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    Su-57 Stealth Fighter: News #6

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    Post  LMFS Mon Jul 27, 2020 11:50 am

    The bays are more than 1.15 m wide. 2 MRAAMs 20 cm diameter fit comfortably, 2 heavy weapons 40 cm diameter fit too. The only issue are the fins, other than that it could fit three or even four MRAAMs side by side (drawing by Paralay IIRC)

    Su-57 Stealth Fighter: News #6 - Page 9 Image_11

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    Post  Isos Mon Jul 27, 2020 12:23 pm

    R-77M = 200km range.
    R-37M =300-400km range.

    Their rcs is as small as 0.1m2 or less.

    They are meant to be launched from far away. Su-57 can carry one under each wing and stay invisible to radars at such ranges. Of course they would be the first to be launched so it will reduce its rcs while closing to the target.

    And to be sure that it doesn't affect its rcs the su-57 can stay bellow the enemy so that the airframe hides the missiles from the enemy's radar.
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    Post  GarryB Mon Jul 27, 2020 2:18 pm

    The real question is the wiring... wiring for three narrow missiles and two fat ones would be interesting, but then if you stagger them and have them mounted a different heights the narrow missiles could actually overlap... the external pylons for the R-77 have a pneumatic arm that throws the missile down clear of the aircraft before its rocket motor lights up... I would expect the same mechanism on an internal bay so the missile clears the aircraft properly which means you could overlap thinner missiles by hanging some lower... once they are launched then the upper missiles could be launched the same way without the lower missiles in their way... and with that in mind you could probably fit up to 5 missiles per main weapons bays and of course two light missiles inside the wings for 12 missiles without using external weapons points.

    In theory then with 6 R-37Ms on the missiles which can be launched first to get back to stealthy, you could then have 5 R-77Ms in the rear weapon bay and two more R-37Ms in the front bay and two R-74s in the wing bays... or just 10 R-77Ms in the central weapon bays and two R-74s in the wings...
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    Post  LMFS Mon Jul 27, 2020 7:35 pm

    GarryB wrote:The real question is the wiring... wiring for three narrow missiles and two fat ones would be interesting, but then if you stagger them and have them mounted a different heights the narrow missiles could actually overlap... the external pylons for the R-77 have a pneumatic arm that throws the missile down clear of the aircraft before its rocket motor lights up... I would expect the same mechanism on an internal bay so the missile clears the aircraft properly which means you could overlap thinner missiles by hanging some lower... once they are launched then the upper missiles could be launched the same way without the lower missiles in their way...

    By coincidence I checked that already   angel

    There is not enough space, due to the thickness of the pylons, unless you remove them of the path of the missiles once launched, is this what you mean?

    The pylons used in Su-57 to launch MRAAM are these (UVKU-50L). They launch the missile to clear the airframe as you suppose:

    Su-57 Stealth Fighter: News #6 - Page 9 3e4e-iittafr4117387

    So, if they could operate half extended, a configuration like this may be possible

    Su-57 Stealth Fighter: News #6 - Page 9 00110

    The two lower-most missiles should be launched first of course, then the pylon may retract and clear the way for the other two.

    Other options exist, though  Razz

    Missiles with surfaces and fins fully foldable, + additional launchers attached to the bay doors hinges like in F-35:

    Su-57 Stealth Fighter: News #6 - Page 9 Weapon10

    The important thing is that there is space. And now even smaller missiles, too, so I would not count on the Su-57 being able to carry only 4 MRAAM for the indefinite future.

    Su-57 Stealth Fighter: News #6 - Page 9 5030010

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    Post  GarryB Tue Jul 28, 2020 8:54 am

    The two lower-most missiles should be launched first of course, then the pylon may retract and clear the way for the other two.

    Not sure I understand what you mean.

    Why would the lower most missiles need their launchers to retract anywhere?

    Even if they did have to... US pylons for the AIM-9X actually poke the missile outside the weapon bay with the weapon bay doors open because AIM-9X is a lock on before launch missile and needs a lock before it can be fired... unlike AMRAAM...

    The thing I was worried about as that if you have four pylons side by side for four R-77 missiles... horizontally staggerd of course to allow them to fit better, then how are you supposed to carry two larger weapons like 1,500kg bombs or Grom glide bombs or Kh-38 or Kh-58 or R-37M two side by side in the same bay...
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    Post  LMFS Tue Jul 28, 2020 12:21 pm

    GarryB wrote:Why would the lower most missiles need their launchers to retract anywhere?

    It is very tight for four missiles with fins like current ones. If they are staggered with two lower and two higher, then you need a thinner pylon and it would be best to retract it after launch of the first two missiles, to improve clearances for the launch of the remaining two. They are launched violently and potentially under manoeuvring and aerodynamic interference so the launching movement will have some tolerances. But it was just a side comment, don't take it too seriously. There are many ways they can do things in the end.

    Even if they did have to... US pylons for the AIM-9X actually poke the missile outside the weapon bay with the weapon bay doors open because AIM-9X is a lock on before launch missile and needs a lock before it can be fired... unlike AMRAAM...

    Yeah, pretty much like the side bays for the Su-57Su-57 Stealth Fighter: News #6 - Page 9 Lat_0310

    The thing I was worried about as that if you have four pylons side by side for four R-77 missiles... horizontally staggerd of course to allow them to fit better, then how are you supposed to carry two larger weapons like  1,500kg bombs or Grom glide bombs or Kh-38 or Kh-58 or R-37M two side by side in the same bay...

    You would need to have the provisions (anchoring points + connections) for several pylon layouts. You may also combine them in the plane, one bay carrying the A2A load and the A2G. BTW by now of those weapons you mention the 1500 kg bombs and R-37M are not fit for internal carriage from what we know. Like 10-15 years ago there was a lot of info about this, then suddenly all those sources dried up and we have been left wondering what happened to all those weapons that were being developed, izd. 180PD, izd. 810 etc etc.

    http://take-off.ru/pdf/05_2006.pdf

    I guess the development continued, Obnosov continues to talk about big numbers of weapons being developed for internal carriage but until now they have not released any info that allows to understand if they are going to increase the AAM load in the internal bays. Interestingly, they are not withholding so much information related to the bigger A2G weapons that can be carried in the basic pylon configuration that was know since it appeared already in the Su-47.
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    Post  GarryB Wed Jul 29, 2020 5:52 am

    You really don't want to have a situation where you have to replace weapon pylons for different weapon loads... that would be very clumsy...

    One idea I did have was a cheap and simple short pylon for external weapon carriage that was a one shot pnuematic system that threw the missile downwards and also detached from the wing at the same time so instead of being an arm to throw the missile away from the plane it was more like a leg kicking away from the aircraft and then detaching from the missile.

    The purpose was so that the short, almost conformal pylon came attached to the missile and when fitted to the stealthy aircraft it would hold the missile close to the wing in a semi conformal shell that blended in aerodynamically and in terms of radar return performance minimised the RCS of the external weapon.

    Obviously not as good as internal carriage... but enables oversized weapons to be carried with minimal effect on drag and RCS and could also be adapted to conventional fighters replacing standard wing pylons and reducing drag and RCS too.

    When launched the entire portion is ejected leaving very little behind effectively making it a clean aircraft...

    It might be used with very long range cruise missiles or long range heavy air to air or air to ground missiles... once launched the aircraft will still have full internal weapons and be fully stealthy without wing pylons increasing RCS...

    They have already said they are looking at upgraded medium range missiles with different fin arrangements... why bother except to increase internal capacity?

    The plane was to have all new missiles for the new Stealthy fighters designed specifically for anti stealth fighter use... so passive radar and IIR are likely types of guidance with two way datalinks... and greatly extended flight range.

    Launching an Iskander from a MIG-31 effectively quadrupled its range from 500km to 2,000km.

    Similar improvements in performance could be anticipated from air launched S-400 and S-500 missiles from a MiG-31... perhaps double the ground launched missile range from an Su-57... so 800km and 1,200km for the long range S-400 and S-500 missiles...

    The new R-77M is supposed to have a second stage fuel supply so in terminal attack phase it has a powered rocket motor... with full TVC that means better manouver performance than any conventional control surface could achieve... which means absolutely minimal external surfaces except perhaps narrow strakes for body lift while coasting along at high altitude on a lofted flight path... which is ideal for fitting lots of missiles internally...
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    Post  miketheterrible Wed Jul 29, 2020 5:57 am

    Khinzal isn't a direct 1-1 with Iskander. So firing from a MiG didn't quadrupal range alone.
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    Post  GarryB Wed Jul 29, 2020 6:15 am

    With all the missiles being thrown clear of the bay by powered arm actuators the missiles can be located much closer together because there is less risk of them bumping into other missiles stored there... the stacking means anything that could get in the way will be above the missile so when launched downwards there is no chance of a collision on launch...

    The R-77 was designed for internal carriage in the late 1980s... its rear grid fins were always designed to fold forward against the body.

    I was always surprised they didn't simply attach a second stage booster rocket stage to it that had simple triangle low drag fins in line with where the grid fins flip back and attach to with a simple aerodynamic fairing over the folded grid fins so it is all smooth and aerodynamic.

    On launch the missile is thrown down by the pylon arm and the solid rocket booster lights up and accelerates the missile away... the missile has control points for the rear grid fins exposed when they are folded forward so when they are folded forward small triangular fins on the solid rocket booster can be inserted an controlled by the missile to fly to the interception point. When the solid rocket booster is expended, or as the missile gets close to the target the solid rocket booster can be jettisoned and the grid fins flip out and take control of steering the missile as the missiles main rocket motor lights up...

    If it is a long way to the target the solid rocket booster could be jettisoned when spent but the fins kept while it coasts along... as the speed bleeds down the fins get ejected and grid fin flip into place and the main solid rocket motor of the missile lights up like it has just been launched from an aircraft... ready to chase down and kill planes and other targets.


    Khinzal isn't a direct 1-1 with Iskander. So firing from a MiG didn't quadrupal range alone.

    They didn't really have enough time to make that many changes to it.

    If you think i am exaggerating have a look earlier in this thread... or it might be in the MiG-35 thread where LMFS posted a chart showing range performance for the R-77. Effectively the range performance looks like a mushroom cloud... when launched at low altitude the missile range is very short... 20-30km, while the same missile launched from higher altitude can reach 80km or more... that is because of the altitude and the aircraft speed.

    The performance of a solid rocket weapon is dictated by the altitude it can get to and the horizontal speed it can achieve which directly translate into range.

    At low altitude very few rockets can actually move very fast... there are lots of powerful rockets that move at very high speed but not many of them work at sea level... so even a mach 5 missile launched at sea level at a target at sea level will not get to mach 5 which dramatically reduces the range it can reach... it is like taking the worlds fastest sports car and driving in first gear only.

    Jet powered aircraft climb to medium altitude because they can achieve higher flight speeds in the thinner colder air... a jet powered aircraft will use a higher throttle setting to climb to altitude but once there it throttles back to reduce fuel consumption. At a given height a missile or aircraft shape will travel at a top speed... extra thrust will not change that very much so running around at top thrust like a rocket does wastes fuel.

    Lifting a rocket to high altitude and accelerating it to high speed means the amount of work it needs to do is greatly reduced... at high altitude and already moving at high speed means all its thrust can go into getting higher and faster which both translate into much better range.

    Instead of trying to overcome the weight of the missile and lift it up vertically and accelerate it to as high a speed and altitude as it can manage to then roll on its side and accelerate further towards its target it just needs to accelerate and climb further... instead of mach 6 or 7 it will be moving at mach 9 or 10 for more of its rocket motor burn time.
    The extra length wont be an issue for Su-35s and MiG-35s and Su-30s, but external carriage would be needed for Su-57.
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    Post  miketheterrible Wed Jul 29, 2020 6:21 am

    Iskander been around for more then a decade. They had enough time.
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    Post  owais.usmani Wed Jul 29, 2020 10:40 am

    The easiest way for them to clear up all the confusion is to stack up as many missiles as possible in those internal bays and then do a fly by over the Red Square with those bay doors open, just like the Chinese did with their stealth plane. Very Happy
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    Post  miketheterrible Wed Jul 29, 2020 3:05 pm

    They don't care what internet quasi experts think regarding the bay doors. We just have a glimpse from when Su-57 was tested in Syria. That's about it. China is doing what it can to try to get domestic patriotism up with their crappy J-20 because otherwise, they are known to make garbage equipment and knockoffs.
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    Post  Isos Wed Jul 29, 2020 4:48 pm

    Su-57 Stealth Fighter: News #6 - Page 9 Eegoh010

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    Post  LMFS Wed Jul 29, 2020 5:09 pm

    GarryB wrote:You really don't want to have a situation where you have to replace weapon pylons for different weapon loads... that would be very clumsy...

    In the Su-57 there are already two different internal pylons, UVKU-50L for loads up to 300 kg and UVKU-50U up to 700 kg. And externally happens the same, plus you will need to install additional adapters for some weapons. What is the complexity, four screws and a connector? I haven't done it myself, I ask honestly.

    Obviously not as good as internal carriage... but enables oversized weapons to be carried with minimal effect on drag and RCS and could also be adapted to conventional fighters replacing standard wing pylons and reducing drag and RCS too.

    Conformal carriage on the wings is not something I have seen, but in the fuselage indeed it makes sense... I think we will see many developments, as the need to carry weapons increases but not everything can be taken in the bays

    When launched the entire portion is ejected leaving very little behind effectively making it a clean aircraft...

    Then it should be very cheap, but that and low RCS do not combine well. It should be very well attached (continuity) to the wing or fuselage.

    They have already said they are looking at upgraded medium range missiles with different fin arrangements... why bother except to increase internal capacity?

    For better aerodynamics too.

    The plane was to have all new missiles for the new Stealthy fighters designed specifically for anti stealth fighter use... so passive radar and IIR are likely types of guidance with two way datalinks... and greatly extended flight range.

    Apparently PL-15 has dual seeker (ARH+IR), that is expensive and big, makes sense for very long range missiles. Jamming resistance is an issue we often overlook but can have biggest relevance. In terms of fighting against stealth fighters, what is the problem of current approach? Send the missile to the place where the plane is and let it do the fine tracking when it is very close to the target.

    The new R-77M is supposed to have a second stage fuel supply so in terminal attack phase it has a powered rocket motor... with full TVC that means better manouver performance than any conventional control surface could achieve... which means absolutely minimal external surfaces except perhaps narrow strakes for body lift while coasting along at high altitude on a lofted flight path... which is ideal for fitting lots of missiles internally...

    They were planning to use gas dynamics even in short range missiles (izd. 300). Izd. 180 supposed to have stop capability for the two-pulse rocket engine.
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    Post  LMFS Wed Jul 29, 2020 5:22 pm

    Isos wrote:Su-57 Stealth Fighter: News #6 - Page 9 Eegoh010

    What is that supposed to be? Any news about the serial units?

    BTW, best view of the intakes and ducts yet...  thumbsup

    miketheterrible wrote:They don't care what internet quasi experts think regarding the bay doors.

    Agreed, the less the West knows, the better. Sukhoi guys are not paid based on what Yotube trolls say about the PAK-FA...
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    Post  Isos Wed Jul 29, 2020 5:43 pm

    What is that supposed to be? Any news about the serial units?

    BTW, best view of the intakes and ducts yet... thumbsup

    Fresh picture of a serial su-57. They have no issues with the weapon bays if they build them lol1 .
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    Post  LMFS Wed Jul 29, 2020 6:30 pm

    Isos wrote:Fresh picture of a serial su-57. They have no issues with the weapon bays if they build them lol1 .

    It comes from an article dealing with the set-up of the serial production line of the Su-57:

    http://www.up-pro.ru/library/production_management/systems/sozdat-potochnuyu-liniyu.html

    Su-57 Stealth Fighter: News #6 - Page 9 02

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    Post  GarryB Thu Jul 30, 2020 1:52 pm

    Iskander been around for more then a decade. They had enough time.

    We have no idea how long they worked on the design to change it to make it launch-able from an aircraft... but just looking at it it is not a complete redesign.

    The easiest way for them to clear up all the confusion is to stack up as many missiles as possible in those internal bays and then do a fly by over the Red Square with those bay doors open, just like the Chinese did with their stealth plane.

    The problem there is that the new slimline missiles for internal carriage have not been revealed yet.

    In the early 1990s they showed models of the "next gen" AAMs and they were just white tubes with few external fins or strakes or control surfaces... but they were for internal carriage so that is no surprise.

    They looked like missiles before they had their wings and fins attached a bit like a clothes mannequin... but I suspect lack of limbs is a feature of the missiles rather than an indication they hadn't decided on a configuration yet...

    They don't care what internet quasi experts think regarding the bay doors. We just have a glimpse from when Su-57 was tested in Syria. That's about it. China is doing what it can to try to get domestic patriotism up with their crappy J-20 because otherwise, they are known to make garbage equipment and knockoffs.

    It is simply not in their interests to give away any information at all that could be useful to enemies and rivals.

    Knowing how many and what types of weapons it can carry will effect planning and tactics.

    Missiles don't have 100% kill rates so for instance knowing how many self defence missiles an Su-57 can carry would give an enemy an indication of how many bare minimum missiles would need to be fired at it to assure taking it down... and even then margins will differ based on EW performance etc etc.

    In the Su-57 there are already two different internal pylons, UVKU-50L for loads up to 300 kg and UVKU-50U up to 700 kg. And externally happens the same, plus you will need to install additional adapters for some weapons. What is the complexity, four screws and a connector? I haven't done it myself, I ask honestly.

    I am thinking more in terms of logistics... a forward deployed unit has all the missiles it needs but has to wait for missile adapters to be sent from another airfield because without them they can't be attached to the aircraft.

    Conformal carriage on the wings is not something I have seen, but in the fuselage indeed it makes sense... I think we will see many developments, as the need to carry weapons increases but not everything can be taken in the bays

    There was the idea of a large under-fuselage pod that was primarily an external fuel pod but also contained internal bays to store weapons without adding to drag too much... it was before stealth was a concern of course so RCS wasn't a factor... high speed flight and drag were the considerations... something like a rocket pod with fuel storage included with simple wiring so it could be jettisoned when empty of fuel and rockets...

    Then it should be very cheap, but that and low RCS do not combine well. It should be very well attached (continuity) to the wing or fuselage.

    Thinking more drag than RCS as it would be used for very long range weapons too big to carry internally so it should be launched early in the mission anyway... and could include external fuel tanks... perhaps even a disposable active jammer that can be dropped when empty of fuel so enemy missiles will chase it...

    For better aerodynamics too.

    No. For lower cruise drag. For terminal manouver performance small triangular wings means worse aerodynamics...


    Apparently PL-15 has dual seeker (ARH+IR), that is expensive and big, makes sense for very long range missiles. Jamming resistance is an issue we often overlook but can have biggest relevance. In terms of fighting against stealth fighters, what is the problem of current approach? Send the missile to the place where the plane is and let it do the fine tracking when it is very close to the target.

    When it starts scanning it immediately alerts all potential targets in the area that an attack is in progress...

    They were planning to use gas dynamics even in short range missiles (izd. 300). Izd. 180 supposed to have stop capability for the two-pulse rocket engine.

    Perhaps the work on the ramjet R-77PD stopped because the replacement for the Izd 180 is going to use scramjet propulsion.... Izd 270.
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    Post  Isos Thu Jul 30, 2020 2:00 pm

    Apparently PL-15 has dual seeker (ARH+IR), that is expensive and big, makes sense for very long range missiles. Jamming resistance is an issue we often overlook but can have biggest relevance. In terms of fighting against stealth fighters, what is the problem of current approach? Send the missile to the place where the plane is and let it do the fine tracking when it is very close to the target.

    The missile would go too fast to spend time looking for a target but too slow to manoeuvre a lot.

    ARH missile are not different from SARH missiles. They need constant data about target position/course/speed so that when it goes active it goes in the right direction and can look at the target directly without looking for it.

    Sending the missile somewhere and let it do all by itself would drop the Pk, which is already low, to 0 and could even go in the negative which means it could attack friendly aircraft as it doesn't have inbuild IFF.
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    Post  LMFS Thu Jul 30, 2020 4:02 pm

    GarryB wrote:Knowing how many and what types of weapons it can carry will effect planning and tactics.

    Exactly, that is very concrete information for force planing and tactics that they will instead have to estimate. And given Russians don't say a peep about the AAMs since almost a decade either, US planers could incur into gross calculation errors. VKS is being too careful with this particular issue not to think they are up to something, me thinks...

    I am thinking more in terms of logistics... a forward deployed unit has all the missiles it needs but has to wait for missile adapters to be sent from another airfield because without them they can't be attached to the aircraft.

    There is a number of accessories and supporting equipment you need to service and operate the planes, it would just make sense these different pylons are part of that. As said, internal pylons are already different depending on the weapons carried so this is necessary already.

    There was the idea of a large under-fuselage pod that was primarily an external fuel pod but also contained internal bays to store weapons without adding to drag too much... it was before stealth was a concern of course so RCS wasn't a factor... high speed flight and drag were the considerations... something like a rocket pod with fuel storage included with simple wiring so it could be jettisoned when empty of fuel and rockets...

    Yeah, RCS is commonly discussed as the main driver for this but drag is a huge issue as well. The F-15 had some proposals like the one you mention that would fit in the CFTs, they were not jettisonable though. The installation is complex and those things are very expensive.

    Thinking more drag than RCS as it would be used for very long range weapons too big to carry internally so it should be launched early in the mission anyway... and could include external fuel tanks... perhaps even a disposable active jammer that can be dropped when empty of fuel so enemy missiles will chase it...

    In therms of drag it makes sense to include provisions in the jet's fuselage to carry conformal AAMs like Eurofighter or F-15 (with drag index zero or negligible), for bigger weapons the examples of Kh-22 and R-33 still apply IMHO. To completely enclose a missile like Kinzhal inside a container would make it big, complex and heavy.

    No. For lower cruise drag. For terminal manouver performance small triangular wings means worse aerodynamics...

    Well, that is what I meant, better aero (less drag) so the missile's range is increased. I don't know whether you can say the lattice fins are "better" for manoeuvring, I read they were better at lower speeds but not that good at high AoA...

    When it starts scanning it immediately alerts all potential targets in the area that an attack is in progress...

    ...and 5 seconds after it hits the target... without previous notice the pilot barely has the time to realize he is under attack and start to get the bank angle needed to turn.

    Perhaps the work on the ramjet R-77PD stopped because the replacement for the Izd 180 is going to use scramjet propulsion.... Izd 270.

    Maybe, but I don't think it is necessary, because ramjet is still more than fast enough and much more simple, plus all the R&D work done is hardly going to be just thrown in the trash bin. Scramjet for much bigger, substrategic missiles is still a technical challenge (not commissioned) and not cheap. I have not heard about that izd 270 missile, do you have more info on it?

    Isos wrote:ARH missile are not different from SARH missiles. They need constant data about target position/course/speed so that when it goes active it goes in the right direction and can look at the target directly without looking for it.

    The big difference is that missile guidance per data link is done on narrow angles and does not need to alert the target, while semiactive guidance needs to illuminate and alert it, spoiling the surprise and making its success chances minimal...
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    Post  Isos Thu Jul 30, 2020 4:41 pm

    The big difference is that missile guidance per data link is done on narrow angles and does not need to alert the target, while semiactive guidance needs to illuminate and alert it, spoiling the surprise and making its success chances minimal...

    Yes that's an advantage until they find out a way to detect the launch.

    Also automatic jammers and MAWS + automatic chaffs will work better on such missiles, specially at the moment when the missile activates its radar and tries to find the target and can lock on chaffs.
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    Post  GarryB Fri Jul 31, 2020 7:45 am

    ARH missile are not different from SARH missiles. They need constant data about target position/course/speed so that when it goes active it goes in the right direction and can look at the target directly without looking for it.

    An ARH might not arrive to its intercept point to find its primary target directly ahead of it... so it generally needs a scan of the airspace in front of it to precisely locate and lock its target... we are not talking a 180 degree scan like a printer from the 1980s printing out an A4 sized photo... just a single sweep scan and lock on to the object that looks most like the target.

    Sending the missile somewhere and let it do all by itself would drop the Pk, which is already low, to 0 and could even go in the negative which means it could attack friendly aircraft as it doesn't have inbuild IFF.

    MMW radar and IIR should be able to determine the basic layout and shape of the target so much of the time that alone could be used to avoid friendly fire, but why not include IFF as well?


    Yeah, RCS is commonly discussed as the main driver for this but drag is a huge issue as well. The F-15 had some proposals like the one you mention that would fit in the CFTs, they were not jettisonable though. The installation is complex and those things are very expensive.

    I would suggest if anyone can take something the west has tried to do and given up on because it was too complex and expensive, then the Russians could probably do it... tank gun launched missiles, rocket powered torpedoes, even fighter jet planes that can operate from ships without steam or EM catapults... without needing to be VSTOL types...

    I mean look at the TVC used in the R-73 missile... it looks agricultural... but it is simple and it works... and has been working for 40 odd years... the same with airburst 40mm grenades... the American equivalent uses a laser range finder and ballistic computer on the grenade launcher and a super accurate piece of swiss electronics in each grenade making each grenade rather expensive... but in terms of performance a grenade exploding at your feet gives you extensive injuries in your legs and lower body, but an airburst grenade gives you head and upper chest injuries that are far more critical... so the extreme cost could be said to be worth it. The Soviets in the late 1970s simply added a small charge in the nose fuse of the grenade with a short exploding fuse to the main charge... on impact with the ground the small charge blows the grenade to a height of 1.5-2m where the fuse sets off the main charge... in your face... the two explosions are near simultaneous... there is no time to dodge or take cover.... cheap and simple and in mass production for 40 years... the grenade launchers clip on to AK rifle types like a bayonet attachment... and have both direct and indirect sights.

    In therms of drag it makes sense to include provisions in the jet's fuselage to carry conformal AAMs like Eurofighter or F-15 (with drag index zero or negligible), for bigger weapons the examples of Kh-22 and R-33 still apply IMHO. To completely enclose a missile like Kinzhal inside a container would make it big, complex and heavy.

    I seem to remember it was used on the American Hustler supersonic bomber... a large object that looked like an external fuel tank that actually carried fuel and bombs in a lower drag pod type set up... I believe later pods consisted of a two part system where the fuel portion could be jettisonned separately so the aircraft could take off with nuclear bombs and fuel in a big ventral tank, but when the fuel was used up it could be dropped, but the smaller bomb section could be retained and carried to target.

    Those images of vertically fired weapons for bombers suggest another option could be to fit upward launching pylons in their own weapon bays on the upper surface of the wing and fuselage... a crane could be used to load them and the arm launcher throwing them clear of the aircraft could be used as normal.

    When not used for bombs or missiles it could hold internal fuel cells so the internal volume is not wasted.

    Well, that is what I meant, better aero (less drag) so the missile's range is increased. I don't know whether you can say the lattice fins are "better" for manoeuvring, I read they were better at lower speeds but not that good at high AoA...

    Actually the opposite... their enormous surface area gives them much more force while at the same time making them effective in creating turning force at much higher angles of attack when conventional surfaces would be stalling an essentially just generating drag.

    Such lattice surfaces are used on some of their ballistic missiles so I would suggest where ever you got the idea they were only useful at low speeds might want to check their information. Perhaps confusion  with Biplane surfaces perhaps... but the grid fins have thin high speed aerofoils, not thick chunky subsonic profiles...

    ...and 5 seconds after it hits the target... without previous notice the pilot barely has the time to realize he is under attack and start to get the bank angle needed to turn.

    Depends on the missile... medium range missiles can detect fighter targets out to 20-30km and heavy missiles like the R-37M might detect an AWACS aircraft at 50-60km... which is rather more than 5 seconds to target... though of course an AWACS pilot wont be looping the loop to evade the incoming missile...


    Maybe, but I don't think it is necessary, because ramjet is still more than fast enough and much more simple, plus all the R&D work done is hardly going to be just thrown in the trash bin.

    A ramjet is inferior technology with had speed limitations that means its flight performance is effectively a long burning solid fuel rocket... a scramjet is the same technology with a more sophisticated fuel burning section that offers the potential for much higher flight speeds and greatly increased performance... and they have been working on scramjet motors for the last 30 years... a ramjet powered R-77 would be a scaled down KH-31 effectively... which has been in service for 30 odd years... the R&D work to double the speed might mean new materials but other new weapons are going to need those too anyway... it is not like these are systems that have no other application... I would suggest a scramjet powered missile would be a useful addition to most SAM batteries... S-350, S-400, even S-500 for super long range 1,200km range interception of targets inside the atmosphere...

    Scramjet for much bigger, substrategic missiles is still a technical challenge (not commissioned) and not cheap

    Zircon will be the first, but certainly not the only...

    I have not heard about that izd 270 missile, do you have more info on it?

    Just a paragraph in Butowskis "Russias air launched weapons" printed in 2017.

    In the section on the R-77 family it ends with:

    For several years, Vympel has been designing a next generation Izdeliye 270 medium and extended range AAM, which is to replace the R-77M in the future. No (further) information about it is known.


    The big difference is that missile guidance per data link is done on narrow angles and does not need to alert the target, while semiactive guidance needs to illuminate and alert it, spoiling the surprise and making its success chances minimal...

    If the missile is heading toward the target then directing data at the missile is also directing data at the target... and for the Russians having wing mounted AESA radar antenna modules in your wings and the HATO datalink operating in L band might be a problem in terms of stealth.

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    Post  LMFS Fri Jul 31, 2020 1:36 pm

    GarryB wrote:I would suggest if anyone can take something the west has tried to do and given up on because it was too complex and expensive, then the Russians could probably do it...

    The trick with the grenades is a nice one indeed... I guess US MIC simply sees more profit in doing things differently and not setting the bar too high for themselves, so they can profit all along by selling worse products, with more profit and less effort. And since they are measured by their ability to "generate value" for their shareholders (to rip-off the federal budget, in layman terms), in fact they are encouraged to further act like that. The problem is that sustaining such approach for decades spoils the whole industry both in ethical and technological sense... when you want to backtrack and produce real military value at reasonable price, it is not so easy anymore..

    I seem to remember it was used on the American Hustler supersonic bomber...

    Didn't knew that one  thumbsup

    Those images of vertically fired weapons for bombers suggest another option could be to fit upward launching pylons in their own weapon bays on the upper surface of the wing and fuselage... a crane could be used to load them and the arm launcher throwing them clear of the aircraft could be used as normal.

    I think upper side release is limited to certain kinds of carriers and weapons... under turning you would end up hitting the released missile yourself or making simply impossible the release (under how many g's should the release work?)

    Actually the opposite... their enormous surface area gives them much more force while at the same time making them effective in creating turning force at much higher angles of attack when conventional surfaces would be stalling an essentially just generating drag.

    You seem to be right regarding them being more resistant to stall at high AoA, even when high aspect ratio airfoils like those used on them stall at lower AoA... I am researching those lattice fins, I will come back to the issue when I am done. BTW their name is Belotserkovskiy’s Grid Fin and they were not invented by Elon Musk, contrary to what people seem to think... Very Happy

    Such lattice surfaces are used on some of their ballistic missiles so I would suggest where ever you got the idea they were only useful at low speeds might want to check their information. Perhaps confusion  with Biplane surfaces perhaps... but the grid fins have thin high speed aerofoils, not thick chunky subsonic profiles...

    There are a number of advantages related to low hinge moments at high speeds which seems to help with the actuators, plus them being foldable. They seem to generate more drag though, and block the flow in the transonic region. But as said above, let me check this in detail so we understand properly the reasons for them being used.

    A ramjet is inferior technology with had speed limitations that means its flight performance is effectively a long burning solid fuel rocket... a scramjet is the same technology with a more sophisticated fuel burning section that offers the potential for much higher flight speeds and greatly increased performance... and they have been working on scramjet motors for the last 30 years... a ramjet powered R-77 would be a scaled down KH-31 effectively... which has been in service for 30 odd years... the R&D work to double the speed might mean new materials but other new weapons are going to need those too anyway... it is not like these are systems that have no other application... I would suggest a scramjet powered missile would be a useful addition to most SAM batteries... S-350, S-400, even S-500 for super long range 1,200km range interception of targets inside the atmosphere...

    Yeah, why settle for 5 M when you can go to 10 M... my only comment is that MRAAMs are barely 20 cm diameter, designed for numbers and by now considerably less complex than bigger missiles. It may change though, if it is understood that making them more complex and expensive can significantly increase their pk. Without forgetting the number of technologies being added to the mix right now in terms of self defence of the target and so on... not easy to know exactly how the race will evolve in coming years.

    Zircon will be the first, but certainly not the only...

    That is for sure

    Just a paragraph in Butowskis "Russias air launched weapons" printed in 2017.

    Ok thanks

    If the missile is heading toward the target then directing data at the missile is also directing data at the target... and for the Russians having wing mounted AESA radar antenna modules in your wings and the HATO datalink operating in L band might be a problem in terms of stealth.

    Depends on the shot, but normally the missile will be lofting and not be in direct line to the target
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    Post  GarryB Sat Aug 01, 2020 7:25 am

    The trick with the grenades is a nice one indeed... I guess US MIC simply sees more profit in doing things differently and not setting the bar too high for themselves, so they can profit all along by selling worse products, with more profit and less effort.

    Ironically it was the swiss company that makes the precision timers that would have benefited most because soldiers in the field will use them for all sorts of targets.

    The basic idea of the Russian grenade design basically emulates the WWII German bounding mines which basically did the same thing... simply and effectively allowing them to be widely used, which makes them much more effective than an expensive system.

    The main difference of course is that the American system can be used against air targets like a hovering drone that a Russian grenade would just fly past... but for most of the time you fire rifle grenades at ground targets... so it is certainly good enough...

    when you want to backtrack and produce real military value at reasonable price, it is not so easy anymore..

    At some stage they will realise that nothing is for free and just buying the cheapest option is not a good way to run a military or an economy because cheapest is always offshore and will destroy your economy and make you dependent on imports... which is what it is doing.

    Didn't knew that one

    It didn't last long... for a period there was the belief that flying fast would reduce engagement range to a point where you could weave through the defences and always get through. Flying high and fast meant only the biggest SAMs could get you and they were easy to plot on a map... so you could plan well ahead of time a safe flight path.

    Problem for them is that they invested a lot in missiles and put them everywhere and started making them quite mobile... pretty soon it became obvious to get through you needed to go low and big turbojets are not great at flying low and fast so they went from the Hustler to the Aardvark... F-111... which started life as a carrier based fighter but was found to be too heavy... so they made it a land based strike aircraft... the radar they developed for it and the big AAMs it was going to carry eventually were used on the F-14 and the F-14A kept the same turbofan engines of the F-111...

    I think upper side release is limited to certain kinds of carriers and weapons... under turning you would end up hitting the released missile yourself or making simply impossible the release (under how many g's should the release work?)

    I would think the main problems pushing weapons up into the slipstream going over the aircraft would be with unpowered weapons like bombs... but small parachute retard devices should solve that. The pylons throwing the weapons down might need a bit more power throwing things up, but just like weapons launched downwards need to be designed not to immediately pull and hard climb into the bottom of the aircraft, weapons launched upwards would need to accelerate forward before starting any dive... ideally weapons launched upwards should be the sort of weapons that benefit from altitude.... like most AAMs so a short climb clear of the aircraft and then a dive down on the target could be part of their design.

    Bombs could be stored vertically so when they are launched upwards they are not in an aerodynamicaly efficient orientation meaning the slipstream would drag them back like they were fitted with a parachute without needing one... the problem there would be that they would probably end up tumbling which would make accuracy fairly random... perhaps bombs released upwards should only be glide bombs or guided bombs with wings and control surfaces to stabilise their flight and take them clear of the aircraft safely...

    BTW their name is Belotserkovskiy’s Grid Fin and they were not invented by Elon Musk, contrary to what people seem to think...

    I seem to remember OKA missiles had them... and Tochka missiles have them too... Smile


    Depends on the shot, but normally the missile will be lofting and not be in direct line to the target

    The question is... how narrow are L band beams... the beams used for SARH are described as being pencil beams but how narrow are the beams sent to ARH AAMs in flight... there is no need for them to be super narrow because that would only mean it is rather more difficult to communicate with the missile because now you have to precisely track it too...

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    Post  LMFS Sat Aug 01, 2020 1:30 pm

    GarryB wrote:I would think the main problems pushing weapons up into the slipstream going over the aircraft would be with unpowered weapons like bombs...

    But what is the advantage of pushing the bombs over the plane instead of doing it with the help of gravity? I mean, for some layouts it may help, but normally it just adds something else that can go wrong.

    I seem to remember OKA missiles had them... and Tochka missiles have them too...   Smile

    Yes, and many others too, it is a Russian invention.

    The question is... how narrow are L band beams... the beams used for SARH are described as being pencil beams but how narrow are the beams sent to ARH AAMs in flight... there is no need for them to be super narrow because that would only mean it is rather more difficult to communicate with the missile because now you have to precisely track it too...

    Command beam over the radar is a couple degrees wide, I would need to look into L band links...

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