SOLVED. Y/A book series where the main character is around 16 and can fly a biplane due to his father being a pilot; post-apocalyptic. Spoilers ahead? [s]

[Simon]

The world itself is post-apocalyptic, though I don't remember why, and the main character's mom is a police officer, and his father is away because he's a pilot when the world collapses I wanna say. The main character knows this guy, and I wanna say his name is Herbert, but I don't think that's right, and he knows an awful lot about how people act when the world begins collapsing. About a quarter of the way through the first book, the main character, his mother, and the Herbert guy regroup the neighborhood and they build walls and collect water in swimming pools and have a mini police force. That's all I can really remember, other than the fact that they blasted a bridge apart when some scavengers tried to mobilize on them to kill them, killing them in a ravine thing.

[Angela]

The Rule of Three by Eric Walters?

[Simon]

Yesssssssssss. That's itttt! Thank you!!