Compact: 736 HE rounds on Type A mount or 444 HE rounds on Type B mount
Single Fast Forty: Dual feed mechanism with 144 HE or APFSDS rounds
Twin Fast Forty: Dual feed mechanism with 736 HE rounds & 200 APFSDS rounds on Type A mount or 444 HE rounds & 200 APFSDS rounds on Type B mount
Nobong: Dual feed mechanism (optional) with 704 ready-to-fire round
Marlin: Dual feed mechanism with 80 ready-to-fire round
DARDO ("Dart" in Italian) originally known as Breda Type-70,[1] also marketed as the OTO Twin 40L70 Compact,[2] is a close-in weapon system (CIWS) built by the Italian companies Breda and Oto Melara. It is composed of two Breda-built Bofors 40 mm firing high explosive (HE) shells, a fire-control radar (Alenia RTN-10X Orion) and a fire-control system (Alenia RTN-20X Orion and Dardo). It is the last of a long series of Italian anti-aircraft weapons derived from the Swedish Bofors 40 mm autocannons (mounted on Breda built gun mounts such as the Type 64, Type 106, Type 107, Type 564 and Type 520).
DARDO is installed in an enclosed turret with two different mounts: the Type A with 440-round internal and 292-round under-deck magazines; and Type B with only the 440-round internal magazine (Type B requires no deck penetration). However, the most recent OTO Twin 40L70 Compact's brochure nominates 736-round magazine for Type A and 444-round magazine for Type B, both feature deck non-deck penetration or with deck penetration.[2]
The newest Marlin 40 variant has no deck penetration, having a sole internal magazine for 80 ready-to-fire rounds.[3]
Other versions
Compact
The OTO Twin 40L70 Compact is the current marketing name for the DARDO. Option for a stealth cupola is available to reduce the gun mount's RCS.[2] They comes in Type A version with 736 round magazine & Type B version with 444 round magazine. Both the Type A and Type B mounting can be installed above-deck (non-penetrating) or with below-deck magazine. The compact mounting has maximum fire rate of 600 round/min (300 round/min × 2). A kit to upgrade Compact mounting to Fast Forty standard is available.[1]
Fast Forty
The Fast Forty is an improved version of the Compact mounting with a higher fire rate of 900 round/min (450 round/min × 2), dual magazine and dual feed mechanism to allow switching from High Explosive (HE) rounds to Armour-Piercing Fin-Stabilized Discarding Sabot (APFSDS) rounds when a target gets within 1,000 meters from the vessel. Produced in both Single-barrel (Single Fast Forty) and Twin-barrel (Twin Fast Forty) forms, the Fast Forty include a revision of some parts of the loading and breech mechanism and the use of titanium material to improve the performance compared to the Compact mounting. Ammunition magazine and feed arrangements of the Twin Fast Forty remain the same as the Compact but operate at a higher speed. The gun laying and acceleration rates were increased, while the barrel/barrels, are secured in a barrel guidance frames to improves accuracy.[1]
The Single Fast Forty has on-mounting ammunition capacity of only 144 round and are available in three types of mounting:
Type A: unmanned mounting, with all operation are done via remote control,
Type B: manned mounting, controlled and aimed by an on-turret operator,
Type C: unmanned mounting, feature an integral Micro Fire Control System (MFCS) with automatic tracking and fire-control computation.[1]
An optional 'Stealth' cupola that provided a significant reduction in the radar cross-section of the mounting are also available.[4]
Nobong
The DARDO were also manufactured in South Korea until 1992 by Daewoo who then developed their own mounting based on the DARDO with the magazine and feed capacity of 768 rounds and maximum fire rate of 600 round/min (300 round/min × 2) known as the Vespa 40mm L/70 K(T) mounting.[1][5] The mounting is currently marketed by S&T Dynamics as 40L/70K Nobong (노봉) and available with optional dual feed mechanism of 704 rounds magazine capacity.[5][6]
Marlin
The OTO Marlin 40 is the single-barrel, light-weight and no-deck-penetration derivative of the DARDO family, succeeding the Single Fast Forty variant. It is designed with high autonomy and fully-digitalized systems.[3] The mounting used to be known as OTO Melara Forty Light naval gun system.[7]
The system comes in a basic version called "Remotely Controlled" (RC), which can be managed by an external firing control system and in the advanced version called "Independent Line Of Sight" (ILOS), which can be operated autonomously via a local control console in addition to be fully controlled by Combat Management System. It also has selectable rate of fire ranging from single shot, 100 round/min and 300 round/min. The Marlin 40 may be fitted with an integrated hoist below-deck to enable the ammunition loading from covered position.[3][8]