[Pibwl]

Just a 3 cents, to make things clear: Polish "dywizjon" unit is not a Division (big land army unit, which is "dywizja" in Polish - there were air divisions in USSR only), but a name used in air force or cavalry for a battalion-size unit. In the air force it is traditionally translated as Squadron - and such names were adopted in Polish Air Force in Great Britain for squadrons (although some say, that Squadron should be in fact "eskadra" in Polish, and they are right - these words have the same origin and are both equivalent of French Escadrille and Italian Squadriglia).

In Polish pre-war aviation, eskadra had 10 fighters, and two eskadras formed dywizjon.

"Klucz" is the smallest section, an equivalent of Flight, usually with 3 aircraft.