Hi Leendert,
Thanks for that. Frankly I had no idea. Could you please provide a little information on the purpose of the Air Base Squadron Technical Schools ? I take it that they were used for work on instructional airframes from the text that goes with the link below.
Also I attach a link to the YP-37 as mentioned in a previous post:
https://usaac-official.tumblr.com/po...n-in-use-as-an
Regards,
Clint