Hi Kathy,
Have you tried contacting the National Archives?  We have gotten some aerial indexes from early 1950s from them but we had a former student, who was there on his own, scan them for us. It was complicated but we did get what we need. You can hire a researcher donut for you. The National Archives were responsive to my emails when asking about their collections.

Heather Ross
Map Specialist
Penn State University Libraries

________________________________
From: Maps-L: Map Librarians, etc. <[log in to unmask]> on behalf of Kathy Stroud <[log in to unmask]>
Sent: Friday, July 26, 2019 7:07:26 PM
To: [log in to unmask] <[log in to unmask]>
Subject: Looking for air photo indexes 1938 AAS (Klickitat Co, WA) and 1949 AAE (Sherman Co., OR)

All,

I’m looking for aerial photograph indexes for two older USDA flights:

938 AAS (Klickitat Co, WA) and
1949 AAE (Sherman Co., OR)

We have frames, but not indexes.  If you can get us a copy of the indexes,  I’ll be eternally grateful.

Thanks for checking.

Kathy Stroud
David and Nancy Petrone Map/GIS Librarian Knight Library
1299 University of Oregon
Eugene, OR 97403-1299
541-346-3051

“A map is not just a picture—it’s also the data behind the map, the methodology used to collect and parse that data, the people doing that work, the choices made in terms of visualization and the software used to make them.”