[size=5]
Aliscafo (Hydrofoils)[/size]
Experimentale 75ton surface piercing
Intended armament is 1x47mm, 3x20mm Oerlikon FFL in single mounts. 2x533mm torpedoes are carried.
2x1150hp Isotta-Fraschini Asso engines. 2-shafts and 2 propellors. Speeds of up to 40knts have been attained. The craft is stable in head seas but comes off the foils with a following sea.
Experimentale AS-1 and AS-2 200ton surface piercing
Intended armament is 4x37mm, 4x25mm 4x600mm TT
1 Boiler 2 Geared Steam turbines 10,000shp on 2 shafts
1 Cruising turbine, 500shp 1 shaft
After trials throughout 1930 the lightweight turbines were found to be far too delicate, unreliable and incapable of producing enough power. Large problems were experienced when launching torpedoes at foilborne speed. The maximum speed was found to be about the same as that of the torpedoes. In addition the torpedoes had a prospensity to hit the foils on launching. As a result, the torpedoes were replaced in refit and relocated to the stern. AS - 1 was to launch the torpedoes over the stern, AS - 2 having a much more untested method which is still in experimental stages.
After trials throughout 1930 both ships were re-engined.
AS-1 received Isotta-Fraschini petrol engines, 16 linked to 2 shafts giving 18.400shp total.
AS-2 received Guidoni-Type Diesel engines, 4 linked to 2 shafts giving 20.000shp.
Trials with the new motors continue and it is undecided which shall be chosen for production.
Problems were encountered with launching torpedoes over the stern. They were found to be susceptible to the large wake created by the props which affected the gyroscopes.
AS - 2 after being refitted with Diesels and new torpedo launchers.
AS - 2 under high speed trials in Golfo di Taranto.
AS.3
A development vessel built in late 1931. First fitted with armament. Less emphasis on performance after extensive trials with previous vessels. 4xGuidoni diesels give 16000shp which is equivalent to about 50knts maximum. Armament fitted is 1 quadruple 37/54, two single 25mm, 4x600mm torpedo tubes and 6x50kg DC on the stern. The torpedoes are in semi-fixed tubes facing forwards each side of the bridge. Max speed for launching is currently fixed at 35knts.
AS.5
Three pre-production vessels laid down in 1933. Less extreme than previous types. More emphasis on reliability and strength. Straight foils are easier to construct and maintain. 2xFiat-Guidoni Diesels gives 10,000shp for 45-50knts sustained. Twin funnels/intakes aft. More enclosed bridge structure. 1x100/47 mounted forwards. 2xtwin 25mm amidships. 4x450S aft.