沉渣泛起，还原一个历史上真实的LAVI

半个月过去了，出了黑牢，发点有含金量的东西，不懂英文的童子应该补习功课了

Israel Aircraft Industries (IAI) Lavi
By Ruud Deurenberg
Introduction
During the fifties and sixties the Tsvah Haganah Le Israel - HeylHa'Avir (Israel Defence Force/Air Force (IDF/AF)) relied on France forits combat aircraft. When, after the Six Day War (5 to 10 June 1967), France did not delivered the 50 Dassault Mirage 5Js Israel had ordered and paid for,Israel decided to develop its own combat aircraft. The first such attemptresulted in the Israel Aircraft Industries (IAI) Kfir (Lion Cub), amulti-role fighter developed from the Mirage 5, of which a total of 212 wereproduced. To replace the Kfir, Israel developed the Lavi (Young Lion).
Development
Israel has been embroiled in more wars in recent times than any other nation,with the result that Israeli pilots are very combat experienced, and mostlikely to know exactly what they want in a fighter, within the constrains ofaffordability. When, in 1979, the Lavi program was announced, a great dealof interest was aroused for these reasons.
The Lavi program was launched in February 1980 as a multi-role combataircraft. The Lavi was intended primarily for the close air support (CAS)and battlefield air interdiction (BAI) mission with a secondary air-defensemission. The two-seat version could be used as a conversion trainer. Asoriginally conceived, the Lavi was to have been a light attack aircraft toreplace the elderly McDonnell Douglas A-4 Skyhawk, the McDonnell Douglas F-4Phantom II and the IAI Kfir, remaining in service with the IDF/AF. Asingle-seater, powered by a General Electric F404 turbofan, it was soonperceived that this solution gave no margin for future growth, and analternative engine was chosen, the much more powerful Pratt & Whitney PW1120.With the extra power came demands for greater capability, until the Lavibegan to rival the F-16, which was already in service with the IDF/AF.
The full-scale development (FSD) phase of the Lavi began in October 1982.Originally, the maximum take-off weight was projected as 17,000 kg, butstudies showed that with only a few design changes, and thus a slightincrease in weight, the Lavi could carry more armament. The prize was triedto kept at the same level. With a prospective IDF/AF requirement for up to300 aircraft (including 60 combat-capable two-seaters), the full-scaledevelopment (FSD) phase was to involve five prototypes (B-01 to B-05) ofwhich two, B-01 and B-02, were two-seaters and three, B-03, B-04, and B-05,were single-seaters.
A full-scale mock-up of the Lavi was revealed at the beginning of 1985.
The first Lavi (B-01) flew on 31 December 1986, piloted by IAI chief testpilot Menachem Schmul. The handling was described as excellent, with a highdegree of stability in crosswind landings, and the flight test programproceeded space. The second Lavi (B-02) flew on 30 March 1987. Both LaviB-01 and Lavi B-02 were tandem two-seaters, with the rear cockpit occupiedby test equipment.
Then, on 30 August 1987, the Lavi program was canceled, after Lavi B-01and Lavi B-02 had made more than 80 flights. The two prototypes had flown atspeeds from 204 km/h up to Mach 1.45 at 23o angle of attack. Muchsystems, including the digital flight control, were tested within thisenvelope.
The third Lavi (B-03) and subsequent Lavi prototypes (B-04 and B-05) wouldbe fitted with the definitive wing with increased elevon chord and the lastthree prototypes would also have the complete mission-adaptive avionicssystem. Lavi B-04 and Lavi B-05 were just about to receive the definitivewing when the program was canceled.
The first production aircraft were intended to be delivered in 1990 andinitial operationally capability (IOC) was planned for 1992. At the heightof the production, a total of twelve aircraft would be produced in one month.The Lavi would have been the most important aircraft of the IDF/AF in thenineties.
Stucture
Comparisons with the Lockheed Martin F-16 Fighting Falcon are inevitable, asthe US fighter made a handy yardstick. The Lavi was rather smaller andlighter, with a less powerful powerplant, and the thrust-to-weight ratio wasslightly lower across the board. The configuration adopted was that of atail-less canard delta, although the wing was unusual in having shallow sweepon the trailing edge, giving a fleche planform. The straight leading edge wasswept at 54 degrees, with maneuver flaps on the ourboard sections. The tipswere cropped and fitted with missile rails to carry the Rafael Python 3air-to-air missile. Two piece flaperons occupied most of the trailing edge,which was blended into the fuselage with long fillets. The wing area was38.50 square meters, 38 per cent greater than the wing area of the F-16,giving an almost exactly proportionally lower wing loading, while the aspectratio at 2.10, was barely two-thirds that of the F-16. Pitch control wasprovided by single piece, all-moving canard surfaces, located slightly asternof and below the pilot where they would cause minimal obstruction in vision.Grumman was responsible for the design and development of the wing and thefin, and would produced at least the first 20 wings and fins.
Predictably, relaxed static stability and quadruplex fly-by-wire (FBW), withno mechanical backup was used, linked to nine different control surfaces togive a true control configured vehicle (CCV). In comparison with the F-16,the Lavi is very unstable, with an instability of 10 to 12 per cent. Thesurfaces were programmed to give minimum drag in all flight regimes, whileproviding optimum handling and agility. It was stated that the Lavi had aninherent direct lift control capability, although this was never demonstrated.
The powerplant intake was a plain chin type scoop, similar to that of theF-16, which was known to be satisfactory at high alpha and sideslip angles.The landing gear was lightweight, the nose wheel was located aft of the intakeand retracting rearwards, and the main gear was fuselage mounted, giving arather narrow track. The sharply swept vertical tail, effective at highalpha due to interaction with the vortices shed by the canards, was mountedon a spine on top of the rear fuselage, and supplemented by the two steeplycanted ventral srakes, mounted on the ends of the wing root fillets. Extensiveuse of composites allowed aerolastic tailoring to the wings, so that theoften conflicting demands of shape and rigidity could be resolved to minimizedrag in all flight regimes. Composites were also used in the vertical tail,canards, and various doors and panels. A total of twenty-two per cent of thestructural weight compromise composite materials. IAI claimed a significantreduction in radar cross section (RCS).
Standard practice with high performance jet aircraft is to provide a secondseat for conversion training by shoehorning it in, normally at the expenseof fuel or avionics, or both. IAI adopted a different approach, designing thetwo-seater first, and then adopting it into a single-seater, which leftplenty of room for avionics growth. In fact, the first 30 production aircraftwould all have been two-seaters to aid service entry. Many of these aircraftwere later to have been fitted out for the suppression of enemy air-defense(SEAD) mission.
Powerplant
The powerplant of the Lavi was the Pratt & Whitney PW1120 turbofan, rated at6,137 kg dry and 9,337 kg with reheat and was a derivate of the F100 turbofan.The development of the PW1120, according to IDF/AF specifications, started inJune 1980. It retained the F100 core module, gearbox, fuel pump, forwardducts, as well as the F100 digital electronic control, with only minormodifications. Unique PW1120 components included a wide chord low pressure(LP) compressor, single-stage uncooled low pressure (LP) turbine, simplifiedsingle stream augmentor, and a lightweight convergent/divergent nozzle. Fullscale testing was initiated in June 1982, and flight clearance of the PW1120was tested in August 1984. The PW1120 had 70 per cent similarity with theF100, so the IDF/AF would not need a special facility for spare parts. Itwould be built under licence by Bet-Shemesh Engines Limited in Israel.
IAI installed one PW1120 in the starboard nacelle of an F-4E-32-MC of theIDF/AF (Number 334/66-0327) to explore the airframe/powerplant combinationfor an upgrade program of the F-4E, known as Kurnass 2000 (HeavyHammer) or Super Phantom and to act as an engine testbed for the Lavi. Thepowerplant was more powerful, and more fuel efficient than the GeneralElectric J79-GE-17 turbojet normally installed in the F-4E. The structuralchanges included modifying the air inlet ducts, new powerplant attachmentpoints, new or modified powerplant baydoors, new airframe mounted gearboxwith integrated drive generators and automatic throttle system. It alsoincluded a modified bleed management and air-conditioning ducting system,modified fuel and hydraulic systems, and a powerplant control/airframeinterface. It was first flown on 30 July 1986. Two PW1120 powerplants wereinstalled in the same F-4E and it was flown for the first time on 24 April1987. This proved very successful, allowing the Kurnass 2000 to exceedMach 1 without the afterburners, and endowing a combat thrust-to-weight ratioof 1.04 (17 per cent better than the F-4E). This improved sustained turn rateby 15 per cent, climb rate by 36 per cent, medium-level acceleration by 27per cent and low-level speed with 18 bombs from 1,046 km/h to 1,120 km/h. Itwas demonstrated at the Paris Air Show in 1987 carrying the show number 229and civil registration 4X-JPA. However, McDonnell Douglas refused to approvethe modification, because it offered a flight performance equal to that ofthe F/A-18C/D, and endangered any future sales of the F/A-18C/D.
The internal fuel capacity was 3,330 liters (2,722 kg), some 16 per cent lessthan the F-16, although this was claimed to be offset by the low drag of theLavi airframe and the low specific fuel consumption (sfc) of the powerplant.Single point high pressure refueling was adopted for quick turnaround, andprovision made for air refueling with a female type receptacle compatiblewith flying boom-equipped tankers. To aid the flight test program, the Laviprototypes were also equipped with bolt-on refueling probes. The externalfuel capacity was 4,164 kg in two 2,548 liter drop tanks on the inboardpair wing stations.
Specification of the Pratt & Whitney PW1120
Performance ratings (ISA, S/L):Static thrust: 6,137 kg. Augmented thrust: 9,337 kg. Mass flow: 80.9 kg.    Pressure ratio: 26.8.Specific fuel consumption:Static thrust: 22.7 mg/Ns. Augmentd thrust: 52.65 mg/Ns.Dimensions:Length: 4,110 mm. Maximum diameter: 1,021 mm.Weights:Dry weight: 1,292 kg.Systems
The Lavi had an AiResearch environmental control system for air-conditioningpressurization, and powerplant bleed air control. A pneudralics bootstraptype hydraulic system with a pressure of 207 bars with Adex pumps was alsoinstalled. The electronic system was powered by a Sundstrand 60 kVAintegrated drive generator, for single-channel AC power at 400 Hz, with aSAFT main and Marathon standby battery. Sundstrand also provided theactuation system, with geared rotary actuators, for the leading-edge flaps.The Lavi had an AiResearch emergency power unit (EPU) and a Garrett secondarypower system.
Avionics
The avionics of the Lavi were modular - they could be upgraded by loadingnew software into the Elbit ACE-4 mission computer. The purpose was that theairframe would not require many modifications during its life. The avionicssuite was stated to be almost entirely of Israeli design. The flexibility andthe situational awareness were emphasized to reduce the pilot workload at highg and in a dense threat environment. The air data computer was provided byAstronautics.
The Cockpit
A wrap around windshield and bubble canopy gave excellent all-round vision.But where a steeply raked seat and sidestick controller similar to the F-16might have been excepted, IAI selected a conventional upright seat andcentral control column. The reasoning was as follows. The raked seat raisedthe pilot's knees, causing a reduction in panel space which could ill bespared while neck and shoulder strains were common in the F-16 when a pilotcraned around in his steeply raked seat to search the sky astern whilepulling high g. The sidestick controller was faulted on three counts:
It virtually neutralized the starboard console space.
With a force transducer it was difficult for an instructor pilot to know    precisely what a pupil was trying to do.
In the event of quite a minor injury to the right arm, the pilot would    not be able to recover the Lavi to its base. With a central stick, the    Lavi could be flown left-handed with little difficulty.
The cockpit layout was state of the art, with HOTAS (hands-on-throttle andstick), and a Hughes Aircraft wide-angle diffractive optics head-up-display(HUD) surmounting a single El-Op up-front control panel, through which mostof the systems were operated. Furthermore, the cockpit had LCD technologypowerplant indicators. Elbit Computers Ltd was selected as prime contractorfor the integrated display system, which included the HUD, the three head-downdisplays (HDD) (two of them were color presentations and the third black andwhite), display computers, and communications controller, which included anElta ARC-740 fully computerized onboard UHF radio system. Data-sharing betweenthe HDDs would ensure display redundancy. The navigation system included theTuman TINS 1700 advanced inertial navigation system. Control-column, throttleand display keyboard were all encoded in the display computers, which wouldthemselves had a back-up function to the main aircraft computer, the ElbitACE-4.

Elbit ACE-4 Mission Computer
The Elbit ACE-4 mission computer was selected for the IAI Lavi. It wascompatible with both the MIL-STD-1750A and MIl-STD-1553B standards and couldbe used for display, digital radar, stores management and (future) avionicsintegration. It had a memory of 128 K.
Elta EL/M-2035 Multi-Mode Pulse Doppler Radar
The Elta EL/M-2035 multi-mode pulse-Doppler radar was a development of theElta EL/M-2021B multi-mode Doppler radar of the IAI Kfir-C2. The radar wasvery advanced and had a coherent transmitter and a stable multi-channelreceiver for reliable look-down performance over a broad band of frequenciesand for high resolution mapping. An Elta programmable signal processor,backed by a distributed, embedded computer network, would provide optimumallocation of computing power and great flexibility for growth and theupdating of algorithms and systems growth.
The radar could provide speed and position of targets in the air and on theground, and could provide the pilot with a map of the terrain the Lavi wasoverflying. It could track several targets at 46 km distance in at least fiveair-to-air modes (automatic target acquisition, boresight, look down, look upand track while scan (TWS)). The radar had at least two air-to-ground modes(beam-sharpened ground mapping/terrain avoidance ans sea search). After thecancellation of the Lavi program the radar was offered for multi-rolefighter retrofits, including the Denel Cheetah E.

Elta/Elistra Electronic Warning System
The electronic warning system of the Lavi was designed by Elta and Elistraand was based on an active and passive integrated electronic supportmeasures/electronic countermeasures (ESM/ECM) computer-system, and was capableof rapid threat identification and automatic deception and jamming of enemyradar stations. It was carried internally. This system could also be used inthe future environment of more sophisticated enemy radar systems. The Lavicould eventually carried podded power-managed noise and deception jammers.
Lear Siegler/MBT Fully Digital Flight Control System
The Lear Siegler/MBT fully digital flight control system for the Lavi hadquadruplex redundancy with stability augmentation, and had no mechanicalbackup. It compromised two boxes, with two digital channels built into eachbox. The twin-box configuration hinged on the survivability issue, which wasgiven great emphasis. If one was damaged, the other would provided sufficientcontrol authority to regain base. Each digital channel had associated with itan analogue channel that could have take over its function in the event of afailure. The design total failure rate was not greater than 1 in 107hours. The program was launched in October 1982, and production deliverieswould began in 1988.
Elbit SMS-86 Stores Management System
Elbit was selected during early 1985 to develop the SMS-86 stores managementsystem for the Lavi. The system, which was fully computer-controlled,compromised two units. The stores management processor included oneMIL-STD-1750 computer and two MIL-STD-1553B data-bus interfaces. The armamentinterface unit included a stores interface compatible with the MIL-STD-1750.The SMS-86 was capable of managing both conventional and smart weapons.
Armament
The weapons carriage of the Lavi was mainly semi-conformal, thus reducingdrag, with two hardpoints beneath each wing (the inboard pair was wet for thecarriage of two 2,548 liter auxilliary fuel tanks), plus the wingtip rail andseven underfuselage hardpoints (three tandem pairs plus one on the centreline).The main air-to-air weapon was to be the Rafael Python 3, an Israeli-designedshort range infra-red (IR) homing dogfight air-to-air missile, while a DEFAType 552 (Improved) cannon was housed in the starboard wing root. Theair-to-ground weapons used by the Lavi included the Hughes AGM-65B Maverick,the IAI Gabriel IIIAS, rockets, and the Mk 81, Mk 82, Mk 83, Mk 84, and M117bombs.
DEFA Type 552 (Improved)
The DEFA 552 (Improved) is a single-barrel, five-chamber, revolver type automatic aircraft cannon with a high rate of fire (1,100 to 1,500 roundsper minute (rpm)). It is gas actuated, electrically controlled and fireselectrically initiated 30 mm ammunition. The ammunition is belt fed fromthe left in the Lavi.
The 30 mm DEFA 552 cannon arrived in Israel on the Dassault Mystere IVAfighters and it turned out to be a very effective cannon. Israel MilitaryIndustries (IMI) was able to get the licence rights to manufacture thecannon and it became very popular with the IDF/AF - it was used in theDassault Mirage IIICJ, the IAI Kfir and the McDonnell Douglas A-4 Skyhawk.
In its present form, the modifications and improvements results from itsextensive use in combat by the IDF/AF.
The optional ammunitions for the DEFA Type 552 (Improved) can include:
Hard Core Projectile/Incendiary (AP/I).
High Explosive/Incendiary (HE/I).
Semi Armour Piercing/Incendiary/Tracer (SAP/I/T).
Semi Armour Piercing/High Explosive Incendiary (SAP/HEI).
Target Practice (TP).半个月过去了，出了黑牢，发点有含金量的东西，不懂英文的童子应该补习功课了

Israel Aircraft Industries (IAI) Lavi
By Ruud Deurenberg
Introduction
During the fifties and sixties the Tsvah Haganah Le Israel - HeylHa'Avir (Israel Defence Force/Air Force (IDF/AF)) relied on France forits combat aircraft. When, after the Six Day War (5 to 10 June 1967), France did not delivered the 50 Dassault Mirage 5Js Israel had ordered and paid for,Israel decided to develop its own combat aircraft. The first such attemptresulted in the Israel Aircraft Industries (IAI) Kfir (Lion Cub), amulti-role fighter developed from the Mirage 5, of which a total of 212 wereproduced. To replace the Kfir, Israel developed the Lavi (Young Lion).
Development
Israel has been embroiled in more wars in recent times than any other nation,with the result that Israeli pilots are very combat experienced, and mostlikely to know exactly what they want in a fighter, within the constrains ofaffordability. When, in 1979, the Lavi program was announced, a great dealof interest was aroused for these reasons.
The Lavi program was launched in February 1980 as a multi-role combataircraft. The Lavi was intended primarily for the close air support (CAS)and battlefield air interdiction (BAI) mission with a secondary air-defensemission. The two-seat version could be used as a conversion trainer. Asoriginally conceived, the Lavi was to have been a light attack aircraft toreplace the elderly McDonnell Douglas A-4 Skyhawk, the McDonnell Douglas F-4Phantom II and the IAI Kfir, remaining in service with the IDF/AF. Asingle-seater, powered by a General Electric F404 turbofan, it was soonperceived that this solution gave no margin for future growth, and analternative engine was chosen, the much more powerful Pratt & Whitney PW1120.With the extra power came demands for greater capability, until the Lavibegan to rival the F-16, which was already in service with the IDF/AF.
The full-scale development (FSD) phase of the Lavi began in October 1982.Originally, the maximum take-off weight was projected as 17,000 kg, butstudies showed that with only a few design changes, and thus a slightincrease in weight, the Lavi could carry more armament. The prize was triedto kept at the same level. With a prospective IDF/AF requirement for up to300 aircraft (including 60 combat-capable two-seaters), the full-scaledevelopment (FSD) phase was to involve five prototypes (B-01 to B-05) ofwhich two, B-01 and B-02, were two-seaters and three, B-03, B-04, and B-05,were single-seaters.
A full-scale mock-up of the Lavi was revealed at the beginning of 1985.
The first Lavi (B-01) flew on 31 December 1986, piloted by IAI chief testpilot Menachem Schmul. The handling was described as excellent, with a highdegree of stability in crosswind landings, and the flight test programproceeded space. The second Lavi (B-02) flew on 30 March 1987. Both LaviB-01 and Lavi B-02 were tandem two-seaters, with the rear cockpit occupiedby test equipment.
Then, on 30 August 1987, the Lavi program was canceled, after Lavi B-01and Lavi B-02 had made more than 80 flights. The two prototypes had flown atspeeds from 204 km/h up to Mach 1.45 at 23o angle of attack. Muchsystems, including the digital flight control, were tested within thisenvelope.
The third Lavi (B-03) and subsequent Lavi prototypes (B-04 and B-05) wouldbe fitted with the definitive wing with increased elevon chord and the lastthree prototypes would also have the complete mission-adaptive avionicssystem. Lavi B-04 and Lavi B-05 were just about to receive the definitivewing when the program was canceled.
The first production aircraft were intended to be delivered in 1990 andinitial operationally capability (IOC) was planned for 1992. At the heightof the production, a total of twelve aircraft would be produced in one month.The Lavi would have been the most important aircraft of the IDF/AF in thenineties.
Stucture
Comparisons with the Lockheed Martin F-16 Fighting Falcon are inevitable, asthe US fighter made a handy yardstick. The Lavi was rather smaller andlighter, with a less powerful powerplant, and the thrust-to-weight ratio wasslightly lower across the board. The configuration adopted was that of atail-less canard delta, although the wing was unusual in having shallow sweepon the trailing edge, giving a fleche planform. The straight leading edge wasswept at 54 degrees, with maneuver flaps on the ourboard sections. The tipswere cropped and fitted with missile rails to carry the Rafael Python 3air-to-air missile. Two piece flaperons occupied most of the trailing edge,which was blended into the fuselage with long fillets. The wing area was38.50 square meters, 38 per cent greater than the wing area of the F-16,giving an almost exactly proportionally lower wing loading, while the aspectratio at 2.10, was barely two-thirds that of the F-16. Pitch control wasprovided by single piece, all-moving canard surfaces, located slightly asternof and below the pilot where they would cause minimal obstruction in vision.Grumman was responsible for the design and development of the wing and thefin, and would produced at least the first 20 wings and fins.
Predictably, relaxed static stability and quadruplex fly-by-wire (FBW), withno mechanical backup was used, linked to nine different control surfaces togive a true control configured vehicle (CCV). In comparison with the F-16,the Lavi is very unstable, with an instability of 10 to 12 per cent. Thesurfaces were programmed to give minimum drag in all flight regimes, whileproviding optimum handling and agility. It was stated that the Lavi had aninherent direct lift control capability, although this was never demonstrated.
The powerplant intake was a plain chin type scoop, similar to that of theF-16, which was known to be satisfactory at high alpha and sideslip angles.The landing gear was lightweight, the nose wheel was located aft of the intakeand retracting rearwards, and the main gear was fuselage mounted, giving arather narrow track. The sharply swept vertical tail, effective at highalpha due to interaction with the vortices shed by the canards, was mountedon a spine on top of the rear fuselage, and supplemented by the two steeplycanted ventral srakes, mounted on the ends of the wing root fillets. Extensiveuse of composites allowed aerolastic tailoring to the wings, so that theoften conflicting demands of shape and rigidity could be resolved to minimizedrag in all flight regimes. Composites were also used in the vertical tail,canards, and various doors and panels. A total of twenty-two per cent of thestructural weight compromise composite materials. IAI claimed a significantreduction in radar cross section (RCS).
Standard practice with high performance jet aircraft is to provide a secondseat for conversion training by shoehorning it in, normally at the expenseof fuel or avionics, or both. IAI adopted a different approach, designing thetwo-seater first, and then adopting it into a single-seater, which leftplenty of room for avionics growth. In fact, the first 30 production aircraftwould all have been two-seaters to aid service entry. Many of these aircraftwere later to have been fitted out for the suppression of enemy air-defense(SEAD) mission.
Powerplant
The powerplant of the Lavi was the Pratt & Whitney PW1120 turbofan, rated at6,137 kg dry and 9,337 kg with reheat and was a derivate of the F100 turbofan.The development of the PW1120, according to IDF/AF specifications, started inJune 1980. It retained the F100 core module, gearbox, fuel pump, forwardducts, as well as the F100 digital electronic control, with only minormodifications. Unique PW1120 components included a wide chord low pressure(LP) compressor, single-stage uncooled low pressure (LP) turbine, simplifiedsingle stream augmentor, and a lightweight convergent/divergent nozzle. Fullscale testing was initiated in June 1982, and flight clearance of the PW1120was tested in August 1984. The PW1120 had 70 per cent similarity with theF100, so the IDF/AF would not need a special facility for spare parts. Itwould be built under licence by Bet-Shemesh Engines Limited in Israel.
IAI installed one PW1120 in the starboard nacelle of an F-4E-32-MC of theIDF/AF (Number 334/66-0327) to explore the airframe/powerplant combinationfor an upgrade program of the F-4E, known as Kurnass 2000 (HeavyHammer) or Super Phantom and to act as an engine testbed for the Lavi. Thepowerplant was more powerful, and more fuel efficient than the GeneralElectric J79-GE-17 turbojet normally installed in the F-4E. The structuralchanges included modifying the air inlet ducts, new powerplant attachmentpoints, new or modified powerplant baydoors, new airframe mounted gearboxwith integrated drive generators and automatic throttle system. It alsoincluded a modified bleed management and air-conditioning ducting system,modified fuel and hydraulic systems, and a powerplant control/airframeinterface. It was first flown on 30 July 1986. Two PW1120 powerplants wereinstalled in the same F-4E and it was flown for the first time on 24 April1987. This proved very successful, allowing the Kurnass 2000 to exceedMach 1 without the afterburners, and endowing a combat thrust-to-weight ratioof 1.04 (17 per cent better than the F-4E). This improved sustained turn rateby 15 per cent, climb rate by 36 per cent, medium-level acceleration by 27per cent and low-level speed with 18 bombs from 1,046 km/h to 1,120 km/h. Itwas demonstrated at the Paris Air Show in 1987 carrying the show number 229and civil registration 4X-JPA. However, McDonnell Douglas refused to approvethe modification, because it offered a flight performance equal to that ofthe F/A-18C/D, and endangered any future sales of the F/A-18C/D.
The internal fuel capacity was 3,330 liters (2,722 kg), some 16 per cent lessthan the F-16, although this was claimed to be offset by the low drag of theLavi airframe and the low specific fuel consumption (sfc) of the powerplant.Single point high pressure refueling was adopted for quick turnaround, andprovision made for air refueling with a female type receptacle compatiblewith flying boom-equipped tankers. To aid the flight test program, the Laviprototypes were also equipped with bolt-on refueling probes. The externalfuel capacity was 4,164 kg in two 2,548 liter drop tanks on the inboardpair wing stations.
Specification of the Pratt & Whitney PW1120
Performance ratings (ISA, S/L):Static thrust: 6,137 kg. Augmented thrust: 9,337 kg. Mass flow: 80.9 kg.    Pressure ratio: 26.8.Specific fuel consumption:Static thrust: 22.7 mg/Ns. Augmentd thrust: 52.65 mg/Ns.Dimensions:Length: 4,110 mm. Maximum diameter: 1,021 mm.Weights:Dry weight: 1,292 kg.Systems
The Lavi had an AiResearch environmental control system for air-conditioningpressurization, and powerplant bleed air control. A pneudralics bootstraptype hydraulic system with a pressure of 207 bars with Adex pumps was alsoinstalled. The electronic system was powered by a Sundstrand 60 kVAintegrated drive generator, for single-channel AC power at 400 Hz, with aSAFT main and Marathon standby battery. Sundstrand also provided theactuation system, with geared rotary actuators, for the leading-edge flaps.The Lavi had an AiResearch emergency power unit (EPU) and a Garrett secondarypower system.
Avionics
The avionics of the Lavi were modular - they could be upgraded by loadingnew software into the Elbit ACE-4 mission computer. The purpose was that theairframe would not require many modifications during its life. The avionicssuite was stated to be almost entirely of Israeli design. The flexibility andthe situational awareness were emphasized to reduce the pilot workload at highg and in a dense threat environment. The air data computer was provided byAstronautics.
The Cockpit
A wrap around windshield and bubble canopy gave excellent all-round vision.But where a steeply raked seat and sidestick controller similar to the F-16might have been excepted, IAI selected a conventional upright seat andcentral control column. The reasoning was as follows. The raked seat raisedthe pilot's knees, causing a reduction in panel space which could ill bespared while neck and shoulder strains were common in the F-16 when a pilotcraned around in his steeply raked seat to search the sky astern whilepulling high g. The sidestick controller was faulted on three counts:
It virtually neutralized the starboard console space.
With a force transducer it was difficult for an instructor pilot to know    precisely what a pupil was trying to do.
In the event of quite a minor injury to the right arm, the pilot would    not be able to recover the Lavi to its base. With a central stick, the    Lavi could be flown left-handed with little difficulty.
The cockpit layout was state of the art, with HOTAS (hands-on-throttle andstick), and a Hughes Aircraft wide-angle diffractive optics head-up-display(HUD) surmounting a single El-Op up-front control panel, through which mostof the systems were operated. Furthermore, the cockpit had LCD technologypowerplant indicators. Elbit Computers Ltd was selected as prime contractorfor the integrated display system, which included the HUD, the three head-downdisplays (HDD) (two of them were color presentations and the third black andwhite), display computers, and communications controller, which included anElta ARC-740 fully computerized onboard UHF radio system. Data-sharing betweenthe HDDs would ensure display redundancy. The navigation system included theTuman TINS 1700 advanced inertial navigation system. Control-column, throttleand display keyboard were all encoded in the display computers, which wouldthemselves had a back-up function to the main aircraft computer, the ElbitACE-4.

Elbit ACE-4 Mission Computer
The Elbit ACE-4 mission computer was selected for the IAI Lavi. It wascompatible with both the MIL-STD-1750A and MIl-STD-1553B standards and couldbe used for display, digital radar, stores management and (future) avionicsintegration. It had a memory of 128 K.
Elta EL/M-2035 Multi-Mode Pulse Doppler Radar
The Elta EL/M-2035 multi-mode pulse-Doppler radar was a development of theElta EL/M-2021B multi-mode Doppler radar of the IAI Kfir-C2. The radar wasvery advanced and had a coherent transmitter and a stable multi-channelreceiver for reliable look-down performance over a broad band of frequenciesand for high resolution mapping. An Elta programmable signal processor,backed by a distributed, embedded computer network, would provide optimumallocation of computing power and great flexibility for growth and theupdating of algorithms and systems growth.
The radar could provide speed and position of targets in the air and on theground, and could provide the pilot with a map of the terrain the Lavi wasoverflying. It could track several targets at 46 km distance in at least fiveair-to-air modes (automatic target acquisition, boresight, look down, look upand track while scan (TWS)). The radar had at least two air-to-ground modes(beam-sharpened ground mapping/terrain avoidance ans sea search). After thecancellation of the Lavi program the radar was offered for multi-rolefighter retrofits, including the Denel Cheetah E.

Elta/Elistra Electronic Warning System
The electronic warning system of the Lavi was designed by Elta and Elistraand was based on an active and passive integrated electronic supportmeasures/electronic countermeasures (ESM/ECM) computer-system, and was capableof rapid threat identification and automatic deception and jamming of enemyradar stations. It was carried internally. This system could also be used inthe future environment of more sophisticated enemy radar systems. The Lavicould eventually carried podded power-managed noise and deception jammers.
Lear Siegler/MBT Fully Digital Flight Control System
The Lear Siegler/MBT fully digital flight control system for the Lavi hadquadruplex redundancy with stability augmentation, and had no mechanicalbackup. It compromised two boxes, with two digital channels built into eachbox. The twin-box configuration hinged on the survivability issue, which wasgiven great emphasis. If one was damaged, the other would provided sufficientcontrol authority to regain base. Each digital channel had associated with itan analogue channel that could have take over its function in the event of afailure. The design total failure rate was not greater than 1 in 107hours. The program was launched in October 1982, and production deliverieswould began in 1988.
Elbit SMS-86 Stores Management System
Elbit was selected during early 1985 to develop the SMS-86 stores managementsystem for the Lavi. The system, which was fully computer-controlled,compromised two units. The stores management processor included oneMIL-STD-1750 computer and two MIL-STD-1553B data-bus interfaces. The armamentinterface unit included a stores interface compatible with the MIL-STD-1750.The SMS-86 was capable of managing both conventional and smart weapons.
Armament
The weapons carriage of the Lavi was mainly semi-conformal, thus reducingdrag, with two hardpoints beneath each wing (the inboard pair was wet for thecarriage of two 2,548 liter auxilliary fuel tanks), plus the wingtip rail andseven underfuselage hardpoints (three tandem pairs plus one on the centreline).The main air-to-air weapon was to be the Rafael Python 3, an Israeli-designedshort range infra-red (IR) homing dogfight air-to-air missile, while a DEFAType 552 (Improved) cannon was housed in the starboard wing root. Theair-to-ground weapons used by the Lavi included the Hughes AGM-65B Maverick,the IAI Gabriel IIIAS, rockets, and the Mk 81, Mk 82, Mk 83, Mk 84, and M117bombs.
DEFA Type 552 (Improved)
The DEFA 552 (Improved) is a single-barrel, five-chamber, revolver type automatic aircraft cannon with a high rate of fire (1,100 to 1,500 roundsper minute (rpm)). It is gas actuated, electrically controlled and fireselectrically initiated 30 mm ammunition. The ammunition is belt fed fromthe left in the Lavi.
The 30 mm DEFA 552 cannon arrived in Israel on the Dassault Mystere IVAfighters and it turned out to be a very effective cannon. Israel MilitaryIndustries (IMI) was able to get the licence rights to manufacture thecannon and it became very popular with the IDF/AF - it was used in theDassault Mirage IIICJ, the IAI Kfir and the McDonnell Douglas A-4 Skyhawk.
In its present form, the modifications and improvements results from itsextensive use in combat by the IDF/AF.
The optional ammunitions for the DEFA Type 552 (Improved) can include:
Hard Core Projectile/Incendiary (AP/I).
High Explosive/Incendiary (HE/I).
Semi Armour Piercing/Incendiary/Tracer (SAP/I/T).
Semi Armour Piercing/High Explosive Incendiary (SAP/HEI).
Target Practice (TP).