges with the nozzle), and would also compromise the flight performance (in the case you want to align the nozzle with the rudder).

    You just had "bright" idea when you saw that the nozzle canted angle is the "same" as the rudder angle, and you started to develop your own theories.
    And I don't have nothing against theories and ideas, but when they don't match reality, you should leave it at that and go on with your life!

    GarryB wrote:

    You can't say that just from that piece of text. The next paragraph about the aerodynamics might mention the bonus to the angles chosen for the vertical tail and the engine alignment allowed improved manouverability because their axis of moment was aligned greatly simplifying the control inputs to both control mediums in the flight control system which is rather more complicated in the Su-35 because the tails are vertical and not all moving like the angled all moving surfaces on the Su-57.

    Not only that you don't have clue what are you talking about, but you are actually making the stuff up that is not written in the patent text!
    In reality it is far more easier to make the FCS algorithms for the plane with the vertical rudder, than for the plane with the canted V rudders.
    Unlike vertical rudders, canted rudders have vertical and horizontal component, and when they deflect in one side, they provide yawing moments, but at the same time they also induce roll since one rudder is creating lift, and the other rudder is creating down-force. In order to counter unwanted roll moments, you need more complex control laws that will send information to other control surface to deflect in order to counter/stop the roll, and in turn all this will create more drag and torsion stress to the airframe.

    If you want to find out more about downsides and benefits of the V tail, here is the link:

    https://www.kitplanes.com/design-process-v-tails/

    GarryB wrote:

    But even if we go with the flow, X-31 using external paddles is providing superior yaw rates than for example J-10B with genuine 3D TVC. And even then the differential canard deflection in conjuction with the rudder is providing almost the same force in the range of angles going from 0 to 80 deg!

    Are we not going to discuss how the X-31 with a single engine that fakes TVC with external paddles generates less roll control than the canards fitted to its nose?

    I mean I fully understand how the differential use of nose mounted canards would would create roll control forces, but how exactly does a single engine with three paddles achieve that?

    For reasonable people there would be no need to discus that, since the undeniable fact that the aerodynamic control surfaces can provide the forces in post stall region of about equal power to the TVC nozzle is brutally disproving your rant how they are useless for the post stall maneuvering!
    But just to show you how you don't understand absolutely nothing, I will explain how TVC on the single engine plane can provide roll control.

    Here is the data for the F-16MATV CLAW:

    Su-57 Stealth Fighter: News #8 - Page 39 Mv10

    Su-57 Stealth Fighter: News #8 - Page 39 Mav10

    It is obvious that for conventional AoA region you don't need the TVC for roll/yaw control since the aerodynamic control surfaces are adequate, and the CLAW for the roll/yaw control is blended back to the baseline F-16 laws.
    Above the AoA where aerodynamic control surfaces can't provide necessary stability/controlability TVC kicks in, and since the roll at higher AoA is not going directly trough longitudinal axis, but it is the blend of the longitudinal and perpendicular axis, you can also use the rudder and 3D TVC nozzle to control the roll.

    Here is how the F-16 roll looks like at 25 deg. AoA



    Su-57 Stealth Fighter: News #8 - Page 39 Aoa10

    You can see that the plane is rotating around its velocity vector, and in doing so, we can see that the tip of the nose, and the end of the plane are making circular motions. You can easily induce, or control the roll with the 3D TVC or rudder at the back of the plane, or with the control surfaces such as the LEVCON's at the front of the plane, at such conditions. As the AoA is increasing rudder is losing authority and you can basically roll the plane just with the nozzle, but depending on the AoA the roll command mixer is distributing roll command to appropriate control surface (in this case differential tail, rudder, flaperons, and TVC) for the most optimal performance gain for the F-16.

    And this is who knows what time that the official documents are confirming the fact that the aerodynamic control surfaces can be, and are used for the post stall maneuvering, which is in direct contrast to what you have been claiming.
    But I have no doubt whatsoever that you will find the way to try to spin this around as usual with the new load of nonsense claims!

    GarryB wrote:
    The aircraft is controlled in the side channel by means of differential deflection of the jet nozzles 14, which simultaneously create a roll moment and a yaw moment, while the roll moment is countered by the deflection of the aerodynamic controls (10 ailerons and 11 flapperons). Control of the aircraft in the transverse channel is carried out with differential deflection of the rotary jet nozzles 14, creating a roll moment relative to the center of mass of the aircraft."

    {sarcasm}So you are continuing to try to tell us that the 2D vectored thrust engines can contribute yaw and bank and roll effects if the engine is canted... thanks for that... that is new... we never thought that before {/sarcasm}

    I like your sarcasm, it makes you look even more stupid!
    I have presented that particular quote from the PAK FA patent because they also claim that the aerodynamic control surfaces are used to counter unwanted roll motions made by the differential nozzle deflection.
    So, they also confirm what I was saying, and this is another prove that the aerodynamic control surfaces can arrest/counter roll moments created by the differential nozzle deflection of the two engine fighter, and they prove their role in post stall maneuvering. This again is brutally contradicting your convoluted mess of claims.
    I have bolded that part again, just so that you can't miss it like you conveniently did the last time!

    GarryB wrote:

    Don't you find it interesting that before you started posting on this thread Mir and I were disagreeing, but now we are both unable to read or write (illiterate) and know nothing on the subject you appear to have invented and have been discussing since the internet started.

    The only difference between you and him is the fact that he thought that there are some "left and right" movements of the 2D TVC nozzle, but both of you had no idea how that 2D TVC canted nozzles are actually operating in conjunction with the aerodynamic control surfaces.
    And you have also added your theories about rudder and nozzle angle which are totally baseless.

    GarryB wrote:

    At 34:15 F-22 pilot i

    Not really interested in what the youth of America have to say on the subject. This is not an insult... it is just a fact.

    I don't have any reason to be insulted, and I don't think he is either, but the pilot is actually explaining how control laws of the F-22 are operating, and he is 100% right, and that is the fact!
    Do I need to say that this is also another prove that you have no idea what are you talking about, since the F-22's elevators are actually inducing and controlling the yaw motion during the deep post stall maneuver?!

    GarryB wrote:

    I thought DUDE was more appropriate than WTF Ngger... but you have judged us both illiterate, yet you continue to post pseudo facts and videos of American pilots... the contradiction there is a fact, your opinion of our understanding of anything is not a fact in any sense... it is an opinion.

    Yes, both of you are illiterate on the subject, and I have presented nothing but the facts in the form of the official papers, screen shots, and documents that totally disprove you, and the video of the F-22 pilot was my attempt to present the facts in more simplified manner, because you have the video of the plane doing flat spin, and him explaining every sequence with the toy and hands, and what not.

    You can't get better than that, but if that is to complicated for you, I can't help you anymore!

    On the other hand you have presented nothing, not a single link, not a single claim that would make any sense, and you talk about pseudo facts?! Insane!
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    Su-57 Stealth Fighter: News #8 - Page 39 Empty Re: Su-57 Stealth Fighter: News #8

    Post  GarryB Mon Jan 22, 2024 6:30 am

    IMO the main reason they didn't upgrade f22 was price not self confidence.

    I rather suspect they knew how flaky it was to risk everything on stealth like that which has quickly turned into a total failure because modern missiles should get a lock and track stealthy targets.... IRSTs seem to be able to detect B-2 bombers at airshows... and short and medium and long wave IR technology has moved on to where it is rather capable against targets with near zero RCS.

    Remember storm shadow and various HIMARS and other systems are supposed to be stealthy and impossible to intercept, yet reality begs to differ.

    It is already very expensive to have and operate. The upgrade would skyrocket the price.

    The promise of the F-35 was that everyone would use it and being a single engined fighter it would be light and cheap and they could take advantage of the fact that everyone was using it so you could pool your spares to greatly reduce support problems and make support easier and cheaper and more effective.

    Of course it has been none of that and is the most expensive weapon programme in the west so far.

    Is Gonads going for the record?


    I think you just had a brain fart, because everything you have just said has nothing to do with the fact that the Su-57 canted angle of the nozzle is not the same as the angle of the rudder, which is exactly what you have claimed over and over again, and exactly what you have based your unfounded theory on!

    I think that perfectly explains why we are still discussing this... do you understand the concept of vertical and horizontal planes?

    The 2D TVC of the engines is up and down and the direction of effect for the vertical rudder on the Su-57 is left and right... the fact that they are perfectly aligned or the fact that they might be off by 10 or even 15 degrees does not matter... the engines act on one plane and the rudders act on the other... the fact that the vertical tail surfaces on the Su-35 are not perfectly matching the cant of the engines doesn't matter a lot, but it makes calculations for different force effects different than if they were aligned perfectly with the engine nozzles. The Su-57 does not seem to have perfectly aligned rudderons and engine cant, but the fact that the tail fins are angled and more closely match the engine cant would make the deflection calculations of both devices SIMPLER.

    That was all I was saying.

    In reality the canted angle of the nozzle and angle of the rudder are not the same. It is simple as that, no additional comments are needed, thanks!

    The angles for the Su-57 are close enough to not matter that they are not precisely the same... for the same reason that the vertical tail of the F-18 and MiG-29 are angled out slightly but that does not prevent them from acting as rudders... because the few degrees angling makes no difference and can be compensated for by the pilot or the flight control system.

    I am familiar with the most control laws applied to the planes with the TVC, and the fact that I have more than decade ago explained how exactly 2D canted TVC nozzles in conjunction with the aerodynamic controls are operating (which was confirmed by the official papers), only shows that I actually know what I'm talking about, unlike you who have claimed exactly the opposite.

    Are you saying I have spent more than a decade explaining 2D canted TVC nozzles don't operate with how aerodynamic controls?

    That is not the case, since I didn't leave that part out, I have quoted that as well! Are you retarded, or can't read, or both?!

    You left it in but are ignoring what it means and how that relates to what you put in bold. You highlighted the bold part which supported what you said and included but otherwise ignored the rest of it which supported what I was saying... and then claimed it proved me totally wrong.

    I have bolded the part about edge alignment, among others, to show that the main reason for the edge alignment comes from the RCS reduction requirements, and that is exactly the thing that they made compromise over, since you don't need a single surface to be aligned if you are aiming just at the best performance for the plane.

    You applied the bold feature to emphasise the bits you thought were important and to distract from the rest which changed the meaning of what you put in bold.

    I am not saying they aligned the control systems to get better flight performance, I am saying the alignment would make the flight control algorithms simpler.

    Second, the canted angle of the nozzle is calculated based on the best compromise between pitch and yaw/roll authority in relation to the planes Cg and the distance between the engines, and there is absolutely no reason on earth for them to try to align the rudder with the nozzle, and vice versa, since that would compromise entire RCS of the plane (in the case you want to align the rudder and airframe side edges with the nozzle), and would also compromise the flight performance (in the case you want to align the nozzle with the rudder).

    You are a ten year plus expert and you say this shit?

    A flight control system doesn't work by ignoring the situation at hand... the inputs from the pilot need to be interpreted by the flight control system to work out what the pilot wants to do and will do different things at different speeds and flight situations.

    In level forward flight at normal flight speeds at medium altitude pulling back hard on the stick the flight control system is going to use various control surfaces to achieve that flight command... but if the aircraft is flying forwards or backwards or sideways, whether it is 1m above the ground or 20km above the ground, whether it is supersonic or in a super stall will determine what the flight control does to try to perform that manouver.

    Having control surfaces roughly aligned makes the required movement controls to the rudder and aelerons and engine nozzles simpler.

    If they are not aligned then it will still try to do the same thing but a different combination of control surface deflections and nozzle angle adjustments would be needed to be made... the pilot likely wont know or care, it would only be the guy who wrote the FCS that would know what is going on.

    You just had "bright" idea when you saw that the nozzle canted angle is the "same" as the rudder angle, and you started to develop your own theories.
    And I don't have nothing against theories and ideas, but when they don't match reality, you should leave it at that and go on with your life!

    Essentially correct, and all you had to say was that you disagree and it would all have been over, because honestly it was an off the cuff comment that I have not spent over a decade talking to aviation experts trying to formulate and work out.



    Not only that you don't have clue what are you talking about, but you are actually making the stuff up that is not written in the patent text!
    In reality it is far more easier to make the FCS algorithms for the plane with the vertical rudder, than for the plane with the canted V rudders.
    Unlike vertical rudders, canted rudders have vertical and horizontal component, and when they deflect in one side, they provide yawing moments, but at the same time they also induce roll since one rudder is creating lift, and the other rudder is creating down-force. In order to counter unwanted roll moments, you need more complex control laws that will send information to other control surface to deflect in order to counter/stop the roll, and in turn all this will create more drag and torsion stress to the airframe.

    If you want to find out more about downsides and benefits of the V tail, here is the link:

    HAHAHAHAAHAHHA... so what you are saying is that canting the rudders makes the flight control model more complex and more difficult... so maybe aligning the 2D thrust vector nozzles to a similar but not the same angle might make those calculations similar because you are aligning control surfaces and thrust vector angles... which is why I made my comment.

    But obviously I am wrong because you said so, even though you are posting things that agree with what I said...

    But just to show you how you don't understand absolutely nothing,

    That can't be true, because I realise you meant to say I know nothing at all (which is what absolutely nothing means), which is kinda impossible as I am using a computer to communicate to you in English which is clearly not nothing, but also your double negative actually means the opposite of what you were trying to say. You are saying I know everything which is also not possible.


    I like your sarcasm, it makes you look even more stupid!

    I used sarcasm tags to avoid communication problems that can happen on the internet where one party does not understand the other person is being sarcastic.

    If you think being a better communicator makes me stupid that is OK, again you are entitled to your opinion, but you are typing lots of stuff and posting lots of diagrams and videos to someone you claim to think is stupid.

    Who is being stupid?

    The only difference between you and him is the fact that he thought that there are some "left and right" movements of the 2D TVC nozzle,

    It is not the worst crime in the world, they have 3D engine nozzles... Klimov have shown them on their MiG-29OVT, and I think a lot of people see such things and assume it is all in service and that this is a nut they have cracked.... all through the early 2000s I thought the Russian military had lots of things in service that it turns out only was displayed at airshows and was never put into operational service. They are only now putting APS systems on their tanks despite testing them in Afghanistan in the 1980s.

    Sometimes things appear amazing but there are problems or issues that lead to them staying in the lab till those problems can be solved and I rather suspect 3D jet engines might be one of those things.

    For decades the Russians and Soviets have had electronically scanned radars, but they seem to be very slow on the uptake of AESA radar arrays... because they are expensive and I suspect don't offer an enormous leap in performance to the radar currently in use which include PESA types.

    It seems to be the same for 3D TVC engines.

    The Su-35 and Su-57 and the MiG-35 were all supposed to have TVC engines but I have seen no confirmation that the MiG-35 does have such engines.

    The MiG-35 was also supposed to introduce an AESA radar as well and most people seem to think that is not in use either.

    Who knows... not anyone here for sure, and if they knew I am not sure they would be allowed to say.

    That is why we chat and speculate and share photos and videos and information.

    I don't have any reason to be insulted, and I don't think he is either, but the pilot is actually explaining how control laws of the F-22 are operating, and he is 100% right, and that is the fact!
    Do I need to say that this is also another prove that you have no idea what are you talking about, since the F-22's elevators are actually inducing and controlling the yaw motion during the deep post stall maneuver?!

    Many in the west think the word of western experts, whether they are armchair experts or pilots etc, is sacrosanct and that dismissing their views is blasphemy.

    The simple fact is that western military experts don't understand Russian equipment and don't try to and just evaluate it compared with their own... which is why the Ukraine has been getting its arse handed to it these last two years.... first with Soviet gear and tactics, and then when that was used up and burnt out with HATO equipment and tactics... which seems to be almost gone now too.

    For the rest of the world the high esteem the western military experts were held in has been deflated... they still know how to apply violence and murder and death around the world, but now they are not so invincible as they once appeared to be.

    Some westerners don't like such things and get insulted.

    You can't get better than that, but if that is to complicated for you, I can't help you anymore!

    I am stupid remember... why are you wasting your time?


    On the other hand you have presented nothing, not a single link, not a single claim that would make any sense, and you talk about pseudo facts?! Insane!

    I made a comment on an internet forum, but because I can't back up that off the cuff comment with links and videos and perhaps an infomercial or two I have committed a crime now?

    Interesting.

    And you say I am stupid?

    Big_Gazza likes this post


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