PAK DP prospective long-range interceptor

Borschty wrote:Issue with designing the next generation if interceptors is the power-plant and metallurgy (For the aircraft's frame) for above mach 3. Turbojet can only produce so much power before they become irrelevant (Due to RPM limitations). Some have said it'll most likely use Air-Turbo Ramjets/ Pure Ramjet but as we know, ramjets consume a lot of fuel.

Apparently speed limitation in both MiG-25 and 31 came from engine inlet temperature not airframe (New alu alloys are available now for the airframe BTW). With new materials (rumours have it that TIT in izd. 30 reaches above 1800°C) maybe the same basic design of old engines could be stretched above 3 M.
If they want an aircraft clearly above the limits of the turbojets then they would need to design a brand new engine and we know that takes longer than designing a plane. Either they have something completely secret or the MiG-41 will enter service around 2040 or it is not going to be that fast, I would say

MoD can be presented with different options between conservative evolution of MiG-31 and sci-fi project with all the options in between... services normally select proposals that can be implemented with the technology at hand and in concrete, realistic steps rather than pipe dreams, but I admit I have no clue where the optimum will be, concrete schedule, level of future threats and doctrine to deal with them are crucial to make an estimation and I have no clear view of any of those in the 2030-2040 horizon, there are so many things happening in regards of technology that it is quite difficult to anticipate events.

2) MiG-31 is very easy to be best since it the only one in its class

I agree it is alone in its class, but only because it is so superior from any foreign analog.

The US equivalent is the F-15C... which is slower and with much shorter ranged missiles.

The European equivalents would be Typhoon and Rafale, which are also much slower and with much shorter ranged missiles.

Every air force needs an interceptor... the US Navy equivalent is the F-18 which is also slower and with much shorter ranged missiles too....

Same that's happening with Tupolev, waiting for PAK-DA they will produce updated versions of Tu-22 and Tu-122.

I don't think they would put MiG-31s into production as a stopgap for a new interceptor... more likely they will continue to upgrade existing MiG-31 airframes... I think the MiG-41 will be a blank sheet of paper new design optimised for much higher speeds, and likely internal weapons carriage just to reduce drag...

New long range AAMs are being developed for the PAK FA specifically for internal carriage and I think they will also be used on the MiG-41 too.

Issue with designing the next generation if interceptors is the power-plant and metallurgy (For the aircraft's frame) for above mach 3. Turbojet can only produce so much power before they become irrelevant (Due to RPM limitations). Some have said it'll most likely use Air-Turbo Ramjets/ Pure Ramjet but as we know, ramjets consume a lot of fuel.

If the speed required is mach 4.2 then a ramjet would be a requirement... but there is no reason why a combined turbojet/ramjet arrangement could not be used like they used on the SR-71.

Very simply the bypass air can be used to power a ramjet arrangement so once the turbojet engines get you up to supersonic speeds then the bypass air is increased and fuel added and burned like a ramjet to generate thrust... as you increase in speed the air going through the turbojets is reduced to zero and they are shut down, while the air going through the ramjet bypass flow gets more fuel added and all the thrust for flight is provided by the ramjet... which is very simple and has no moving parts... the only limitation would be airflow to allow subsonic combustion to generate the thrust... but a scramjet arrangement could deal with that too.

LMFS wrote:
Apparently speed limitation in both MiG-25 and 31 came from engine inlet temperature not airframe. With new materials (rumours have it that TIT in izd. 30 reaches above 1800°C) maybe the same basic design of old engines could be stretched above 3 M.
If they want an aircraft clearly above the limits of the turbojets then they would need to design a brand new engine and we know that takes longer than designing a plane. Either they have something completely secret or the MiG-41 will enter service around 2040 or it is not going to be that fast, I would say

MiG-31 service life is coming to an end. They have do something anyway. Basic engines can be stretched till 3,2 Ma already.  

MoD can be presented with different options between conservative evolution of MiG-31 and sci-fi project with all the options in between... services normally select proposals that can be implemented with the technology at hand and in concrete, realistic steps rather than pipe dreams, but I admit I have no clue where the optimum will be, concrete schedule, level of future threats and doctrine to deal with them are crucial to make an estimation and I have no clear view of any of those in the 2030-2040 horizon, there are so many things happening in regards of technology that it is quite difficult to anticipate events.

There is not that bad with future is you look around:

1) US tried for SR-72 combined turbojet + scramjet but wanted 6Ma. Russians say  up-to 4,3 Ma ~ 4,600 km/h )





2) other option is PDE. Russians already were testing in 2017 (check RG article). PDE accordign to Russian wiki can be effectively applied from subsonic to 4-5Ma (compare with MiG-41 envisaged speed...) .If you know how to control explosions then PDE is fairly primitive. No turbines and virtually no moving parts either...

My bet is on PDE.



3) SABRE type but IMHO unlikely.

GarryB wrote:

2) MiG-31 is very easy to be best since it the only one in its class

I agree it is alone in its class, but only because it is so superior from any foreign analog.
The US equivalent is the F-15C... which is slower and with much shorter ranged missiles.
The European equivalents would be Typhoon and Rafale, which are also much slower and with much shorter ranged missiles.

Every air force needs an interceptor... the US Navy equivalent is the F-18 which is also slower and with much shorter ranged missiles too....

not every tho needs to fly over arctic over thousand kilometers of  ice desert land.  Nobody tried to approach similar requirements thus MiG-31 is only one in it class. Dont mix Rafale requirements with MiG-31 ones please.

Issue with designing the next generation if interceptors is the power-plant and metallurgy (For the aircraft's frame) for above mach 3. Turbojet can only produce so much power before they become irrelevant (Due to RPM limitations). Some have said it'll most likely use Air-Turbo Ramjets/ Pure Ramjet but as we know, ramjets consume a lot of fuel.

If the speed required is mach 4.2 then a ramjet would be a requirement... but there is no reason why a combined turbojet/ramjet arrangement could not be used like they used on the SR-71.

No, not only. PDE can be also one. Especially that Russians were actively researching this for years.

GunshipDemocracy wrote:Basic engines can be stretched till 3,2 Ma already.

Which ones? As said safe operation limit for both MiG-31 and 25 was 2.83 M, everything above that was at the expenses of engine integrity

1) US tried for SR-72 combined turbojet + scramjet but wanted 6Ma. Russians say  up-to 4,3 Ma ~ 4,600 km/h )

Well this is complex and it aims at a top speed where turbojets cannot help. There has been no official communication about MiG-41 requirements, only hints of no firm value. And they are not indicating such speeds

2) other option is PDE. Russians already were testing in 2017 (check RG article). PDE accordign to Russian wiki can be effectively applied from subsonic to 4-5Ma (compare with MiG-41 envisaged speed...) .If you know how to control explosions then PDE is fairly primitive. No turbines and virtually no moving parts either...

My bet is on PDE.

PDE is valid from subsonic to orbital speed, hence its huge relevance.

From what we know this is only work at experimental level. If they are much more advance than disclosed they could use it but otherwise there is no way you can have this in the series in less than 15-20 years, all going smoothly.

3) SABRE type but IMHO unlikely

This is technology for putting load in orbit and based in hydrogen... don't think this is practical for a tactical interceptor

LMFS wrote:

GunshipDemocracy wrote:Basic engines can be stretched till 3,2 Ma already.

Which ones? As said safe operation limit for both MiG-31 and 25 was 2.83 M, everything above that was at the expenses of engine integrity

Not really, MiG-25 was powered by R-15B-300 and indeed had problems with keeping 3,2 Ma speed.


MiG-31  is powered by Д-30Ф6. There were restrictions but didnt find any info that was referred  to engine.
MiG-31BM: TV Zvezda last year made short vid where MiG tech deputy said that with new canopy glass there are no more restrictions with speed and can fly 3,400km/h
what is 3,2 Ma (by Ma= 295m/s). Before BM upgrade it couldn't stand overheating and was prone to  overheating. Or approaching to 3,400km/h  (TV Zezda described) floating.

There has been no official communication about MiG-41 requirements, only hints of no firm value. And they are not indicating such speeds

There is no solution not complex with any of new fighters. As for speed they already indicated: 4-4,3 Ma (Ilya Tarasenko OAK Board member, CEO MiG) .

2) other option is PDE.  My bet is on PDE.

PDE is valid from subsonic to orbital speed, hence its huge relevance.

From what we know this is only work at experimental level. If they are much more advance than disclosed they could use it but otherwise there is no way you can have this in the series in less than 15-20 years, all going smoothly.

Not sure why do you need 20 years to develop engine known over 70 years. Especially that in 2013 Russians already build full size demonstrator. Not sure why in next 7-10 years they should not be able to move to serial stage?

https://lenta.ru/news/2013/09/24/pulse/

The experimental design bureau Lyulki developed, manufactured and tested a prototype of a pulsating resonator detonation engine with a two-stage combustion of a kerosene-air mixture. According to ITAR-TASS , the average measured engine thrust was about one hundred kilograms, and the duration of continuous operation is more than ten minutes. By the end of this year, the design bureau intends to manufacture and test a full-size pulsating detonation engine.

According to the chief designer of the Lyulka Design Bureau named after Alexander Tarasov, during the tests, the modes of operation characteristic of turbojet and direct-flow engines were modeled. The measured values ​​of specific thrust and specific fuel consumption turned out to be 30-50 percent better than that of conventional jet engines. In the course of the experiments, the new engine was repeatedly switched on and off, as well as thrust control.

On the basis of the conducted research, obtained during the testing of data, as well as circuit design analysis, the Lyulki Design Bureau intends to propose the development of a whole family of pulsating detonation aircraft engines. In particular, engines with a short service life for unmanned aerial vehicles and rockets and aircraft engines with cruising supersonic flight mode can be created.

3) SABRE type but IMHO unlikely

This is technology for putting load in orbit and based in hydrogen... don't think this is practical for a tactical interceptor

[/quote]

Indeed for orbital bomber much more interesting

not every tho needs to fly over arctic over thousand kilometers of ice desert land. Nobody tried to approach similar requirements thus MiG-31 is only one in it class. Dont mix Rafale requirements with MiG-31 ones please.

Ahh, so the Russians use the MiG-31 as an interceptor but the French and the English and Americans and Germans have technology that means interception is not important to them?

The only comparable aircraft to the MiG-31 was the F-14 in terms of missile range and expected performance in terms of intercepting enemy targets at max possible range to increase the safety of the ships it happened to operate from.

In terms of range the F-14 wasn't bad, but it was inferior in terms of speed, though its missile range was excellent it has since been eclipsed by the R-37M.

The French have the Rafale as a naval interceptor and the English have the F-35, while the Americans currently use the F-18 because they expected the Russians to scrap all their Backfires and curl up in a little fetal ball and just do as they are told, while the US consumes all their natural resources...

GarryB wrote:

not every tho needs to fly over arctic over thousand kilometers of  ice desert land.  Nobody tried to approach similar requirements thus MiG-31 is only one in it class. Dont mix Rafale requirements with MiG-31 ones please.

Ahh, so the Russians use the MiG-31 as an interceptor but the French and the English and Americans and Germans have technology that means interception is not important to them?

do you suggest thet there is 1:1 mapping in all categories of equipment? They dont have Iskander SRBM or S-400 either.

The only comparable aircraft to the MiG-31 was the F-14 in terms of missile range and expected performance in terms of intercepting enemy targets at max possible range to increase the safety of the ships it happened to operate from.
In terms of range the F-14 wasn't bad, but it was inferior in terms of speed, though its missile range was excellent it has since been eclipsed by the R-37M.

And you wonder why they scrapped this? not because of technology.  F-14 was to intercept Tu-160 or Tu-22 wanst it? Perhaps because  "Iceman" Kazansky wont fit the cockpit anyore?

The French have the Rafale as a naval interceptor and the English have the F-35, while the Americans currently use the F-18 because they expected the Russians to scrap all their Backfires and curl up in a little fetal ball and just do as they are told, while the US consumes all their natural resources...

That's the sweet life of a vassal and serf. France doesnt have any other fighter so what they were supposed to use? Super Entendard? New Dassault (German financed ;-) can be much better.





Anyway France is vassal but not willing slave as  my country. Which elites are willing to pay US extra for military occupation      

GunshipDemocracy wrote:Not really, MiG-25 was powered by R-15B-300 and indeed had problems with keeping 3,2 Ma speed.

MiG-31  is powered by Д-30Ф6. There were restrictions but didnt find any info that was referred  to engine.
MiG-31BM: TV Zvezda last year made short vid where MiG tech deputy said that with new canopy glass there are no more restrictions with speed and can fly 3,400km/h
what is 3,2 Ma (by Ma= 295m/s). Before BM upgrade it couldn't stand overheating and was prone to  overheating. Or approaching to 3,400km/h  (TV Zezda described) floating.

Yes, now I remember that news too. It is strange then that MiG-25 had no problems with the canopy but the 31 was limited to 2.83 M only because of that and not because of the engines?

There is no solution not complex with any of new fighters. As for speed they already indicated: 4-4,3 Ma (Ilya Tarasenko OAK Board member, CEO MiG) .

Don't try so hard to misunderstand me. By complex I mean two different types of engine in one plane. All that space, weight and complexity is going to be detracted from your range, payload and reliability. I would think a military plane in Russia (no country for hangar-queens) needs to be based on more mature technology. But again, we know essentially nothing consistent from MiG-41, and not in a small part due to the funny statements from Tarasenko and co. (still remembering the "available to series in 2025" part).

Not sure why do you need 20 years to develop engine known over 70 years. Especially that in 2013 Russians already build full size demonstrator. Not sure why in next 7-10 years they should not be able to move to serial stage?

https://lenta.ru/news/2013/09/24/pulse/

Good info thanks. But the immediate question that arises is: why have they been knowing about this engine for 70 years and still no one has managed to take it out of the laboratory and into the serial production? Maybe it is not such an obvious thing? And why is it going to be ready right here right now for the MiG-41? I mean, I would be the first to celebrate if they pull that out, but from laboratory sample to deployment in the Artic with the folks of the VVS there are quite a few maturity steps you know?

As said, unless they are more advanced than what they say, this engine is not going to be ready before 2030 in any way.

Indeed for orbital bomber much more interesting

C'mon, with PDE nobody would need that crappy SABRE

LMFS wrote:
Yes, now I remember that news too. It is strange then that MiG-25 had no problems with the canopy but the 31 was limited to 2.83 M only because of that and not because of the engines?

Funny becsues neither in ru wiki nor in militaryarms ru was nothign about engine problems... There are though other interesting data:
1) MiG-25 was tested by US specialists and they establish thet 3,400kms + could be reached
2) Over Sinai in 70s one time radars recorded MiG-25 flying with 3,600 km/h (I wish to find more sourced about it)
3) Russian pilots ordered to keep innormal regime speed up to 3000km/h (no explanation why, canopy thus could be same reason...)

https://ru.wikipedia.org/wiki/%D0%9C%D0%B8%D0%93-25
https://militaryarms.ru/voennaya-texnika/aviaciya/istrebitel-perexvatchik-mig-25/

There is no solution not complex with any of new fighters. As for speed they already indicated: 4-4,3 Ma (Ilya Tarasenko OAK Board member, CEO MiG) .

Don't try so hard to misunderstand me. By complex I mean two different types of engine in one plane. All that space, weight and complexity is going to be detracted from your range, payload and reliability. I would think a military plane in Russia (no country for hangar-queens) needs to be based on more mature technology. But again, we know essentially nothing consistent from MiG-41, and not in a small part due to the funny statements from Tarasenko and co. (still remembering the "available to series in 2025" part).

1) there is no simple solution. Reliability? so what would you expect a biplane? or perhaps that Su-57 is a simple or not reliable?
2) again I cannot get your range/payload concerns - then you build bigger to have desired payload and range, you dont have any size restrictions do you? compare Su-35 and MiG-31.


3)

(a) from 2013 (where PDE was supposed to be build full size working model) till 2025 is 12 years. Why d you think it take more than 12 years to work our engine? They already have huge experience in high speed frames design. This is rather question of priority (and money supply)

(b) MiG-31BM service life is extended till 2028...

(c) No first about 2025 said general-colonel Viktor Bondaryev in 2016. He stated (in 2015) that R&D is already in full swing and from 2017 development work (2nd stage of Russian R&D nomenclature) should tart so around 2025 interceptor can start to be built.

https://tvzvezda.ru/news/forces/content/201601220803-pcva.htm

Not sure why do you need 20 years to develop engine known over 70 years. Especially that in 2013 Russians already build full size demonstrator. Not sure why in next 7-10 years they should not be able to move to serial stage?

https://lenta.ru/news/2013/09/24/pulse/

Good info thanks. (1) But the immediate question that arises is: why have they been knowing about this engine for 70 years and still no one has managed to take it out of the laboratory and into the serial production? Maybe it is not such an obvious thing? And why is it going to be ready right here right now for the MiG-41? I mean, I would be the first to celebrate if they pull that out, but from laboratory sample to deployment in the Artic with the folks of the VVS (3) there are quite a few maturity steps you know?

(2) As said, unless they are more advanced than what they say, this engine is not going to be ready before 2030 in any way.

(1) Mind nobody before also made hypersonic missiles fly and not burn immediately nor nuclear power source to CMs.
(2) That we dont know and until MiG-41 is made official. Not necessarily with PDE however PDE would solve many things. Still it would be hybrid drive (or as they call it: dual mode)- start with conventional jet engine. Mind dates of replacement MiG-31s is in 11 years...

From Russian sources work on MiG-41 started form 2014. Why in 12 years they could build first flying examples?

(3) yupbut MiG-35 is over matured so it is not always like that ;-)

http://bastion-opk.ru/mig-41/
https://tvzvezda.ru/news/forces/content/201601220803-pcva.htm

Indeed for orbital bomber much more interesting

C'mon, with PDE nobody would need that crappy SABRE

[/quote]

Not sure how much more efficient is for orbital transport is pde vs sabre. Whatever works better ;-)

Hole wrote:Speed was limited to M2,8 (3.000km/h) mainly to extend the service life of the engines.

not anymore for MiG-31s

P.S. you need to think about new name: after 2021 wont be Merkelland anymore

do you suggest thet there is 1:1 mapping in all categories of equipment? They dont have Iskander SRBM or S-400 either.

There is a 1:1 mapping of requirements... what each country chooses to spend money on is a different matter.

They had SRBM and they will have some again when the INF treaty is torn up and ATCMS is replaced with a weapon with greater range.

Patriot is in the same category as S-400... as is THAAD, and probably a few European SAMs I never bother to follow.

In fact they often have two, because there is little unification between the USN and the other US Armed forces.... so for S-400 there is Patriot/THAAD on land and SM-3 at sea.

And you wonder why they scrapped this? not because of technology.  F-14 was to intercept Tu-160 or Tu-22 wanst it? Perhaps because  "Iceman" Kazansky wont fit the cockpit anyore?

It was supposed to defend the fleet from incoming Tu-22M3 strike aircraft with Kh-22M missiles, which were a serious threat... of course the threat has greatly increased... they need something even more than F-14... and they are not getting it.

That's the sweet life of a vassal and serf. France doesnt have any other fighter so what they were supposed to use? Super Entendard? New Dassault (German financed ;-) can be much better.

Actually the Russians don't have anything like the MiG-31 or MiG-41 on their carriers either... and they really don't need a land based equivalent because threats to France need to come across the Med or Europe to get to them... and there are no real threats there.

Yes, now I remember that news too. It is strange then that MiG-25 had no problems with the canopy but the 31 was limited to 2.83 M only because of that and not because of the engines?

When you say no problems with the canopy... the canopy was heated to 70 degrees C... you have to wear a full pressure suit for the air conditioning that it provides...

The air speed limits for the MiG-31 were 20 minutes at Mach 2.4, and 5 minutes at the top speed of Mach 2.83, from memory... but I was under the impression that they were all engine related...

By complex I mean two different types of engine in one plane. All that space, weight and complexity is going to be detracted from your range, payload and reliability. I would think a military plane in Russia (no country for hangar-queens) needs to be based on more mature technology.

We have seen their clever combination of rocket ramjet design where the large hollow area in the ramjet engine where fuel is normally burned is filled with a solid rocket motor that accelerates the missile to its initial speed for the ramjet to start now that the solid rocket fuel has burned away and left room for the ramjet to operate.

What we are talking about with the MiG-41 is very similar... a turbofan has a turbojet that also turns a fan on the front that blows cold dense air around the outside of the turbojet down the middle. A high bypass turbofan blows a large volume of air around the turbojet.

It would not take much to use that bypass airflow separate from the turbojet as a ramjet air flow, where fuel is burned but there are no turbine blades or other moving parts.

So the turbojet engine gets the aircraft moving and into the air and accelerates and climbs... the amount of air going through the turbojet is reduced and the amount going through the bypass duct is increased so the plane is flying in turbofan mode.

As speed gets even higher the bypass air starts operating as a ramjet and then turbojet/turbofan just idles...

Good info thanks. But the immediate question that arises is: why have they been knowing about this engine for 70 years and still no one has managed to take it out of the laboratory and into the serial production? Maybe it is not such an obvious thing? And why is it going to be ready right here right now for the MiG-41? I mean, I would be the first to celebrate if they pull that out, but from laboratory sample to deployment in the Artic with the folks of the VVS there are quite a few maturity steps you know?

The MiG-25 uses 11 ton thrust engines... the MiG-31 uses 15 ton thrust engines... there was a suggestion to fit the MiG-25 with the engines of the MiG-31 to see how that improved performance, but they never bothered... because the MiG-31 was the new plane and that is what they were going to use, so they didn't bother attempting a major upgrade of the MiG-25.

Keep in mind about the bypass ramjet suggestion... I didn't invent that... that is how the engines on the SR-71 worked.... at top speed of mach 3.3 or so there was no air going through the turbojet engines... it all bypassed the turbojet engines and acted like a ramjet.

Many people dismiss ramjets as being like turbojet engines on full AB all the time and therefore very high fuel consumption rates, but that is not the case... you could certainly pump as much fuel in as you wanted, but if you are operating at speeds of mach 2.5 or so fuel burn could be comparable to that of a turbojet in dry thrust.... except of course very few turbojets can operate at that speed at all let alone in dry thrust...

Could be even sooner.

Surely her policy on open borders to immigrants that has effected all of the EU will effect the EU for years if not decades to come, so in that sense it is probably best to call all of the EU Merkelland... Perhaps Mordor for short...

GarryB wrote:When you say no problems with the canopy... the canopy was heated to 70 degrees C... you have to wear a full pressure suit for the air conditioning that it provides...

I was rather meaning the canopy slowly melting out of place

The air speed limits for the MiG-31 were 20 minutes at Mach 2.4, and 5 minutes at the top speed of Mach 2.83, from memory... but I was under the impression that they were all engine related...

Didn't know those values thanks. Also heard thy were engine related, a normal turbojet flying 2.8 M has such a high air temperature after the compressor that it will be damaged. As said, maybe new materials allow the same configuration to be used at higher speeds but I doubt it would be much faster than MiG-31

We have seen their clever combination of rocket ramjet design where the large hollow area in the ramjet engine where fuel is normally burned is filled with a solid rocket motor that accelerates the missile to its initial speed for the ramjet to start now that the solid rocket fuel has burned away and left room for the ramjet to operate.

Cool, what missile is that?

What we are talking about with the MiG-41 is very similar... a turbofan has a turbojet that also turns a fan on the front that blows cold dense air around the outside of the turbojet down the middle. A high bypass turbofan blows a large volume of air around the turbojet.

It would not take much to use that bypass airflow separate from the turbojet as a ramjet air flow, where fuel is burned but there are no turbine blades or other moving parts.

So the turbojet engine gets the aircraft moving and into the air and accelerates and climbs... the amount of air going through the turbojet is reduced and the amount going through the bypass duct is increased so the plane is flying in turbofan mode.

As speed gets even higher the bypass air starts operating as a ramjet and then turbojet/turbofan just idles...

Yeah, essentially replicating the J58 seems the obvious solution, but it seems it was very complicated and was abandoned in the end. If the MiG-41 was a special purpose plane I would agree, but it being the substitute of the MiG-31 needs to be a sturdy plane. There is always the possibility of them managing to make such an engine simple and reliable enough but without any info on new applicable propulsion coming from Russia it is difficult to say. They may have a nuclear turbojet or whatever ready for the MiG-41 and we may not know a thing

LMFS wrote:

GarryB wrote:When you say no problems with the canopy... the canopy was heated to 70 degrees C... you have to wear a full pressure suit for the air conditioning that it provides...

I was rather meaning the canopy slowly melting out of place  

SR-71 (max speed Ma 3,3) wfter wiki

As speed gets even higher the bypass air starts operating as a ramjet and then turbojet/turbofan just idles...

Yeah, essentially replicating the J58 seems the obvious solution, but it seems it was very complicated and was abandoned in the end. If the MiG-41 was a special purpose plane I would agree, but it being the substitute of the MiG-31 needs to be a sturdy plane. There is always the possibility of them managing to make such an engine simple and reliable enough but without any info on new applicable propulsion coming from Russia it is difficult to say. They may have a nuclear turbojet or whatever ready for the MiG-41 and we may not know a thing  
[/quote]

Substitute of MiG-31 is wrong word. MiG-41 is successor, new gen  ith new tech. BTW SR-72 is under way and problem seem to be with hypersonic seed (6Ma), not heard abut engine layout be be blamed. You seem to have problems that you need an advanced plane to be simple. Same with VSTOL.


Could you please show me simple fighter for 4th gen?

Hole wrote:Could be even sooner.

AfD Land is what you'd prefer?

GarryB wrote:They had SRBM and they will have some again when the INF treaty is torn up and ATCMS is replaced with a weapon with greater range.
Patriot is in the same category as S-400... as is THAAD, and probably a few European SAMs I never bother to follow.
In fact they often have two, because there is little unification between the USN and the other US Armed forces.... so for S-400 there is Patriot/THAAD on land and SM-3 at sea.

Thank you for confirming that there are no direct counterparts form both sides
Patriot, Thaad + SM actually have similar role as S-400. Russia doesnet have CVNs) . No, not always there are direct counterparts.

GarryB wrote:

And you wonder why they scrapped this? not because of technology.  F-14 was to intercept Tu-160 or Tu-22 wanst it? Perhaps because  "Iceman" Kazansky wont fit the cockpit anymore?

It was supposed to defend the fleet from incoming Tu-22M3 strike aircraft with Kh-22M missiles, which were a serious threat... of course the threat has greatly increased... they need something even more than F-14... and they are not getting it.

I'd rather say they saw Russia falling apart so no more Tu-22 thread. But the had the wrong perspective

GarryB wrote:

Yes, now I remember that news too. It is strange then that MiG-25 had no problems with the canopy but the 31 was limited to 2.83 M only because of that and not because of the engines?

When you say no problems with the canopy... the canopy was heated to 70 degrees C... you have to wear a full pressure suit for the air conditioning that it provides...

300C was when S&-71 landed, in Flight was close to 400C. With 3,3Ma.

GunshipDemocracy wrote:Substitute of MiG-31 is wrong word. MiG-41 is successor, new gen  ith new tech. BTW SR-72 is under way and problem seem to be with hypersonic seed (6Ma), not heard abut engine layout be be blamed. You seem to have problems that you need an advanced plane to be simple. Same with VSTOL.

Could you please show me simple fighter for 4th gen?

Not really seeing the point in discussing about vocabulary, simple or complex are relative notions so we can keep talking until the end of time. But simplicity is a virtue for any piece of equipment and that is specially true for Russian military, this is undisputable as the notion that putting more than one type of engine makes a plane more complex than if it only had one of them. But in the end as you may imagine I know sh*t about the levels of reliability of the eventual SR-72 compared to what VVS would demand

LMFS wrote:.But simplicity is a virtue for any piece of equipment and that is specially true for Russian military, this is undisputable as the notion that putting more than one type of engine makes a plane more complex than if it only had one of them. But in the end as you may imagine I know sh*t about the levels of reliability of the eventual SR-72 compared to what VVS would demand

We dont know what precise solutions will be used for MiG-41. Using turbojet will be used for 4,3Ma ? I'm sure aerospace engineers know nothing about propulsion effectiveness.
Not sure why dpo you take primitive design for simplicity. MiG-31, Su-57, Zircon nor Burevestnik have nothing to do with simplicity.

BTW If VVS had so high demands then MiG-29k would never be built.

I was rather meaning the canopy slowly melting out of place

My understanding is that it is not the canopy itself that is the problem, it is the material holding it in place...

I remember reading a story about a guy flying in a MiG-25 two seater to high speed and high altitude, and it mentioned the heavy putty material used around the canopy... he asked about it and they said normal material did not work long at top speeds so they use that...

Didn't know those values thanks. Also heard thy were engine related, a normal turbojet flying 2.8 M has such a high air temperature after the compressor that it will be damaged. As said, maybe new materials allow the same configuration to be used at higher speeds but I doubt it would be much faster than MiG-31

It is a question of rotational speed putting enormous forces on the internal components of the engines... normally not good, but when the materials are heated as they are when operating at such speeds the problem is made worse... at that speed the SR-71 is getting very little thrust from its turbojet engines and it is basically flying on the ramjets.

Improved materials and cooling technology would certainly help, but the real solution is to transfer to a propulsion system more suited to flying at those speeds.

Cool, what missile is that?

Really?

The ones with air intakes...

SA-6. Kh-31, Onyx, Yakhont, Brahmos, Zircon (but with scramjet instead of ramjet).

Yeah, essentially replicating the J58 seems the obvious solution, but it seems it was very complicated and was abandoned in the end. If the MiG-41 was a special purpose plane I would agree, but it being the substitute of the MiG-31 needs to be a sturdy plane. There is always the possibility of them managing to make such an engine simple and reliable enough but without any info on new applicable propulsion coming from Russia it is difficult to say. They may have a nuclear turbojet or whatever ready for the MiG-41 and we may not know a thing

I trust them to be very clever and get something with very good performance but without being over engineered or complicated...

Substitute of MiG-31 is wrong word. MiG-41 is successor, new gen ith new tech. BTW SR-72 is under way and problem seem to be with hypersonic seed (6Ma), not heard abut engine layout be be blamed. You seem to have problems that you need an advanced plane to be simple. Same with VSTOL.


Could you please show me simple fighter for 4th gen?

When he says simple, I think he means not like a super expensive one trick pony that is very soon to become obsolete... ie spending a fortune making a mach 4 interceptor at a time when the enemy is working on a hypersonic bomber... ie mach 6.

The thing is that ramjet technology is pretty mature and mach 4 is well within ramjet performance capability.

A scramjet propulsion design should make hypersonic performance achievable, but would have a serious effect on the aircraft design.... including shape and materials.

What they could do is go for an aircraft design shape that allows for much higher speeds, but go for the less demanding speed performance goals so it will get into service in substantial numbers fairly quickly.

Later on a few design modifications and new materials and of course new scramjet engines could allow a transformation of the aircraft from a Mach 4 interceptor to something much faster later on... a bit like the Tu-144 being transformed into a rather more viable aircraft with the new NK-32 engines of the Tu-160 strategic bomber.

Thank you for confirming that there are no direct counterparts form both sides thumbsup thumbsup thumbsup
Patriot, Thaad + SM actually have similar role as S-400. Russia doesnet have CVNs) . No, not always there are direct counterparts.

That is dishonest.

There are counterparts... the fact that the American models are shit does not make them not contemporaries. Russia has one CV... what it lacks in propulsion it makes up for with ship killer missiles on board.

I'd rather say they saw Russia falling apart so no more Tu-22 thread. But the had the wrong perspective

In the 1990s I think they expected Russia would be buying F-16s in the 2000s when NATO was adopting F-35s...

They wanted the F-35 programme to go ahead and the F-14 was "old". They didn't even make it AMRAAM compatible so it was pretty much the only US military aircraft still using Sparrows...

The irony is that they probably made the right choice because the F-14 and Phoenix combination would be useless now against Kinzhal and in the near future against Zircon anyway... they would need a much better missile... they would have been vulnerable anyway...

300C was when S&-71 landed, in Flight was close to 400C. With 3,3Ma.

The SR-71 is not the same plane as the MiG-25.

But simplicity is a virtue for any piece of equipment and that is specially true for Russian military, this is undisputable as the notion that putting more than one type of engine makes a plane more complex than if it only had one of them.

Many Russian aircraft have APUs so they don't need ground power to operate them at far flung airstrips with little or no support equipment...

Most aircraft engines are fine for normal speed ranges... from zero up to mach 2.4 or so, but above mach 2.4 you need a different engine type.

Imagine if jet engines were inefficient at below 800km/h... to make a mach 2 fighter you would need a propeller engine to takeoff and land and fly up to a speed where you could start your jet engine... the only difference is that it is two different types of jet engine... a turbojet and a ramjet.

Using turbojet will be used for 4,3Ma ? I'm sure aerospace engineers know nothing about propulsion effectiveness.

Trying to make a pure turbojet operate up to mach 4.3 would be like making a turboprop engine that can operate up to mach 1.8... it is not worth the effort to try.

BTW If VVS had so high demands then MiG-29k would never be built

It wasn't. They are using MiG-29KRs.

GarryB wrote:

Cool, what missile is that?

Really? The ones with air intakes...SA-6. Kh-31, Onyx, Yakhont, Brahmos, Zircon (but with scramjet instead of ramjet).

https://dictionary.cambridge.org/dictionary/english/irony
he meant my suggestion for potential  propulsion for MiG-41

GarryB says wrote:When he says simple, I think he means not like a super expensive one trick pony that is very soon to become obsolete... ie spending a fortune making a mach 4 interceptor at a time when the enemy is working on a hypersonic bomber... ie mach 6.

LMFS man is defending MiG-31 so idotn think he is taking about real progress.   MiG-41 is supposed to new one.  Why to buil dbasing on old tech?

GarryB wrote:What they could do is go for an aircraft design shape that allows for much higher speeds, but go for the less demanding speed performance goals so it will get into service in substantial numbers fairly quickly.

Later on a few design modifications and new materials and of course new scramjet engines could allow a transformation of the aircraft from a Mach 4 interceptor to something much faster later on...

Definitely a way to approach this. But if you see propulsion efficiency till 5Ma PDE if much better then any ram- or scramjet till ~5Ma (mind MiG-41 is to be 4,3 Ma)

GarryB wrote: That is dishonest. There are counterparts... {} Russia has one CV... what it lacks in propulsion it makes up for with ship killer missiles on board.

 
Kuz has neither catapult, 100kt displacement nor  nuclear propulsion and you want to put her into one category with Ford class?  
and this is honest?    

GarryB wrote: The irony is that they probably made the right choice because the F-14 and Phoenix combination would be useless now against Kinzhal and in the near future against Zircon anyway... they would need a much better missile... they would have been vulnerable anyway...

Although logically true, but unlikely this was their reason to retire.

GarryB wrote:

300C was when S&-71 landed, in Flight was close to 400C. With 3,3Ma.

The SR-71 is not the same plane as the MiG-25.

do you suggest that with the same speed MiG-25 had no temp increase ?

GarryB wrote:

BTW If VVS had so high demands then MiG-29k would never be built

It wasn't. They are using MiG-29KRs.  

4 on Kuz (of which 3 working )

GarryB wrote:It is a question of rotational speed putting enormous forces on the internal components of the engines... normally not good, but when the materials are heated as they are when operating at such speeds the problem is made worse...

Improved materials and cooling technology would certainly help, but the real solution is to transfer to a propulsion system more suited to flying at those speeds.

Every material has a fluency and it increases with temperature. All that suits very badly with ultra-tight aircraft engine tolerances...

Maybe propulsion with hydrogen and some kind of "intercooler" using the liquid fuel as in SABRE could do but I would expect something less sophisticated/expensive for a tactical interceptor.

When he says simple, I think he means not like a super expensive one trick pony that is very soon to become obsolete... ie spending a fortune making a mach 4 interceptor at a time when the enemy is working on a hypersonic bomber... ie mach 6.

The thing is that ramjet technology is pretty mature and mach 4 is well within ramjet performance capability.

A scramjet propulsion design should make hypersonic performance achievable, but would have a serious effect on the aircraft design.... including shape and materials.

What they could do is go for an aircraft design shape that allows for much higher speeds, but go for the less demanding speed performance goals so it will get into service in substantial numbers fairly quickly.

Later on a few design modifications and new materials and of course new scramjet engines could allow a transformation of the aircraft from a Mach 4 interceptor to something much faster later on... a bit like the Tu-144 being transformed into a rather more viable aircraft with the new NK-32 engines of the Tu-160 strategic bomber.

I mean having one kind of engine and not two. Airframes are built around the engine, so if you duplicate that burden you end up with strongly reduced capabilities, apart from the additional costs and complications. And Russia as said has no use for hangar queens. The fleet of MiG-31 is big enough for needing a relatively cheap and sturdy plane to replace it, not some half backed DARPA prototype. And especially for a stated speed of 4 M instead hypersonic all that complication would be too much IMO. If you need to go hypersonic and there is no other way to achieve that ok, otherwise it makes no sense.

Your approach may be one possibility, but in reality designing something without knowing what kind of detailed requirements the new propulsion is going to demand is extremely risky.

Imagine if jet engines were inefficient at below 800km/h... to make a mach 2 fighter you would need a propeller engine to takeoff and land and fly up to a speed where you could start your jet engine... the only difference is that it is two different types of jet engine... a turbojet and a ramjet.

That is why you have turbofans and soon variable cycle. The development of such complicated units takes ages, since when are variable cycle being discussed and prototypes built? The case with making something similar but with a ramjet would be like that, with the complication that you have a much narrower application field and hence much less experience to draw lessons from.

Gunship wrote:LMFS man is defending MiG-31 so idotn think he is taking about real progress.   MiG-41 is supposed to new one.  Why to buil dbasing on old tech?

I am not so fool to have an agenda on this matter. I win nothing irrespective of what kind of plane MiG-41 will be. And the requirements, schedule etc. are very far from being a closed case so I cannot even make a good estimation of what would be the logical design philosophy. Hence I submit the references I find, among them, the words of a Russian official indicating clearly that the MiG-31 is still unsurpassed (which I strongly agree) and that basing a future model on it would be a logical possibility. Who am I to disagree, considering we don't know what capacities MoD will demand from the -41? There are not even other programs abroad with the same goals and the Russian solution will pretty much unique so we know pretty much nothing.

LMFS wrote:

Gunship wrote:LMFS man is defending MiG-31 so idotn think he is taking about real progress.   MiG-41 is supposed to new one.  Why to buil dbasing on old tech?

I am not so fool to have an agenda on this matter. I win nothing irrespective of what kind of plane MiG-41 will be. And the requirements, schedule etc. are very far from being a closed case so I cannot even make a good estimation of what would be the logical design philosophy. Hence I submit the references I find, among them, the words of a Russian official indicating clearly that the MiG-31 is still unsurpassed (which I strongly agree) and that basing a future model on it would be a logical possibility. Who am I to disagree, considering we don't know what capacities MoD will demand from the -41? There are not even other programs abroad with the same goals and the Russian solution will pretty much unique so we know pretty much nothing.

My suggestion is based on your posts where you were surprised why do they need something faster if MiG-31 is so good. It was not about agree or disagree this is abut philosophy how to approach the problem.



As for MiG-31 and 41 relation. I never heard any official statement about development on base of MiG-41. Only one opinion of former military AFAIR. If they really need anything really better they need to build form scratch.


Below oldie bu goldie. I dont think that this was just for journos...rather very early stage of development.

2016/06
https://iz.ru/news/622079