At supersonic speeds the center of lift moves backwards, that means, the nose tends to fall.
That is correct.
To compensate for that your nozzles need to point upwards, that is, create a downward force, to lift the nose.
That is not correct.
They don't actually point upwards they might shift angle a few degrees which will compensate for the shift in cg, but they will maintain the angle of the aircraft into the incoming airflow to maintain attitude without having to shift a horizontal tail surface or canard foreplane to do the same... a few degrees shift in engine nozzle will not create drag or increase RCS... a shift in canard or tail surface will.
That force needs to be compensated with more lift to keep level flight.
There is no change in lift, just a shift in cg that is compensated by a slight change in thrust line.
Think of the V-22 or the Harrier... but instead of using vectored thrust to take off vertically you just use it like a normal aircraft only moving thrust angle by 10 degrees up or down at most to change the angle of attack of the aircraft to optimise the efficiency of the wings... so you can remove the horizontal tail because you are using the engine for up and down force.
It would optimise drag even better because the tail surface would essentially have zero drag and RCS which wont increase in turns or at different flight speeds.
The one thing in common with all drawings of supposed 6 gen fighters is a main wing and no vertical or horizontal tail or canards... less weight, less drag, less RCS.
Yet with TVC you get all the turn authority any physical surface could provide at any flight speed including zero where normal control surfaces are dead weight.
A downwards force needs to be compensated, not differently to tail deflection.
But a downward force from a control surface is not the same as a downward force from an engine nozzle... you are trying to say that if there is enough downward force from a tail surface that the plane will fall out of the sky because the downward force will exceed the lift of the wing and the total downforce will make the plane lose lift and crash, but that is bullshit... if the downward force from the tail or the upward force from a canard at the front is too much that does not directly cause the plane to go up or down... it does what it is supposed to do and causes the aircraft to rotate around its cg to compensate for the shift in cg.
The F-14 has small surfaces in the wing leading edge that deploy in some flight modes to prevent cg going to dangerous places at low speed where conventional controls might not have enough effect to compensate... it does not have thrust vectoring engines obviously.
The downwards or upwards force of the engine doesn't make the aircraft descend... what it does is as you say... stops the nose from pitching down ... that is all.
It doesn't make the aircraft fly faster or higher or lower... and it does so without increasing drag like moving a canard or horizontal tail surface would... like I am saying.
It is better to have lift in front of the CoG than downforce behind it.
Surely it makes no difference at all where the lift is as long as it is kept near the cg, which is what deflecting canard or tail or engine nozzle does... the latter does so without increasing drag.
Yes I know. The point you seem to be missing is that pitching the nose down is done by creating additional lift with the TVC while pitching it up demands the nozzles to press the tail down.
And what you seem to be missing is that travelling through that transonic area of flight speed causes the cg of the aircraft to move and the shifting of TVC angle doesn't increase AOA... it maintains it while the cg is moving and then stabilising... once past the transonic speed the cg settles down and does not move at any other flight speed so temporarily shifting engine nozzle trim to compensate maintains AOA it does not change it.
Using canards or tail surfaces also maintains AOA but generates drag and effects RCS with it moving to compensate and then moving back as you accelerate further through to higher speeds.
So one way it creates lift, the other reduces it.
No. They both essentially do the same thing they are turning the aircraft around its cg to maintain AOA... it is the lift from the main wing and the fuselage lift that keeps the aircraft in the air most of the time the canard or tail are neutral... when they are not their job is still not to keep the aircraft in the air... their job is to control the AOA of the aircraft... which can increase or decrease drag and lift.... Canards and or tail surfaces maintaining an AOA of 120 degrees without TVC engines not only does not create lift but will lead to a super stall on most conventional aircraft almost immediately.
That was the whole rationale behind canards on longitudinally stable planes BTW, so instead of a tail reducing lift all the time to avoid nose falling, you have a foreplane increasing it.
The only real advantage of the canard arrangement is making the aircraft stall proof where the canard stalls before the main wing and forces the nose to drop before the main wing stalls and control of the aircraft is lost.
Interestingly the An-2 has similar properties... if your engine fails you just pull back hard on the stick and hold it there... the aircraft will slow down until the flaps and slats deploy and the plane slowly sinks to the ground...
This seems legit, dont know if it was posted before, just seen it on another forum.
The missiles are not right, but the obvious question is why would it be landing or taking off with missile bays open... except as a nice photo op... in which case I would expect a much better quality photo...
Interesting though...
Compared to deals like France/India, I think Russia gave Algeria as good of a deal as they could.
They would need to give Algeria the coatings needed to maintain stealth, and the technology associated to apply and maintain them on the aircraft, plus likely simulators and of course new weapons to go with them too...
Perhaps 20-40 million dollars worth of stuff for a 100 million dollar aircraft... the Rafale was 222 million but it was new.... they had never operated that aircraft before so that would include a pool of spare parts and training and support equipment and machinery to get them working and keep them going till their next purchase... would be the same for the Su-57.
Wonder if this will lead to renewed interest from India... or even Turkey.
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