Description:

1928 (May 31) USA-Australia #122a cover addressed to Lieut CTP Ulm flown by Sir Charles Kingsford Smith, Charles Ulm, J Warner & H Lyon on the first crossing of the Pacific by air endorsed "Honolulu to Australia per the 'Southern Cross'/This Envelope was carried across the Pacific Ocean from Hawaii to Australia" signed "Jas W Warner, Radio Opr" and also signed "C Kingsford Smith" and "Lieut Comdr Harry W Lyon, Navigator" alongside on face, franked with KGV 1½d black-brown tied Sydney '15JE28' datestamp on arrival, very fine condition, Cat $12,500. [6 flown; with 1973 Philatelic Foundation, New York certificate]