GENESISThe initial detailed design was developed by

Israel Shipyards Ltd, as a result of the IsraeliNavy (IN) needs for a fast patrol craft for pro-tecting the Israeli coast against the increasingterrorist threat. The design was carried out at theend of the 1980ies, due to the fact that Navieswere looking for new and improved solutionsfor the increasing threats to assets along the coastand for offshore facilities.

The protecting naval forces recognised thatthere was a global shift from local wars into ‘lowintensity conflicts’. At the same period also thetechnology of drilling at sea for oil and naturalgas was developed and the need to protect off-shore facilities and assets emerged.

The operational requirements were definedby ex-Israel Navy officers that were employed

at Israel Shipyards under the management ofAdmiral Ze’ev Almog (retired Commander ofthe IN), who all were well familiar with the INneeds. They have closely followed the devel-opment stages for ensuring a positive outcome.

The SHALDAG was developed and built byIsrael Shipyards Ltd. (ISL), and was upgradedseveral times over the years based on combatexperience gained. The original design was aim-ing at the ‘50-50’ formula, which means 50 tonsdisplacement and 50 knots speed. Since at thetime of development there was no similar craftthat could reach the 50 knots speed, there was aneed to construct a proto type. The firstSHALDAG MK I was therefore built in 1989and launched in 1990 to answer the concept offast and highly manoeuvrable craft, self financedby ISL.

Intensive series of sea trials were carried outto confirm that the defined performance wasindeed achieved. Over the years, and due to dif-ferent customers’ requirements, the full load dis-placement increased to 58 tons and speeddecreased to 47 knots.

ROLEThe SHALDAG Fast Patrol Craft is designed

to serve as a naval vessel as well as a BorderPolice (see figure 2) and Coast Guard unit. It isa combat proven craft, designed for coastaldefence and security, where high intercept speedand immediate response are required.

The SHALDAG mission roles include:• terrorist activities interdiction;• coastal and internal waterways defence

against illegal activities and smuggling ofdrugs and/or armaments;

• interception of hostile vessels;• fishery control;• protecting natural resources against unautho-

rised exploitation;• preventing illegal immigration;• offshore facilities protection;• search and rescue operations;• detecting and fighting sea pollution.

DESIGNThe craft is designed with outstanding per-

formance requirements in mind:• high acceleration enables the SHALDAG to

reach the speed of 40 knots in about 40 sec-onds, and high speed in rough seas – in orderto be faster than the targets;

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The SHALDAG is a combat provenvessel serving the Israeli Navy and oth-er navies and security forces for manyyears with the full satisfaction of cus-tomers. The SHALDAG is successful-ly serving in Europe, Asia and Africaand it is also marketed in Latin Ameri-ca, where Israel Shipyards has ongoingnegotiations with potential customers.Commander Israeli Navy (ret.) AviShahaf, provides details of the ship’sgenesis, role, design, ship data, propul-sion, sensors, armaments and other pay-load, and he answers questions ofNAVAL FORCES Editor-in-Chief.

WOLFGANG LEGIEN

SHALDAG FAST PATROL CRAFT

Fig. 1: SHALDAG –Full power on sea.(All photos courtesy of Israel Shipyard Ltd.)

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• outstanding manoeuvring performance suchas a turning diameter of about 150m at a speedof 40 knots, and to be able to quickly respondto an evasive/firing target;

• excellent sea keeping characteristics such asvery low slamming in all weather conditions,also to reduce crew fatigue and to improvecrew response abilities and firing;

• dry deck at all speeds for easier crew move-ment at sea;

• easy to operate and maintain;• high reliability with very low failure rate;• very shallow draft, in order to approach the

shore, and even beach it if required.

Therefore the SHALDAG was built as a ful-ly-planing deep-vee, hard chine craft with min-

imum resistance even in rough seas, with a pow-erful propulsion system comprised of two dieselengines and two water jets. A huge effort wasinvested in choosing the best propulsion system.

Compared to surface propelled vessel thewater-jet is more suitable for coastal defencemissions. Main advantages are:• no exposed propeller to hit underwater

objects;• lower noise and vibration level;• no cavitation, even at very high speeds;• the water-jet impeller is made of stainless

steel, stronger than the CuNiAl or NiAlbronze propellers;

• the manoeuvrability of a water-jet propelledboat is significantly better, due to the high sidethrust vector generated by the steering bucket;

• to change from ‘ahead’ to ‘astern’, there is noneed to disengage the gear, and therefore nochange of the rotation direction of the gear-box. The change is done much faster andsmoother, without need to stop the shaft;

• water-jets are designed to absorb maximumengine power at any boat speed, which resultsin longer engine life;

• reliability and lower maintenance require-ments.

Over the years ISL have developed varioustypes of the SHALDAG (MK II – MK V, seefigure 3), as a result of gained operational expe-rience and according to customers’ require-ments. Constant improvement of the platformswas a practical path through a continuous com-

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Avi Shahaf(Commander Israel Navy ret.) servedin the Israeli Navy between 1968 and1989 in various sea and HQ duties, as Commanding Officer of a Sa’ar-4missile boat, and as Flotilla Commanderof Fast Patrol Boats. From 1989 he wasMarketing Manager at Israel ShipyardsLtd. (ISL) and took up his presentposition as General Manager ISL. He holds a BA in Economics and BusinessAdministration of the University of Haifa.

NAVAL FORCES: What was the ideabehind developing the SHALDAG?AVI SHAHAF: The need for a fast PatrolCraft with very good manoeuvrability wasraised as a result of the world-wide changefrom regional and local wars to low intensi-ty confrontations, and the increase of the ter-ror threat. The common scenario was that theintruders were trying to hide their intentionsand become part of merchant or fishing boatsin their region. Due to these tactics, the pro-tective vessel needed to get very close forpositive identification, and then it wasexposed to their fire, as they were in a posi-

tion to be the first to open fire at close range.Hence there was a need for a very fast craft, withhigh manoeuvrability that has a very high ratioof firepower to displacement, for facing suchchallenges and offering very fast reaction. TheSHALDAG gave the answer to these needs andchanges of doctrines of coastal defence.

NAVAL FORCES: What was the deciding fac-tor for selecting a water-jet vice water piercingpropellers?

SHAHAF: A huge effort was invested in choos-ing the best propulsion system. Compared to sur-face propelled vessel the water-jet is more suit-able for coastal defence missions. Some of theadvantages are: (1) No exposed propeller to hitunderwater objects; (2) lower noise and vibra-tion levels; (3) no cavitation (if the size is prop-erly chosen); (4) the manoeuvrability of a water-jet propelled boat is superior; (5) water-jets aredesigned to absorb maximum engine power atany boat speed, which results in longer engine

SHALDAG: SYNONYM FOR AN UNSURPASSED ‘TAILOR-MADE’ FAST PATROL CRAFT

Fig. A: The SHALDAG is constructed as a ‘tailor-made’ craft and it is servicing different types of coastal defence units, such as Navies, Coast Guards, Border Police (Romanian Border Police SHALDAG seen here), Marine Police, Customs.

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Fig. 2: The SHALDAGFast Patrol Craft isdesigned to serve as a naval vessel aswell as a Marine Police(Romanian BorderPolice SHALDAG seen here) or Coast Guard unit.

bat experience feedback from the IN and otherusers. The craft is capable to operate up to seastate 4 with reduced performance and surviveup to sea state 6. Power is provided by two high

speed diesel engines, which drive two water-jetsincorporating steering and reversing gear.Propulsion machinery is located aft. The hull isdivided by four structural transverse watertight

bulkheads (in somedesigns five bulk-heads). The main

boat compartments are arranged as follows:• fore peak;• ammunition store & sanitary spaces;• accommodation for 10-14 crew members;

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life avoiding engine overload; (6) reliability andlower maintenance requirements.

NAVAL FORCES: It is understood that theSHALDAG comes in various designs, like anopen bridge aft of the command centre. Doesthis indicate that the customer is free to selectsuperstructure and internal deck configuration?SHAHAF: Indeed, the SHALDAG is con-structed as a ‘tailor-made’ craft and since it isservicing different types of coastal defence units(see figure A), such as Navies, Coast Guards,Border Police, Marine Police, Customs. It isdesigned to fulfil different requirements. TheSHALDAG is adjusted to the exact needs ofeach user. The adjustment can be done in termsof superstructure type, armament options, nav-igation and communications equipment, accom-modation design, number of crew members, andany other item.

NAVAL FORCES: Would it be possible to armthe SHALDAG with a small ship-ship missilesystem including a suitable sensor/director, vicethe TYPHOON gun with the search radar andelectro-optical director carried?SHAHAF: Yes, it is possible to arm theSHALDAG with additional components ofweapon suite such as short range missiles. It canbe positioned on the aft deck and be directedfrom the bridge with a suitable sensor. Theseshort range missiles can serve for attacking tar-gets at sea or on the coast line. It was alreadydone successfully by the SHALDAGs operatedby the Israeli Navy.

NAVAL FORCES: What makes the SHALDAGa leading design in the field of Fast Patrol Craft?

SHAHAF: We believe that the SHALDAG isthe best design for Fast Patrol Craft, due to itsvery high speed, excellent manoeuvrability,exceptional seakeeping, and the ability to carryup to 6 tons of combat payload. It is a combatproven vessel that is constantly upgraded basedon gained experience and feedback from theusers. Also the contribution of the advancedIsraeli Defence Industries helps making it thebest available solution for coastal defence. Atthe same time the maintenance of theSHALDAG and its systems is relatively verysimple and the craft is designed to be low-main-tenance.

NAVAL FORCES: What does the SHALDAG‘package’ include?SHAHAF: The SHALDAG is offered to cus-tomers as a ‘full package’ that includes trainingfor the operational and maintenance crew. The‘full package’ includes planned maintenanceprogramme (crew and depot levels), spare parts,documentation and drawings. The training isdone by ex-Israeli Navy officers and is offeredat the ISTC (Israel Shipyards Training Centre)and at the suppliers of main systems facilities.

NAVAL FORCES: Is there any need for extraprotection/armour of the SHALDAG againstbullets?SHAHAF: The SHALDAG is a very fast craftwith exceptional manoeuvrability. Add to thesethe fact that the SHALDAG’s armament is forranges of above 2,000 yards, our doctrine is thatthere is no need for extra protection or armour.The SHALDAG can be operated in a way thatwill keep it away from the target’s firing rangewhich is the best way to protect it (see figure B).

At the same time, if a customer insists on pro-tecting main equipment, this can be consid-ered.

NAVAL FORCES: Mr. Shahaf, thank youvery much for your detailed description ofthe SHALDAG, a product ISL and its userscan be proud of.

Fig. B: The SHALDAG is a very fast craftwith exceptional manoeuvrability. Add to these the fact that the SHALDAG’sarmament is for ranges of above 2,000 yards, our doctrine is that there is no need for extra protection or armour,says the General Manager of ISL.

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• auxiliary room (in some models);• engine room;• water-jet and steering compartment.

The hull and deck house are built of marinealuminium alloy welded construction withexcellent corrosion-resistant characteristics.Scantlings are in accordance with Lloyd’s Reg-ister Rules. The use of aluminium helps signif-icantly in reducing the weight of the craft. It isworth mentioning that construction of craft madeof 100 percent aluminium demands a very highlevel of professionalism, skill and experience –ISL has decades of experience in this field.

The hull is shaped with smooth lines bothabove and below the water line, offering exceptional handling even at high sea state (seefigure 4).

The hull watertight subdivision and compart-ment arrangement provide the ability to surviveunderwater damage of any compartment. Themain deck is continuous. The deckhouseincludes wheelhouse, mess room and galley. Theopen bridge is located above the closed bridgeand includes a helmsman position and ship con-trols.

The fact that the length-to-breadth ratio of thevessel is relatively low is one of the design fac-tors that provide high stability for the craft com-pared to similar boats. Other factors that con-tribute to the vessel high stability are: a sprayrail, hard chine hull, and a relatively low centreof gravity.

The boat is designed according to the Rulesand Regulations of Lloyd’s Register of Ship-ping.

Main propulsion is provided by two MTU16V2000 or 12V4000 diesel engines driving twoMJP 550DD or 650DD water-jets; these two dri-ve trains can be operated independently. In thepast, the vessels were equipped with DeutzMWM 620V16 engines and LIPS or KaMeWawater-jets. The reasons for the changes in typesof propulsion system are mainly customers’requirements and the need to adjust according-ly. The control of the propulsion system is fromthe wheel house and fly bridge with a capabili-ty to be controlled locally from the engine room.The efficiency of the water-jets was significantlyimproved over the years, and currently better

results with smaller and lighter jets are achieved.It is important to re-iterate that the jets are help-ing to achieve low maintenance levels for thecraft.

The sensor suite consists of a surface searchX-band radar for navigation and surveillance.Another standard sensor used on most of theSHALDAG Fast Patrol Craft is the multi-sen-sor stabilised electro-optical director for day andnight surveillance. It can be either theTOPLITE™ supplied by Rafael, POP™ suppliedby IAI, or any other light-weight E.O.D., and isused for surveillance and fire control of the maingun. It includes colour CCDs, generating visu-al and thermal images for day and night opera-tions, accurate line-of-sight positioning, laserrangefinder, tracker and designator.

The Integrated Navigation System with 24VDC supply includes the following features:GPS receiver and antenna; Echo-Sounder; AIS(Automatic Identification System), completesystem with transponder, display, VHF/GPSantenna; Navigation radar (X-band); ARPA

module; display of electronic maps; multi-func-tion 15” display units for the wheel house con-trol console.

Concerning the armament suite, traditional-ly ISL is offering naval vessels with high firepower for a relatively low displacement. TheSHALDAG is fitted with the required founda-tions to enable installing fore-deck and aft-deckguns, as well as heavy machine guns on the flybridge (port and starboard) and / or on the deck.The guns can be either the remotely controlledand stabilised TYPHOON or Mini-THY-PHOON guns, or manually operated guns andmachine guns. Of course a mix of both is alsopossible. Based on the above, the vessel can beoptionally fitted with the following armament:• 1x TYPHOON-type automatic stabilised and

remotely controlled 23/25mm gun, or simi-lar manual naval gun;

• 2x 12.7/ 7.62mm MINI-TYPHOON typeautomatic stabilised and remotely controlledheavy machine guns, or manual machineguns, on the fly bridge;

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Fig. 3: There are hardly two SHALDAG alike,with remotely controlled or manual main gun

systems forward, gun or other equipment aft,different fly-bridge configurations,

different boat length – they come as SHALDAG MKII to MKV, in Navy, Coast Guard,

or Border Police configurations.

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• 2x 12.7 / 7.62mm manual machine guns onthe aft deck;

• 2x 12.7/ 7.62mm manual machine guns on themain deck on the sides of the deckhouse (oneon each side);

• 1x 20-23mm naval manually operated gunmounted on the rear gun foundation near thetransom;

• 4-8 short-range 4-8 missiles (IAI LAHAT or equivalent).

The SHALDAG is fitted for optional payload alternatives, depending on customer’srequirements. This includes a suitable boat, suchas a 3.20m ZODIAC MK II or RHIB. The RHIBis up to 5.20m and can be either a rescue boat ofan approved type, or a fast patrol boat. When aRHIB is supplied the vessel includes a liftingand launching davit. 13,000 litres of fuel are carried, and 1,000 litres fresh water (the MK Valso has a desalination plant).

SUMMARYAs of today, the SHALDAG is constructed

on a ‘tailor-made’ basis in order to give fullresponse to any customer’s needs. The accom-modations of the craft are also adjusted to theexact number of crew members of each userand to the level they are defining.The accumulated combat experience and feed-back helped in designing and executing a largenumber of improvements over the years. Thehull was lengthened and was modified to specific requirements of the Israel Navy as wellas other customers. Adjustments were alsomade to the superstructure.

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Fig. 4: The SHALDAG’s deep-vee hull is shaped with smooth lines both above and below the water line,

offering exceptional handling even at high sea state.

NAFO

SHALDAG MKIILength, overall 24.80mBeam, moulded 6.00mDraft, max. 1.15mSpeed, max. 45 knotsDisplacement 58 tonsCrew 8 - 10Range @ 33kn 650nmEndurance (days) 4

SHALDAG MK III/IVLength, overall 26.70mBeam, moulded 6.00mDraft, max. 1.20mSpeed, max. 43+ knotsDisplacement 64 tonsCrew 10 - 12Range @ 33kn 700nmEndurance (days) 4

SHALDAG MK VLength, overall 31.20mBeam, moulded 6.40mDraft, max. 1.25mSpeed, max. 40+ knotsDisplacement 95 tonsCrew 12 - 14Range @ 33kn 1,000nmEndurance (days) 6

SHIP DATA, PROPULSION,

AND PAYLOAD

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