Name Pochtovy Draft 2.8 m Length 36 m | Decommissioned 1913 Launched 1908 Beam 3.2 m | |
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Displacement 134 tons surfaced146 tons submerged Propulsion 2 petrol engines 260 hp (190 kW) combined Speed 10.5 knots (19.4 km/h; 12.1 mph) surfaced6.2 knots (11 km/h; 7 mph) submerged | ||
Pochtovy (Russian: Почтовый) was a submarine built for the Imperial Russian Navy. The boat was designed by Drzewiecki and built at the Metal Works St Petersburg in 1908. She was funded by Public subscription.
This ship's machinery was a novel attempt at Air Independent Propulsion (AIP) using gasoline engines with air supplied by pressurised cylinders. Forty-five cylinders containing 350 cubic feet (9.9 m3) of air at 2500 psi could give the boat a 28-nautical-mile (52 km) submerged range on one engine. The exhaust gasses were vented via perforated pipe under the keel. The system proved reliable in trials but condensation problems and the tell-tale wake produced by the exhaust resulted in no further development and the boat was stricken in 1913.