3 ms·

It's a fairly easy number to check: Freight aircraft don't have windows or window frames. What is the delta on their empty weight compared to a passenger vers

• paul_milovanov 8y ago
  I'll speculate that a freight 747 is still fundamentally structurally a plane designed to have windows (with the correspondingly reinforced fuselage) but with minor tweaks. I'd be very surprised if that's not the case. You'd need a plane that's designed from the ground up to not have windows in any configuration.
  • rbanffy 8y ago
    Still, if the difference is that brutal, there would be a huge niche for planes that have no passenger version and are designed to never have windows.
• macoovacany 8y ago
  Not as much as you'd expect. It's easier and cheaper to get a design with windows (and their supporting structure), and not cut out the holes for the windows in the skin. The resulting structure is going to be only marginally lighter, but also much more fatigue resistant. The savings would show up in the changed inspection intervals.