In constrained plane environments https://github.com/vk2diy/hackbook-m4-mini works well and has long battery life. I fix the screen to the seat using adapted helping hands and use a wireless keyboard/mouse for input. Super comfy as long as your eyes can deal with the reduced distance (look down the aisle occasionally).
Magnifying style shop glsssed might actually be perfect for this. I use them for electronics repair (they also only focus close which is sort of a benefit here). Downside for me is they fit in a way that is too high (they are designed for looking straight ahead) that would be great for this