Current USAF plan is to keep 187 F-22s, 254 F-15 C and 221 F-15E in service, replacing 716 A-10s and 2 154 F-16s with 1 763 F-35As.
Problem with that is multifold; first, large unit and maintenance costs. Per-unit cost of 304 million USD per aircraft, 197 million USD flyaway, and operating cost that will likely be around 48 800 USD per hour of flight,1 763 F-35s will cost 535,952 billion USD to procure. Operating costs for that fleet will be 86 034 400 USD per hour of flight.
187 F-22s in service have so far cost 79,475 billion USD to procure and upgrade (including fixes) and have total operating cost of 11 407 000 USD per hour – 61 000 USD per hour per aircraft. This means that combined F-22/F-35 fleet will cost 97 441 400 USD per hour of flight.
To compare with these costs, “ancient” F-16C that are now being replaced by F-35 have operating cost of 7 000 USD per hour of flight. F-15C costs 30 000 USD per hour of flight, F-15E costs 28 000 USD per hour of flight, A-10 costs 3 000 USD per hour of flight. Eurocanards cost 18 000 USD per hour of flight for Typhoon, 16 500 USD per hour of flight for Rafale and 4 700 USD per hour of flight for Gripen.
Maintenance downtime is 6,2 hours per hour of flight for A-10, 19 hours per hour of flight for F-16, 10 hours per hour of flight for Gripen, 9 hours of maintenance for Typhoon, 8 hours of maintenance per hour of flight for Rafale, 20 hours per hour of flight for F-15, 45 hours per hour of flight for F-22. (I wasn’t able to confirm Eurocanards’ maintenance downtime figures, however).
Thus, by using maintenance and flyaway costs, and ignoring R&D costs that have been sunk, we can break down costs of desired USAF fleet as:
187 F-22A: 46 750 000 000 USD price, 11 407 000 USD per hour of flight
254 F-15C: 10 820 400 000 USD price, 7 620 000 USD per hour of flight
221 F-15E: 9 757 592 000 USD price, 6 188 000 USD per hour of flight
1 763 F-35A: 347 311 000 000 USD price, 86 034 400 USD per hour of flight
For total of 414 638 992 000 USD, and costing 111 249 400 USD per hour of flight.
By using Desert Storm and current sortie rates (1 sortie / day for F-15, 1,2 for F-16, 0,3 for F-22, 1,4 for A-10), we see that F-22s will be able to fly 60 combat sorties per day, and F-15Es will be able to fly 221 combat sortie per day. F-15Cs will be able to fly 254 sorties per day. While I don’t know F-35’s maintenance downtime, it can be estimated that it will be able to fly 500 – 800 sorties per day. Thus above force will be able to sustain 2650 sorties per day.
Two fighters, F-22 and F-15C together cost 57 570 400 000 USD, and 19 027 000 USD per hour of flight. Strike-oriented F-15E and F-35A will together cost 357 068 592 000 USD and 92 222 400 USD per hour of flight.
Replacing F-22 and F-15C with F-15As gives 1 351 aircraft, costing 40 530 000 USD per hour of flight, and able to support around 1 400 sorties per day. Replacing F-15E and F-35A with F-16C gives 5 951 aircraft, costing 41 657 000 USD per hour of flight, and capable of supporting around 7 140 sorties per day. Better option would be 5 000 F-16C and 3 800 A-10, costing 357 billion USD to procure and 34 900 000 USD to maintain per hour of flight. 5 000 F-16C can support 6 000 sorties per day, and 3 800 A-10 can support 5 320 sorties per day.
Replacing F-22 and F-15C with Eurofighter Typhoon gives 480 aircraft, costing 8 640 000 USD per hour of flight, and able to support 1 152 sorties per day. Replacing F-15E and F-35A with Saab Gripen gives 5 951 aircraft, costing 27 969 700 USD per hour of flight, and able to support 13 092 sorties per day.
To sum up:
F-22A + F-15C + F-15E + F-35A = 2 425 aircraft and 2 650 sorties per day. Total procurement cost 415 billion USD, total maintenance cost per hour of flight 111 million USD.
F-15A + F-16C = 7 302 aircraft and 8 540 sorties per day. Total procurement cost 415 billion USD, total maintenance cost per hour of flight 82 million USD.
F-15A + F-16C + A-10: 9 851 aircraft and 12 720 sorties per day (7 400 sorties by air superiority-capable aircraft). Total procurement cost 415 billion USD, total maintenance cost per hour of flight 75 430 000 USD.
EF2000 + JAS-39C = 6 431 aircraft and 14 244 sorties per day. Total procurement cost 415 billion USD, total maintenance cost per hour of flight 37 million USD.
Thus either F-15A + F-16C or EF-2000 + JAS-39C option would be superior to an all-stealth option USAF is promoting in both cost and cost effectiveness area. Not only is large number of sorties per day required for establishing air superiority, it is also required for pilot training, which is one of most important things any air force must do; simulators are just that: simulators, and while they can simulate live training, they cannot replace it.
Meanwhile, stealth is overrated: during Kosovo War, stealth F-117s suffered greater number of casualties (1 aircraft shot down, 1 damaged and mission-killed but returned to base, never to fly again) than non-stealth F-16s (1 F-16 shot down), despite being “stealth”, and despite flying lower number of sorties – 1 300 sorties compared to 4 500 sorties for F-16. Final nail on the “stealth is required to cope with SAM’s” coffin is SAM effectiveness rate through war: 0,36 %. Even air-to-air BVR missiles have Pk in single-digit percentages against capable opponent – after lock-on is achieved, and assuming anyone even turns radar on. IRST + RWR – equipped aircraft can stay completely passive, leveling the playing field by forcing stealth aircraft to rely on IR sensors – where smaller, non-VLO aircraft will have advantage – or to radiate and give up its position; and air-to-air anti-radiation missiles, or BVR IR missiles coupled with cueing by aircraft’s defensive suite, can force everyone to rely on passive sensors only.