Two-Hulled Flying Fish

Soviet MK-1 flying boat made its maiden flight on August 16, 1934
MK stands for "sea cruiser'.
This record-breaking aircraft was supposed to carry two 20-mm cannons, six 0.3-in MGs, 6000 kg bombs or 4 torpedoes.
Wingspan - 51,6 m. Two hulls. Six 830 HP engines.
Only one built.
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