Idea: Adapter for Loose Outlets

The Background

I've been doing a lot of flying lately. And there's one problem that's absolutely infuriating to me.

The outlets are way too loose.

Have you had to deal with this? You finally find the one seat in the airport next to an outlet.

You sit down, relieved, and pull out your phone charger. You plug it in. It falls right out.

You end up jerry-rigging a stand using your backpack or suitcase to try and hold it in while you charge. It doesn't work.

The Idea

The idea is an adapter that fixes this problem. I'm not an electrical engineer, but I feel like it should be fairly easy. Maybe there needs to be a little piece at the end that, once it's in, you can flip down to make the connection more snug.

Or maybe there's some kind of cantilever against the wall to make sure it doesn't fall out. I'm not sure what the actual solution is.

But I want something that will work with any outlet, regardless of how loose it is.