Hallo gents!
Thought it will have some of use.
It includes a "in use" airfields as at 27.03.1941 and are for this time only in various stages of construction:
- Permanent airfields 1 st and 2 nd groups of military districts
- Operational and civilian airfields, and transferred to the permanent military district
- Landing grounds Air Force District 1 st and 2 nd groups
- Airfields 1 st and 2 nd groups of the Civil Air Fleet of the People's Commissariat of Health and agricultural aviation, the Air Force transferred the district.
Each of these airports or landing site was appropriated by three (four) digit code. In the archival documents indicate codes of «001» to «1553», where the numbering is not transparent, but has omissions (one missing number to several hundred).
The earliest known to me assigning digital codes airfields district belongs to the 08/01/1940, in the future it lasted.
It is in russian, but it just waits a translation of an enthusiast
http://may1945-pobeda.narod.ru/razved/san_avia41.htm
THX for the great work to K.B.Strelbitzki.