1954, Provisionals, 24b. on 1l. overprint "airplane and year date", 25 copies in half a sheet with corner margins (upper half with sheet number), c.t.o. "Sana´a 31.5.62". Not listed in the catalogues. The history of the 1954 provisionals is not completely explored yet. There are diverse overprints on regular issues known. They probably were produced by the Ministry of Communications but never used officially. They are quite rare and not offered very often.