No need to 'edit' the tables. As you found out, some can't be edited. But they can be replaced. Open 'to edit' air and place (half screen) on left. Open 'source' air and place (half screen) on right (ie:side by side, with both visible). Both air files must be for same type/engine/power airplane-but you know that already, I guess. Choose wisely.
On left air, right click section (ie: 509) and choose 'Remove Record'. On right air, right click section (ie: 509) and choose 'Copy to Clipboard'. Go back to 'edit' air, right click anywhere, then choose 'Add From Clipboard'. The section will be replaced with new one. Repeat for other sections you want 'changed' by copy/paste with no (Hex) edits necessary. Click 'File' + 'Save'. Done.
Chuck B
Napamule