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    Post  George1 on Sun Sep 30, 2018 11:10 pm

    i dont think that there is official project for LMFS development, just proposed
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    Post  GunshipDemocracy on Mon Oct 01, 2018 12:24 am

    George1 wrote:i dont think that there is official project for LMFS development, just proposed


    I second that, however I think that technical/conceptual work on LMFS has never officially been stopped. I am also convinced that VSTOL fighter is not going to be deck version only, but in fact will be LMFS implementation.
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    Post  LMFS on Mon Oct 01, 2018 12:28 am

    GunshipDemocracy wrote:There were long time rumors about MiG working on new light fighter (call if  LMFS if you prefer). Long time ago I remember an interview wti Pogosyan about Sukhoi. In his cabinet was little mode of fighter. Strikingly similar to Su-57... it was long ago before any official shape was shown.

    Do you remember 2017 Butowski's drawing?  


    or Yak-201 proposal ?  of course no relation Twisted Evil Twisted Evil Twisted Evil  
    Delta-canard is a very good aerodynamic configuration for a fighter, no wonder there have been so many studies and proposals incorporating it. It does not mean there is nothing real going on about them. Just look below for some samples from US, with end result ZERO production models with canards:

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    Swedish 5G proposal is completely analogous to interpretations of LMFS until now:

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    Having said that, I can imagine MiG doing all they can to push such project forward, making proposals to MoD and studying all the possible configurations so if the project is approved they can be as advanced as possible. And I can also figure they would use the lessons from MFI project.
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    Post  GunshipDemocracy on Mon Oct 01, 2018 1:04 am

    LMFS wrote:
    Delta-canard is a very good aerodynamic configuration for a fighter, no wonder there have been so many studies and proposals incorporating it. It does not mean there is nothing real going on about them. Just look below for some samples from US, with end result ZERO production models with canards:

    True but is also structurally unstable and perhaps less stealthy. Any configuration is a trade off between constrains and military requirements. Perhaps US doctrine assumed stealth over maneuverability? look at F-35.

    But Russia can have other requirements to light fighter like agility (remember drone mode where 9+ g is not a restriction) over stealth?


    Having said that, I can imagine MiG doing all they can to push such project forward, making proposals to MoD and studying all the possible configurations so if the project is approved they can be as advanced as possible. And I can also figure they would use the lessons from MFI project.

    Im not sure if MiG will be pushing anything now. There is only OAK now with MiG/Sukhoi or Yak. Borisov in turn said that there will be a design team consisting of experts from all of design bureaus. But I am sure that all experiences will be carefully studied (Migs/Yaks/Su's)
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    Post  LMFS on Mon Oct 01, 2018 1:34 am

    GunshipDemocracy wrote:True  but is also structurally unstable and perhaps less stealthy. Any configuration is a trade off between constrains and military requirements. Perhaps US doctrine assumed stealth over maneuverability? look at F-35.

    But Russia can have other requirements to light fighter like agility (remember drone mode where 9+ g is not a restriction)  over stealth?
    Yes, Russia can see it otherwise, MFI was delta-canard. European countries also decided for canards. Do not know why US favoured conventional tail, maybe to reduce risks associated to new technology? Su-57 is also "almost" conventional but its LEVCONS have some functions of the canard so it has is actually many of the best things of both solutions, plus TVC. Canard creates lift instead of detracting from it during turning and also if used in close-coupled configuration helps attaching the flow to the wing at high AoAs. So it is specially useful if you are interested in manoeuvrability. It will also help trimming in supersonic flight. Instability issues with the canard are not really an issue any more in the era of unstable-designed planes.
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    Post  GunshipDemocracy on Mon Oct 01, 2018 2:27 am

    LMFS wrote:
    Yes, Russia can see it otherwise, MFI was delta-canard. European countries also decided for canards. Do not know why US favoured conventional tail, maybe to reduce risks associated to new technology? Su-57 is also "almost" conventional

    id say:
    Su-57 - stealth
    Eurogfightet/Rafale/Grippen not stealth




    but its LEVCONS have some functions of the canard so it has is actually many of the best things of both solutions, plus TVC. Canard creates lift instead of detracting from it during turning and also if used in close-coupled configuration helps attaching the flow to the wing at high AoAs. So it is specially useful if you are interested in manoeuvrability. It will also help trimming in supersonic flight. Instability issues with the canard are not really an issue any more in the era of unstable-designed planes.

    I'd say delta should be considered additionally. Many advantages. First of all - lading/stall speed. Mind deck fighter.
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    Post  LMFS on Fri Oct 05, 2018 2:20 am

    Just wanted to share the results of some thoughts on a possible 5G light fighter layout. This is just for fun (no aerodynamic design!) but I found it very instructive to actually do the exercise of trying to house the main components such a plane would need in a (IMHO) sensible way and see the results.

    Characteristics:
    Length/height/wingspan 15.4 / 3.60 / 9.65 m
    Cross-sectional area 5.3 m2
    Wing surface 48.2 m2 + close-coupled canard. Additional elevators between the all-moving tails (MFI type)
    Fuel capacity (gross value since space for cannon, structure, piping, cabling, etc. are to be subtracted) > 6900 kg
    Engine sized according to AL-41
    Capture area of intake 0.92 m2 (equal to Su-57)

    This would be a multi-role, light 5G fighter made mixing ideas from F-16, MiG-29, Eurocanards/Lavi and MFI/Himat mainly. The idea would be to make it versatile (due to export requirements mainly) with focus on A2A performance, decent range and capacity to carry big A2G ordnance internally. So more a 5G F-16 than a F-35. This is clear considering the cross sectional area much closer to the first than to the second. It would use the same engine that Su-57 uses for cost reduction and hence should have an empty weight below 10 tonnes in order to keep a similar performance

    Weapon's bays would be the following:
    Ventral for 2x AGM or 4xMRAAM
    Side for 2 x MRAAM or reconnaissance / AEW equipment
    Wing roots for 2x SRAAM (Su-57 type)
    Admittedly clearances are really tight and is supposed all missiles have folding wings.
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    Post  GunshipDemocracy on Fri Oct 05, 2018 4:48 am

    LMFS wrote:Just wanted to share the results of some thoughts on a possible 5G light fighter layout. This is just for fun (no aerodynamic design!) but I found it very instructive to actually do the exercise of trying to house the main components such a plane would need in a (IMHO) sensible way and see the results.

    cool stuff, thanks. respekt respekt respekt


    Well you are not so far for real designs - look at MiG 1.42 LMFS proposal. Perhaps you'd be good aerospace designer? only not of VSTOL fighters  lol1  lol1  lol1


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    Post  LMFS on Fri Oct 05, 2018 2:51 pm

    GunshipDemocracy wrote:cool stuff, thanks.  respekt  respekt  respekt

    Well you are not so far for real designs - look at MiG 1.42 LMFS proposal. Perhaps you'd be good aerospace designer? only not of VSTOL fighters  lol1  lol1  lol1
    Thanks Gunship for undeserved praise. Well who knows, now you say it, maybe a good STOVL layout is also an interesting challenge... some ideas coming to my mind hahaha!
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    Post  Hole on Fri Oct 05, 2018 5:19 pm

    I guess Russia would choose a plane with two engines.
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    Post  LMFS on Fri Oct 05, 2018 9:35 pm

    Hole wrote:I guess Russia would choose a plane with two engines.
    Last models are two engine, but before they used single engine for long time. Single engine is an important cost factor for several reasons:

    > Obviously half number of pieces in the engines plus reduced complexity due to ancillary elements. This have IIRC provoked more mishaps in F-15s than the engines themselves have provoked in F-16.
    > Light fighter with one engine of the kind used in heavy ones allows for scale economies and faster failure correction.

    There are nevertheless clear advantages of two engine approach:
    > Near calls in peace time operations mean for single engine fighters loss of the aircraft while two engine planes can be saved
    > Survivability in war time can be tricky to assess. Losing one engine for a plane that has two is not lethal, but what are the chances such impaired fighter has to make it back to the base? For an attack plane facing AA artillery like Su-25 two engines is a must, for a fighter it is not so clear to me.

    So I think in the end the decision is not black or white but a rational evaluation of cost savings against risks. And given the reliability of modern engines I don't think it is a taboo anymore to use single engine fighters.
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    Post  Hole on Fri Oct 05, 2018 10:06 pm

    With only one engine you could end up with something like the F-35. Huge, heavy engine without reserves for future development.
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    Post  LMFS on Fri Oct 05, 2018 11:23 pm

    Hole wrote:With only one engine you could end up with something like the F-35. Huge, heavy engine without reserves for future development.
    I don't think I agree

    F-35 "outgrew" its own airframe because of unreasonable requirements for strike capacity and STOVL. X-35 was less than 10 tones and ended as the F-35 between 13.4 and more than 15... without increasing the length of the plane. As a result of increased weight and drag, more performance is demanded from the engine than was thought and dynamic behaviour suffered. But in any case, further improvements are in the pipeline for the F-135 which will notably increase its thrust.

    So we have two separated issues I would say:
    > Two much cross sectional area and too much weight concentrated in the middle section of the plane due to unfortunate program development which impacted the air vehicle. So engine has to cope with increased requirements compared to original plans
    > Grow capability of the engine itself, which is unaffected by the above

    In fact, a bigger engine is (marginally) more efficient than a smaller one due to physics. And one intake is also more efficient than two. T/W can be kept in line with two engine aircraft. So single engine is no problem for future development capacity IMHO. But if you develop your light fighter into a bomb truck don't expect it to have very good dynamics, this is clear and is to be addressed with the proper requirements and design philosophy.
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    Post  GunshipDemocracy on Sat Oct 06, 2018 5:22 am

    Hole wrote:I guess Russia would choose a plane with two engines.

    That's also possible but can then costs and weight are going up.  IMHO main restriction here will be size and unit cost. If new fighter is going to be about MiG-29 size then 2 engines make sense. 2x176kN can lift nicely even fairly heavy fighter.




    LMFS wrote:
    GunshipDemocracy wrote:cool stuff, thanks.  respekt  respekt  respekt

    Well you are not so far for real designs - look at MiG 1.42 LMFS proposal. Perhaps you'd be good aerospace designer? only not of VSTOL fighters  lol1  lol1  lol1
    Thanks Gunship for undeserved praise. Well who knows, now you say it, maybe a good STOVL layout is also an interesting challenge... some ideas coming to my mind hahaha!

    Just make sure VSTOL looks in full glory lol1 lol1 lol1



    LMFS wrote:F-35 "outgrew" its own airframe because of unreasonable requirements for strike capacity and STOVL. {} As a result of increased weight and drag, more performance is demanded from the engine than was thought and dynamic behaviour suffered. But in any case, further improvements are in the pipeline for the F-135 which will notably increase its thrust.
    +++
    But if you develop your light fighter into a bomb truck don't expect it to have very good dynamics, this is clear and is to be addressed with the proper requirements and design philosophy.


    if VSTOL would be guilty then why CATOBAR F-35 is still same size? no the problem was to be all-in-one. Stealth, bomb truck, fighter, and carrier based. Take bomb truck and stealth out  and you have nice VSTOL fighter.




    In fa So single engine is no problem for future development capacity IMHO.

    one Su-57 engine has 18tons thrust (with AB). Then VSTOL should be really light. Can be but if naval fighter shall have more payload then 2x or 1 250Kn NK-32 is better.
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    Post  LMFS on Sun Oct 07, 2018 12:22 am

    GunshipDemocracy wrote:That's also possible but can then costs and weight are going up.  IMHO main restriction here will be size and unit cost. If new fighter is going to be about MiG-29 size then 2 engines make sense. 2x176kN can lift nicely even fairly heavy fighter.
    That is 2 x izd. 30, what kind of light fighter would need that??

    if VSTOL would be guilty then why CATOBAR F-35 is still same size? no the problem was to be all-in-one. Stealth, bomb truck, fighter, and carrier based. Take bomb truck and stealth out  and you have nice VSTOL fighter.
    Don't follow your logic.
    Agree that they mixed too many incompatible requirements in the program, but among them a relevant one is the STOVL. In fact many of them can be illustrated with the drawings above.
    > It forced the main engine forward, in order to contribute to the vertical lift. This in turn prevented to place weapon bays in front of the engine as it would be best. They go to the sides of the engine, with two negative effects: increasing cross sectional area and only managing to offer restricted carrying capability for big ordnance.
    > The presence of the lifting fan implies a very wide middle section of the plane, which badly affects performance of the plane due to increased weight and drag.
    > Also it prevents the best place of the plane to be used for weapons bays, since needs to be reserved for the vertical lift HW.

    So in fact I think the STVOL requirement hindered the F-35 the most.

    one Su-57 engine has 18tons thrust (with AB). Then VSTOL should be really light. Can be but if naval fighter shall have more payload then 2x or 1 250Kn NK-32 is better.
    We are talking about a light fighter, izd. 30 is ideal. The plane above would be ca. 10 tonnes or less empty, around 16-17 tonnes full fuel, 21-22 tonnes MTOW. No consideration of STOVL was done. BTW, what plane can do vertical take-off while fully loaded?
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    Post  GunshipDemocracy on Sun Oct 07, 2018 3:54 am

    LMFS wrote:That is 2 x izd. 30, what kind of light fighter would need that??

    +++

    We are talking about a light fighter, izd. 30 is ideal. The plane above would be ca. 10 tonnes or less empty, around 16-17 tonnes full fuel, 21-22 tonnes MTOW. No consideration of STOVL was done. BTW, what plane can do vertical take-off while fully loaded?

    None of VSTOL in Vmode yet. Technically i think it can be achieved, but unlikely will be implemented due to costs.  Value of such an approach for military could be  a start by half squadron vertically in sudden combat situations.

    BTW 250kN engine was already proposed for,  only STOL, Yak 43... also light fighter in Yak-41 class.



    BTW 1
    MiG-35 has empty weight 13,5tons and normal load  18,500kg, Thrust(with afterburner) x2 90kN. So with 2x 180kN could start vertically with MTOW

    J-39 Grippen has empty weight 8000kg, MTOW =16500kg. In this situation one  AL-41 izd 30 with 180kN could do the job.

    Of course J-39 size/weight category with izd 30 could start vertically even with normal weight and only STOL with MTOW.




    Don't follow your logic.
    Agree that they mixed too many incompatible requirements in the program, but among them a relevant one is the STOVL. In fact many of them can be illustrated with the drawings above.
    > It forced the main engine forward, in order to contribute to the vertical lift. This in turn prevented to place weapon bays in front of the engine as it would be best. They go to the sides of the engine, with two negative effects: increasing cross sectional area and only managing to offer restricted carrying capability for big ordnance.
    > The presence of the lifting fan implies a very wide middle section of the plane, which badly affects performance of the plane due to increased weight and drag.
    > Also it prevents the best place of the plane to be used for weapons bays, since needs to be reserved for the vertical lift HW.

    So in fact I think the STVOL requirement hindered the F-35 the most.

    Hmm US required an agile bomb truck with VSTOL  which is stealth. Project did not bring desired results.  And only VSTOL is guilty? F-35  is perfect example that you cannot have it all.
    External size/proportions  dont change comparing with A i C So why it should be a problem with VSTOL only?  


    If you focus on VSTOL and sacrifice payload and stealth there i nothing that prevents you to have a decent, maneuverable  fighter.  



    BTW 2 Did you see Yak-41? please compare cross sections of both before you say  very wide middle section of fighter please.  With 150kN engine (vs. 190Kn F-35)  could fly 1800km/h and on Farnborough was performing barrel rolls.  It was designed almost 25 years before F-35.  Smaller payload tho.

    Yak first flight was 20 years before F-35. With new engines and composites designing of a new VSTOL should bring much better results.
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    Post  LMFS on Sun Oct 07, 2018 3:57 pm

    GunshipDemocracy wrote:None of VSTOL in Vmode yet. Technically i think it can be achieved, but unlikely will be implemented due to costs.  Value of such an approach for military could be  a start by half squadron vertically in sudden combat situations.
    A threat that is so close that it cannot wait 5-10 minutes for the squadron to take off maybe doesn't need full tanks...

    BTW 250kN engine was already proposed for,  only STOL, Yak 43... also light fighter in Yak-41 class.
    Thrust of the engine alone says nothing, it is T/W that matters.

    BTW 1
    MiG-35 has empty weight 13,5tons and normal load  18,500kg, Thrust(with afterburner) x2 90kN. So with 2x 180kN could start vertically with MTOW
    Nein, 11 tones empty from what I have seen. What are your sources?
    An airframe designed for RD-33 cannot house AL-41 class engine...

    J-39 Grippen has empty weight 8000kg, MTOW =16500kg. In this situation one  AL-41 izd 30 with 180kN could do the job.

    Of course J-39 size/weight category with izd 30 could start vertically even with normal weight and only STOL with MTOW.
    Grippen A had empty weight of 6.6 tones, 8 tones is new E version. Again, engine is a F-414 in the size / thrust class of the RD-33, not the heavy fighter engines of the type F-100/AL-41
    From the data available, only plane with T/W close to 1 fully loaded would be Su-57

    Hmm US required an agile bomb truck with VSTOL  which is stealth. Project did not bring desired results.  And only VSTOL is guilty? F-35  is perfect example that you cannot have it all.
    External size/proportions  dont change comparing with A i C So why it should be a problem with VSTOL only?  
    I have explained my take on that above, was it not understandable?

    If you focus on VSTOL and sacrifice payload and stealth there i nothing that prevents you to have a decent, maneuverable  fighter.  
    You have managed to turn the LMFS discussion in yet another STVOL thread respekt
    You can have a morally "decent" plane, but it is going to be worse than if now vertical lift HW was present. This is how things are done now, with HW which is ADDITIONAL. If this can be avoided then we could discuss about STOVL not being inherently worse than CTOL in terms of performance. Until then, there is simply nothing to discuss, in our universe something is always > nothing. Logical contradictions are not a matter of point of view you know...

    BTW 2 Did you see Yak-41? please compare cross sections of both before you say  very wide middle section of fighter please.  With 150kN engine (vs. 190Kn F-35)  could fly 1800km/h and on Farnborough was performing barrel rolls.  It was designed almost 25 years before F-35.  Smaller payload tho.

    Yak first flight was 20 years before F-35. With new engines and composites designing of a new VSTOL should bring much better results.
    I had that in mind Gunship. Not an expert in Yak-141, but from what is known, Lockheed did take a look at it and the result was to substitute the direct thrust engines at the front (the obvious solution for small cross section) with a lifting fan that does not provoke hot air ingestion problems. This is not an easy problem to solve, especially when the plane descends and the vortexes naturally direct the hot air of the nozzles to the intake in the higher side of the plane BTW. So it was in all probability a design compromise considered necessary to ensure safe operation. Can a solution be found? Maybe but that is pure speculation, even beyond of what we normally do... Rolling Eyes
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    Post  Vladimir79 on Sun Oct 07, 2018 8:26 pm

    You can't have canards on a stealth fighter, it is antithetical to the entire concept.
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    Post  GunshipDemocracy on Sun Oct 07, 2018 9:37 pm

    Vladimir79 wrote:You can't have canards on a stealth fighter, it is antithetical to the entire concept.  


    Like J-20 or MiG-1.44?

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    Even for 6th gen fighters stealth is not a top requirement anymore. Anyway you can be only a bit less or a bit more visible. With canards and TVC you can have supa-maneuverability, especially drone mode where +9 is not restriction anymore.
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    Post  LMFS on Sun Oct 07, 2018 9:55 pm

    Vladimir79 wrote:You can't have canards on a stealth fighter, it is antithetical to the entire concept.  
    Why? There are many examples of LO or VLO designs with canards.

    From what I have seen, they have leading and trailing edges that need to be treated as those of wings in regards of scattering. Transition to the body needs to be done carefully (see for instance LEVCONS on Su-57 as an example) and FCS needs to take care of their deflections to minimize impacts on RCS. But other than that I don't really get what is the big issue... benefits to aerodynamics are substantial
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    Post  GunshipDemocracy on Mon Oct 08, 2018 2:48 am

    LMFS wrote:
    GunshipDemocracy wrote:None of VSTOL in Vmode yet. Technically i think it can be achieved, but unlikely will be implemented due to costs.  Value of such an approach for military could be  a start by half squadron vertically in sudden combat situations.
    A threat that is so close that it cannot wait 5-10 minutes for the squadron to take off maybe doesn't need full tanks...

    It can even wait hours but in 10 minutes US stealth missile flies 150km or US attack fighters 250?



    BTW 250kN engine was already proposed for,  only STOL, Yak 43... also light fighter in Yak-41 class.
    Thrust of the engine alone says nothing, it is T/W that matters.


    empty weight Yak-141 - 11,500kg, Since Yak-43 didnt have vertical lift engines could be around those numbers.





    MiG-35 has empty weight 13,5tons and normal load  18,500kg, Thrust(with afterburner) x2 90kN. So with 2x 180kN could start vertically with MTOW
    Nein, 11 tones empty from what I have seen. What are your sources?
    An airframe designed for RD-33 cannot house AL-41 class engine...

    Empty weight:Russian wiki,but I assume I was wrong and you're right as not many places repeat this wight.
    https://ru.wikipedia.org/wiki/%D0%9C%D0%B8%D0%93-35

    Масса пустого: 13500 кг - empty weight 13,500kg

    http://bastion-karpenko.ru/mig-35/ they say ~11,000kgs

    AL41, you're right but I was talking about a fighter of this size/weight category. Not MiG-35 as you cannot continue making only upgrades instead of designing new machines. .




    J-39 Grippen has empty weight 8000kg, MTOW =16500kg. In this situation one  AL-41 izd 30 with 180kN could do the job.
    Of course J-39 size/weight category with izd 30 could start vertically even with normal weight and only STOL with MTOW.
    Grippen A had empty weight of 6.6 tones, 8 tones is new E version. Again, engine is a F-414 in the size / thrust class of the RD-33, not the heavy fighter engines of the type F-100/AL-41
    From the data available, only plane with T/W close to 1 fully loaded would be Su-57 [/quote]

    then we potentially can imagine size of next gen deck fighter if 1 engine layout will be chosen. russia russia russia
    MTOW T/W=he he F-35 has with Al-41 T/W < 1




    Hmm US required an agile bomb truck with VSTOL  which is stealth. Project did not bring desired results.  And only VSTOL is guilty? F-35  is perfect example that you cannot have it all. External size/proportions  dont change comparing with A i C So why it should be a problem with VSTOL only?  
    I have explained my take on that above, was it not understandable?

    no, Yak design proves you're wrong it has no bulky profile, But Yaks were not optimized to be stealth bomb trucks as well as didnt have CTOL version.




    You can have a morally "decent" plane, but it is going to be worse than if now vertical lift HW was present. This is how things are done now, with HW which is ADDITIONAL. If this can be avoided then we could discuss about STOVL not being inherently worse than CTOL in terms of performance. Until then, there is simply nothing to discuss, in our universe something is always > nothing. Logical contradictions are not a matter of point of view you know...

    Hmm why do you assume always VSTOL has to be "additional" to CTOL?What about to build VSTOL only fighter?
    You really dont have to repeat ad nausea that you cannot have all. I was first to point that to you BTW lol1 lol1 lol1
    Not every time stealth or payload is most important. Speed or agility then is not necessarily worse than fighters of the same class.

    In 80s Harrier had 97kN engine, Yak-141 150kN, perhaps new one can have something close to 200kN. Regardless of this new light materials, new avionics do make difference.



    [quote This is not an easy problem to solve, especially when the plane descends and the vortexes naturally direct the hot air of the nozzles to the intake in the higher side of the plane BTW. So it was in all probability a design compromise considered necessary to ensure safe operation. Can a solution be found? Maybe but that is pure speculation, even beyond of what we normally do... Rolling Eyes [/quote]

    True we need to see what solution with new tech can be found. With new materials, computer control tech many old problems can be solved. New fighter will be 20 years younger then F-35...
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    Post  LMFS on Mon Oct 08, 2018 3:33 am

    GunshipDemocracy wrote:It can even wait hours but in 10 minutes US stealth missile flies 150km or US attack fighters 250?
    Not answered my question. No full tank needed, take off with light load and that's it.

    empty weight Yak-141 - 11,500kg, Since Yak-43 didnt have vertical lift engines could be around those numbers.

    Sorry no clue about Yak-43

    AL41, you're right but I was talking about a fighter of this size/weight category. Not MiG-35 as you cannot continue making only upgrades instead of designing new machines. .
    Wikipedia intoxicating even in Russian  lol1  lol1
    Examples show thrust values that technology allows for a given size of fighter with reasonable payload and range. You can theorize about heavy fighter class thrust on light fighter but it is not clear when this will be available. Progress is being made clearly as Su-57 shows.

    then we potentially can imagine size of next gen deck fighter if 1 engine layout will be chosen.  russia  russia  russia
    MTOW T/W=he he F-35 has with Al-41 T/W < 1
    You have an example above with all those considerations already made. Normally light fighters are slightly heavier than 50% of heavy ones and their MTOW is more than 200% of empty weight. So their T/W empty is normally slightly worse than heavy ones and T/W full substantially below 1. Nevertheless as said 5G engines allow for unseen performance in light fighters. And with good wing folding you would get great numbers inside a ship.

    no, Yak design proves you're wrong it  has no bulky profile, But Yaks were not optimized to be stealth bomb trucks as well as didnt have CTOL version.  
    Yak proves nothing because I was not talking about Yak but about F-35 with a different lift system  Rolling Eyes

    Hmm why do you assume always VSTOL has to be "additional" to CTOL?What about to build VSTOL only fighter?
    Care submitting any functioning alternative solution for supersonic flight? I am all ears, really.

    You really dont have  to repeat ad nausea that you cannot have all. I was first to point that to you BTW  lol1  lol1  lol1
    Not every time stealth or payload is most important.  Speed or agility then is not necessarily worse than fighters of the same class.

    In 80s Harrier had 97kN engine, Yak-141 150kN, perhaps new one can have something close to 200kN. Regardless of this new light materials, new avionics do make difference.
    It is you who repeat ad nauseam, because you are not listening. It doesn't matter how much thrust you have on the main engine if you cannot match it at the front. And that is where the complications and additional HW come into play.

    Like said, please submit a workable propulsion solution or stop claiming that a STOVL without downsides can be created. It is that simple if you want to win us over. Until then your claims will meet the same objections over and over...
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    Post  GunshipDemocracy on Mon Oct 08, 2018 4:06 am

    It doesn't matter how much thrust you have on the main engine if you cannot match it at the front. And that is where the complications and additional HW come into play.
    Like said, please submit a workable propulsion solution or stop claiming that a STOVL without downsides can be created. It is that simple if you want to win us over. .

    I'dont need to win you over as you over as none off us is an experienced aerospace engineer with turbojet specialization.   lol1  lol1  lol1  

    Of course VSTOL  is more complicated an has more weight if it didnt have VSTOL capability.
    I never said its not the case. Its not my point here.  

    It it more complex, is it heavier then without VSTOL and...  ?  dunno  dunno  dunno





    LMFS wrote:
    GunshipDemocracy wrote:It can even wait hours but in 10 minutes US stealth missile flies 150km or US attack fighters 250?
    Not answered my question. No full tank needed, take off with light load and that's it.

    one by one...of course. One per minute from 1 take off strop or catapult.



    AL41, you're right but I was talking about a fighter of this size/weight category. Not MiG-35 as you cannot continue making only upgrades instead of designing new machines. .
    Wikipedia intoxicating even in Russian  lol1  lol1

    Mikoyan LMFS - Page 10 24ep8w

    he must have been the author then, or bears  lol1  lol1  lol1




    Examples show thrust values that technology allows for a given size of fighter with reasonable payload and range. You can theorize about heavy fighter class thrust on light fighter but it is not clear when this will be available. Progress is being made clearly as Su-57 shows.
    +++
    Nevertheless as said 5G engines allow for unseen performance in light fighters. And with good wing folding you would get great numbers inside a ship.

    OK tell me now who kidnapped original LMFS and substituted some reasonable no-VSTOL-h8er?  Suspect  Suspect  Suspect



    Hmm why do you assume always VSTOL has to be "additional" to CTOL?What about to build VSTOL only fighter?
    Care submitting any functioning alternative solution for supersonic flight? I am all ears, really.

    Yak-41 was a flying example. It was designed as VSTOL only.
    JSF F-35 is a joint strike fighter not a fighter. So payload and stealth are top requirements here.
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    Post  LMFS on Mon Oct 08, 2018 2:36 pm

    GunshipDemocracy wrote:I'dont need to win you over as you over as none off us is an experienced aerospace engineer with turbojet specialization.   lol1  lol1  lol1  
    Yes you should try to convince me with good arguments, otherwise what is the point of discussing??

    Of course VSTOL  is more complicated an has more weight if it didnt have VSTOL capability.
    Finally, I am going to cry of joy.  cheers

    It it more complex, is it heavier then without VSTOL and...  ?   dunno  dunno  dunno
    Weight and complexity affect performance. No more questions Sir

    OK tell me now who kidnapped original LMFS and substituted some reasonable no-VSTOL-h8er?  Suspect  Suspect  Suspect
    The hater is in place don't worry lol1

    Hmm why do you assume always VSTOL has to be "additional" to CTOL?What about to build VSTOL only fighter?
    Care submitting any functioning alternative solution for supersonic flight? I am all ears, really.

    Yak-41 was a flying example. It was designed as VSTOL only.
    JSF F-35 is a joint strike fighter not a fighter. So payload and stealth are top requirements here.
    No I don't mean that. Take the Yak-41. It has a main engine for horizontal flight. And then, ADDITIONALLY to that, two engines in the frontal section of the fuselage to create vertical lift.

    In order to have a STVOL without substantial downsides due to extra weight and space you would need the vertical lift in the front to be used also for horizontal flight. Harrier managed to do it... and it was nevertheless a subsonic, crappy, unreliable plane.

    Without a lift concept that solves this, I am not seeing any reasonable way of claiming the STOVL can be every bit as good as the STOBAR/CATOBAR. But well, above you already admit it will be heavier and more complex so we agree... by some miracle
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    Post  Vladimir79 on Mon Oct 08, 2018 2:53 pm

    LMFS wrote:
    Why? There are many examples of LO or VLO designs with canards.

    From what I have seen, they have leading and trailing edges that need to be treated as those of wings in regards of scattering. Transition to the body needs to be done carefully (see for instance LEVCONS on Su-57 as an example) and FCS needs to take care of their deflections to minimize impacts on RCS. But other than that I don't really get what is the big issue... benefits to aerodynamics are substantial

    There are no VLO examples with canards. The only two are the F-35 and the F-22 and they don't have them. Canards are increased surface area, especially in the most important aspect being frontal. MiG 1.44 wasn't stealthy enough. Now the Chinese have picked up on a flawed design and taken it to the next level of folly. The MKI picked up the J-20 on radar at a couple hundred kms.

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