1925 (14 Feb) first flight Warszawa to Bucharest, regular 3gr, 15gr and 50gr franking, appropriate cachet and markings, v.f. (Image)

Est.$150

1928 (30 Sep) four covers flown from Siniawka, Kuznica, Maloryta and Wasilkow to Warszawa, each franked with "Poczta Balonowa 1zl L.O.P.P." adhesive, used in combination with regular 5gr franking, tied by "Raid Balonow Kulistych" cds, with corresponding "Balon Lwow", "Balon Warszawa", "Balon Krakow" and "Balon Poznan" handstamps alongside, v.f., scarce (Image)

Est.$500

1938 (8 May) two covers flown from Moscice and Lawoczne to Katowice and Lodz, various frankings and cachets, with corresponding "Balon Mestwin" and "Balon Syrena" handstamps, v.f. (Image)

Est.$250

1939 (9 Sep) two cards "Gordon Bennett", with Belgian stamps and Poczta Balonowa labels, each with appropriate markings, including "Anulowany z Powodu Wojny" (annulled due to war), v.f. (Image)

Est.$150