Apart from the detaching and flying a battery part, you've also got to seamlessly switch power source in midflight
Otherwise you've depleted 25% of all your batteries and jettisoned a single battery pack, which (like the others) is 75% full.
(That might of been a source of confusion).
The difficult part isn't designing a means of switching from one battery pack to another, it's convincing regulators that took decades to be convinced by things like two engines being enough redundancy that a mid-flight power source change is a good idea
Bureaucracy is not the problem being posed here. It was a question of technical possibility.
When I said it's trivial, I meant trivial. You can simply just discharge one pack preferentially over another. It's something that would be inherent to the power management circuit.
Whatever you're imagining, this is not that. There is no giant lever to changeover the packs. The circuit is never broken and power is never interrupted. It really, truly is as simple as drawing power from one battery and not the other.
Given the ridiculous power requirements involved, 'simple' is perhaps a bit generous. But the complexity is in physically handling that amount of current, not in switching it. Again, these are solved problems with standard solutions. This is stuff we've been doing industrially for years.
That seems like the easiest part, flip the relays to disconnect the battery pack, evaluate remaining capacity and if the detachable pack is discharged by the expected amount and the onboard packs are full, then go ahead and jettison.
You have to do that realibly, millions of times without failure, safely and without loosing redundancy. Flipping a relay is easy, doing in flight with one of most safety critical systems not so much.
Man, I just hope all those aerospace companies YC is funding have founders with a much better understanding of these things...
>Flipping a relay is easy, doing in flight with one of most safety critical systems not so much
This system assumes an aircraft that is already battery powered and requires routinely detaching a very heavy piece of equipment in flight without causing undue risk to the aircraft and then autonomously flying that heavy battery pack over populated areas in airspace shared with other aircraft. The power control system for detaching battery pack is the least complicated part of this system.
Otherwise you've depleted 25% of all your batteries and jettisoned a single battery pack, which (like the others) is 75% full. (That might of been a source of confusion).