The SPL (Samolyet dlya Podvodnikh Lodok – aeroplane for submarine boats) (a.k.a. OSGA-101, and Gidro-1) was a submarine borne flying boat designed and built in the USSR from 1931.
The SPL (Samolyet dlya Podvodnikh Lodok – aeroplane for submarine boats) (a.k.a. OSGA-101, and Gidro-1) was a submarine borne flying boat designed and built in the USSR from 1931.