Japanese Stamps Digital Museum

芦ノ湖 << 1929年(昭和4年) ~ 1934年昭和9年) >> みほん 6-1-1

Ashinoko Air Mail Stamps Issued on 1929 (Showa4) ~ 1934 (Showa9) - Specimen -

Ashinoko Air Mail Stamps Issued on 1929 (Showa4) ~ 1934 (Showa9) - Specimen - As was the case with the flight mail trials in Japan in 1919 (Taisho 8), flight mail in other countries developed dramatically during this period. Japan promulgated the "Air Mail Regulations" in 1929 and launched Japan Domestic Air Mail. In October of the same year, the Ministry of Communications issued four types of airmail stamps. The design is a three-engine Hooker airplane that flies over Lake Ashi. However, due to the subse- quent increase in postage, these airmail stamps were abolished in 1938, waiting for the newly issued ‛Kiji’(pheasant) airmail after the war.

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The above is only true for specimen stamps.
For more information and official printed stamps, see this.
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