Flight Highschool - Ch. 26

[MangaDex]

 

[VooXoo]

The downgraded thing is a reference to when a country sells their miltary hardware or software to another nation, they don't want to share what they achieved with yeard of R&D so sell a nerfed version, is of course able to work perfectly fine and the buyer knows how the lower performance, but for some countries that is the only way to be up to date with their weaponry, not having a system that develops weapons and it would take decades for it to catch up.
Even "only" crafting the metal alloy that can resist freezing at high altitudes or the high temperature of the reactor of planes takes many years, great minds and a immense budget.