The Otomat is an anti-ship and coastal defence missile developed by the Italian company Oto Melara jointly with Matra and now made by MBDA. The name comes, for the first versions, from the name of the two builders ("Oto Melara" and "Matra") and, for the later versions, Teseo, from the Italian word for Theseus. The MILAS variant is an anti-submarine missile. In its latest version Mk/2E purchased by the Italian Navy is a medium range anti-ship and a land attack missile.
Origins The Otomat missile program started in 1967, the same year in which the Israeli destroyer Eilat was sunk by three Soviet-made P-15 Termit anti-ship missiles. This event raised awareness about the effectiveness of such weapons and prompted the development of similar systems in Western countries, such as the Harpoon in the United States. However, it is unknown whether the Otomat program started before or after the Eilat event.
The Otomat program was undertaken by the Italian Oto Melara corporation in cooperation with the French Matra Corporation. The aim was to develop an anti-ship missile powered by a turbofan which would allow more range and a heavier warhead than rocket-powered missiles then being developed in Europe such as the French Exocet and the German Kormoran. Trials started in 1971 and development of the Mk1 version of the Otomat officially ended in 1974.Lanzara, p. 34
However, at that time, the French Navy chose the wholly French Exocet over the Franco-Italian Otomat as its standard anti-ship missile. Thus, the Italian Navy remained as the only launch customer for the missile; it entered service in January 1976, before the commissioning of the warship intended to carry it, the .Lanzara, p. 32 These early Otomat missiles lacked a data link for over-the-horizon targeting, which limited its effective range to a similar figure to the Exocet. To solve this problem, development of an Mk2 version started in May 1973, with a first test launch in January 1974, development completed in 1976, and the first over-the-horizon launch in 1978. By the end of 1976 OTO Melara had reported that 210 Otomats had been sold: Italy 48, Peru 40, Venezuela 12, and Libya 110. Also at this time there were negotiations under way for the sale of 296 more missiles to various nations (i.e. Italy 48, Egypt 30, Venezuela 48, Libya 120, Indonesia 50).Ezio Bonsignore "The Italian Naval Exhibit" Aviation & Marine page 50 October 1976 published INTERCONAIR
A Mk2 Block II version was introduced in the 1980s, it featured folding wings so that the missile could now fit in a smaller launch box. This reduction in size allowed a doubling in the number of missiles carried, usually from four to eight. Even so, Otomat Mk2 Block II remained bulkier than contemporary versions of Harpoon and Exocet missiles due to its greater diameter and its boosters being fitted to its flanks instead of in the rear.
Description
The Otomat is a long-range anti-ship missile capable of reaching around at an average speed of . It is stored and launched in a fiberglass box which weighs fully loaded. This container has a rectangular shape to accommodate the fixed wings of the missile and an inclination of 15 degrees. At launch, the boosters propel the missile up to a height of before the main engine starts and a descent to is made. Otomat Mk2 missiles have a data-link for mid-course updates. They are designed to strike their targets in a dive or in a sea-skimming mode at an altitude of with a warhead capable piercing up to of steel. The warhead is designed to explode inside the ship with the force of the explosion directed to the bottom of the target ship.
Technical data are:Lanzara, p. 38 length, diameter, 1.35 wingspan, launch weight.
The mid-fuselage fuel tank has a capacity of . Behind the fuel tank is a Turboméca TR-281 Arbizon III engine, a simple turbo-jet. The twin ROXEL boosters weigh each, and provide an acceleration of 6 g for four seconds. The Arbizon III has and is about 50% more powerful than the Harpoon's engine, a Willis turbojet that has .
Unusually, the Otomat has four air intakes (for comparison, Harpoon and Tomahawk missiles have only one), all placed forward the wings at mid-fuselage. This contributes to the characteristic, complex shape of the missile.
Power available has made possible to fit in the bulky fuselage a high fuel reserve, heavy warhead and a data-link (Mk 2 model) to receive updates, at least once when in flight to the target.
The flight controls are four foldable steerable main wingszand four tail control winglets. Structure is made of light alloys, mainly aluminium. The Radar active seeker has a range, in the Italian version, of around with a medium-sized target, but usually it is activated at a shorter distance (see typical mission).
The warhead is in the front, behind the radar section and in front of the radio-altimeter and some other electronic systems. The HE warhead is of the semi-armor-piercing type and has a Hertol type filler (for comparison, Kormoran missiles have warheads, is the HE main charge, plus 16 radial small charges to explode well inside the ship after the main explosion, and the armor-piercing capability is around ).
In a typical layout, there are 4–8 fiberglass boxes, with the missile inside, held by a rail in the roof. The overall weight is .Lanzara, p. 39
Data-links are included in the TESEO or ERATO control systems. ERATO has computerized consoles CLIO, while TESEO has MM/OJ-791 consoles, weighing with electric power requirement. The Data-link is called the PRT400 system, and the components are the PTR402 designation for missile (as receiver), PRT401 designation for the transmitter (shipborn) or PTR403 (carried by helicopter). Other systems that can be fitted include the PRT404 system for light ships and the PRT405 system for helicopters.
Overall strengths of this missile are long range, speed, sea-skimming capabilities and a powerful warhead.
Weakness are the need for a helicopter for mid-course guidance and a quite difficult uplink in the TESEO system (at least in the original model), big dimensions (affecting radar cross section RCS and IR signature), the lack of complex manoeuvres (synchronization of attacks, re-engagement capabilities, ECCM capability not up to current standards and never publicized), and the availability of surface versions only: no submarine and aircraft versions were developed.
This caused problems to the services that acquired these anti-ship missiles: Italian forces use Otomat (ships), Marte (helicopters), Kormoran (Tornados), Harpoons (not confirmed for submarines). Given the necessity to buy other totally different missile systems, many customers simply bought a 'family of missile systems' as in the Harpoon series and the Exocet family with obvious operative and economic advantages.
Typical mission
In terms of technology and operability, this missile presents a very powerful anti-ship weapon and perhaps the most powerful of all modern western anti-ship missiles that have a mid course data-link.
No particular maneuvers are required by the ship; the missiles are capable of changing course after the launch up to 200° so all the missiles in the ship could be used against the same target in one attack.
This allows for quick reaction times, as the ship does not need to change direction to reveal the missile batteries. This allows the ship to fire all missiles against a target regardless of where they are placed aboard.
Flight The boosters made by ROXEL are positioned at the flanks. They give enough speed to allow the turbojet to start, while the wings open. Four seconds later, once the missile reaches a 250 m/s speed and 200 m height, it stabilizes its flight and descends to 20 m, cruising at low altitude. At this time, the auto-pilot and the altimeter hold the right directions to the target. The missile flies at around 1,000 km/h, controlled with the four cross winglets in the aft, which are behind the main fixed wings to stabilize the weapon.
Mid-course update is possible with several systems. This weapon system is called TESEO (only the missile is called Otomat) in the Italian Navy, and the course correction is given by two channels: by the ship itself (TG-1) and with external sources, available in the Agusta Bell AB-212 ASW helicopter's final production batch (TG-2).
While the missiles flies it receive the input at mid-course. Then, at only 6 km from the target, it activates the onboard radar to reduce reaction time from the target. There are two models: the simpler ST-2 made by SMA (Italian missiles) and the more complex and ambitious CSF 'Col vert', for French made missiles. The CSF is only for export, since the French Navy has not adopted them. There is a large difference in the seekers. The first is a one axis, two dimensional radar system: the weapon simply continues to fly to the ship, with the altitude falling from 20 m to, in good sea conditions, 2-3m. The warhead is heavy, weighing 210 kg (Exocet 165, Harpoon 227) and the explosive blast is focused downward, attempting to blast a hole in the ship's bottom sinking rather than just damaging the vessel. The Col Vert version of the missile performs pop up flight to 180 m at around 2 km from the target and then dives on the ship, aiming at the decks to maximize damage.
The Col Vert version seems to have suffered problems in service with issues from sea state wave clutter. The popup and final dive attack of the Col Vert version of Otomat were designed to fool CIWS fire solutions. A similar approach was used in the US Harpoon system, then abandoned. Sensors in this variant are more complex and costly than the simpler sea skimming models, and while more capable to penetrate air defenses, they may have not shown a decisive superiority, even if technologically more sophisticated.
Mid-course datalink
The mid-course data uplink was originally provided by two different systems: TESEO and ERATO.
The ERATO (Extended Range Air Targeting for Otomat) system, used by the Al-Madinah class frigates, is the French version for mid-course guidance of the Otomat missile. In this case updated target information is provided to the ship which controls up to 16 missiles. This allows a multi-ship launch (Madinas have eight missiles each) and single ship control of an Otomat salvo for coordinated attack. The downside of this system is that the Otomat missile must rise to a 900-meter altitude to achieve uplink data. This could theoretically warn a target ship of the impending attack, but there are few possibilities to notice such small missiles at ranges of more than a few dozen kilometers. Maximum range for data-link is 100 km, limiting somewhat the missile's maximum range. It is possible to send up to six corrections for each missile, and attack up to six different targets at once. Consoles are called CLIO, integrated with ship's combat system.
TESEO is used by the Italian Navy and does not need altitude variations in the flight for missiles.
The limiting factor with the Otomat as incorporated in the TESEO system is that the AB-212 ASW Helo platform used for update has a limited radar range of no more than 60 km (with a 2,000 m2 RCS target, typically a frigate or destroyer), and will be hovering and stationary to allow the missile to fly under it and guide Otomat to its target. If the target ship has a medium-range SAM suite like RIM-66 Standard missiles, and is aware of the danger (with radar and ESM suites), the AB-212 Helo's lifespan could be limited to mere seconds, as it is much bigger than anti-ship missiles.
TESEO system requires that the missile fly under the helicopter, allowing the engagement of only one target at a time (even if with two missiles), the missiles must be launched to helicopter and so, this one must fly practically fixed for several minutes, while the missiles must fly a longer flight path, being this launch a non linear flight path.