Croatian submarine Velebit (P-01)

Velebit (pennant number P-01) was a modified Una-class midget submarine and the only submarine to see service with the Croatian Navy. It was built for the Yugoslav Navy during the 1980s where it was named Soca. At the outbreak of the Croatian War of Independence Soca was being overhauled in the Brodogradilište specijalnih objekata division of Brodosplit shipyard in Split, Croatia. Although stripped of all equipment, it was preserved from the retreating Yugoslav forces by the shipyard workers.

With modifications that were aimed at improving the ships endurance by including a diesel generator, it was launched as Velebit (P-01) in 1996. A few years later it was out of service because of the need to acquire a new set of batteries, which in turn, never happened. After unsuccessful attempts of selling it to a foreign buyer, it was offered to various museums in Croatia with a final destination still pending.

Croatian submarine Velebit (P-01)
Class Ship
Type Submarine
Manufacturer Brodosplit
Origin Yugoslavia (Serbia)
Country Name Origin Year
Yugoslavia (Serbia) 1991
Country Name Operational Year Retirement Year
Croatia 1991 2005 View
Yugoslavia (Serbia) 1991 View
ManufacturerName Production From Production To Quantity
Brodosplit 1 View

Velebit was completed as Soca in 1987 at the Brodogradilište specijalnih objekata division of Brodosplit shipyard in Split, Croatia, as the fourth boat in its class. It measures 21.09 metres (69.2 feet) in length, has a draft of 2.4 m (7.9 ft), a 2.7 m (8.9 ft) beam and displaces 88 tonnes (87 long tons) when surfaced or 98.5 tonnes (96.9 long tons) when submerged. It was constructed as a single hull design with the internal compartment divided into three sections: forward (command/steering) position, exit chamber and the propulsion section in the back. During underwater operations two battery groups with a total of 256 cells power two 20 kW Koncar electric motors mounted on a single shaft that spins a five blade propeller. Surface propulsion and battery recharging is provided by a single diesel generator.

Maximum speed is eight knots (15 kilometres per hour; 9.2 miles per hour) underwater and seven knots (13 kilometres per hour; 8.1 miles per hour) surfaced. The boat's range is 250 nautical miles (460 kilometres; 290 miles) with a speed of four knots (7.4 kilometres per hour; 4.6 miles per hour). It has an underwater endurance of up to 6–7 days which is an improvement compared to 96 hours of other Una-class boats. Maximum diving depth is 120 metres (390 ft).

Because the class was designed with reconnaissance, small scale minelaying and special operations in mind, it does not possess any offensive weapons such as torpedos. The submarine was to use its small dimensions to easily maneuver in the relatively shallow waters of the Adriatic sea, staying undetected and transporting up to six special forces personnel who had 6–12 limpet mines and four AIM-M70 (M70/1) bottom mines or four R-1 submersibles at their disposal. Velebit had a crew of four.

Before the Croatian War of Independence Velebit served with the 88th Submarine Flotilla of the Yugoslav Navy entering service during the late 1980s. Velebit, then named Soca, was like other Una-class submarines, named after rivers in Yugoslavia. In 1991, it was being overhauled in Brodogradilište specijalnih objekata until the beginning of the war, when Croatian forces captured it. In 1993, Brodarski Institut (BI) of Zagreb started a modification program to improve the operational capabilities of the submarine captured two years earlier. The hull was lengthend to create space needed for the installation of a single MTU 105 kW diesel generator, a feature the original Una-class design lacked. A new steering system developed by BI was also installed.

It was recommissioned as Velebit in 1996. According to the 2007 edition of The Naval Institute Guide to Combat Fleets of the World, Velebit was fitted with a STN-Atlas Elektronik PP-10 active and PSU-1-2 passive sonar and a portable navigational radar may have been used on board along with the GPS. The claim is contradicted by other sources with news reports stating the submarine was completed without an active sonar, effectively being "blind" underwater. During the 1990s Velebit had the pennant number "3" painted on its side. After the existing battery set needed for underwater propulsion expired and needed replacement, crew training and boat operations were limited to surface drives.

Career (Yugoslavia)
Name: Soca
Builder: Brodogradilište specijalnih objekata,Split
Homeport: Lora Naval Base, Split
Identification: P-914
Captured: 1991
Fate: Captured by the Croatian National Guard during an overhaul
Career (Croatia)
Name: Velebit
Acquired: 1991
Out of service: 2005
Renamed: 1996
Refit: 1996
Struck: 2006
Homeport: Lora Naval Base, Split
Identification: P-01
Fate: Raised from the sea and stored in Lora Naval Base, declared redundant
General characteristics
Displacement: Surfaced: 88 tonnes (87 long tons)
Submerged: 98.5 tonnes (96.9 long tons)
Length: 21.09 m (69.2 ft)
Beam: 2.7 m (8.9 ft)
Draft: 2.4 m (7.9 ft)
Propulsion: 2×20 kW electric motors
1×105 kW diesel generator
Range: 250 nmi (460 km; 290 mi) at 4 kn (7.4 km/h; 4.6 mph)
Endurance: 6–7 days
Crew: 4 + 6 special forces
Armament: 4 × R-1 swimmer delivery vehicles
4 × AIM-70 bottom mines

End notes