The Zapal was a Russian patrol vessel of 500 tons displacement launched in 1935. The Zapal was powered by diesel engines providing a top speed of 16 knots, and was armed with one 4 inch gun; four 37 mm anti-aircraft guns and was fitted for mine laying and mine sweeping. Research Zapal
 
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert