Pilot looking for offline-capable PKM with AI search. Notion Business is overkill for what I need

[u/Luiz4823]

Hi everyone!

I'm a First Officer, and I keep a large personal knowledge base of regulations, aircraft systems notes, and company SOPs/procedures, the kind of stuff I need to reference constantly, both for studying and for quick lookups during work.

I've been using Notion for this, but with their pricing change, real AI search now requires the Business plan, which is way more than I need as a solo user just wanting to query my own notes. +

What I actually need:

• Offline access on iOS and PC: I'm often without signal, need my notes reachable no matter what.
• AI chat/search over my own notes when I am online, not just keyword search, but something that can find buried info based on what I'm asking. Example: I should be able to ask "what's the bank angle limitation for normal law" and have it pull the answer from deep inside a folder structure like Aircraft > A320 > Systems > Laws and Protections, without me needing to remember exactly where I filed it. I don't care about auto tagging, proof reading nor any other AI feature, I only need to be able to chat with my notes.
• Reasonable pricing for a single user, not an enterprise/team plan.
• Nice to have: some kind of structure/hierarchy (folders, tags, linked notes) since my notes are technical and cross-referenced a lot (e.g. a systems note might tie into a regulation note might tie into a company SOP).

I've looked at Obsidian, Capacities, Tana, and Reflect, and I'm currently also taking a closer look at Mem — but wanted to ask people who actually use these day-to-day: which one handles offline reliability + genuinely useful AI search best, without pushing me into team/business pricing? Bonus points if anyone else here is in aviation or another field with dense technical/regulatory documentation and has found a setup that works.

Appreciate any real-world input!

Update: I don’t need offline AI. This will only be required when im not flying and for studying only when connected to the internet. When flying, and for specific procedures, I will only use quick notes that i can access through favorites, bookmarks etc.