Cover franked with 2 x 1930 5c on 10c orange AIR issue (SG 238) tied by PANAMA cds dated MAR 10 1930. Flown on the PANAMA - COSTA RICA first flight with boxed 'AGENCIA POSTAL DE PANAMA PRIMER VUELO PANAMA - COSTA RICA' first flight cachet in pink. Addressed to COSTA RICA with arrival cds dated 11 MAR 1930 on front. (Muller #38)