Like i believe i touched in the past, imo it will be foolish and reckless to retire the F-14 fleet even if the Su-35 arrives. On the contrary, this, as the pressure on the F-14 fleet will be reduced, should be an opportunity to upgrade them at whichever highest standard Iran is capable of, with either iranian or russian radar, AL-31F engines, not to mention Fakkour, Maghsoud, Azaraksh, Arash AAMs etc.
A depot level upgradation of F-14A to F-14 AM costs around 5 million USD, its a novel air-superiority jet with extreme capabilities. With your mentioned upgrades the cost will increase upto 25-30 million USD per airframe. Why waste such money on an old airframe when same amount of money can provide Iran with MLUed or new MIG-29M/35 or 2 x such upgrades = 1 x SU-35S itself.
- At best what IRIAF can do is to use Russian or Chinese companies for bringing airframes to as minimum hour condition as possible. Iran lacks some of the industrial capacity which this task will require.
- F-14AM program included mid-level upgradation of AWG-9 to APG-71-like performance with complete digitalisation, mechanical parts removal, and change in cooling system. They can probably install an AESA antenna on this radar along with ECM control which it inherently lacks. Such a move will enable the radar to search even a small fighter above 200+ KM and track it at LR-BVR ranges while itself being un-jammable due to AESA antenna.
- Two way datalinking with IADS, SU-35S, Qaher/Karrar wingmen.
- Similarly, a local IRST can be installed on this large airframe, Iranian domestic IR/IIRSTs are vastly modern and are used in air-defense. See the Khordad examples. That will allow the jet to tackle even stealth fighters or work silently by switching its own radar off. HMD slaved WVR-HOBS Azaraksh and Fakour-90/Maghsoud on entire fleet means its even a meaner interceptor than it currently is.
- More importantly it should have Fattah Hypersonic ALBM version launch capability just like Russians use their MIG-31BM fleet.
Even if such an upgrade costs around 12-15 million USD, the resultant plane will be a bigger threat in sky than MIG-31BM currently is. Its operational cost is high but with SU-35S inclusion, they dont have to fly CAP with these F-14 airframes, they can just keep few airframes on border QRA duties while rest of the fleet is stationed underground.
Only if large numbers (at least in the high tens) of Su-35 and Su-30SM are delivered in a relatively short period of time (say before 2030) would justify retiring the F-14 fleet. But if only the rumoured 25 Su-35s are delivered, that is not a sufficient number to warrant retiring the F-14 imo. On the contrary, say 3 dozens of upgraded F-14s will quite nicely complement these 25 Su-35s. Even if 50 Su-35 are delivered, i would still keep the upgraded F-14s around, that would make 80-90 long range modern heavy fighters guarding iranian airspace in the near to medium term.
The 50 airframe news came from 3 x reliable and independent journalistic sources. Seems realistic too. To me even 50 is a small number. IRIAF needs atleast 100 x SU-35S/30SM for now along with complete MLU-upgradation of MIG-29 fleet with few new airframes.
If the opportunity arises in the 2030s, only then replacing the F-14 with a modern 5th gen heavy fighter (basically Su-57, though chinese J-20 is another option and who knows, the 6th gen J-50 might be a wildcard) should be done.
But this is the absolute best case scenario for IRIAF.
China wont give jack to Iran. Russia will, as long as Ukraine theatre is hot and Russia needs Iran as a large ally, weapons supplier, acces to Persian Gulf (INSTC) etc. After Ukraine war is over, Russia will naturally want to re-establish its relations with US+EU using its relation with now "pseudo-nuclear armed" Iran as a price to pay, so the window of opportunity for Iran is small here. If no TOT or local assembly line is established for Flankers inside Iran I can totally see Russia pulling another Rafsanjani-MIG-29/31 and S-300 like backout on Iran even if the fleet price is paid before deliveries.
I am rather more concerned about the seriousness of Iranian leadership in rebuilding IRIAF. These people pulled the plug on IRIAF by devastating budget cuts in the past. Fighters are crashing, FMC airframes are getting fewer in numbers. Hard to believe this gang will pay billions of USD for a force they abhor.