5th gen light mulltirole fighter/Mikoyan LMFS

miketheterrible wrote:I don't ever see this coming out to be honest.  If the government isn't funding it, I doubt much beyond a flying model at best like Su-47.

Rostec is a state company so the government cannot be against it. This is the typical case where the state gives the initiative to the companies to bet on the technologies they believe in and allow them to bring them to the point where they are real and can be demonstrated instead of begging the MIC to inspire them with their pipe dreams, as it happens in the US. Happens all the time with weapons systems that end up in the armed forces.

On other hand, we know Putin has had requested a Jump Jet to be created in the newest SAP program.  But no word on that.

There is a possibility of merging projects and that this ends up as a jump jet.

Normally I would say this cannot end up well. But specifically in this case there is one chance I have talked before about but I have not had time yet to make even a crappy drawing of...

An unmanned variant where the cockpit goes away and is replaced with a lift fan would remove most of the layout problems the F-35 has and would allow a CTOL version with almost no downsides and a high level of commonality.

The-thing-next-door wrote:
Why would they make thier own f35 when it has been clearly shown that such aircraft are suboptimal at best.

There is a niche for such planes I think:

- For many potential customers, which will never have a real carrier and need to do the best they can with a LHD or similar compromise solutions
- For the VMF, since vessels like the 23900 would be better of with a few high capability UCAVs like these aircraft would be.
- In the kind of not so high intensity conflicts these planes would be used, there would normally still be some way to keep at least eventual contact with the planes, which would therefore not need to be fully autonomous. Semi autonomous machines are already a reality in which no constant link to remotely pilot them is needed but just eventual comms to exchange commands and tactical / targeting information. So development would not need to be delayed until some breakthrough AI technology appears.

So if the base platform can be kept common with the CTOL version without serious downsides, then I see no reason to close this possibility.

mnztr wrote:
The F-35 as a VTOL jet is FANTASTIC, as a pure fighter, mediocre. LM paid YAK about 350M for the YAK 141 technology that underpins the F-35. The US went with shaft driven lift fan which requires a large radius. I am not sure what other ideas are possible The smart thing for the US to do would be to make the fuse/wing of the F-35 non-VTOL much differnt then then VTOL. That said I have no idea what engineering/political constraints they were under.

I agree the F-35B is a great STOVL fighter, in fact this is the only version that I think is a real achievement. The lifting fan is a genius idea for a STOVL plane, its radius is not exaggerated (in fact the problem is more the excessive weight and its unfavourable distribution than the propulsion concept itself) and the main downsides come from placing it centrally in the plane instead of it being closer to the nose where it would not need to be so powerful, it would not ruin the best place for the weapons bays and it would allow to move the main engine back for proper aero, internal fuel etc. They really screwed the plane with that layout. But if the lifting fan goes to the front, where a cockpit would be, then none of those problems appear and you would have a STOVL with high commonality with the CTOL and none of the versions would be saddled with bad aero, low internal capacity and overweight.

Well, I managed to do a hack with the F-35B to illustrate the idea

The original:



The improved version:



Nevermind the extremely crappy quality of the work or the finishing, the idea is that, by moving forward the lifting fan, the main engine can go backwards (otherwise the lifting fan would need to lift too much weight and it would not be technically practical). Observe the HUGE amount of space liberated at the plane's CoG (where it should be) for weapons and fuel, as well as the big potential improvement in the plane's fineness ratio that it would allow, both because the nozzle aero would improve and also because there would be no need for the biggest sin of the F-35, that is, placing the bays parallel to the engine, which is BTW a very big one.

Problem with that is the shaft becomes very long and it goes right through the cockpit. I would have done the fan as a stage of the turbine, maybe clutched and moved the air to pressureised zones in the wings. Not sure if it would work buy I do assume they did beat all the ideas to death and modelled every option. One thing I would consider is a seperate UAV platform that is self powered and assists the plane to a vertical takeoff, then the plane gains speed, disconnects and the UAV platform return to the deck. Landing is by cable arrestor.
Yet one more option is 2 smaller fans located in the landing gear wells. Gear down doors open, plane picks up speed, fan drive off, gear up doors closed.

mnztr wrote:Problem with that is the shaft becomes very long

Yes, this is an obvious issue that would need to be clarified, the shaft handles MW in power and therefore making it very long is not good. But I think it is doable.

and it goes right through the cockpit.

It is an UCAV, there is no cockpit. That is the trick.

I would have done the fan as a stage of the turbine, maybe clutched and moved the air to pressureised zones in the wings. Not sure if it would work buy I do assume they did beat all the ideas to death and modelled every option.

They do this for the roll posts on the wings, but the amount of lift generated is a fraction of the main lifting elements. I assume if this was really doable there would not be need for the kind of solutions we see, but who knows.

One thing I would consider is a seperate UAV platform that is self powered and assists the plane to a vertical takeoff, then the plane gains speed, disconnects and the UAV platform return to the deck. Landing is by cable arrestor.

We discussed this a couple of years ago

Yet one more option is 2 smaller fans located in the landing gear wells. Gear down doors open, plane picks up speed, fan drive off, gear up doors closed.

That would save some of the space for the nozzles but would introduce aero, structural and systems interference... I am not sure but maybe the landing gear wells could indeed be used with a smart design of the undercarriage. It would be compatible with the idea in the drawings above, as a further optimization.

We have already discussed this many times so you now single engine + manned / unmanned versions is what I have proposed to make the initiative versatile and cheap enough, if they would use the unmanned version as a base of a STOVL plane it would be even better, but I am not holding my breath for it.

I know we have discussed it, this is something they might want to do on their own money, but that is no guarantee of any success on any terms... a plane too small to be effective is a bad idea whether it is cheaper than an effective plane or not.

Trying to make it STOVL is just mental and a ridiculous choice... the likely potential for aircraft that can take off or land vertical is a tiny niche which will render it excessively complex and fragile and for what... it would make no difference to any user except some idiot trying to justify tiny carriers which are expensive death traps with no endurance... it would be a crime to spend extra money on VT only to end up rendering their carriers useless wastes of time and money... they would be better off using Ka-52s as fighters.

The Su-57 and S-70 show a fighter and a specialised drone that operates with it make sense in the twin engined fighter and single engined drone pairing can work and does have potential... so why break that formula for a cheaper lighter option...

But sooner or later the lighter fighter will be produced, this is almost for sure.

Without interest from the Russian AF who cares?

The only cheap 5th gen fighter will be a drone...

I don't see how a single engine fighter is cheaper then a 2 engine, I think F-35 blew apart that notion. What engine would they use? NK-32? Maybe that is the plan, restart production and build a fighter around that beast!!! Is it suitable for a fighter in terms of power/weight ratio?

What gets me is that two engines spaced apart gives internal volume for internal weapons and decent fuel load... when there is only one engine then the only way to create internal volume for weapons and enough fuel is to go fat like the new F-16s with conformal fuel tanks... which negates all the benefits of the slim low drag potential of a single engine design...

That would defeat the purpose of the single engine plane using the same engine of the heavy fighters for economic and logistical reasons though.

But the engine from the bigger fighters are expensive... look at the US experience... the F-16 is not cheap... the F-5 is cheap because it uses small cheap simple engines which makes it affordable to buy and to operate... the upgrade for it was the single engined F-20 which by your standards should be the ideal version of it as it essentially would be an F-5 with an RD-33 fitted to give it better performance... the the increased power single engine was too expensive to operate and maintain and the F-20 idea tanked.

Remember that the Mig-35 and SU-35 only have a 9500 kg MTOW difference. I think Russia with their developments on the MIG-35 have signalled that short range fighters are of little use to them.

The MiG-35 was about lower operating costs so we really wont know if that is a success until they get it into service and get some time under their belts.

If they actually wanted a cheap light fighter they would be buying MiG-29Ms right now... but they are clearly not... they want quality over quantity, which again suggests that a smaller lighter single engined fighter of lower performance wont be of interest to them either.

The NK-32 is only 3500 kg. SU-35 has 64K lb of thrust, so 55K will make for a nice supercruising beast with some mods. NK-32 is also recently refeshed.

Not that I think it would be a good idea, the Yakovlev design bureau did suggest a larger heavier Yak-141 alternative that they called Yak-43 that looked a hell of a lot like the F-35 but with a version of the NK-32 engine as the main power plant and the lift engines... not the lift fan design used in the F-35... it was the thrust vector nozzles that could take a full power main jet engines thrust rotated 90 degrees or more that they sold to the US...

MiG-35 is hardly a proof of what Russia wants to do in the future right, because it was already determined by the 40+ old development of the MiG-29. The plane itself was extremely limited range-wise, and the modernization has tried to create a proper multirole plane with usable range that can be presented on the international market without it being an instant disqualification reason.

They have Su-35s and Su-30s and Su-57s... what the fuck do they need a medium fighter with long range for?

Increasing its fuel fraction to meet your needs for extra long range will make it fat and slower and much less agile... why are you complaining that a medium fighter is not heavy enough and then suggest a light fighter will be better... somehow the modern aerodynamics of this new magical VSTOVL super machine can be tiny and slim and have enormous payload and better flight range than the bigger heavier planes they are already using.

Is it the canards generating that extra lift that makes the plane into an anti gravity super plane?

On the other hand what you say regarding the MiG being like 2/3 of the Sukhoi is right and has been commented, as a middle fighter it occupies the space between the light fighter roughly 1/2 the size of a Sukhoi and the heavy fighters

But we have seen the aircraft that fills the role of half the size and engine power of the Sukhoi... it is called the S-70.

That is precisely the reason why I find it suboptimal if you already have heavy fighters and exactly the reasons some others find them better than light fighters, so it depends on your opinion and how you see things developing and different platforms balancing each other.

Light fighters are nice for countries that cant afford or don't need anything better, but as we saw in the Falklands Islands war, or most of the Middle East wars... when cheap simple little light fighters come up against big heavy fighters they often come off worse because missile technology and radar technology has improved since the Vietnam war when little agile planes could get in close and harrass those big heavy lumbering planes... the Su-27 and MiG-29s are manouverable capable fighters with helmet controlled high offboresighted AAMs...

Remember we have not seen any purpose-built A2A UCAV, so that part of the combat remains a field for manned fighters.

What do you think the S-70 is?

The new approach announced by Chemezov is a change for good IMHO and will allow to mix the reliability of manned operations with the increased numbers and capacity to take risks of unmanned platforms. This is the only way IMHO that the current air forces can transform into an unmanned fleet with acceptably low risk.

I would prefer to hear further information first... companies make all sorts of statements all the time... without funding it is just talk.

30 is still under development whole Su-57 has been finalized and sent into production

No point delaying aircraft over engines, you can swap them later

This new fighter design they are talking about wont be flying for at least 5 years... likely probably much more.

There is a possibility of merging projects and that this ends up as a jump jet.

Actually a twin jet that has a wider fuselage would actually be easier to make with a front mounted lift fan just behind the cockpit, but it would still be a dog with huge internal volume taken up with useless empty space.

The F-35 as a VTOL jet is FANTASTIC, as a pure fighter, mediocre.

No it isn't... apart from stealth and supersonic speed which because of its problems it will likely never actually achieve it is totally inferior to the AV-8 II which was an operational aircraft of much better performance and a fraction of the cost... there are no fantastic VTOL fighters.

LM paid YAK about 350M for the YAK 141 technology that underpins the F-35.

They paid for the rotating main engine nozzle that can take high thrust full AB while vectoring at angles past 90 degrees... the Yak design bureau always used lift jets and not fancy lift fans driven by the main engine because of the volume it takes up.

The lift fan has a few advantages... it blows cold air so hot gas ingestion into the main engine intakes is not a problem, and it is probably lighter and perhaps simpler than putting two extra jet engines like Yak did.... the two 4 ton thrust engines they used in there planes meant it had the equivalent of an Su-25s two jet engines lifting its nose except the engines on the Yak used AB.

Normally extra engines improves safety because the chance of one engine failing is x, but the chances of more than one engine failing at the same time is much lower, but in this case any of the three engines failing will cause a crash so the chances of a crash or accident is tripled not reduced.

The fundamental problem with the fan is that the volume and shape means you can't fit it into a single engined supersonic fighter without compromising internal volume for fuel and it is made worse with 5th gen fighters because weapons need to be internal too.

Rostec is a state company so the government cannot be against it.

The government was against the Su-25... they thought the VSTOL Yak-38 would be a better ground attack aircraft... they already had the latter in production and service with the navy and making more will make them cheaper and of course being able to operate from any 15 square metre area of flat ground means you could base them anywhere... they were going to be fantastic... but then they tested both in operational conditions in Afghanistan and the Yak-38 was terrible and the Su-25 was fantastic... and managed to be much cheaper while having more than one engine... pretty astounding... I know...

Happens all the time with weapons systems that end up in the armed forces.

But much more often in weapon systems that die and no one ever hears about except 50 years later in books about the design bureaus and their failed concepts and designs that never left the paper prototype level.

An unmanned variant where the cockpit goes away and is replaced with a lift fan would remove most of the layout problems the F-35 has and would allow a CTOL version with almost no downsides and a high level of commonality.

A cat launch could do the same without the internal space hog lift fan design and wing tip and nose and tail puffer jets for stability and manouver in the hover...

- For many potential customers, which will never have a real carrier and need to do the best they can with a LHD or similar compromise solutions

And how many of them will buy the thousands of aircraft needed in this day and age to justify the development costs of not just a 5th gen fighter but also a VSTOL fighter too...

- For the VMF, since vessels like the 23900 would be better of with a few high capability UCAVs like these aircraft would be.

There is no evidence they want anything other than fixed wing carriers with EMALs for air power and air protection of their ships.

Their helicopter carriers are for carrying helicopters... the Ka-52K makes no sense if they want an AV-8III as well.

- In the kind of not so high intensity conflicts these planes would be used,

Will they have a meter on board determining the intensity of the conflict so if it goes too high they automatically fly back to base and summon a real carrier with real fighters to do the job?

I agree the F-35B is a great STOVL fighter, in fact this is the only version that I think is a real achievement.

It hasn't done anything except cost a huge fortune for those who bought it.

The conventional models are afraid to enter Syrian airspace... what chance approaching something really dangerous like a a Russian mine layer with an AK-630 turret.... scary scary...

The lifting fan is a genius idea for a STOVL plane,

Oh please... really? If you were talking about the Pegasus engine then I might agree, but it is the lift fan that has turned the F-35 from a dog fighter to a dog.

It is the opposite of everything you talk about... it is fat and slow and has poor range and is fucking expensive to buy and even more expensive to operate...

its radius is not exaggerated

There is nothing about the aircraft that is not exaggerated.

Well, I managed to do a hack with the F-35B to illustrate the idea

Hahaha... of course... you can shift around the lift fan to anywhere you please and it wont change anything important at all...

Shifting the engine back and moving the fan forward creates more space, but without increases in power then there can be no increases in weight so the extra space freed up can't be used... and you don't have a pilot...

Maybe shifting the fan and the engine means more angle of motion so they can both be half the size and half as powerful and still have the same effect?

That would free up even more space...

Problem with <snip>tion is 2 smaller fans located in the landing gear wells. Gear down doors open, plane picks up speed, fan drive off, gear up doors closed.

Or make it wider and have two widely separated engines which will produce ample space for a very wide and very effective lift fan at the front and ample engine power for speed while also ample space for internal weapons and internal fuel to give it enough range and weapon load to actually be useful...

It is an UCAV, there is no cockpit. That is the trick

If it is a UCAV then why bother changing the balance and design at all... just fit an extra fuel tank where the cockpit is and keep maximum commonality with the original piece of junk.

GarryB wrote:
What gets me is that two engines spaced apart gives internal volume for internal weapons and decent fuel load... when there is only one engine then the only way to create internal volume for weapons and enough fuel is to go fat like the new F-16s with conformal fuel tanks... which negates all the benefits of the slim low drag potential of a single engine design...


They have Su-35s and Su-30s and Su-57s... what the fuck do they need a medium fighter with long range for?

Increasing its fuel fraction to meet your needs for extra long range will make it fat and slower and much less agile... why are you complaining that a medium fighter is not heavy enough and then suggest a light fighter will be better... somehow the modern aerodynamics of this new magical VSTOVL super machine can be tiny and slim and have enormous payload and better flight range than the bigger heavier planes they are already using.

There are all kinds of options to put more fuel in a single engine plane if its designed at the outset for this. Saying it needs to be fat is just not correct. Fuel is dense and does not require that much space volume wise. You can stretch the fuse a bit and carry a lot of extra fuel. Conformal tanks are an afterthought. Having fuel capacity does not add much weight unless you are full of fuel, does not mean you have to fill the tanks full everytime you fly. you just put in what you need like you always do. It adds capablity with not a lot of cost. You can trade of weapons load for radius, which is a desirable option for any airforce. You can also fuel up in the air and fly over MTOW loaded with weapons and fuel. Fuel capacity is flexibility and in itself does not add a lot of weight and cost. F-16 only has 3200kg of internal fuel capacity and 7700kg of weapons payload capacity. So you can see a its quite easy to add fuel capacity. The Japanese did just this with the F-2 and made a slightly larger F-16 with 25% more fuel. Why would Russia want a long range medium fighter? Well because Russia is HUGE. Also Russia cannot rely on a global fleet of 700 fuel tankers like the USA. Even Sweden has found room for a lot more fuel (40%!!)for the Gripen E and even the MIG 29 now has a lot more internal fuel. from 3500 KG to 4800KG on the Mig 35.

GarryB wrote:Without interest from the Russian AF who cares?

There is and has been talk in the AF and government of such a plane for ages, as well as previous programs like the LFI. You have actually no proof they don't have interest, just your opinion.

The only cheap 5th gen fighter will be a drone...

This is exactly what they are doing. A light A2A focused fighter is going to be similar be it manned or not, so you create the two versions and get the best return of the investment. It is smart.

They have Su-35s and Su-30s and Su-57s... what the fuck do they need a medium fighter with long range for?

No long range but decent range.

Increasing its fuel fraction to meet your needs for extra long range will make it fat and slower and much less agile... why are you complaining that a medium fighter is not heavy enough and then suggest a light fighter will be better... somehow the modern aerodynamics of this new magical VSTOVL super machine can be tiny and slim and have enormous payload and better flight range than the bigger heavier planes they are already using.

Is it the canards generating that extra lift that makes the plane into an anti gravity super plane?

What is all this aggressive shit?

But we have seen the aircraft that fills the role of half the size and engine power of the Sukhoi... it is called the S-70.

If you do not differentiate a strike platform from a fighter you have a problem Garry. It should be pretty obvious what purpose the S-70 serves.

Light fighters are nice for countries that cant afford or don't need anything better,

Change light by medium and you are right. Big AFs use the heavy fighters to guarantee performance and complement them with light ones for numbers, it is countries with lesser air forces that have to rely on a compromise solution in form of medium fighters which are normally neither as capable as heavy ones nor as cheap as the light ones.

What do you think the S-70 is?

Not a purpose built A2A platform, by any stretch of the imagination.

I would prefer to hear further information first... companies make all sorts of statements all the time... without funding it is just talk.

Well, funding they have, coming from Rostec. This is no start-up you know, it is the biggest technology conglomerate in Russia and owned by the state. Maybe they know what they do?

No it isn't... apart from stealth and supersonic speed which because of its problems it will likely never actually achieve it is totally inferior to the AV-8 II which was an operational aircraft of much better performance and a fraction of the cost... there are no fantastic VTOL fighters.

Are you joking? The Harrier was a mess and the F-35B is simply on another category. Do yourself a favour and take a look at the specs please...

The lift fan has a few advantages... it blows cold air so hot gas ingestion into the main engine intakes is not a problem, and it is probably lighter and perhaps simpler than putting two extra jet engines like Yak did.... the two 4 ton thrust engines they used in there planes meant it had the equivalent of an Su-25s two jet engines lifting its nose except the engines on the Yak used AB.

Normally extra engines improves safety because the chance of one engine failing is x, but the chances of more than one engine failing at the same time is much lower, but in this case any of the three engines failing will cause a crash so the chances of a crash or accident is tripled not reduced.

You are right, and on top of that it allows the same engine to produce a huge lift augmentation by changing the effective bypass ratio, so it can lift the plane without AB... it is a brilliant idea in fact.

The fundamental problem with the fan is that the volume and shape means you can't fit it into a single engined supersonic fighter without compromising internal volume for fuel and it is made worse with 5th gen fighters because weapons need to be internal too.

The problem of the plane is not really the fan, it is the weapon bays. The fan has the broad width of the central fuselage as demanded by the engine and cockpit (lift fan inlet is just 17 cm bigger than the engine's diameter), while the plane is like twice that due to the engine being very at the front and the bays being parallel to it. Look below how they crammed the weapons in any angle they could fit them, it is obvious they had a serious space and aero problem there:

The government was against the Su-25...

I notice you question Rostec because it has no government money, but now you say the government was wrong when they wanted STOVL. Either way, who disagrees with you is wrong, be it government, Rostec or whoever. OK I get it.

But much more often in weapon systems that die and no one ever hears about except 50 years later in books about the design bureaus and their failed concepts and designs that never left the paper prototype level.

Maybe, we will see.

And how many of them will buy the thousands of aircraft needed in this day and age to justify the development costs of not just a 5th gen fighter but also a VSTOL fighter too...

This is a niche segment but it is relevant since for most countries this is by far the best "power projection" tool they will get, some like Turkey will have their LHD and soon will have no planes for them. Plus Russia plus China it justifies, I think, the development, considering it is just a version of a plane you are going to design either way. I have seen programs with a way worse business case for sure.

There is no evidence they want anything other than fixed wing carriers with EMALs for air power and air protection of their ships.

This allows to improve the UDKs and gives them a bit more of capability so your fleet can take care of more missions and your carriers are not tied to almost trivial roles like avoiding provocations on low intensity conflicts.

Their helicopter carriers are for carrying helicopters... the Ka-52K makes no sense if they want an AV-8III as well.

They have discussed about the jump jet and quite seriously I would say (they are supposed to be developing one), so they see some use in it. And of course VKS sees no problem in having both fixed and rotary wing aircraft, contrary to what you argue.

Will they have a meter on board determining the intensity of the conflict so if it goes too high they automatically fly back to base and summon a real carrier with real fighters to do the job?

I am sure the command will know when a carrier is needed. Some assets with good A2A capability on board an UDK just raise the bar against provocations and gives better capability overall. VMF is not going to have that many carriers to park them everywhere.

Hahaha... of course... you can shift around the lift fan to anywhere you please and it wont change anything important at all...

Shifting the engine back and moving the fan forward creates more space, but without increases in power then there can be no increases in weight so the extra space freed up can't be used... and you don't have a pilot...

You are faster to be dismiss than to understand it seems. Obviously this is nothing but a sketch to understand what I am talking about, so you should not expect to see a finished design. The bays at the sides would disappear and would be moved to the center line of the plane, in front of the engine, there you have your weight and cross sectional area reduction.

Yes, with a pilot you need a cockpit just in the place you would need your frontal propulsion to be. It is a downside, but at least in this way the limitation is confined to the STOVL, version which is the one with lesser combat potential, and not the other way around like in F-35, where the really relevant and abundant versions A and C were screwed to get the B version right.

Maybe shifting the fan and the engine means more angle of motion so they can both be half the size and half as powerful and still have the same effect?

I have not reduced the size of any of those, even when it could be actually done. The further you move the lift fan to the front, the longer its torque arm and therefore it will be able to balance the plane with less thrust, that means, you can produce a bigger portion of the total lifting thrust at the main engine and make the frontal propulsion assembly smaller. That is a main limitation of the F-35, look how far forward the main engine was brought in order to be able to balance the plane.

That would free up even more space...

If it is a UCAV then why bother changing the balance and design at all... just fit an extra fuel tank where the cockpit is and keep maximum commonality with the original piece of junk.

That sarcasm is just showing you don't understand a bit of what is proposed here, and that is sad.

I wonder what the specs are for using an electric hybrid set of lift fans for a VTOL plane. Its pretty obvious that future jet fighters will need a lot more electrical capacity for lasers, EM cannons etc. What would the weight be for a 25,000 KWH generator and 2x 12000 HP electric lift fans? You will eliminate the gearbox and shaft. Could a flying wing fighter work using lift fans to augment manuverability? So many cool options.

mnztr wrote:I wonder what the specs are for using an electric hybrid set of lift fans for a VTOL plane. Its pretty obvious that future jet fighters will need a lot more electrical capacity for lasers, EM cannons etc. What would the weight be for a 25,000 KWH generator and 2x 12000 HP electric lift fans? You will eliminate the gearbox and shaft. Could a flying wing fighter work using lift fans to augment manuverability? So many cool options.

This is a relevant question, still the current solution is very hard to beat in weight and simplicity, even when the shaft + gear assembly is far from being a trivial piece of technology. The shaft in the F135-PW-600 transmits up to 29,000 shp (!). To match that with a generator and a motor you would need literally tons of extra weight and a huge volume that could not fit the aircraft.

There are some numbers and background here, so you can see power density of generator, superconducting motors, cabling and cooling (cryogenic) equipment:

https://iopscience.iop.org/article/10.1088/1361-6668/aa833e/pdf

LMFS wrote:

This is a relevant question, still the current solution is very hard to beat in weight and simplicity, even when the shaft + gear assembly is far from being a trivial piece of technology. The shaft in the F135-PW-600 transmits up to 29,000 shp (!). To match that with a generator and a motor you would need literally tons of extra weight and a huge volume that could not fit the aircraft.

There are some numbers and background here, so you can see power density of generator, superconducting motors, cabling and cooling (cryogenic) equipment:

https://iopscience.iop.org/article/10.1088/1361-6668/aa833e/pdf

I am sure it will continue to be a moving target. Another way is to drive the lift fans from reaction jets in the blade tips and use pressure from the turbine. This is pretty noisy but I cannot imagine it being much noiser then the current engine screaming away on lift off.

^ There was some noise a couple years back that Russia was working on a vertical takeoff jet. What is the latest on that ?

Who supports this idea ? I don't think it's worth the effort. But it would be cool.

Backman wrote:^ There was some noise a couple years back that Russia was working on a vertical takeoff jet. What is the latest on that ?

Who supports this idea ? I don't think it's worth the effort. But it would be cool.

I think the last to say something was Borisov, so it is not an empty rumour. I am not sure it was ever 100% clear they were talking about a STVOL plane and not about a STOL one though...

There are all kinds of options to put more fuel in a single engine plane if its designed at the outset for this. Saying it needs to be fat is just not correct. Fuel is dense and does not require that much space volume wise. You can stretch the fuse a bit and carry a lot of extra fuel.

I am responding to the claim that single engined aircraft by definition are slimmer and more aerodynamic and don't need as much fuel or maintenance compared with a similar twin engined design.

F-16 only has 3200kg of internal fuel capacity and 7700kg of weapons payload capacity.

What loadout can an F-16 fly with having weapons only at 7.7 tons?

Like many aircraft someone has worked out the max weight ratings for all its weapon points and added them up, but achieving such a payload is simply not practically possible.

Why would Russia want a long range medium fighter? Well because Russia is HUGE.

This is the stupidity I am fighting against... you want a fighter to protect an area... extra range is nice but it comes at a cost in terms of weight and also drag... internal fuel is the best compromise because it does not increase drag but it sure does ruin that nice power to weight ratio you had as a fighter.

Having Flankers operating from one airbase does not mean it can cover the airspace 2,000km in any direction, while a Fulcrum operating from the same airfield only covers 1,000km radius... very simply in western Russia there are going to be other air fields and other units all over the place and the 2,000km radius circle around that Flanker airfield is going to serious overlap all the airfields nearby.

If there is a target detected 1,500km from your airfield you are not going to send an Su-35 to check it out... you are going to look at the closest airfield to the target which might be a Fulcrum airfield that is 300km away from the target and you are going to send them.

The Flanker might have the range to get there but it wont have the time... if you are going to buy Flankers and base all your military airfields 2,000km apart then any idiot can map a flight path that goes between them so launching flankers all the time but to reach the target before it goes past they will have to go supersonic which means their 2,000km range flight radius just became a 1,000km flight radius if you are lucky.

Thinking a Flanker can actually protect twice the volume of airspace is just bullshit... in fact having shorter ranged fighters is better because they wont get called away to do jobs thousands of kms away from what they are supposed to be protecting.

Also Russia cannot rely on a global fleet of 700 fuel tankers like the USA.

Russia doesn't need that bullshit... except a very rare one off ferry transfer with external tanks and inflight refuelling stops which could be airborne but could just as easily be air field landings too.

They have fighters to protect their bases and the surrounds and they have longer range fighters for longer ranged missions... they don't all need long range that is just dumb to expect lighter cheaper simpler fighters to be able to fly as far as their heavy fighters...

The result of trying gives you F-16s with conformal tanks and needing inflight refuelling and under wing tanks all the time.

F-16 is relatively cheap compared with other fighters actually.

Yeah, real cheap... tell Venezuela and Iraq how cheap they are...

The F-5 was cheaper because it did not have a lot of things. Like, it had no radar, or a primitive radar at best.

Cheap and simple go together... you can't have one without the other.... example F-35.

The F-20, if you wanted one, would have to be brand new. That made it horribly expensive to acquire.

The F-20 was too expensive for the customers who already had F-5s.... why do you think that is a contradiction to what you said?

The F-16 was probably the most successful fighter in sales in those two decades.

A lot of offers they could not refuse though... here is 1 billion in US military aide... what sort of US military fighter plane are you going to spend it on... no you can't spend it on anything else...

The Mirage was the best prior to that. Before that the MiG-21. Notice anything common among these aircraft?

There are no cheap simple single engined fighters any more?

And don't say Gripen... it is not that cheap and with all the American parts too subject to sanction anyway.

If anything the F-5 is the exception to the rule. It proves it can be done but without mass production and attention to making it cheap to manufacture and operate as a design point it won't happen.

The MiG-21 is still in use you know?

You can see today the Gripen as a single engine fighter which allegedly has low cost of operation which has managed to have relative sales success even with the US and other HATO nations giving 2nd hand F-16s. But they still need to be creative with their sales methods like leasing aircraft. Otherwise they can't compete with 2nd hand F-16s with a low acquisition cost even if it supposedly costs less to maintain.

Politics will kill Gripen sales.... anyone who can afford it and can get permission from the US for the engines and other parts will likely be offered F-16s for a much better price... and sanctions if you pick Gripen instead.

The performance of the Gripen seems to rule it out anyway...

There is and has been talk in the AF and government of such a plane for ages, as well as previous programs like the LFI. You have actually no proof they don't have interest, just your opinion.

The only single engine aircraft they operate are the Yak-152, and An-2... and drones.

This is exactly what they are doing. A light A2A focused fighter is going to be similar be it manned or not, so you create the two versions and get the best return of the investment. It is smart.

The Su-57 and S-70 pairing is a twin and single pairing... why not continue that success and have a twin and single manned LMFS coupling too?

No long range but decent range.

They have long range fighters.... why handicap your lighter fighters by demanding design and weight increases to extend range... another factor that screwed the F-35...

What is all this aggressive shit?

In design there has to be compromise... everyone wants good range, but you also want light weight and simplicity, but then you need capability or there is no point if it dies in the first 30 seconds of any fight.

You say you want light weight and single engines and canards but you want a light weight plane with the performance and range of a medium but you don't want a medium you want a light to keep costs down.

I wonder why I find it frustrating to convey this to you when you clearly already know it...

Design is all about compromises but your design choices don't match your claimed design goals.

If you do not differentiate a strike platform from a fighter you have a problem Garry. It should be pretty obvious what purpose the S-70 serves.

If you think a 5th gen fighter and its 5th gen drone is only capable of one sort of mission then you have the problem.

5th Gen fighters are described as omnirole fighters... not multirole where it can be loaded up for any mission you choose, but omnirole, which means an Su-57 loaded up with AAMs can fly with two S-70 drones equipped with long range SEAD weapons and two more drones armed with strike weapons like guided glide bombs and they can all take to the air and fly together and deal with enemy radar and enemy ground targets and enemy aircraft in one mission, but if you think the S-70 can only carry a guided bomb like some Russian F-117 then that is OK too.

Change light by medium and you are right. Big AFs use the heavy fighters to guarantee performance and complement them with light ones for numbers, it is countries with lesser air forces that have to rely on a compromise solution in form of medium fighters which are normally neither as capable as heavy ones nor as cheap as the light ones.

Countries can buy any types their suppliers allow... just look at Flanker sales to see that...

Not a purpose built A2A platform, by any stretch of the imagination.

Why would you think a drone designed to operate with a 5th gen heavy fighter would only have one mission type... launching R-77s and R-37s hardly requires super manouver performance... altitude is normally what it needs most along with any speed you can manage, but its flight range requirements mean supersonic speed become less useful...

Are you joking? The Harrier was a mess and the F-35B is simply on another category. Do yourself a favour and take a look at the specs please...

The specs came from the same marketing department that said it was stealthy and its job would be to fly over S-300 and S-400 missile sites and drop cheap guided bombs to destroy them. The Harrier on the other hand has seen some combat and in terms of air to air wasn't half bad... though as I have probably mentioned before an F-4 Phantom would have been better in terms of air to air weapons and speed and ability to defend a fleet of ships.

I notice you question Rostec because it has no government money, but now you say the government was wrong when they wanted STOVL. Either way, who disagrees with you is wrong, be it government, Rostec or whoever. OK I get it.

A government doesn't know what it wants... they get told all sorts of shit like after WWIII starts the only aircraft flying will be VSTOL because all the runways will be destroyed. VSTOL fighters are brilliant because they can take off from anywhere so you can locate your airfields right up near the front line so a VSTOL fighter can be on target in 5 minutes and will be on call all the time because it will be so close to the fighting... any 20 square metres of highway ashphalt will do to operate from, while a conventional aircraft might operate 100km away and take half an hour to get to the combat area to support the troops.

In urban combat your VSTOL fighters could operate from supermarket carparks and enemy fighters will be gone because after 5 hours all the airfields will be gone so even if they are not shot down they wont be able to operate.

We know it is bollocks now because they tested it and found it was bollocks... VSTOL aircraft are fragile and terribly prone to damage... their side mounted engine nozzles attract even the shittiest and most useless MANPADS like SA-7A and Redeye that normally wont lock on anything except the tail end of aircraft they are not fast enough to catch... but they can catch hovering VSTOL fighters...

Supermarket carparks are horrendous places for FOD... plastic bags in particular but any old rubbish will ruin the best and most expensive engine in a second.

We know the Russian government had a requirement for another stealth aircraft... we know that contract was delayed until the PAK FA went in to serial production and we know that has now happened.

This report suggests to me that in addition to the LMFS project that Rostek want to make a light plane, with the view to perhaps achieving all your proclaimed ideals and selling it internationally... if this was the LMFS programme then what is the point in making this announcement... they already have the contract and should now be getting the funding... I rather suspect that this is something different that they might want to piggy back on the existing LMFS project but make it lighter and for export and then if it does work out cheaper and simpler they might sell this to the government instead, but this news is perhaps for India and for Turkey and perhaps even Brazil to say... do you want do you want to get in at the ground level of a new affordable fighter that wont be super stealthy but will be competitive perhaps even against medium 4th gen fighters... that is cheaper to operate than the Su-57 and F-35 if the latter is even an option...

some like Turkey will have their LHD and soon will have no planes for them. Plus Russia plus China it justifies, I think, the development, considering it is just a version of a plane you are going to design either way.

You are suggesting Russia should take on the burden and cost of making their new lighter 5th gen fighter a VSTOL fighter because Turkey might buy it and China might buy them too? And when China orders two and Turkey waits till development is finished and decides it is too expensive so they will just make drones instead, how is Russia going to feel having screwed up the design of its lighter 5th gen fighter to pander to the needs of other countries that don't give a shit?

I have seen programs with a way worse business case for sure.

But the scary thing is that the business case for the F-35 is actually much better than for this because the US has the money to piss away on it and the control of the allies to force them to buy this shit... something the Russians can't and wouldn't do anyway.

This allows to improve the UDKs and gives them a bit more of capability so your fleet can take care of more missions and your carriers are not tied to almost trivial roles like avoiding provocations on low intensity conflicts.

No it doesn't... it dilutes the capacity of the UDKs by removing space for helicopters and armour and ground troops, so they can carry shit planes with short range and limited performance but lots of space for the fuel they will waste and the ordinance they will need to operate with.

It makes rather more sense to not bother with Harrier type support and stick with F-14D like support with bigger better aircraft... Su-57s.

VKS sees no problem in having both fixed and rotary wing aircraft, contrary to what you argue.

They have never bothered with rotary wing fighters like the Ka-52K is... if they expect a new model Harrier on the way why bother?

I am sure the command will know when a carrier is needed. Some assets with good A2A capability on board an UDK just raise the bar against provocations and gives better capability overall. VMF is not going to have that many carriers to park them everywhere.

Anywhere there is a UDK operating outside of Russian ground and air based support it will likely also have a few cruisers and at least a carrier...

You are faster to be dismiss than to understand it seems.

No... please continue to waste your time telling me how you are going to polish this turd... maybe just freeze it solid and the surface ice crystals reflecting the light will make it appear to be shiny...

I have not reduced the size of any of those, even when it could be actually done. The further you move the lift fan to the front, the longer its torque arm and therefore it will be able to balance the plane with less thrust, that means, you can produce a bigger portion of the total lifting thrust at the main engine and make the frontal propulsion assembly smaller. That is a main limitation of the F-35, look how far forward the main engine was brought in order to be able to balance the plane.

So if you make the front and rear extended out further... by say 500 metres, then by that logic you just need a very small spring to keep the plane in the air... right?

That sarcasm is just showing you don't understand a bit of what is proposed here, and that is sad.

What... a UCAV doesn't need a cockpit, but moving the fan forward improves the design you say so swap the cockpit for the fan and then replace the cockpit with an extra fuel tank and you are done...

I wonder what the specs are for using an electric hybrid set of lift fans for a VTOL plane. Its pretty obvious that future jet fighters will need a lot more electrical capacity for lasers, EM cannons etc. What would the weight be for a 25,000 KWH generator and 2x 12000 HP electric lift fans? You will eliminate the gearbox and shaft. Could a flying wing fighter work using lift fans to augment manuverability? So many cool options.

Azipods as used on ships would allow rotating fans taht can be used for vertical takeoff and horizontal flight so lift engines don't simply become dead weight during normal flight... the use of four engines... two electric at the front that just shift air without fuel being added so cold air, while the two jets at the rear that can also be rotated could use jet fuel and run hot and provide electricity for the front engines... once you are airborne you could angle them back steadily to increase forward flight speed and take the lift requirements from the engines onto the wings and in full forward flight all four engines can operate... in forward flight the front electric engines could suck air and blow it into the intakes of the rear engine to increase air flow speed through the bypass air ducts of the rear turbofan engines...

There are lots of clever things you could do...

GarryB wrote:
The Su-57 and S-70 pairing is a twin and single pairing... why not continue that success and have a twin and single manned LMFS coupling too?

LMFS and Su-57/S-70 could operate together too. And one manned LMFS could work with say two unmanned LMFS too. I guess it will depend on the mission now they are gaining so much flexibility with the new unmanned platforms. I see no need for twin and single LMFS.

They have long range fighters.... why handicap your lighter fighters by demanding design and weight increases to extend range... another factor that screwed the F-35...

The range in the F-35 came as a by-product of having a huge fat plane where more than 8 t internal fuel could be placed. Nowadays a good integral design (BWB) and modern materials allow to get very reasonable amounts of fuel for a range of ca. 2500 km on internals without severe overweight or degradation of the plane's capacities, in fact the need to make the fuselage big enough for the weapons bays works in favour of the fuel capacity, because the linear dimensions grow and internal space appears (bays below, tanks above). The sketch I did resulted in 6-7 t internal fuel for a 10 t empty weight fighter, funnily enough the study by Saab came to the same numbers. I saw it only after doing my own estimations.

You say you want light weight and single engines and canards but you want a light weight plane with the performance and range of a medium but you don't want a medium you want a light to keep costs down.

See above. As discussed previously, the internal weapon bays force the light 5G fighter almost in the category of 4G middle fighter. I still call it light, because the heavy fighters are also heavier and at ca. 20 t are essentially twice as big. Long range is good, period, and for the export market it can be actually one of the key issues. So reaching a compromise solution in that regard is quite acceptable I think.

The canard thing makes sense to me for a smaller fighter whose bigger advantage is going to be agility rather than raw kinematics, sensors, range or payload. So it putting the focus on maneuverability gives it an edge in some aspects of the combat even vs. generally more powerful aircraft, once it will have also advantages due to its weight being proportionally smaller for the same lifting surface. So it can be used complementarily to the heavy fighters and make it harder for the enemy to have a winning strategy both in terms of design philosophy and of tactics. It is just an approach as there can be many others. In fact if you see designs for the wind tunnel, you will see the same platform normally with different aero layouts, conventional, with canards etc.

I wonder why I find it frustrating to convey this to you when you clearly already know it...

Design is all about compromises but your design choices don't match your claimed design goals.

Clearly I don't agree that the design choices don't match the goals...

If you think a 5th gen fighter and its 5th gen drone is only capable of one sort of mission then you have the problem.

5G brings multifunctional avionics but aero is what it is. Okhotnik is not a fighter and will never be, there needs to be planes to take care of that role still. Therefore the Su-57 is not a subsonic flying wing with low TWR but a supercruiser with enormous maneuverability. Day and night in terms of aero design.

Why would you think a drone designed to operate with a 5th gen heavy fighter would only have one mission type... launching R-77s and R-37s hardly requires super manouver performance... altitude is normally what it needs most along with any speed you can manage, but its flight range requirements mean supersonic speed become less useful...

You cannot use it mainly as a fighter because it would always lose, simple as that. It cannot accelerate, climb, maneouver or run. It cannot impart the same energy to its missiles. It can defend itself to a certain extent, be used tactically to threaten other planes or be used as a help to intercept CMs and that is fine, but still fighters are needed.

The specs came from the same marketing department that said it was stealthy and its job would be to fly over S-300 and S-400 missile sites and drop cheap guided bombs to destroy them. The Harrier on the other hand has seen some combat and in terms of air to air wasn't half bad... though as I have probably mentioned before an F-4 Phantom would have been better in terms of air to air weapons and speed and ability to defend a fleet of ships.

Ok so we will decide on an individual basis what the plane can do and what not, given specs cannot be trusted?

We know the Russian government had a requirement for another stealth aircraft... we know that contract was delayed until the PAK FA went in to serial production and we know that has now happened.

This report suggests to me that in addition to the LMFS project that Rostek want to make a light plane, with the view to perhaps achieving all your proclaimed ideals and selling it internationally... if this was the LMFS programme then what is the point in making this announcement... they already have the contract and should now be getting the funding... I rather suspect that this is something different that they might want to piggy back on the existing LMFS project but make it lighter and for export and then if it does work out cheaper and simpler they might sell this to the government instead, but this news is perhaps for India and for Turkey and perhaps even Brazil to say... do you want do you want to get in at the ground level of a new affordable fighter that wont be super stealthy but will be competitive perhaps even against medium 4th gen fighters... that is cheaper to operate than the Su-57 and F-35 if the latter is even an option...

Maybe, but it is unlikely that they create two new planes, when the market for just one of them is far from obvious. And of course they have always made such announcements, more even if they relate to planes with a clear export potential. But we will see, maybe you are right.

You are suggesting Russia should take on the burden and cost of making their new lighter 5th gen fighter a VSTOL fighter because Turkey might buy it and China might buy them too? And when China orders two and Turkey waits till development is finished and decides it is too expensive so they will just make drones instead, how is Russia going to feel having screwed up the design of its lighter 5th gen fighter to pander to the needs of other countries that don't give a shit?

Unless you get Russia to work like US, a market works exactly like you just described, yes.

But the scary thing is that the business case for the F-35 is actually much better than for this because the US has the money to piss away on it and the control of the allies to force them to buy this shit... something the Russians can't and wouldn't do anyway.

See above, free market sucks  

Anywhere there is a UDK operating outside of Russian ground and air based support it will likely also have a few cruisers and at least a carrier...

Obviously we do not agree here. There are low intensity deployments where the UDK will be the operations room, it has already been announced that those ships will take that role. So how do you justify it if there is going to be a carrier and associated fleet always by their side?

No... please continue to waste your time telling me how you are going to polish this turd...  maybe just freeze it solid and the surface ice crystals reflecting the light will make it appear to be shiny...  

I don't give a damn about the F-35, I just used the drawing to explain the idea of how an UCAV can actually be a viable STOVL fighter.

What... a UCAV doesn't need a cockpit, but moving the fan forward improves the design you say so swap the cockpit for the fan

Yes...

GarryB wrote:I am responding to the claim that single engined aircraft by definition are slimmer and more aerodynamic and don't need as much fuel or maintenance compared with a similar twin engined design.

GarryB wrote:
What loadout can an F-16 fly with having weapons only at 7.7 tons?

Like many aircraft someone has worked out the max weight ratings for all its weapon points and added them up, but achieving such a payload is simply not practically possible.

That is the rating of the hard points, yes finding a magic combo of exactly 7.7 T is unlikely

GarryB wrote:
This is the stupidity I am fighting against... you want a fighter to protect an area... extra range is nice but it comes at a cost in terms of weight and also drag... internal fuel is the best compromise because it does not increase drag but it sure does ruin that nice power to weight ratio you had as a fighter.

Having Flankers operating from one airbase does not mean it can cover the airspace 2,000km in any direction, while a Fulcrum operating from the same airfield only covers 1,000km radius... very simply in western Russia there are going to be other air fields and other units all over the place and the 2,000km radius circle around that Flanker airfield is going to serious overlap all the airfields nearby.

If there is a target detected 1,500km from your airfield you are not going to send an Su-35 to check it out... you are going to look at the closest airfield to the target which might be a Fulcrum airfield that is 300km away from the target and you are going to send them.

The Flanker might have the range to get there but it wont have the time... if you are going to buy Flankers and base all your military airfields 2,000km apart then any idiot can map a flight path that goes between them so launching flankers all the time but to reach the target before it goes past they will have to go supersonic which means their 2,000km range flight radius just became a 1,000km flight radius if you are lucky.

Thinking a Flanker can actually protect twice the volume of airspace is just bullshit... in fact having shorter ranged fighters is better because they wont get called away to do jobs thousands of kms away from what they are supposed to be protecting.

Its not stupidity, its Russian doctrine. The SU-35 has 11500 kg of fuel capacity, the MIG 31 13.4K kg. You only lose the power to weight ratio when your tanks are full, and if you are going on a long mission you tend to arrive at just over 1/2 fuel load, if not you take less. It also allows loiter capacity.  How often is power to weight needed? only in a close dogfight. How often does that happen? Ever seen an airliner do an airshow with no load and low fuel. 787 can pretty much zoom climb like an SU-35. You think all those brilliant SU-35 demos are done with 11.5K kg of fuel onboard? Also big tanks give planes loiter capability which is very valuable when supporting ground forces. Fuel delivered by tanker costs over $120/gallon.

GarryB wrote:

Russia doesn't need that bullshit... except a very rare one off ferry transfer with external tanks and inflight refuelling stops which could be airborne but could just as easily be air field landings too.

They have fighters to protect their bases and the surrounds and they have longer range fighters for longer ranged missions... they don't all need long range that is just dumb to expect lighter cheaper simpler fighters to be able to fly as far as their heavy fighters...

The result of trying gives you F-16s with conformal tanks and needing inflight refuelling and under wing tanks all the time.

WHy is it dumb, adding tankage at the point of design is inexpensive and adds flexibility. Based on trends most airplane designers seem to agree with this.

GarryB wrote:
And don't say Gripen... it is not that cheap and with all the American parts too subject to sanction anyway.

The Gripen is about 1/3 the cost to operate of F-16

As was already mentioned , why doesn't Russia build a JF-17 of its own ?

Give it the stealth treatment looks wise. It would be a good export to middle countries.

Edit: I missed the big news a couple days ago about the light fighter. I thought that was just the UAE/Russia deal from 2017.

Anyway I think they should build it the same size as the JF-17

Backman wrote:As was already mentioned , why doesn't Russia build a JF-17 of its own ?

Give it the stealth treatment looks wise. It would be a good export to middle countries.

Edit: I missed the big news a couple days ago about the light fighter. I thought that was just the UAE/Russia deal from 2017.

Anyway I think they should build it the same size as the JF-17

There is quite a bit of size and weight creep from 4th to 5th gen fighters, you can check this for yourself looking at the planes of the different generations. A good example is Saab's Gripen vs. FS2020, which are almost identical in approach and role but differ substantially in weight. Placing weapons internally has some serious implications and modern avionics even when compact are very complex, plus the need to carry internally the fuel plus the extra weight of LO/VLO design. So I think the JF-17 is a bit too small to be a proper 5G plane as it is normally understood

LMFS wrote:

There is quite a bit of size and weight creep from 4th to 5th gen fighters, you can check this for yourself looking at the planes of the different generations. A good example is Saab's Gripen vs. FS2020, which are almost identical in approach and role but differ substantially in weight. Placing weapons internally has some serious implications and modern avionics even when compact are very complex, plus the need to carry internally the fuel plus the extra weight of LO/VLO design. So I think the JF-17 is a bit too small to be a proper 5G plane as it is normally understood

I mean they should just make it look 5th gen. But make it light, 1 engine and simple. Basically no different capabilities wise than the JF-17.

BTW this was a pic used in one of the blogbeforeflight article. Not sure where it came from

LMFS and Su-57/S-70 could operate together too.

I don't think that would make sense... essentially the S-70 acts as an LMFS would, but ironically the S-70 with its 5,000-6,000km range probably would have good flight endurance to operate with the Su-57, while the LMFS likely would not.

I would think a scaled down S-70 could be used with the LMFS to provide the support it might need and perhaps Su-35s and Su-30s as well with the Flankers acting as mini AWACS with the stealthy smaller LMFS operating closer to the enemy using its sensors passively...

And one manned LMFS could work with say two unmanned LMFS too. I guess it will depend on the mission now they are gaining so much flexibility with the new unmanned platforms. I see no need for twin and single LMFS.

An unmanned LMFS will likely be too expensive to be a drone even with just one engine. I would think LMFS will be a twin engined manned aircraft and the drone it operates with will be a flying wing single engined type like S-70 but smaller and cheaper.

The range in the F-35 came as a by-product of having a huge fat plane where more than 8 t internal fuel could be placed.

But making it fat has made it a slug... having internal volume for lots of fuel is making the best of a bad situation... it would be better if it was a bit short on range but accelerated super fast with low drag and high supercruise speed...

Long range is good, period,

So a 200 ton light fighter is acceptable because all that fuel means it has good range... it flys like a dog and corners like an overweight and pregnant hippo... but it can go for ever... and that is what you think is important.

The canard thing makes sense to me for a smaller fighter whose bigger advantage is going to be agility rather than raw kinematics, sensors, range or payload.

So Canards fix everything... yeah, I heard you.

Okhotnik is not a fighter and will never be, there needs to be planes to take care of that role still.

Arguably an F-35 is not a fighter either... it is a platform that carries around missiles and a radar... the S-70 can carry internal and external weapons including AAMs like self defence short range ones and very long range ones like the R-37M and likely also its replacement... remind me again why it would be a bad fighter?

Therefore the Su-57 is not a subsonic flying wing with low TWR but a supercruiser with enormous maneuverability. Day and night in terms of aero design.

It operates with the Su-57... why would both need to turn and burn? Besides with the potential for TVC the S-70 without onboard crew could be capable of astounding manouver performance for all we know.

You cannot use it mainly as a fighter because it would always lose, simple as that. It cannot accelerate, climb, maneouver or run. It cannot impart the same energy to its missiles. It can defend itself to a certain extent, be used tactically to threaten other planes or be used as a help to intercept CMs and that is fine, but still fighters are needed.

You say that but does it make it true?

A flight of S-70s and Su-57s are patrolling Russian border territory and a target appears... the target is 150km away and has opened fire... lets say it has launched four Meteor missiles... the S-70 carrying R-37Ms might then climb and accelerate and seriously close distance on the target and then launch weapons at the target while the Su-57s turn and head off on a tangent direction while monitoring what the S-70s see with their radar and sensors... as the S-70s get closer they might start launching R-77s at the Meteors already fired and then R-73s as they get closer while making sure their R-37s are on target in case of any manouvers by the target... but no hang on... someone on the internet said a fighter has to be able to accelerate and climb like a rocket and pull 10g till the pilots eye bleed... well if that is true then F-35 pilots are fucked.

Ok so we will decide on an individual basis what the plane can do and what not, given specs cannot be trusted?

The M1A1 Abrams was invincible till it came up against weapons developed after then 1970s... the F-117 was invisible... till it wasn't...

Maybe, but it is unlikely that they create two new planes, when the market for just one of them is far from obvious.

They will most likely be conservative for the LMFS for the Russian AF, so two engines in the 12 ton thrust range... perhaps they will talk to Turkey or China or India about a single engined model to be a cheaper aircraft that can be produced in larger numbers, but the requirements of stealth will probably demand production precision beyond what they can manage while keeping it cheapish.

Unless you get Russia to work like US, a market works exactly like you just described, yes.

The Russian MIC works for the Russian military first... there are very few things intended for export only like Saiga rifles etc...

The exception is when a foreign country ponies up the cash to make the product like the Pantsir... and the RPG-32...

See above, free market sucks

Not really... it just means it will remain talk... like the JSF programme should have...

Obviously we do not agree here. There are low intensity deployments where the UDK will be the operations room, it has already been announced that those ships will take that role. So how do you justify it if there is going to be a carrier and associated fleet always by their side?

I would define low intensity as being a conflict where fighter aircraft are not needed at all and Ka-52s with R-77s would be enough to deal with any air threats...

Hardly a reason to spend 20 billion dollars to develop a 5th gen VSTOL fighter for...

I don't give a damn about the F-35, I just used the drawing to explain the idea of how an UCAV can actually be a viable STOVL fighter.

But you already said UCAVs can't be effective fighters...

Its not stupidity, its Russian doctrine. The SU-35 has 11500 kg of fuel capacity, the MIG 31 13.4K kg. You only lose the power to weight ratio when your tanks are full, and if you are going on a long mission you tend to arrive at just over 1/2 fuel load, if not you take less. It also allows loiter capacity. How often is power to weight needed? only in a close dogfight. How often does that happen? Ever seen an airliner do an airshow with no load and low fuel. 787 can pretty much zoom climb like an SU-35. You think all those brilliant SU-35 demos are done with 11.5K kg of fuel onboard? Also big tanks give planes loiter capability which is very valuable when supporting ground forces. Fuel delivered by tanker costs over $120/gallon.

We are talking about a 5th gen LIGHT multirole fighter... not a MiG-31 interceptor or a Su-35 long range fighter.

When long loiter time is needed use a bigger plane.

We are talking about a submachine gun and you demand it reach the same distance as an assault rifle or it is no good... they already have the Su-57 and S-70, they don't need another one.

WHy is it dumb, adding tankage at the point of design is inexpensive and adds flexibility. Based on trends most airplane designers seem to agree with this.

Perhaps I am not explaining myself properly... I am the one suggesting a slightly larger "light" 5th gen fighter with twin engines... and decent performance... it is other members that are suggesting small and super light single engined possibly vertical take off planes of the smallest size and lowest cost is the solution.

Apparently making a plane smaller and also fitting only one engine increases its flight range and makes it super cheap... you know... like the F-35 did.

The Gripen is about 1/3 the cost to operate of F-16

And for the tests by Finland was found to be so short on capability compared with the F-18 and the Typhoon and the Rafale that they were not going to consider it. Saab resorted to suggesting it could be the low fighter in a high low mix so its lack of usefulness wont be as much of an issue, but Finland realised a dog when they saw it... even if its operational costs is zero if it can't do the job it is worthless.

As was already mentioned , why doesn't Russia build a JF-17 of its own ?

Because Russia is more interested in something that is capable and can actually do the job rather than something that is just cheap... which is why they are waiting for MiG-35s instead of just putting MiG-29M2s in mass production.

Anyway I think they should build it the same size as the JF-17

They could use such a fighter on the border of Mongolia, but not that many other places...

The Su-25TM would probably make more sense...

BTW this was a pic used in one of the blogbeforeflight article. Not sure where it came from

If it has no air intakes under its wing then as soon as it pulls a high AOA manouver the engine will stall and it will be in trouble... if it has air intakes above and below the blended wing/fuselage then that would be bad for RCS...

Maybe a swinging door that closes the lower air intake during takeoff and during normal flight and shifts up to seal the upper intakes during high positive g manouvering... or perhaps sits in the middle and allows upper and lower intake suction for more AB power during manouvering...

GarryB wrote:
I don't think that would make sense... essentially the S-70 acts as an LMFS would, but ironically the S-70 with its 5,000-6,000km range probably would have good flight endurance to operate with the Su-57, while the LMFS likely would not.

Who says they need to fly hand in hand? The Su-57 will cover much more territory than the LMFS, and the S-70 with huge range and completely different parameters will go deep into enemy territory where the Su-57 maybe will not go or fly twice as long. The Okhotnik cannot keep pace with the Su-57 when it is time to fly fast or accelerate, and so on. They are resources that will be called and coordinated according to the task. Russia is making constant announcements about their battlefield management systems and the increasing coordination of all assets.

I would think a scaled down S-70 could be used with the LMFS to provide the support it might need and perhaps Su-35s and Su-30s as well with the Flankers acting as mini AWACS with the stealthy smaller LMFS operating closer to the enemy using its sensors passively...

The LMFS can operate closer to the front and close gaps, exactly as you have said several times before. It simply will not have the persistence to stay on station as a Su-57 will do, it will be tasked with shorter, clearly targeted missions.

An unmanned LMFS will likely be too expensive to be a drone even with just one engine.

This is similar to myself saying twin engine cannot be cheap, it is our opinion. I don't see why an unmanned LMFS cannot be cheap, or to be more specific, what are the elements a smaller UCAV would spare? None, as far as I see it. If you want to be able to carry say 4 AAMs or 2 pieces of A2G ordnance internally you need a size which is already roughly 10 t empty. Smaller UCAVs will carry smaller weapons and can used too, but I didn't get the memo that says weapons like the ones current fighters carry are obsolete.

I would think LMFS will be a twin engined manned aircraft and the drone it operates with will be a flying wing single engined type like S-70 but smaller and cheaper.

I don't think I will ever understand your alergy to single engine fighters but who knows, if you read what Chemezov says, he mentioned light and medium sized fighter and their requirements and characteristics. This means that at least they contemplate different options but could even mean they intend to create several platforms. Maybe the Skat has a place there too? I don't know. But I don't think it makes sense for MiG to replicate the same that Sukhoi did, only in their own, smaller version. Synergy comes through the confluence of different approaches and not by duplication of efforts. That means, MiG needs to understand that there is no need for them to do over again what Sukhoi already has done, even if that means missing all the important know-how Sukhoi got. I am sure VKS will have their say and not allow companies to act just in their own interests.

But making it fat has made it a slug... having internal volume for lots of fuel is making the best of a bad situation... it would be better if it was a bit short on range but accelerated super fast with low drag and high supercruise speed...

Actually the F-35 design is quite decent, as far as you stay subsonic and concentrate on strike missions. It accelerates quite well and turns decently, it has good nose pointing capacities. It has very good range (for its size) and good payload, also for its size. The problem is when they try to market it as an universal tool and an air superiority fighter, which it is clearly not. There are some guys on the net that really lose their sh*t over it and see it dominating anything at will and assume it fighting will be like playing videogames with God mode on, invisible and all knowing. Such has been the propaganda to force allies to use the F-35 as their main A2A asset, when it should have just remained a strike fighter.

So a 200 ton light fighter is acceptable because all that fuel means it has good range... it flys like a dog and corners like an overweight and pregnant hippo... but it can go for ever... and that is what you think is important.

Don't take things out of context, every design has its compromises between different characteristics you value, and there will be overlapping between what you call a medium fighter and what I call a light one. You clearly use exaggerations but you do not mention the actual design decisions I propose, because obviously they are not ridiculous or far fetched, they are quite coherent and logical in fact. 10 t empty, 6 t fuel, bays for 2 A2G ordnance + 2 MRAAM, one engine with ca. 10 tf dry / 15 tf wet. What is so ludicrous, tell me.

So Canards fix everything... yeah, I heard you.

The canard allergy is also something I dont understand. I like the Su-57 very much and it has no canards...

Arguably an F-35 is not a fighter either...

Is a strike fighter, while the Okhotnik is no fighter at all.

It operates with the Su-57... why would both need to turn and burn?

Three times less thrust, similar weight. No supersonic flight, no surface controls for high AoA, no strong longitudinal authority, dorsal intake that chokes when turning, no afterburner... should I continue?

 Besides with the potential for TVC the S-70 without onboard crew could be capable of astounding manouver performance for all we know.

See above. And the model of the definitive Okhotnik had a flat nozzle.

You say that but does it make it true?

Even worse, physics

A flight of S-70s and Su-57s are patrolling Russian border territory and a target appears... the target is 150km away and has opened fire... lets say it has launched four Meteor missiles... the S-70 carrying R-37Ms might then climb and accelerate and seriously close distance on the target and then launch weapons at the target while the Su-57s turn and head off on a tangent direction while monitoring what the S-70s see with their radar and sensors... as the S-70s get closer they might start launching R-77s at the Meteors already fired and then R-73s as they get closer while making sure their R-37s are on target in case of any manouvers by the target... but no hang on... someone on the internet said a fighter has to be able to accelerate and climb like a rocket and pull 10g till the pilots eye bleed... well if that is true then F-35 pilots are fucked.

The Okhotnik will not be able to close in onto the attackers, that will dance in circles around it. It will spend its ammo shooting down AAMs. Employing it as you say makes little sense.

The M1A1 Abrams was invincible till it came up against weapons developed after then 1970s... the F-117 was invisible... till it wasn't...

I don't buy the hype, but I have to work with specs in public domain. So if they say the engine gives 40,000 lb thrust and I see it possible and consistent with the performance I see from the plane, yes, I will take it. Maybe not with 100% trust but what else can we do?

They will most likely be conservative for the LMFS for the Russian AF, so two engines in the 12 ton thrust range...

Why two newly developed engines would make more sense than one already existing engine like izd. 30? 2 x 12 tf is the thrust of a Flanker... what use has the VKS for more planes like that and what would be the savings??

I would define low intensity as being a conflict where fighter aircraft are not needed at all and Ka-52s with R-77s would be enough to deal with any air threats...

You are deflecting the question.

But you already said UCAVs can't be effective fighters...

What??? They can be the best fighters. But they need to be designed for the role, unlike Okhotnik.

If it has no air intakes under its wing then as soon as it pulls a high AOA manouver the engine will stall and it will be in trouble...

Exactly, like Okhotnik.

Russia needs to evolve light fighters to enable future transition to automated drones. NATzO is doing this so Russia can't
sit and twiddle its thumbs. And Russia can afford such a development program even we are talking about tech that will
only arrive decades from now.

kvs wrote:Russia needs to evolve light fighters to enable future transition to automated drones.    NATzO is doing this so Russia can't
sit and twiddle its thumbs.   And Russia can afford such a development program even we are talking about tech that will
only arrive decades from now.

Do you agree with JF-17 light ? Or Mig 35 "light"

They could use such a fighter on the border of Mongolia, but not that many other places...

The Su-25TM would probably make more sense...

The minute you start making something bigger, it will end up taking 10+ years to develop. But a place like Mongolia is exactly where you'd sell them. A place like Armenia shouldn't have bought su 30's. But Russia doesn't have a product for these small countries.

Looks like lighter variants are the future if evolution into capable drones is going to happen. I am not sure anybody
knows what is the right size. Theoretically it does not matter. What matters is to give any drone the ability to
survive accelerations that no human would live through. That argues for different shapes and smaller frame to
enable ridiculous 90 degree turns and 180 degree course reversals. Drones would evolve towards AA missiles
to some extent. But then we get into a drone vs drone evolution race. But this is normal for weapons systems
and life itself.

GarryB wrote:

But making it fat has made it a slug... having internal volume for lots of fuel is making the best of a bad situation... it would be better if it was a bit short on range but accelerated super fast with low drag and high supercruise speed...

They could have made it a bit longer, making it wide was a design choice, probably caused by the need to combine a fan and weapons bay.

GarryB wrote:
So a 200 ton light fighter is acceptable because all that fuel means it has good range... it flys like a dog and corners like an overweight and pregnant hippo... but it can go for ever... and that is what you think is important.

MIG-31 has an MTOW of about 50T if there were reasons to build a 200T fighter I am sure it would be done. In fact the arsenal plane concept may result in a 100 T + fighter Maybe based on a C-17 or a B1B or the new US bomber.

GarryB wrote:

Perhaps I am not explaining myself properly... I am the one suggesting a slightly larger "light" 5th gen fighter with twin engines... and decent performance... it is other members that are suggesting small and super light single engined possibly vertical take off planes of the smallest size and lowest cost is the solution.

Apparently making a plane smaller and also fitting only one engine increases its flight range and makes it super cheap... you know... like the F-35 did.

F-35 is an extra special US ***uster I think we agree with that. Most of its problems are from the desire to combine VTOL and and standard planes. If you look at F15 and F16, there is a much better example of single and twin engine economics.

GarryB wrote:

And for the tests by Finland was found to be so short on capability compared with the F-18 and the Typhoon and the Rafale that they were not going to consider it. Saab resorted to suggesting it could be the low fighter in a high low mix so its lack of usefulness wont be as much of an issue, but Finland realised a dog when they saw it... even if its operational costs is zero if it can't do the job it is worthless.

I assume you mean Switzerland, Gripen actally won the first contest, the second contest the Swiss (probably bribed by the USA) insisted they would only consider in service planes so the Gripen E was excluded. The Finnish HX program is still ongoing. By many accounts the Gripen E is like a mini F-18 Growler in capabilities.
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