Optimal 5th:4th gen ratio?

Have not recalled seeing this discussed elswheres, and the Tactics subforum seemed as appropos as any, so I'ze done plunked it here.

The recent thread mentioning Bulgaria's plans for an upcoming tactical fighter aircraft tender caused me to ponder the following question:

For nations that cannot afford to buy all 5th gen aircraft, what is the optimum 5th gen to 4th gen ratio? That is, where is the elbow in the effectiveness curve vs cost as one considered different ratios of 5th gen to 4th gen aircraft.

Is it 1:2? 1:4? 1:10?

As Red Flags continue apace with F-35's and F-22's mixed in with F-16's, F/A-18's (including Super Dupers and Growlers), F-15's, Rafales, and Typhoons, the answer is probably still being discovered as CONOPS are developed, tested, and refined. So perhaps this question has yet to be answered by those who would not tell anyway.

In the case of Bulgaria, they do not appear to have the money to buy one squadron of F-35's, let alone F-35's plus a bunch of 4th gens.

But perhaps a nation such as Poland might opt for a squadron or two of Lightnings plus an appropriate number of Vipers.

My guess is that a ratio of about 1:4 of Lightnings to whatever 4th gen grabs your fancy would be optimal. That being said, since the price of the Lightning will soon be less, if it is not already, than any new production 4th gen (possibly excepting the Super Duper?), then the question may be how many used 4th gens does one acquire to optimally enhance F-35's? Used Vipers, potentially upgadeable to the -V standard, might be the way to go there.

I would say 100% 5th gen and 0% 4th gen or resuming buy all 5th gen aircraft even because the cost of modern 4th gen (the so called 4.5th gen) is very similar, almost the same and even in some/many cases more expensive than 5th gen and this not to mention effectiveness.

And even assuming you could buy 4th for a rather cheap price (which you basically can't except perhaps for some 2nd hand F-16's and then upgrade then to F-16V) it would be better to have:
1- a sole fleet of 60 5th gen fighter aircraft
then,
2- a fleet of 35 5th gen fighter aircraft and 70 gen fighter aircraft (if you want to use a 1:2 ratio) or a total of 100 planes.

Option 1- is not only cheaper at all levels which ensures better readiness and with this a much more effective and more survivable fighter fleet than option 2-

What is the mission?

Not all missions require a 5th gen A/C.
And F-16's run at half the operational cost of F-35.

It depends on your metric of optimality.

F-16's run at half the operational cost of F-35.

Per the latest SAR the F-35 runs only 14% more than the F-16, not DOUBLE.

Do try and keep up.

If someone can't afford enough F-35s, they certainly can't afford to buy two new types of planes.
4 gen is in the mix only if there's already bought frames with enough flight hours left to warrant keeping them flying. As in sunk cost. Building new infrastructure from the ground up for a new 4 gen and 5 gen would be ludicrous.

There's a Canadian study about this.

Summary of Bridging and Mixed Fleet Analysis Findings

The analysis found that a mixed fleet of higher capability aircraft able to fulfil the most challenging NATO missions and lower capability aircraft able to fulfil Canada's NORAD obligations totalling more than 65 aircraft could not provide the same overall capability as the single fleet of 65 higher capability aircraft. Moreover, there was strong evidence that unless the purchase cost of the fleet of lower-capability aircraft was half the purchase cost of the fleet of higher-capability aircraft, a mixed fleet would provide less capability at a higher cost.

https://www.tpsgc-pwgsc.gc.ca/app-acq/a ... f-eng.html

This probably means that the only new mixed fleet that makes sense for smaller air forces is one that combines a jet trainer and a fighter. Like T-50 or FA-50 and F-35.

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

I am keeping up.
https://www.flightglobal.com/news/artic ... fl-421499/

Looks like CPFH for a F-35 is slightly HIGHER then double the F-16 cost.

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

Yes, USN is buying more Super Hornets. Yet, that will very shortly come to the end. As production of the F-35C will increase to at least 24 Aircraft per year post 2021. As for Israel wanting F-15's instead of F-35's that is wild speculation and has no basis in fact......

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

Yes, USN is buying more Super Hornets. Yet, that will very shortly come to the end. As production of the F-35C will increase to at least 24 Aircraft per year post 2021. As for Israel wanting F-15's instead of F-35's that is wild speculation and has no basis in fact......

if you have full control of the air situation as Israel does, stealth becomes less and less important.
Anf their F-15's have a solid reputation.

I am keeping up.
https://www.flightglobal.com/news/artic ... fl-421499/

Looks like CPFH for a F-35 is slightly HIGHER then double the F-16 cost.

Now try OFFICIAL, "APPLES to APPLES" SAR information.



Do try and keep up.

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

Israel is not in favor of more F-15s instead of F-35s. They're wanting both.

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

Israel is not in favor of more F-15s instead of F-35s. They're wanting both.

Israel may want to acquire some more second hand examples of the F-15. Yet, I doubt she would use a large portion of her Defense Budget. To buy more F-15's when she could have additional F-35's! (just saying)

The USN is buying more SHs and the Israelis are reported to favor new F-15s in lieu of more F-35s so it would appear CONOPS will largely determine the ideal ratio which would be unique to every air arm.

Yes, USN is buying more Super Hornets. Yet, that will very shortly come to the end. As production of the F-35C will increase to at least 24 Aircraft per year post 2021. As for Israel wanting F-15's instead of F-35's that is wild speculation and has no basis in fact......

if you have full control of the air situation as Israel does, stealth becomes less and less important.
Anf their F-15's have a solid reputation.

Sorry, Israel is in love with the F-35 and has made no formal (i.e. official) request for F-15's....

And regarding the F-16 vs F-35 operating costs lets not forget that:
1- The F-35 still didn't enter full production rate.
2- The F-16 benefits from DECADES of service which means that its maintenance is more than optimised. Give the F-35 a few more years and you'll see its operating costs going down (as its maintenance gets more optimised). So it's likely possible that the F-35 operating costs will eventually become lower than the F-16 or any other 4th gen fighter aircraft for that matter.