Between 1935 and 1939 he was the commanding officer (in the rank of Lieutenant-Commander) of ORP Jaskółka, a Polish minesweeper and minelayer.
After boarding naval mines from a floating depot, the flotilla headed for Hel Peninsula, assisted by ORP Wicher and several smaller vessels (among them Łomidze's former ship Jaskółka).
En route she was attacked by a squadron of 33 German Ju 87B dive bombers and hit with several bombs.
Although the damages were minor, the ship lost 22 sailors, including Commander Stefan Kwiatkowski in what became known as the battle of the Gdańsk Bay.
During the final days of the Polish defence of Pomerania, Łomidze, along with several other naval officers, crossed the Baltic on a small fishing cutter.