Sachsen-class frigate

The F124 Sachsen class is Germany's latest class of highly advanced air-defense frigates. The design of the Sachsen class frigate is based on that of the F123 Brandenburg class but with enhanced stealth features intended to deceive any opponent's radar and acoustic sensors and incorporate also the advanced multifunction radar APAR as well as the SMART-L long-range radar which is claimed to be capable of detecting stealth aircraft and stealth missiles. Although designated as frigates, they are in capability and size comparable to destroyers.

At €2.1 billion for only three ships, this was one of the most expensive ship building programs of the German Navy. They are similar to the Dutch De Zeven Provinciën class frigates. Both the Sachsen class and the De Zeven Provinciën class frigates are based on the use of a common primary anti-air warfare system built around the APAR and SMART-L radars and the area-defence SM-2 Block IIIA and point-defence Evolved Sea Sparrow Missile (ESSM) surface-to-air missiles.

In June 1996 the German government contracted for three ships with an option on a fourth that was provisionally to have been named as the Thüringen, but the option for this fourth ship was not taken up.

The F124 class frigates are larger and much more capable in all aspects than the Lütjens class destroyers, which they replaced.

General characteristics and machinery


The ships of the Sachsen class are 132.15 m long at the waterline and 143 m long overall. They have a beam of 17.44 m and a draft of 5 m, though the draft increases to 7 m at the sonar array in the bulbous bow. They displace 5690 LT at full load. Steering is controlled by a single roll-stabilized rudder; the ships have a turning radius of 570 m. The frigates have a crew of 38 officers, 64 petty officers, and 140 enlisted sailors. They have accommodations for an additional thirteen officers and sailors as part of a squadron commander's staff, and they have crew provisions for female sailors. The ships can remain at sea for 21 days at a time.

The ships' hulls were designed on the pattern of the previous to allow for great commonality of parts to reduce maintenance costs; they were built using MEKO modular construction and incorporate seven watertight compartments. The primary improvement over the earlier vessels is significantly the reduced radar signature. The ships were designed with a capacity for an extra 270 LT of weight, to allow for future additions of new weapons and sensors without compromising the ships' efficiency.

The ships of the Sachsen class are equipped with a combined diesel and gas (CODAG) propulsion system. The two operating shafts work independently. The diesel engines are installed in a non-walkable sound-proof capsule. The shafts drive two five-bladed variable pitch propellers. The GE7 LM2500 PF/MLG gas turbine is rated at 31500 shp and the MTU 20V 1163 TB93 diesels provide a combined 20100 bhp. The total 51600 hp propulsion system provides a top speed of 29 kn; while operating the diesels only, the ships can cruise for 4000 nmi at a speed of 18 kn. The ships are equipped with four 1,000 Kilowatt diesel generators that operate at 400 Volts (V) and 115 V.

Armament
These ships were optimized for the anti-air warfare role. The primary anti-air weapons are the 32-cell Mk 41 Mod 10 vertical launching system, equipped with twenty-four SM-2 Block IIIA missiles and thirty-two Evolved Sea Sparrow missiles. Point-defense against cruise missiles is provided by a pair of 21-round Rolling Airframe Missile launchers. The ships are also equipped with two four-cell RGM-84 Harpoon anti-ship missile launchers.

For defense against submarines, the frigates carry two triple-launchers for the 324 mm MU90 Impact torpedoes. The ships also carry a variety of guns, including one dual-purpose 62-caliber 76 mm gun manufactured by OTO Melara. They are also armed with two Rheinmetall 27 mm MLG 27 remote-controlled autocannons in single mounts.

In January 2003, Hamburg had a modified Panzerhaubitze 2000 turret with a 155 mm gun fitted experimentally for the Modular Naval Artillery Concept. The experiment was a feasibility study for the projected F125-class frigate. The gun had a range of 40 nmi and a rate of fire of 10 rounds per minute.

Sachsen and her sister ships are equipped with a flight deck and hangar that can accommodate two Super Lynx or NH90 helicopters. The flight deck is rated to accommodate a 15 MT helicopter in conditions up to sea state 6. The helicopter handling system from MBB-Förder und Hebesysteme uses laser guided and computer controlled manipulator arms to secure the helicopter after landing.

Sensors and countermeasures


For this role the ships are equipped with an advanced sensor and weapons suite. The primary sensors for this role are the long range surveillance radar SMART-L and the multi-function radar APAR. The SMART-L and APAR are highly complementary, in the sense that SMART-L is a D band radar providing very long range surveillance while APAR is an I band radar providing precise target tracking, a highly capable horizon search capability, and missile guidance using the Interrupted Continuous Wave Illumination (ICWI) technique, thus allowing guidance of 32 semi-active radar homing missiles in flight simultaneously, including 16 in the terminal guidance phase.

The radars include the Thales Nederland SMART-L long-range surveillance radar, the Thales Nederland APAR multi-function radar, and two STN Atlas 9600-M ARPA navigation radars.

The STN Atlas MSP 500 electro-optical fire control system provides target acquisition and tracking for the main gun. The bow sonar is the STN Atlas Elektronik DSQS-24B.

The ship's electronic countermeasures suite includes an EADS Systems and Defence Electronics FL1800 SII ECM system and six Sippican Hycor SuperRBOC launchers which fire chaff and flares. Electronic support measures are provided by EADS Systems and Defence Electronics Maigret CESM (Communications ESM).

Service history


All three vessels form part of the ''2. Fregattengeschwader (2nd Frigate Squadron'') based in Wilhelmshaven.

In August 2004, the Sachsen completed a series of live missile firings at the Point Mugu missile launch range off the coast of California that included a total of 11 ESSM and 10 SM-2 Block IIIA missiles. The tests included firings against target drones such as the Northrop Grumman BQM-74E Chukar III and Teledyne Ryan BQM-34S Firebee I, as well as against missile targets such as the Beech AQM-37C and air-launched Kormoran 1 anti-ship missiles.

End of March in 2013 The Hamburg (F220) became the first German ship to fully integrate into an American carrier strike group. It is commanded by Cmdr. Ralf Kuchler who hopes along with Rear Adm. Michael Manazir (Commander of Carrier Strike Group 8) that it is the beginning of a long partnership between the two countries. While this is the first time a German ship has been part of a carrier strike group, it is not the first time one has trained and deployed with American ships. FGS Hessen (F221) completed interoperability exercises and deployed with USS Harry S. Truman (CVN 75) in 2010, but detached in the Mediterranean Sea. German ships routinely collaborate with American ships in the European Union's Operation Atalanta, an anti-piracy mission around the Horn of Africa, as Hamburg did in 2011.