The shape of warfare is changing and the Cold War missions that the legacy types were ace at aren't really relevant from both a risk-taking or financial-burden (keeping everyone current) level. C-130 can do things that is arguably not that relevant any more but we keep these skills just in case. The kicker is that by retiring the C-130 before the A400M is ready you're leaving yourself with a capability gap that will take a long time to back-filll, even with things that the A400M aircraft is technically cleared to do right now, but nobody aside from the test pilots and maybe some of the instructors have ever done. This isn't high-tech merit stuff either, these are basic air drop and air-land skills.
Without having a crystal ball or a direct line to the CAS, we must make some assumptions:
- A400M probably isn't going to be flying OLF alone and unafraid or even multi-ship to drop supplies below the radar to a Long-Range Recon Patrol.
- It probably won't need to low fly much at all since the on-board kit will allow it to do almost everything IMC. Our (and allied) 5th gen air force will negate the IADS and enemy DCA and thus will allow it to transit medium level to the DZ / TLZ and do a steep approach to avoid the small arms to drop / land.
- It will need to do 16X stuff - Low Level Para, CDS / Light Stores, day and night natural surface TLZ operations, and maybe some heavy drop of vehicles.
Op FORTIS . (This, in the author's opinion, is where it should be at minimum before retiring C-130)
- It will need to do some specialist stuff. Probably high-altitude parachuting, probably dispatching small and large boats plus troops in the littoral, high seas, and inland areas.
How many of these things can it currently do operationally (none?) and how many will it be able to do by 1st April 2023? (hopefully some!) How many of these capabilities will we decide we don't need anymore having been without them for a while? How many are we going to struggle to stand back up again credibly when all the people who've been doing it for decades have moved on? It's clear that A400M is the future, it's just that the future may have arrived too soon.
If we're playing the three types off each other, then as other people have said the A400M is the middle aircraft. Bin off C-130 and have a bigger, softer Tac Airlifter (and ask Uncle Sam for help with complicated stuff the odd time that comes around) or bin off C-17 and have a smaller, slower Strat Airlifter (and hire an Antonov for moving really big stuff the odd time that comes around). Obviously in Mobility utopia we'd bin off A400M, buy more C-17s from the re-activated factory, and have MC-130Js like the Americans. Jagger said something about getting what you want.