Thailand. (Goodwill Mission Flight to Hanoi). 1930. Illustrated Registered Air Mail envelope endorsed 'Bangkok - Hanoi' addressed to 'Banque de l' Indochine, Hanoi' bearing SG 233, 10s orange and black, SG 234, 15s carmine and SG 236, 50s black and orange brown tied by Bangkok GPO date stamp '30th Dec 30' with matching registration label, framed 'Par Avion; and boxed 'Bangkok - Hanoi Goodwill Flight/ December 31, 1930' in carmine on face with Hanoi arrival '31/12' on reverse.
"Goodwill Mission" flight by Siamese Army planes to Hanoi, Indo-China special Airmail letter rate for the "Goodwill Flight" of 60 satang plus 15 satang registration fee.