Electronik Warfare (EW)  on S-Boats of thh Federal Navy

ESM-Systems BBFPS

The boats "Silver Gull" (Silbermöwe), "Storm Gull" (Sturmmöwe), and "Wild Swan" (Wildschwan) of the British Baltic Fishery Protection Service (BBFPS) were eqipped with American communications- and electronik support-systems for detection and reconnaissance of Sovjetic radar- and communication sites along the coast of the Baltic.  Inormation about these systems is not available.

Mast of a S-Boat of BBFPS - Picture: Archives J. Prochnow

Transportable ESM-Receiver TRACER (VR-2)

Before the S-boats of classes 140, 141, and 149 were equipped with stationary systems for electronic warfare, i.e. radarwarningssystems (Electronic Support Means , ESM), the boats had transportable radarreconnaissance-receivers TRACER (VE-2), which provided information in X-band to an accuracy of two degrees and in S-band to four degrees that enemy-emissions were present. At any rate with the bearings of two or more units it was possible to determine a rather big aerea in which the enemy could be.

Datasheet of Bearable Radar-Receiver TRACER (VR-2) - Picture: Föreningen T121 Spica Vänner

Early in the 60es the boats of the Federal Navy got a ESM-systen from ELTRO (Elektro-Optik GmbH, Flensburg). It was a radar-warning-receiver which was able to detect foreign radar- and communicationwaves i frequency-ranges S- and X-band. The receiving-antenna was situated in an ESM-pot in the top of the mast. Identification of the detected radar was performed by the operator with help of available tables in communications-room 2 (on stb-side behind the open bridge).

ELTRO ESM-Pot at the Masttop of S-"Löwe" - Picture: Archives K. Scheuch

Boats of the 1. S-Squadron with ELTRO ESM-Pots - Picture: Archives J. Prochnow

The boats of class 142 were equipped with the ELTRO-systems during their construction.

EW-System DR 2000 SL

Originally the boats of class 148 were equipped with EW-Systems DR 2000 SL. About this system no information is available. Since the system was of only limited performance it was substituded by the EW-sytem (SARIE-1 by Thomson CSF. 

"S 41" with SARIE-1-Pot in the Masttop - Picture: Archives K. Scheuch

The antenna of the system was in the masttop. The received data and the results of the anaslysis were provided on a scope in the Ops-Room. An integration into PALIS was not performed.

The boats of class 143 were originally also equipped with the system SARIE-1.

SARIE-1 Antenna on "S 64" - Picture: ArchivesK. Scheuch

The SARIE-1 systems on the boats of classs 143 were integrated into AGIS, so that the bearing automatically appeared on the TBH and could be released for Link 11-transmission.

OCTOPUS

In the early 90es five boats of both the 3. and the 5.S-Squadron were retrofitted with the EW-System OCTOPUS. To provide space on the mast for the so called OCTOPUS-Pot the navigational radar was placed on a two-leg-bearing contstruction in front of the bridgehouse's roof.

The system provided for passiv detection and analysis of enemy-emitters and signals (ESM) and jamming of radarsystems (ECM) with high intensity.

Mast "S 48" - Picture: Archives K. Scheuch

OCTOPUS-Console on S48 "Löwe" - Picture: M. Rode

Presentation of the received data of the OCTOPUS-system was performed on the OCTOPUS-Console in the Ops-Room. Jamming was initiated from this console.

 The OCTOPUS-system was not integrated into PALIS of the boats of class 148.

With decommisssioning of the boats class 148 the boats of class 143 were retrofitted with the OCTOPUS-system. The system was integrated into AGIS. The received emitters were displayed as bearinglines on the TBH and could be released for Link 11-transmision.

As the picture below indicates S 67 "Sperber" was retrofitted with OCTOPUS, WOLKE and NSP-500.

WOLKE and HOT-DOG

As defence against incomming missiles the boats class 148 were fitted with chaff-system WOLKE and flaires HOT-DOG.

WOLKE emitted via a tube with exit in hight of the masttop silver foil threads which were to deceive a larger target to the searchhead of the missile.

For firing of heat-emitting flaires HOT-DOG the boats of classes 148, 143 and 143 A had six flair launching devices on either side of the B-deck, from which the flairs were started in order to divert the IR-searchhead of the incomming missile.

OCTOPUS-Pots, TRITON-G-Antenna, and WOLKE-Emitting Tube - Picture: M. Rode

Bb-HOT-DOG-Starters on S71 "Gepard" - Picture: K. Scheuch

The boats of class 143 were retrofitted with WOLKE after decommissioning of the boats of class 148.

HOT-DOGs were fired from the HOT-DOG-control-pannel in the Ops-Room.

HOT-DOG Remote Control Pannel in the Ops-Room of OPZ S71 "Gepard" - Picture: U Skrzypski

A secondary pannel from which HOT-DOGs could be launched was installed on the open bridge.

HOT-DOG Secondary Control Pannel on the open Bridge of S71 "Gepard" - Picture: Archives K. Scheuch

Bb-HOT-DOG-Launchers on S 48 "Löwe" - Picture: W. Loser

Operation of  WOLKE and HOT-DOG during the March Kiel-Warnemünde - Pictures: T. Kunzmann

FL 1800/ FL 1800 II

The boats of class 143 A were fitted with the EW-system FL 1800. FL 1800 was developed by company Rhode & Schwarz and became the standard EW-system of the German Navy.

The ESM-part consisted of four boxes under the radom of the  WM-27 which contained two antennafields each. The antennafields covered a frequency-range from 7,5 to 18 GHz for what 10 spiral antennas were available for each band. Thus the system could determine elevation and bearing precisely and build an exact picture of the situation.

The data were shown on the ESM-console in the EW-corner of the ops-room and after analysis of the emitter it was transmitted to the TBH as a bearingline.

In the yard-arms of the open bridge four additional antannafields were located, which by passive phase-controlled signalclubs with eight roamingfield tubes could perform jamming in the frequency-range from 7,5 to 18 GHz. Each signalclub could jam a single target. The effective emitting power was strong enough to cover the radar-crosssection of the boat. 

WM-27 and FL 1800 on S71 "Gepard" - Picture: T. Kunzmann

With the upgrade to FL 1800 II with hardware-enhancements and additional capability for pulsed hiss-jamming also a new capability became available to estimate the distance based on the amplitude of the emitter, a feature which made lauching of a RAM-missile against incomming missiles or aircarft possible . 

FL 1800-Console on S 76 "Frettchen" - Picture: Archives A. Günzler

The FL 1800 was fully integrated into AGIS of the boats class 143 A. The detected and analysed emitters could be given free for transmission via Link 11 so that also other participating units (PUs) could make use of the information.

Jamming of emitters was  initiated by the EW-console.