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Sunday, October 29, 2006

Northrop/McDonnell Douglas YF-23 Black Widow II

The Northrop/McDonnell Douglas YF-23 Black Widow II was a prototype fighter aircraft designed for the United States Air Force. It was passed over in favor of the YF-22 that has entered production as the F-22 Raptor.

The YF-22 and YF-23 were competing in the USAF's Advanced Tactical Fighter program. Conceived in the early 1980s, to specify a replacement for the F-15 Eagle, contracts for the two most promising designs were awarded in 1986, with the YF-23 delivered in 1989 and the evaluation concluded in 1991.
The YF-23 was designed with stealth as a high priority and was a highly unconventional-looking aircraft with diamond-shaped wings and a V-tail. The YF-23A met USAF requirements for survivability, supersonic cruise, stealth, and ease of maintenance. However, the YF-22A was more maneuverable than the YF-23A and won the competition in April 1991.

Although the precise results of the evaluation are not yet public knowledge, it is often claimed that the YF-23 was faster and stealthier than its competitor, but the USAF chose the YF-22 due to ease of production, maintenance, and potential for future development, as well as its relatively lower production cost. On the other hand, some say that the YF-22 was chosen for its superior subsonic maneuverability due to thrust vectoring. Others point out the YF-23's comparatively flawed weapons release mechanism wherein missiles are stacked on racks, and a weapons jam of a lower-positioned missile could prevent the firing of the missile above it.

Two aircraft were built. After losing the competition, both YF-23 prototypes were transferred from Northrop to NASA's Dryden Flight Center, at Edwards AFB, California.
Aircraft PAV-2 is now an exhibit at the Western Museum of Flight in Hawthorne, California and PAV-1 was recently moved to the National Museum of the United States Air Force, where it sits along side the Boeing X-32 in one of the Museum's restoration hangars awaiting restoration for display.

In late 2004, Northrop Grumman proposed a YF-23 based design for the USAF's interim bomber requirement, a role for which the FB-22 and B-1R are also competing. The interim bomber requirement has since been cancelled in favor of a more long-term, permament bomber replacement requirement; however, the same YF-23-derived design will likely be adapted to fulfill this role as well.

Specifications

Length: 67 ft 5 in (20.60 m)
Wingspan: 43 ft 7 in (13.30 m)
Height: 13 ft 11 in (4.30 m)
Wing area: 948 ft² (88m²)
Empty weight: 32,934 lb (14,970 kg)
Loaded weight: 51,320 lb (23,327 kg)
Max takeoff weight: 64,000 lb (29,029 kg)

Powerplant:

2× General Electric YF120 or Pratt & Whitney YF119 turbofan, 35,000 lbf (277 kN)

Performance:
Maximum speed: 1,400 mph (2,240 km/h)
Combat radius: 921 miles (1,474 km)
Service ceiling: 65,000 ft (19,800 m)
Wing loading: 54 lb/ft² (265 kg/m²)
Thrust/weight: 1.4

Armament:
1× 20 mm M61 Vulcan cannon
6× air-to-air missiles, including the AIM-120 AMRAAM and AIM-9 Sidewinder


Links:
www.fas.org
www.voodoo.cz
www.globalaircraft.org
www.dreamlandresort.com

(Adapted from http://www.wikipedia.org/ )

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BAC TSR-2

The British Aircraft Corporation's TSR-2 was an ill-fated Cold War project in the early 1960s to create what would, at that time, have been one of the most advanced aircraft in the world.

In the 1950s, the British Royal Air Force was aware that the Canberra bomber would need to be replaced, and a specification for its replacement with additional strike and reconnaissance roles was drafted in the form of GOR (General Operational Requirement) 339 in 1956. This specification was exceptionally ambitious for the technology of the day, requiring a supersonic all-weather aircraft that could deliver nuclear weapons over a long range, operate at high level (at Mach 2+) or low level (at Mach 1.2), with a short takeoff ability from rough and ready airstrips.

The envisioned "standard mission" for the TSR-2 was to carry a 2,000 lb (900 kg) weapon internally for a combat radius of 1,000 nautical miles (nm) (1,852 km). Of that mission 100 nm (185 km) was to be flown at higher altitudes at Mach 1.7 and the 200 nm (370 km) into and out of the target area was to be flown as low as 200 feet (60 m) at Mach 0.95. The rest of the mission was to be flown at Mach 0.92. If the entire mission were to be flown at the low 200-foot altitude, the mission radius was reduced to 700 nm (1300 km). Heavier weapons loads could be carried with further reductions in range.
The design was a large aircraft with large shoulder mounted slab-wing with down-turned tips, all-moving swept tailplane, a large all-moving fin. powered by two Bristol-Siddeley Olympus afterburning turbojets. The latter were a variant of those used in the Avro Vulcan and Concorde.

The design featured blown flaps to achieve the short take off and landing requirement, something which later designs would achieve with the technically more complex swing-wing approach. The aircraft featured some extremely sophisticated avionics for navigation and mission delivery which was also to be one of the reasons for the spiralling costs of the project. Some features, such as ground-following terrain radar, FLIR cameras, side-looking airborne radar and the sophisticated autopilot did only become commonplace on military aircraft later. The wing loading was high for its time, and this gave the aircraft the ability to fly at very high speed and low level with great stability without being constantly upset by thermals and other ground-related weather phenomena. This in turn made the innovative ground-following radar and autopilot system feasible.

Despite the rocketing costs, two prototype aircraft were completed. In testing the TSR-2 was found to easily meet the demanding performance specification. Aerodynamically the aircraft was trouble-free, but there were continual problems with the engines and the undercarriage. Initial flight tests were all performed with the undercarriage down and engine power strictly limited.

The first supersonic test flight, the fourteenth overall, had to be performed with only one afterburner due to problems with one of the engines. A speed of Mach 1.2 was reached on that occasion.
The American team behind the General Dynamics F-111 project had been pressing their case and newspaper reports had suggested that the RAF were considering it. In the next year budget speech , the cancellation in favour of the F-111 was announced.
Instead of the TSR-2, the RAF decided it would buy the swing-wing American General Dynamics F-111 - however, the F-111 itself suffered such enormous cost escalation (exceeding that of the TSR-2 projection ) that the RAF eventually cancelled their order, procuring instead the F-4 Phantom II and the Blackburn Buccaneer.

Estimated Specifications

Dimensions:
Length: 89 ft ½ in (27.12 m)
Wingspan: 37 ft 1¾ in (11.27 m)
Height: 23 ft 9 in (7.24 m)
Wing area: 702.9 ft² (65.3 m²)

Weights:
Empty 54,750 lb (24,834 kg)
Loaded 79,573 lb lb (36,169 kg)
Maximum takeoff 102,200 lb (46,357 kg)

Powerplant:
Engines 2× Bristol-Siddeley Olympus B.O1.22R
Thrust 2× 30,610 lbf (2× 136.7 kN)

Performance:
Maximum speed: Mach 2.15
Combat range: 1150 miles (1850 km)
Ferry range: 4256 miles (6850 km)
Service ceiling: 54,000 ft (16,459 m)
Rate of climb: 50,000 ft/min (16,000 m/min)

Armament:
Payload Internal weapons bay, 20 ft (6 m) with 1 nuclear or 6 x 1000 lb (450 kg) HE, or 4 x 37 rocket packs or nuclears on inner pylons only.


Links:
www.thunder-and-lightnings.co.uk
www.historyofwar.org
www.unrealaircraft.com

(Adapted from http://www.wikipedia.org/ )

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IAI Kfir

Israel Aircraft Industries Kfir is an Israeli-built all-weather, multi-role combat aircraft based on a modified Dassault Mirage 5 airframe, with Israeli avionics and an Israeli-made version of the General Electric J79 turbojet engine.The IAI Kfir is one of the best known examples of the developmental approach to the design and construction of combat aircraft, which consists in the modernization of well-proven airframes to face the challenges posed by an increasingly sophisticated air-combat environment.The project that would ultimately give birth to the Kfir can be traced back to Israel's need for adapting the Dassault Mirage IIIC to the specific requirements of the Israeli Air Force (IAF).

While the Mirage IIICJ proved to be extremely effective in the air-superiority role, its relatively short range of action imposed some drawbacks to its usefulness as a ground-attack aircraft.
Thus, in the mid-1960s, at the request of Israel, Dassault Aviation began developing the Mirage 5, a fair-weather, ground-attack version of the Mirage III. By 1968, Dassault had finished production of the 50 Mirage 5Js paid for by Israel, but an arms embargo imposed upon this country by the French government in 1967 prevented Dassault from ever delivering the aircraft. The Israelis replied by producing an unlicensed copy of the Mirage 5, the Nesher (Eagle), with technical specifications for both the airframe and the engine obtained by the Israeli intelligence.

In order to accommodate the General Electric J79 powerplant on the Mirage III's airframe, and to deliver the added cooling required by the J79, the aircraft's rear fuselage was slightly shortened and widened, its air intakes were enlarged, and a large air inlet was installed at the base of the fin, so as to supply the extra cooling needed for the afterburner. The engine itself was encased in a titanium heatshield.
When the Kfirs were modified to use small detachable canards and other minor improvements, they were given the name Kfir C.1.

The much improved Kfir C.2, revealed in 1976, was the first full-standard version of the aircraft. Benefiting from the operational experience obtained with the first variant, the C.2 featured delta canard foreplanes mounted on the air intakes, narrow "strakes" along the tip of the nose, and extended "dogtooth" outer wing panels. These aerodynamic modifications gave the Kfir better all-around manoeuvrability, reduced landing and take-off distance, and superior handling at low speeds. All C.2s were also equipped with a Martin-Baker Mk.10 ejection seat, and seven weapons pylons.
In 1983, IAI began to upgrade the Kfir C.2s/TC.2s to a new variant, the Kfir C.7/TC.7, which carried a modified version of the J79-GE-17E powerplant, with an additional 4.45 kN (1,000 lb st) of afterburning thrust, and an enhanced thrust-to-weight ratio. The Kfir C.7 featured a modernized HOTAS cockpit, with new avionics, including the Elta EL/M-2021B pulse-Doppler radar and the Elta EL/L-8202 advanced electronic jammer, plus guided weapons carrying capability, two additional hardpoints below the intake ducts (for a total of nine), and provision for in-flight refueling. With a maximum take-off weight increased by 1,540 kg (3,395 lb), as well as an improved combat radius, the Kfir C.7 was a much better ground attack aircraft than its predecessor. The emphasis given on the improvement of the strike capabilities of the Kfir signaled the new role assigned to the aircraft in the IAF's order or battle during the 1980s, as the F-15s and F-16s took over the air-superiority and interception missions.

Since the J79 turbojet engine as well as much of the technology inside the Kfir are produced in Israel under U.S. license, all export sales of the Kfir are subject to prior approval from the U.S. State Department, a fact that has limited the sale of the Kfir to foreign nations.
As of 2006, the IAI Kfir has been exported to Colombia, Ecuador, and Sri Lanka. Also, 25 Kfir C.1s were leased to the US Navy and the USMC in the 1980s.

Specifications (Kfir C.2)

Length: 15.65 m (51 ft 4.25 in)
Wingspan: 8.21 m (26 ft 11.5 in)
Height: 4.55 m (14 ft 11.5 in)
Wing area: 34.80 m² (374.60 sq ft)
Empty weight: 7,285 kg (16,060 lb)
Loaded weight: 10,415 kg (22,961 lb)
Max takeoff weight: 14,670 kg (32,340 lb)

Powerplant:
1× IAl Bedek-built General Electric J-79-J1E turbojet
Dry thrust: 52.89 kN (11,890 lb st)
Thrust with afterburner: 83.40 kN (18,750 lb st)

Performance:
Maximum speed: 2,440 km/h (1,516 mph)
Range: 770 km (480 mi)
Service ceiling: 17,700 m (58,000 ft)
Rate of climb: 233.3 m/s (45,930 ft/min)

Armament:
Guns: 2x Rafael-built DEFA 553 30-mm cannons with 140 rounds per gun.
Maximum Ordnance Load: 6,065 kg (13,343 lb)
Bombs: Mk-82, GBU-13 LGB, TAL-1 and TAL-2 CBUs, BLU-107 Durandal, HOBOS.
Unguided rocket launchers
Missiles: Shrike ARMs; Maverick ASMs; Sidewinder, Shafrir, and Python-series AAMs.

Links:
www.israeli-weapons.com
www.globalaircraft.org
www.fas.org
www.acig.org


(Adapted from http://www.wikipedia.org/ )

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Friday, October 06, 2006

Chengdu J-10

The Chengdu J-10 is a multirole fighter aircraft designed in collaboration with Israel Aircraft Industries and produced by the People's Republic of China Chengdu Aircraft Industry Corporation” (CAC).
The program was conceived in the early 1980s, to counter new fourth generation fighters then being introduced by the USSR (namely, the MiG-29 and Su-27)

Initially designed as a specialized counter-air fighter, it was later remade into a multirole aircraft capable of both anti-air combat and ground attack missions. It has been argued that the J-10 is based on the now cancelled Israeli Lavi.
Having been designed under much secrecy, many details of the J-10 remain unknown and are subject to much speculation. The first flight of the J-10 took place sometime in 1996, but the program suffered a major delay due to a fatal accident which occurred in 1997. This incident was thought to be the result of errors in the J-10’s fly-by-wire system. (Note, there is evidence, albeit non-conclusive, that only one prototype was flying; the other was a ground static testbed. Hence, no crash occurred.) A redesigned prototype flew in 1998, resuming flight testing of the aircraft. Service entry into the PLAAF occurred in late 2005.

The J-10 is a single-seat, delta winged aircraft powered by a single, Russian-designed AL-31FN turbofan (maximum static power output of 12,500 kgf (123 kN, 27,600 lbf)). The airframe possesses a large vertical tail, as well as canards placed near the cockpit. The air intake is rectangular in shape, and is located beneath the fuselage. Construction likely incorporates much use of composite materials, as well as more conventional metals. Performance is generally speculated to be within the class of a late-model F-16, although maneuverability is thought to be superior (possibly within the range of some early fifth generation Western fighters). A bubble canopy provides 360 degrees of visual coverage for the pilot.
It was reported in November 2005 that a first batch of AL-31FN thrust vectoring engines had already been received from Russia for use in J-10s. A second batch was supposed to arrive later that year, and the rest would arrive by mid-2006. On 9 January 2006, it was claimed that these new engines were actually termed AL-31FN M1, and would be used in a new advanced version of the J-10 called the "Super-10". Regardless of how they are eventually used, thrust vectoring will boost the J-10's maneuverability.
China has made progress toward development of it own WS-10A 'Taihang' turbofan engine. There are plans to produce future variants of J-10 and J-11 using WS-10A engine.

A digital, quadruplex fly-by-wire system aids the pilot in flying the aircraft. Information is provided visually to the pilot, in the form of three liquid crystal Multi-Functional Displays within the cockpit. Western-style HOTAS (Hands On Throttle And Stick) controls are incorporated in the J-10's design.
The radar type equipping the J-10 is not yet known; possible candidates include the Russian RP-35, the Israeli EL/M-2035, the Italian Grifo 2000 and the domestic JL-10A. A comprehensive ECM (Electronic countermeasures) package is likely to be present, including active jammers.

It was reported by Jane's Defence Weekly on 9 January 2006, that a more advanced version of the J-10 is planned, "referred to as the Super-10, with a more powerful engine, thrust-vector control, stronger airframe and passive phased-array radar"
So far the J-10 has been offered only to Pakistan for export as the F-10.
On April 12, 2006 the Pakistani cabinet approved the purchase of at least 36 J-10s under the designation FC-10.
The wings provide 11 hardpoints for the attachment of up to 4,500 kg (9,900 lb) of weaponry, fuel tanks, and ECM equipment. Built-in armament consists of a 23 mm cannon, located within the fuselage. External weaponry may include: short-range infrared air-to-air missiles (Chinese PL-8, or the Russian R-73), medium-range radar-guided air-to-air missiles (Chinese PL-11 and PL-12, or the Russian R-77), laser-guided and un-guided bombs, anti-ship missiles (Chinese YJ-9K), and anti-radiation missiles (YJ-9).

Estimated Specifications

Length: 14.57 m (47 ft 10 in)
Wingspan: 8.78 m (28 ft 9 in)
Height: 4.80 m (15 ft 9 in)
Wing area: 33 m² (360 ft²)
Empty weight: 9,750 kg (21,500 lb[4])
Max takeoff weight: 18,400 kg (40,600 lb)


Powerplant:

1× Lyulka-Saturn AL-31FN turbofan
Dry thrust: 79.43 kN (17,860 lbf)
Thrust with afterburner: 123 kN (27,600 lbf)

Performance:
Maximum speed: Mach 2.0 (2,450 km/h, 1,520 mph) at altitude
g-Limits: +9/-3 g (+88/-29 m/s², +290/-97 ft/s²
Combat radius: 550 km (300 nm, 340 mi)
Maximum range: 1,850 km (1,000 nm, 1,150 mi)
Service ceiling: 18,000 m (59,000 ft)
Minimum thrust/weight With afterburner: 0.68

Armament:
Guns: 1× 23 mm internal cannon
Hardpoints: 11, 3 under each wing and 5 under the fuselage
Missiles:
Air-to-air: PL-8, PL-11, PL-12, R-73, R-77
Air-to-surface: YJ-9, YJ-9K
Bombs: laser-guided bombs, unguided bombs


Links:
www.aeronautics.ru
www.milavia.net
www.globalsecurity.org
www.sinodefence.com (Adapted from http://www.wikipedia.org/ )

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Beriev Be-200

The BERIEV BE-200 is a multipurpose amphibious aircraft being developed by the Beriev Aircraft Company as part of acooperative project with the Science and Production Corporation "Irkut".

Design Bureau "Progress" and joint stock company "Motor Sich" in Zaporozhiye designed and manufactured a specific "maritime" corrosion-resistant version of the D-436 engine specially for the Be-200 amphibian.
The basic Be-200 version is used for aerial firefighting. Beriev also offers models with a pressurised fuselage, including transport (Be-210), passenger, patrol and other special versions. There is an anti-submarine warfare version equipped with the "Morskoy Zmey" (Sea Dragon) search and targeting system.
The Be-200 first flew on September 24, 1998 from the airfield of the Irkutsk Aviation and Production Association. The amphibian took off from the water on September 10, 1999 in Taganrog.
The first prototype aircraft has successfully completed 650 flight hours and carries Russian certification as a fire fighting aircraft. Seven aircraft are on order for the launch customer, TsENTROSPAS/MChS or the Russian Ministry of Emergency Situations. Three have been delivered, the first in June 2003.

The Russian Ministry of Emergency Situations (MChS) was the first customer for the Be-200 and placed an order for seven Be-200ChS versions of the place to perform fire extinguishing operations, search and rescue, air ambulance, and cargo operations. The second Be-200 took off from the runway of the Irkutsk Aviation and Production Company airfield on August 27, 2002. It was built in the Be-200ChS version with an equipment set meeting the requirements of the Ministry of Emergency Situations.
The Be-200ChS is manufactured in Irkutsk and the first production airplane flew on June 17, 2003. The Ministry of Emergency Situations hope to have the rest delivered by the end of 2005.
Much interest was expressed in meetings with airline representatives for both the firefighting and passenger Be-200 versions.

The Be-200 project has been studied by EADS experts in terms of marketing, economic advantage, with the possibility of acquiring foreign certification with Rolls-Royce Deutschland BR-715 engines.
In a fire-fighting mission, the fully fuelled aircraft can fly 200km from the airfield to a water reservoir, make successive trips between the site of the fire and the reservoir (over a range of 10km from the fire zone to the reservoir), to drop a total of 310,000kg of water on the fire and make the 200km return flight to the airfield for refuelling.
The aircraft is capable of scooping 12t of water in 14 seconds from seas with waves up to 1.2m. The aircraft flies at speeds above a minimum drop speed of 220km/h to empty the water tanks over the site of the fire in 0.8 to 1.0 seconds.

The hull is of single step design with a high length to beam ratio, which contributes to the stability and controllability in water, and at landing and take-off. The hull is constructed of aluminium and lithium alloys. The wings are fitted with underwing stabiliser floats.

In February 2004, Hawkins & Powers, a US company that specialises in fighting forest fires, signed a letter of intent for the sale of eight Be-200 aircraft with Irkut Corporation. The aircraft will be powered by the Rolls-Royce BR715 engines and are to be delivered in 2007.
In August 2004, Irkut leased one aircraft to the Protezione Civile of Italy for firefighting. The aircraft began operations in July 2005, on the island of Sardinia.
In June 2006, the Ministry of Internal Administration of Portugal signed a contract with Irkut for the lease of one Be-200 from July 2006 for firefighting.
Portugal plans to obtain several Be-200 airplane from Russian toward repayment of the former Soviet Union’s debt.


Specifications

Wingspan:31.8 m (104 ft 4 in)
Length: 31.2 m (102 ft 4 in)

Power:

two 7500 kgf (73.5 kN) Progress D-436TP engines (with options of BMW-Rolls-Royce Br-715-53 turbofan or Allison GMA-2100 turbofan)

Maximum speed: 710 km/h (440 mph)
Cruising speed: 600 km/h (370 mph)
Economy speed: 550 km/h (340 mph)
Landing speed: 200 km/h (125 mph)
Takeoff speed: 220 km/h (140 mph)
Loaded weight: (firefighter) 43,000 kg (94,800 lb)
Operational range: 2100 km (1,300 mi)
Dry tank Range: 3850 km (2,400 mi)
Preferred operational altitude: 8000 m (26,250 ft)

Links:
www.airliners.net
www.luftfahrt.net
www.aviationexplorer.com

(Adapted from http://www.wikipedia.org/ )


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IAI Lavi

The IAI Lavi (lion cub in Hebrew) was a multi billion dollar project that was allegedly disbanded under preasure from the US Governmant.
The prototype fighter jet developed was put on display for photographers and was never heard of or spoken about again.

The project began in February 1980, when the Israeli government authorized the IAF to present it with a list of technical specifications for the development of the IAF's future fighter. The development stage began in October 1982, with the choice of a Pratt & Whitney engine already having been made.
One of the Lavi's most distinct advantages is its functional features, especially its cockpit, custom-built entirely using input from active IAF fighter pilots. Drawing on their operational experience, the design was geared to let the pilot handle the tactical aspects of the battle, without having to worry about monitoring and controlling the various subsystems. The avionics of the Lavi were considered to be innovative and groundbreaking, and included self-analysis equipment to make maintenance easier.

On December 31, 1986, the first prototype of the plane took off on its maiden flight. The test pilot, Menachem Shimol, head of IAI's Air Operations section, took off at 13:21 and stayed in the air for 26 minutes, during which he checked the engine and controls.
About three months later, a second prototype took to the air. In its maiden flight, the engine systems, flight control, electrical system, hydraulics and air conditioning were evaluated. The second prototype had some improvements over the first, with a belly-mounted fuel tank, a special midair refuelling pipe and several avionic systems that were not employed in the first prototype.

The IAI had produced three prototypes out of the originally-planned five when the Israeli government decided to cancel the project because of budget problems and bickering among various economic and political pressure groups. The total cost for the development and production of the Lavi was $6.4 billion U.S. in 1983, around 40 percent of which was paid by the U.S. government. The project was canceled in part because the U.S. was not prepared to finance an aircraft that would compete in the export market with the F-16C/D and the F/A-18C/D, and also because a dispute arose as to the final cost. The Israeli government was unable to finance the project alone and canceled it on August 30, 1987. The decision to cancel was approved with a majority of only one vote.

Specifications

General characteristics:
Length: 14.57 m (47 ft 10 in)
Wingspan: 8.78 m (28 ft 10 in)
Height: 4.78 m (15 ft 8 in)
Wing area: 33.0 m² (355 ft²)
Empty weight: 7,031 kg (15,500 lb)
Loaded weight: 9,991 kg (22,025 lb)
Max takeoff weight: 19,277 kg (42,500 lb)

Powerplant:
1× Pratt & Whitney PW1120 afterburning turbofan, 91.5 kN (20,600 lbf)

Performance:
Maximum speed: 1,965 km/h (1,220 mph)
Range: 3,700 km (2,300 mi)
Service ceiling: 15,240 m (50,000 ft)
Rate of climb: 254 m/s (50,000 ft/min)
Thrust/weight: 0.94

Armament:
1x 30 mm DEFA cannon
7,260 kg (16,000 lb)

Links:
www.aerospaceweb.org
aircraftstories.free.fr
www.geocities.com/TimesSquare/Cavern/6130/iafm_lavi.htm
www.combatsim.com

(Adapted from http://www.wikipedia.org/ )

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