Why Mig-25 was not constructed using Titanium (like SR-71). Was it because of some technological limitation of that time or some other factor

Of course, not.
Russians are well advanced in titanium metalurgy. Look at their titanium submarines.

True reason is number of fighters required.

Russia needed more than 1200 Migs-25 becuse of its enormous frontiers.
That rendered titanium aircraft unacceptable. Even all western countries together could not have afforded it.
Nickel steel did the job well. Titanium is used only in most sensitive areas.

I read about that. Fighters manuver best at their corner velocity. The F-14 had a very low corner velocity, much lower than the MiG-23. The F-14 really didn’t need to pull high g at Mach 2, so I can see why that ability was not worth the expense. The MiG-23 fights best at higher speeds, perhaps slashing with the wings fully swept. The excessive stabilty would be a bigger problem for the MiG-23 than the F-14, which fights very well at low wing sweep. If I was an F-14 pilot who had to go up against a jet with a really low wing loading, like a MiG-17, I’d put the wings back and slash at it. I’d want my glove vanes back then. The military often cuts some feature off a weapon just to save money. The glove vanes made the F-14 a better fighter when it had them, even if it usually didn’t need them.

One of the best american pilots ever, John Boyd instructor in Nellis Fighter Weapons School, said:
“F-14 is underpowered and have poor performance in combat. Pilots call it TOP TURKEY.”
Anybody should have this in mind.

F-14 was overrated in earlier literature. It is poor fighter, except for shooting from the distance.

Glove vanes.
The new F-14D were built without. Ted Carlson gave not all the reasons for that. 😉

In practice, weight penalty of glove vanes mechanism overcame its benefits as lift area. So it’s mechanism was finally put out.

“Ben Lambeth, of the US think tank Rand Corporation, flew the MiG-23UB…
His first impression was the poor view from the cockpit – he was in the front seat. Angle of attack was red-lined at 18deg, and departure and pro-spin tendencies were vicious. Corner velocity… was about 430kt, rather on the high side. Roll response was slow, stick forces were heavy, and Lambeth assesed the turning capability as something between the F-104 and the F-105. In fact, very poor. The “feel” of the Flogger was somewhere between the Tornado and the unslatted Phantom. To summarize, it was no real match even for the Phantom, while against the next generation of Western fighters it was a non-starter.”
“To go up against Western fighters such as the F-14… would have been a nightmare.”
MiG-23, Modern Warplanes, Edited by Mike Spick

“Today, the F-14’s fighter-verses-fighter capability is less respectable. Against older aircraft like the F-4 (or the MiG-23 ‘Flogger’) the Tomcat has few problems…”
World Airpower Journal Volume 7 Autumn/Winter 1991

I would add that one problem that the MiG-23 likely has is excessive stability with its wings swept. As the wings of a variable geometry aircraft sweep back, the center of lift moves back. The tailerons must deflect down to keep the nose up. The farther back the wings go, the harder it is to pull up the nose. The F-111 could only pull 2-3 g at high Mach. Grumman solved this problem by adding the glove vanes ahead of the wings on the F-14. They add lift ahead of the center of gravity when the wings are aft, and allow the F-14 to pull 7.5 g at Mach 2. The MiG has no glove vane. Also, the wings on the F-14 automatically sweep to the optimum angle as its speed changes. The MiG pilot sets his wings at 45 deg for manouver, and they stay there. The MiG-23 really lacks the combat advantage of a truly variable geometry fighter. The body of the F-14 generates about 40% of the plane’s lift, and can keep the plane in the air when the wings are completely stalled. The advantage of this body shape was deemed to be worth copying when the MiG-29 and Su-27 were designed. It goes without saying that the F-14 has a vastly better radar, the advantage of a second pair of eyes seated behind the pilot, and it can absorb more battle damage. Even without Phoenix, the Tomcat has longer ranged missiles with larger warheads than the MiG-23 has. True, the F-14 is underpowered, but the aerodynamics are first rate, and it still has speed and range that few fighters match. The MiG-23 is fast too, and the thrust/weight is a little bit better, but I’ll take the F-14 over the MiG-23 any day. 😎

The report of Ben Lambeth is obviously only for morale boosting. It is not true in many areas.
Angle of attack limit can not be 18 degrees. Mig-23 has good aerodynamics for high alpa flight. Departure prone, vicious pro spin tendencies. All uncorrect.
Look at russian advertisement for flights in Mig-23 for civilians.
They say it is very maneuverable and safe even for civilians with no flight experience. Can we say the same for F-4 or F-104 !!!! Of course, not.

In Lambeth report there is no mention of Mig-23 great climb, acceleration and sustained turn. In all that F-14A is poor.

About wing glove vanes, you should know that in F-14 these are put in fixed position in 90’s because it was concluded that they are unneccessary.
One more myth about F-14 eliminated.

You may be an engineer, and I respect that, but I politely submit that you are mistaken if you are claiming that the MiG-25 could achieve Mach 3 with external stores. This is simply not the case.

Russians have always been great metallurgists, and the Foxbat and Foxhound are indeed immensely strong airframes with respect to thermal stress. The limiting factor was the engines, which simply weren’t technologically on par with those of the Blackbird.

It is true that Mig-25 can not achieve Mach 3 with external stores.
With 4 big missiles or 4 X 500 kg bombs, it is limited to 3000 km/h. That is 2,83 Mach.
With such load it is limited by stability, not engines.

By the way, J-58 engines of SR-71 is not so technologicaly advanced. Secret behind SR-71 speed is propulsion system, not engines.

Mig-25 engines are more advanced than is usualy thought. Its R-15 engines have transonic compressor with no equivalent in the west.

R. A. Belyakov gives 648 kt or Mach 0.98 for MiG-25P and R. p 394 and p 401
The limit are the R-15 engines.
Why did the Russians forgot to add the MiG-25P role to the MiG-25RB role.
Please explain.

The book “MIG” Belyakov, Mig chief engineer: ” Mig-25 have 1300 km/h sea level max speed (IAS).” -page 391

“2,83 Mach with full bomb load” -page 398

“More than 3 Mach without problems, 2,83 Mach is in fact somewhat theoretical. Airplane can exceed 3 Mach without causing damage to engines or sending it to overhaul.”- page 406

Earlier statements are pure propaganda.

As for roles, aircraft as such is capable of all these roles and that makes it far useful than ,say, SR-71.

Step away from the bong, comrade.

The Foxbat, while it could approach the Blackbird’s speed, was and is not anywhere close to the same league as the SR-71 technologically or structurally (with respect to intelligence of design, not just brute strength). Even today, 15 years after its retirement, and nearly 50 years since its conception, Russian techies would wet their pants if they got hold of one to play with.

I am aeronautical engineer and I know something about that matter.

Can you be more speciffic in your statement. Do you know that americans couldn’t made radar dome, in YF-12, that could withstand extreme temperatures at 3 Mach. Even Hustler B-58 had a serious problems with radar cooling at 2 Mach. End imagine 3 Mach.

Russians succedded to built radome which could not melt at 3 Mach and also solved radar cooling. Not to speak of missile electronics also subjected at that temperatures.

Mig-25/31 familly are the only combat aircraft which could break through the thermal barrier. And that is remarkable achievement.
All other Mach 3 aircraft are just experimental or non combat flying fuel tanks like SR-71.

And I am not comrade. Comrade will not say that F-4 was the best multi role aircraft ever built and I say that.

Those timelines aren’t right at all.
Israel may have “thought it was going to be crushed” during the first days of Yom Kippur War –Maybe. But certainly not by the 13th of October.

For those who would have lost track of the dates, that war started on 06-Oct-1973. It was indeed very tought during the first 3 days on the Nortern front, before the reserves arrived to the battle lines. But by the 11th, the Syrian army had been defeated and thoroughly repulsed — to beyond the pre-war positions.

On the other side, Egypt wasn’t yet defeated by the 13th (it took another 2-3 days until the breakthrough to the canal and crossing at Deversoir), but there was never any risk that Israel “was going to be crushed” there

Henry Kisinger memoirs: ” Operation NICKEL GRASS, Yom Kippur war, airlift that saved Israel.”

It is no secret that Israel has been defeated in 1973 war. Only american airlift saved it.
USAF pilots and F-4’s had to join the battle.
Arabs were stopped by american new weapons: Maverick and TOW missiles and massive help in other weapons and ammo.

These are american statements.