Su-57 Stealth Fighter: News #7

If the fins are small and the body does not generate lift, the missile would not fly.

If cylindrical bodies and fin strakes generate lift then why to bullets and tank gun rounds have a ballistic trajectory... surely HEAT FS has a cylindrical body and stabilising fins... why does it continue to fall after it leaves the barrel requiring the barrel to be elevated and the point of aim at the target determined by range to the target?

Indeed if you look at the sight reticle of an RPG-7 rocket launcher if body lift was a thing and the large stabilising fins at the tail generate lift why does the range scale show the rocket descends all the way to the target... therefore requring further and further shots to be aimed higher and higher to reach said targets?

The RPG-7 is particularly interesting because after being blown out of the launch tube after a short flight its rocket motor lights up and it is accelerated to much higher speeds... I seem to remember a launch from the tube at about 185m/s but after 10-12 metres or so the rocket motor then accelerates the rocket to supersonic speed... 375m/s or so... yet looking at the RPG-7s aiming reticle as range increases the rocket drop continues... there is no plateau where lift maintains the rocket and allows it flat shooting ballistics...

A long range missile like a cruise missile uses wings for the same reason an aircraft uses wings... an AAM uses angle of attack to direct its low thrust sustainer motor to maintain height and speed by angling up slightly and therefore pointing its low thrust sustainer motor downwards for both forward speed and altitude maintaining lift... missiles that don't have that sustaining thrust have much shorter range because their height maintaining angle of attack costs them in speed so they slow down faster to maintain altitude.

Of course they need the robustness and stability to eject the missile, maybe under load, high speeds, vibrations, etc. Those loads are no small thing and only sufficient arm width can handle them.

It is the fact that the arm launcher pushes them down and clear of the aircraft that they could fit them very close together...



Look at the image above... the space between the missiles is enormous... you could easily put a pylon down the centre between the two missiles that extends below the two other missiles. Obviously in use that lower missile would have to be used first because the other two missiles wont be able to be launched past it, but if they are all the same type of missile that is not a problem. Horizontally the only problem would be the rear grid fins, but the obvious solution is to have them folded and deploy them only after the missile is clear of the weapon bay. The lower missile could be mounted slightly further forward or back too if need be.

Planes don't fly alone and salvos are regularly used, so no big deal.

Firing four missiles at every target sounds a bit counter productive most of the time... four missiles with four seekers and four sets of ECCM per launch missile would make it rather expensive too.

I would think a missile with multiple terminal stages would be kept in reserve in case of full scale war and not carried routinely most of the time.

Enemy cruise missile attack or mass drone strike, but against enemy fighters I can't see it... would be interesting with a larger R-37M missile with 6 mini missiles on board... become an ace with one pull of the trigger...

In therms of self defence, some different, short ranged missile of which many can be carried would be ideal, maybe a higher calibre gun with guided rounds would be even better?

The 9M100 is probably going to be the basis for the mini missile mounted in their AAMs considering four of them fit in the 9M96 launch tube and four 9M96 fit in a single S-300 launch tube I rather suspect we already have a hint of what is coming... air launched S-400 missiles of the large 250km and 400km kind carrying four 9M96 missiles each with an independent 150km range.... except launched from high altitude and high speed I would think their flight range would be much much higher... though of course their launch would be much less than 250km or 400km because four 9M96 is a much heavier payload than the original 150kg payload... say perhaps a 100km range from the base missile launches the 9M96 missiles to 20km altitude and mach 3 or mach 4... which means their 150km flight range should be doubled at the very least to 300km so we are talking about 400km range missiles that can start engaging targets at 100km with ARH high performance missiles.

Of course it really gets fun when you take it a step further because for each of those 9M96 missiles you could have four 9M100 missiles which means one big missile could have say two 9M96 long range missiles and 8 9M96 shorter ranged missiles... or just 16 shorter ranged missiles.

Or you could have 9M96 missiles that carry four 9M100 missiles...

The 9M100 missiles would be ideal as short range self defence missiles that can immediately attack a threat... the problem with using a big heavy missile carrying mini missiles is that most threat missiles are not likely to be detected at 100km away... most of the time they will be much closer...

We are back to AoA.

So what you are suggesting is that if bullets were stabilised with a nose up attitude then they would fly straight and level all the way to their targets?

All bullets are lofted into the air towards their targets via the sighting systems on most firearms and guns, so they start with their noses pointing upwards anyway...

Thrust goes in line with the axis of the missile therefore it does not produce lift, this is a misconception.

So flaring on takeoff of course massively increases wing lift, but you then have to ask why Harriers vector their engine nozzles to 45 degrees on takeoff... you try to tell me canards generate lift but tail surfaces detract from lift...

This is all off topic.

1. The 40 cm available do not allow to stacking missiles with 20 cm diameter + fins

What 40cm available?

Take the 2 main suspension points, crate double ejectors for each of them and you get the same number of missiles with much simpler mechanics that if you stack two up and two down.

The mechanics are not different... four missiles needs four ejectors... whether they are all together in the same plane or staggered in two layers.

That is always substantially cheaper than 1 modern fighter with a pilot that has required years long training.

A much smaller lighter aircraft that is essentially all fuel and radar could find air targets and hand them off to ground based missiles even more cheaply.

And as said targets are hardly alone, you keep ignoring that, but the kinematic architecture of the multimissile allows to attack even targets that are relatively distant from each other, so even tactics countering them (spreading the planes in a wing) would be difficult to implement practically.

You seem to expect there to be thousands and thousands of targets in the air all the time needing each launch to take down the enemy four at a time sounds like you think western plans for Swarm drones are something that will actually happen...

The thing is though, that if that is a reality then Russian swarms will be cheaper and probably produced in much greater numbers... and probably actually effective so they fighters might not even be needed.... Russian swarm drones take down western swarm drones and then wipe out their air forces which they base their defence and attack capacity on.

Russia already has an enormous ground based air defence advantage over HATO, with HATO tanks and aircraft outnumbered 50 to one by Russian missiles... do you think making lots of drones will suddenly render an air defence system based on fighter planes and AWACS aircraft omnipotent and all powerful.... while a properly designed and layered fully integrated air defence network with networked in fighters and strike missiles and aircraft and drones is suddenly vulnerable and weak?

But if you are in the middle of high intensity fighting this is what provides the best capability, by far.

History tells us that the Afghans and ISIS don't have the aircraft for high intensity fighting, and in the case of HATO, well it is going to go nuclear soon enough that it wont matter.

Anything launched from land has a booster way bigger than it would be ultimately needed with air launching, so you could get by with smaller missiles, since range requirements are completely undemanding,

Quite true but if you are launching 9M96 sized missiles from an R-37 sized launch booster the R-37 will lose most of its range because 9M96s are much bigger and heavier than the normal payload of that missile... so while the range of the 9M96 in such a situation will likely double at least or perhaps quadruple like the Iskander did in the version of the Kinzhal, the boost range the R-37 reaches will also be dramatically reduced as well... so it wont be a case of R-37 = 350km plus 9M96 middle missile is 60km times say 3 is 180km so about 530km range total range.

The R-37 range will reduce quite a bit to maybe 100km but good altitude and speed for launching the 9M96 missiles... the max range wont be much different to the 300-400km range of the original but obviously with the advantage of 3-5 mini missiles each able to target something on its own.

I would think the best choice for carrier booster would be a rocket ramjet design that can climb and cruise at an efficient speed and then as it gets closer to targets accelerate to give max energy to released guided missiles.... but releasing them close to their targets they will have plenty of energy anyway.

Maybe the new anti-UAV ones designed for Pantsir would be of application too.

The long solid rocket booster would be a bit redundant, perhaps the new TOR minimissiles... though they might be much smaller and two stage as well.

The point is that the 9M100 is already very small and slim and with a TVC rocket motor with likely multiple stages and an IIR seeker and two way datalink and lock on after launch capacity it is already a good contender for self defence missile for air ground and naval vessels... I would think it would actually be a very potent weapon for submarines as a last ditch effort against MPAs and enemy helicopters...

GarryB wrote:

If the fins are small ĺĺ the body does not generate lift, the missile would not fly.

If cylindrical bodies and fin strakes generate lift then why to bullets and tank gun rounds have a ballistic trajectory... surely HEAT FS has a cylindrical body and stabilising fins... why does it continue to fall after it leaves the barrel requiring the barrel to be elevated and the point of aim at the target determined by range to the target?

Indeed if you look at the sight reticle of an RPG-7 rocket launcher if body lift was a thing and the large stabilising fins at the tail generate lift why does the range scale show the rocket descends all the way to the target... therefore requring further and further shots to be aimed higher and higher to reach said targets?

The RPG-7 is particularly interesting because after being blown out of the launch tube after a short flight its rocket motor lights up and it is accelerated to much higher speeds... I seem to remember a launch from the tube at about 185m/s but after 10-12 metres or so the rocket motor then accelerates the rocket to supersonic speed... 375m/s or so... yet looking at the RPG-7s aiming reticle as range increases the rocket drop continues... there is no plateau where lift maintains the rocket and allows it flat shooting ballistics...

A long range missile like a cruise missile uses wings for the same reason an aircraft uses wings... an AAM uses angle of attack to direct its low thrust sustainer motor to maintain height and speed by angling up slightly and therefore pointing its low thrust sustainer motor downwards for both forward speed and altitude maintaining lift... missiles that don't have that sustaining thrust have much shorter range because their height maintaining angle of attack costs them in speed so they slow down faster to maintain altitude.

I feel that your discussions are always back to square one because there is a critical aspect of physics missing: Inertia.

Unpowered projectiles initially assume the direction of throw imparted by the guiding mechanism (such as the bore of a gun) and keep decelerating due to air friction in the horizontal direction while in the vertical direction keep accelerating downward due to gravity. Hence the parabolic flight path back to ground. You can imagine throwing a stone. Inertia is imparted to it only once by your hand.

Powered projectiles are a bit different. Imagine throwing the stone, catching it mid-flight again, and throwing it again in the same direction. It will gain a whole new life of Inertia and start over. Now imagine doing that again and again continuously. This is called inertial propulsion and is what keeps rockets without lifting surfaces afloat. They use control surfaces to create an air resistance imbalance in a chosen axis to change direction. They can also achieve that by vectoring their thrust to point their noses as required. This works precisely because it is a continuous propulsion system and while rotating the nose by itself doesn't change the direction of the Inertia, after rotating it the engine imparts a new Inertia vector in the new direction.

That being said, I am not sure how symmetric control surfaces as shown on some of the diagrams in your conversations can generate lift. Lift generating aero foils necessarily need to be non-symmetric in at least the axis of flight in order to achieve an air pressure differential in the axis perpendicular. Fixed symmetric surfaces are used for stabilization of flight path, while movable ones are used for aerodynamic imbalance to change the flight direction by orienting the vehicle in the needed direction and the engine imparting new inertia in that direction. Note that movable fins are usually positioned on the front or rear of the vehicle so as to get a good lever length from the center of mass of the missile.

LMFS wrote:

This may sound strange but most of what is normally told about what makes planes fly is wrong. They do not fly because of pressure or speed differences between upper and lower surfaces of the wing but by the transference of linear moment from the air to the wing. Symmetric wings do work, see the examples above, because what is relevant is the AoA. How could a plane fly inverted if the asymmetrical profile is mandatory? Viscosity of the air bends it following the wing's profile and the wing's angle to the airflow sends it downwards, it is that easy. Of course if today most people don't know this, imagine how difficult was to figure it out hundred years ago and how long it did take to design proper wings and aero design in general.

You are right that a positive angle of attack can generate lift. It is the same principle as creating an aerodynamic imbalance to change direction, only here just enough imbalance to keep the plane level against gravity. In fact some smaller planes are made with fixed positive AoA with symmetric wing profiles. This helps in flying inverted (not merely rolling) for aerobatic teams.

The problem with fixed +ve AoA is it is aerodynamically inefficient when compared with the bernoulli aerofoil due to a greater surface area of the wings being in the flight path and hence constituting a drag. It also is cause for more noise and vibration. That is why modern airliners are designed with little or no AoA in their wings. If a large airplane needs to fly inverted for one reason or another, it needs to point its nose upward so as to create an AoA that generates lift plus counter the bernoulli force which is now acting downward.

This works precisely because it is a continuous propulsion system and while rotating the nose by itself doesn't change the direction of the Inertia, after rotating it the engine imparts a new Inertia vector in the new direction.

Most solid rocket powered missiles burn out in a few seconds... the long range ones have very low power rocket fuel which essentially works like a base bleed system on an artillery shell and reduce drag rather than provide actually provide thrust.

The initial phase of a long range missiles flight is to climb to great heights and accelerate to high speed... height because the thinner colder air offers less drag to any moving object and very high speed because without full thrust that is what is going to be bleeding away while trying to maintain height.

That being said, I am not sure how symmetric control surfaces as shown on some of the diagrams in your conversations can generate lift.

Especially with a rolling missile which many do roll in flight.

Even a shape as antiaerodynamic as a bullet would generate more lift with some degrees AoA than flying 0 deg

So you are suggesting a brick with a useful AoA will fly further than one angled for the most drag... I would agree, but I would also say the difference in flight performance would really not be enough to actually care much about. The high drag brick will slow down faster and wont travel as far, but so what?

You are confusing angle to the ground with angle to the axis of movement, which is what AoA means.

No I am not. Bullets are spin stabilised and wont necessarily windcock to point the point of the projectile in the direction it is travelling in, so as they start to descend the nose does not point downwards in the new direction of travel, so the projectile should gain in AoA as it slows down and starts to head at a sharper and sharper angle towards the ground.

40 cm is the max vertical space available to weapons in the Su-57 bay, the rest goes to the pylon/ejector, clearances and bay doors.

Is that number official or an estimate?

Does it include the pylon and are these pylons flush with the upper space or do they hang down and therefore have space above for strakes to fit into?

Tor idea is good too, still we have not seen the size of the missile, or have we?

Not the new mini anti drone missile no.

The missile from the mid 1980s was over 300kgs, but the upgraded newer model with 16 missiles per vehicle should be smaller... even Sosna would be interesting...

Those missiles are very nice because of their independent targeting and hence intrinsically very high saturation threshold. They will be expensive too I assume.

They would essentially have QWIP sensors, which would be the equivalent of a CCD light sensor chip that detects normal visible light as well as UV and IR frequencies too. A bit of image processing and it should be a very very capable sensor... and with production for naval forces (in Redut launchers) for the Army (in dedicated 9M100 launchers) and the Air Force (air to air missile and also in the S-350 air defence ground system too) they are going to be making a lot of these missiles.

How could a plane fly inverted if the asymmetrical profile is mandatory?

A MiG-29 can fly down a runway in a 90 degree roll angle with one wing pointing up and the other pointing down but with the nose yawed to above the horizon and the engines therefore angling down and maintaining height...

Robust structures ejecting 700 kg cannot be tiny.

Their size is irrelevant.... when not in use they are inside the internal pylon and when extended the bay doors are open and the munition has already been pushed down and out of the bay.

Excellent, mixed regiments as we discussed... the UACV as an "accessory" of the Su-57, very promising in military terms but will also demand a serious doctrinal adaptation that will be interesting to follow. Who knows if also unmanned fighters can be added to the mix in the future

A drone that operates with a multirole aircraft would already be a fighter and a strike platform and recon and jammer and everything else...

The new weapons belong to the "air-to-surface" class, they are designed to hit such priority targets as enemy air and missile defense facilities, radar stations, cruise and tactical ballistic missile launchers.

So could be a single stage air launched next gen Hermes missile with ram or scramjet propulsion or equivalent...

The okhotnik can play a very good role in terms of counter stealth. You have a few drones broadcasting radar waves and Su-57's picking up the normally deflected return in a bi static manner.

Also , okhotniks scanning a broad area with L-band radars while the 57's focus their optics on a small sector for long detection range. Ship based Optics from 2010 could already track air targets from 100 km. So the OLS systems on the Su-57 would have an enormously long range considering they are far newer and of higher profile (situation awareness asset for a fifth gen fighter vs short range fire control on a ship)

From vlad vlad on Twitter

Backman wrote:From vlad vlad on Twitter

https://pbs.twimg.com/media/Eub9W-hXMAo2hs1?format=jpg&name=small

What the heck is this supposed to be?

PapaDragon wrote:

Backman wrote:From vlad vlad on Twitter

https://pbs.twimg.com/media/Eub9W-hXMAo2hs1?format=jpg&name=small

What the heck is this supposed to be?

A cross between the Su-57 and Boeings YF-23 (competitor to Lockheed's YF-22/F-22A). And yes, I know what your thinking....it's definitely an abomination.

Isos wrote:Quality of manufacturing of serial build su-57 compare to prototypes. I guess they will have a nice surprise concerning the RCS.

No doubt the obstruction of rivets will be less obtrusive in the serial models, but the funny thing is the rivets on the Su-57 prototypes are still less obtrusive than serial versions of F-22A's lol!

PapaDragon wrote:

Backman wrote:From vlad vlad on Twitter

https://pbs.twimg.com/media/Eub9W-hXMAo2hs1?format=jpg&name=small

What the heck is this supposed to be?

Its a cross between a su 57 and YF-23 and it sorta works. Because they are both blend wings

Isos wrote:Quality of manufacturing of serial build su-57 compare to prototypes. I guess they will have a nice surprise concerning the RCS.

This picture confirms more stuff , actually.
The rivets are flushed on the OLS section.
In other words , the small tiny rivets would've made an unwanted increase in RCS that sukhoi did not want.
By deduction , the OLS itself is stealthy , Because if an RCS increase caused by a tiny rivet was inacceptable , the big OLS is then sure to have some coating within the glass or Internal components that lower the RCS to a level in which even an exposed rivet would make it spike. (Very low)

Let us put it this way. Imagine someone fixing a car that crashed and broke and now he's in the last stages of that.
If you see him fine tuning the cup holders then that means that the bigger issues such as engine and transmission damage have been solved a long time ago or else he wouldnt care about small details if the big issues had not been tackled.

But its the Internet, people think that sukhoi has to prove itself to the almighty Internet judges and that any claim they make has to be doubted as opposed to LM statements being Taken as absolute truth

I don't see it like that. Sukhoi obviously will try to cover as many roles as possible with the Okhotnik, but the platform is not a fighter and will never be. In the future I can imagine mixed regiments where different types of UCAV are available depending on the missions as a complement to the Su-57.

Well you can have all sorts of definitions of a fighter... an interceptor is a type of fighter and does very little dogfighting, but shoots down enemy planes which is the core of what a fighter is for... were Hurricanes not fighters because they shot down bombers during the Battle of Britain, while the Spitfires focussed on the enemy fighters?

The easiest way would be a reduced size Kinzhal, launched from high altitude and close to 2 M from the Su-57 it may enough distance for a tactical weapon. Of course scramjet CMs would be even better and longer ranged.

A reduced size Iskander makes little sense... air or ground launched. A tactical Zircon might be interesting... much like the modifications of Brahmos they keep talking about for tactical fighters to carry in numbers...

From vlad vlad on Twitter

Yuk.

A cross between the Su-57 and Boeings YF-23 (competitor to Lockheed's YF-22/F-22A). And yes, I know what your thinking....it's definitely an abomination.

Yet they pretended that the F-32 was one of those and the F-35 was the best choice.... hahahahaha.

Quality of manufacturing of serial build su-57 compare to prototypes. I guess they will have a nice surprise concerning the RCS.

The difference might just be a light coating of RAM...

Isos wrote:Quality of manufacturing of serial build su-57 compare to prototypes. I guess they will have a nice surprise concerning the RCS.

And dumbasses have the temerity to suggest it has the RCS of a clean Rafale. Delusional morons.