Let's talk about the hangar...
It is not shown yet in the video and screenshots because it is under construction, but you can see a quick preview here:
Things to do at the hangar:
1. You can choose the altitude for the next run. There are different bonus / malus based on it.
2. Spend gained warbonds to repair / refill your plane.
3. Check out your skills / upgrades.
https://store.steampowered.com/app/2622300/Until_the_Last_Plane_1942/