[WWII] Spica-class torpedo boat (Italy)

[copeab]

Spica-class torpedo boat (destroyer escort)
Copyright 2010 by Brandon Cope

The Spica-class ships were built from 1934-37 and were used extensively in WWII primarily protecting transports running between Italy and North Africa. They also had an anti-submarine capability and served as minelayers, minesweepers and, on rare occasions, a troop transport. The Circe may have been the most successful in the class, participating in the sinking of four British submarines, but was lost in a collision on November 27, 1942..

Thirty-two ships were built, two of which were transferred to Sweden in 1940. Of the remaining 30, 23 were lost in action. Despite this high loss rate, they gave a good account of themselves in combat. While called torpedo boats by the Italians, these ships were more properly light destroyers or destroyer escorts.

The crew is normally 116 men. The ship uses 850 gallons of fuel oil per hour.

Subassemblies: Light Destroyer chassis +9, waterproofed Medium Conning superstructure +5, three partial rotation Large AFV turrets #1-3 +3, four full rotation Medium Weapon open mount #1-4, two full rotation Small Weapon open mounts #5-6 +0, two full-rotation Mini Weapon open mounts #7-8 +0 , two partial rotation Small TD open mount #9-10 +4.
P&P: 14,168 kW steam turbine w/2x7,084-kW screw propellers, 78,000-gallon standard fuel tank; 40,000-kWs batteries
Occ: 8 NCS Sup, 6 NCS Body, 2 NCS each turret
Cargo: 200 Body

Armor
Body: F 4/90, other 4/30
Superstructure: 4/30
100mm mounts: FRLT 4/30, B/U 0/0
20mm mounts: F 4/25

Armament
3x105mm Medium DP Guns/100mm Mod 35 [Tur1-3:F) (200 each)
8x20mm Long Ground ACs/Breda-SAFAT Mod 35 [OM#1-4:F] (2000 each)
2x20mm Long Ground ACs/Breda-SAFAT Mod 35 [OM#5-6:F] (2000 each)
2xVery Long Ground HMG/13.2mm Breda-SAFAT Mod 31 [OM#7-8:F] (2000 each)
2x450mm torpedo tubes [OM#9-10:F] (4 total).
2xdepth charge/mine racks [Body:T, facing R] (20 mines)

Equipment
Body: 500 bilge, 10 bilge pumps, 200 cargo, 2x1-ton cranes (for torpedoes), 5 fire extinguishers, 110 hammocks, 7 cabins, 8 crew stations, 2 hospital beds, 125 man environmental system, 3,600 man/days provisions, precision navigation instruments, very large radio transmitter and very large radio receiver, radio direction finder, 2 mile passive sonar, workshop, minesweeping gear. Superstructure: Autopilot, 8 crew stations, precision navigation instruments, fire extinguisher, 2 cabins. OM1-8: Universal mount.

Statistics
Size: 274'x27'x45'
Payload:* 350 tons
Lwt:* 1,020 tons
Volume: 15,000
Maint.: 11 hours
Price: $307,000

HT: 12
HP: 75,000 [body], 1,200 [superstructure], 285 [turret, open mounts 7-8], 75 [open mount 1-4], 45 [open mount 5-6]

wSpeed: 39
wAccel: 2
wDecel: 0.5(1)
wMR: .02
wSR: 5
Draft: 8'
Floatation Rating: 1,800 tons

Design Notes
The historical displacement of 1,020 tons was used to calculate performance data. Design draft was 11'; the historical number was used instead.

The ships originally had their torpedoes in four single mounts, but this was quickly changed after the ships entered service. Depending on the mission, up to 20 mines could be carried or replaced with an equivalent weight of depth charges.

[Bill Cameron]

Brandon,

Thank you very much for this.

When the WW2 forum was folded into this one, I'd hoped you'd still post your excellent vehicle designs. It looks as if crossing my fingers and muttering tht cantrip worked!

Thank you again.


Regards,
Bill

[Michele]

Nice work, thank you.

My preferred source says 101 crewmen, but maybe the higher number you have includes a wartime increase.

"Torpediniera" in Italian means something like "torpedo ship". A "torpedo boat" would be called "motosilurante" (Confusing, I know; a "torpedo" was called both "torpedine" and more commonly "siluro").

In practice, they carried out ASW escort duties, and weren't so bad against aircraft attacking convoys, either.

One thing worth mentioning is that the Regia Marina had a good reason for liking this class, and this size of warships. Apart from the fact that they could (more or less, and in the Med better than in an Ocean) carry out the job of something heavier (a destroyer), and for a smaller price tag. The fact is that vessels up to 610 tons were under no limitation at all according to the London Naval Treaty. Every signatory could build as many as they wanted.

[copeab]

Originally Posted by Michele

My preferred source says 101 crewmen, but maybe the higher number you have includes a wartime increase.

On the surface ships I've done so far, I've fount quite a but of disagreement on exact crew sizes. I think in this case '116' was what both my print sources listed.

In practice, they carried out ASW escort duties, and weren't so bad against aircraft attacking convoys, either.

I noticed that one participated in downing for British aircraft in one battle.

The only significant criticism I read for the class was the use of 450mm torpedoes, at a time when virtually everyone else had moved on to 533mm torpedoes as their standard.

My major problem with this class was the ASW armament. Both my print sources said they could carry up to 20 mines but hardly mentioned depth charges. Online sources, OTOH, mentioned depth charges (in at least one case depth charge _throwers_) but didn't mention mines. One source did mention both, but didn't give numbers. So, my write-up in this respect was left a bit vague.

At some point I plan to do the Gabbiano-class corvettes. While on paper they appear quite inferior to the Spica-class, sources seem to indicate they were actually highly thought of by the Italian navy.