Oh my word - they COULD be made to open! My jaw hit the floor upon seeing this fresh blog post below, which describes a retrofit for the T1N Sprinter. I had always assumed, perhaps incorrectly, that even if there is a modified open-able window available somewhere in the aftermarket, installing it would probably be too disruptive to the Airstream finishes and therefore not very feasible. After seeing that post, I'm not so sure.
All this time, I've been struggling to create one or more screens to use when the back door(s) are left fully open (e.g., #43 in this thread
). But one of the main reasons why I/we sometimes have to leave the back door(s) fully open is that there is no way to open their windows to achieve the desired back-to-front ventilation effect (in the southern summer, that "desired" ventilation becomes "required" ventilation). We might could get to the point of diminishing returns just by installing open-able windows, and it would offer better security in certain stealth camping situations in which leaving the back doors open or ajar is a questionable decision.
Why doesn't Air Forums offer a bangs-head-on-desk smilie? Because I would definitely be a repeat user of that. The closest available smilie seems to be this one, interpreted as self-inflicted.
Anyway, I plan to look further into the feasibility of this option as future time allows. And I don't find an existing thread devoted to back door window discussions, so I thought I would plant this one now.
Here's the post.
SLIDING WINDOWS FOR THE REAR DOORS