1939 Polish Air Force markings

[stukapilot]

Chris, i guess u might save £40 this time
the book "Polish Air Force 1939 Through German Eyes. vol 1" by Andrzej Glass and Tomasz Kopanski has a brief introduction to those letter allocations, which is on page 10. i dunno if u have this book in your collection, my Chris, so i just kill some minutes to type those words from the book (abridged):

Allocation to a particular unit was marked on aircraft by applying code letters on wing undersurfaces. The codes were:
N for the 1 PL (Pułk Lotniczy - Air Regiment), K for the 2 PL, P for the 3 PL, T for the 4 PL, L for the 5 PL, and S for the 6 PL
training units used the following letters: 1 PL – A, 2 PL – E, 3 PL – F, 6 PL – J, SPL – D (Air Force Cadet Officers’ School), SPRL – R (Air Force Reserve Cadet Officers’ School), SP – U (Flying School at Ułęż), SPLdM – M (Air Force NCO School for Minors), Staff Training Flight (Sztabowa Eskadra Treningowa) – Z, Aviation Technical Institute (ITL) – W. Other underwing code letters included B, used by the SPLdM at Bydgoszcz

is this case closed now ))) for more info if u need, i'd like to take fotos or scanned pics )))