Then how MiG-25 maintain its stability at low speed ?
MiG-25s don't operate very much at low speed, but don't need fly by wire flight control systems... which didn't exist in the 1950s when it was designed.
Actually I don't think even the MiG-31s have FBW flight control systems...
So what method MiG-25 uses to deal with it ?
Just standard hydraulic booster conventional controls.
MiG-25 aerodynamic design is the standard for 4th gen. The broad hull, made by adding 2 inhale-engine to the side of the cockpit, significantly increases the G-load, and concentrates the G-load into the hull rather than the wing. That enable MiG-25 to sustain much larger G-load, which is vital for 4th gen fighter.
The MiG-25 is the basis of the F-15 and F-14, but part of the requirement for being a 4th gen is some multirole capability. The MiG-25 in its different variations had very different roles (interception, recon, and strike bomber) but was not multirole.
MiG-25 has electronic-controlled air inhale, which enable the air flow to be controlled and changed in different speed, payload, and conditions. Su-27...37, MiG-29, F-14/15 learn from it.
Variable air intakes are necessary for mach 2+ flight speeds. the F-16 has a fixed intake ramp and therefore can't fly faster than mach 2.
In order to deal with the low stability at low speed, MiG-25 approached fly-by-wire, or in my language, "computer pilot". The human pilot became similar to a game player with a joystick, sends electric message to the "computer", and the "computer" does the task of driving the aircraft.
In that time, MiG-23 was created as an intermediate, situational solution. MiG-23 replaced the computer pilot with the swing wing. Although the swing wing gear is heavy and weak, but MiG-23 is cheap and it was a good solution to fill the gap when MiG-25 is still developing.
MiG-23 and MiG-25 are very different aircraft for different roles... and for different customers... MiG-23 is long range interceptor for the Air Force (MiG-21 is short range interceptor for Air Force), MiG-25 is long range high speed interceptor for PVO or air defence forces.
For a long time I don't understand why Vann many times tagged you in his post, and I don't understand why Werewolf dislikes your thinking in politics.
TR-1 calls it realism... though most of the time I think it is pessimism... when you get lied to all the time you end up assuming it is another lie... except if you are American because although you know your government lies to you your government wouldn't lie to you about important stuff... right?
Russia is the biggest threat to the world... above ISIS and Ebola...
that is actually true but incomplete... what they actually mean is that Russia is the biggest threat to take away Americas global power and position... which makes sense because Ebola is something the US created just like ISIS... even if they lose control they are pretty safe from both.
Russia on the other hand is a real threat to US domination...