<p>The F-16 Fighting Falcon, also called the 'Viper', is the most numerous USAF aircraft. LANTIRN-equipped F-16C block 40/42 fighter-bombers equip the bulk of the active force's fighter wings while F-16C block 50/52s have begun delivery. A series of OCUs (operational capability upgrades) will continue enhancing the performance of Falcons already in service. F-16As and some F-16Cs serve in Air National Guard and Air Force Reserve units, the F-16A ADF (air defense fighter) version equipping ANG squadrons with an interceptor mission.
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<p>The F-16 is distinctive in appearance, with its air intake or shock inlet located directly below the pilot. The fighter's configuration uses wing/body flare to enhance lift at high angles of attack. The wing itself is straight, albeit with leading-edge sweep, and has hinged leading and trailing flaps to increase maneuverability. The aircraft is often described as inherently unstable, relying upon a central computer and electronic fly-by-wire flight controls.
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<p>The F-16 pilot sits on a zero-zero ACES II (Advanced Concept Ejection Seat) canted to recline 30°. The cockpit has HUD and multifunction displays, a sidestick controller instead of a conventional control stick, and a one-piece canopy of blown polycarbonate which, in later versions, is lined with RAM (radar absorbent materials). Westinghouse APG-66/68 pulse-Doppler radar gives the F-16 'look down' capability and is being upgraded in the 1990s.
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<p>The F-16 is armed with an M61A1 Vulcan 20-mm cannon with 515 rounds, located on the port side of the fuselage at the blend between wing and fuselage. The F-16 carries up to a maximum of 29,450 lb (9,276 kg) of ordnance, including Mk 20 Rockeye and CBU-87 cluster bombs, Mk 83 and Mk 84 500-lb (227-kg) and 1,000-lb (454-kg) bombs, AGM-65 Maverick missiles, and GBU-10 and GBU-15 guided weapons.
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<p>F-16C/D blocks 25, 30 and 40 aircraft are powered by 27,600-lb (122.77-kN) thrust General Electric F110-GE-100 engines or improved versions. F-16C blocks 32 and 42 Falcons have 23,840-lb (1,0814-kg) thrust P&W F100-PW-200s. Later F-16s use IPE (Improved Performance Engines) of the PW-229 and GE-129 subtypes.
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<p>After defeating the Northrop YF-17 in a 'fly-off' contest, the YF-16 was chosen by the USAF on 13 January 1975. The USAF ordered eight full-scale development (FSD) F-16 airframes and the first (75-0745) flew at Fort Worth on 8 December 1976. The first two-seat FSD F-16B (75-0751) flew on 8 August 1977. The two-seat version retains wing and fuselage dimensions of the single-seater but sacrifices 1,500 lb (680 kg) of fuel.
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<p>In June 1975, four European countries (Belgium, Netherlands, Denmark and Norway) chose the F-16A. On both continents, an intricate MSIP (Multi-Stage Improvement Program) was launched to formalize cooperation in upgrading the aircraft on a planned, gradual basis. Numerous other foreign users have since adopted the F-16 Fighting Falcon.
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<p>Delivery of operational airplanes began in January 1979 to the 388th TFW at Hill AFB, Utah. F-16s went next to the 56th TFW at MacDill AFB, Florida, one of the USAF's RTUs (replacement training units) for the type.
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<p>Despite a GAO (General Accounting Office) finding of engine malfunctions, structural cracks and other teething problems, the F-16 developed into a superb fighter-bomber. The F100-PW-100 engine was new and experienced problems including ground-start difficulties, compressor stalls, fuel-pump breakdowns and afterburner malfunctions. Much of this was corrected early and the engine, employed on all F-16A/B models, has proved successful.
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<p>The first YF-16 (72-1567) was rebuilt in December 1975, with twin canards added, to become the USAF Flight Dynamics Laboratory's Control-Configured Vehicle (CCV). Fly-by-wire flight controls and relaxed static stability made the YF-16 an ideal candidate to evaluate control of an aircraft beyond conventional means, with independent or 'decoupled' flight surfaces to permit maneuvering in one plane without movement in another—for example, turning without having to bank. The YF-16/CCV and the AFTI F-16 (below) could rise or fall using direct lift, move laterally by direct side force, or yaw, pitch or roll regardless of the direction of flight.
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<p>General Dynamics converted the fifth FSD F-16A (75-0750) into the Advanced Fighter Technology Integration aircraft, or AFTI/F-16A (also klnown as the NF-16A). The AFTI/F-16 has a triplex digital flight-control system, larger vertical canard surfaces at the air intake and a thick dorsal spine. From 1982, it underwent a two-year program of test flights.
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<p>In recent years, the AFTI/F-16 has become associated with close air support (CAS) studies, and is now known as the AFTI/CAS F-16. Upgraded with an F-16C block 25 wing and F-16C block 40 features including APG-68 radar and LANTIRN interface, the AFTI/F-16 has been through a five-phase CAS evaluation program over 1988-1991, applying an automatic target hand-off system, Pave Penny laser-designator pod, and digital systems to the low-level battlefield mission.
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<p>Versions of the F-16A were also tested with APG-65 radar, with J79 engine, and with YJ101 engine. A proposal for an F-16 with a much-changed wing shape was made in February 1980. Known as SCAMP (Supersonic Cruise And Maneuvering Prototype) and later as the F-16XL, this was a rebuild with a 'cranked delta' wing. The F-16XL's fuselage was lengthened to 54 ft 1.86 in (16.51 m) and grafted on a cranked-arrow wing incorporating carbon composite materials to save weight while increasing area and allowing up to 17 stores stations.
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<p>The first of two F-16XLs (75-0749) with single seat and F100 engine flew briefly in the mid-1970s. The second F-16XL (75-0747; originally a single-seat FSD F-16A), now a two-seater with F110 engine, flew in the 1980s and competed unsuccessfully with the F-15E Strike Eagle. Had it been chosen for production, the aircraft would have been designated F-16F.
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<p>F-16A/B airplanes were built in blocks 1, 5, 10 and 15, all powered by the Pratt & Whitney F100. F-16C/D models are in blocks 25, 30/32, 40/42 and 50/52. C/D models in blocks 25, 30, 40 and 50 are powered by General Electric F110 engines, while otherwise identical ships in blocks 32, 42 and 52 have improved P&W F100s.
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<p>F-16A/B block 1s were early production aircraft (43 built), consisting of 21 F-16As and 22 F-16Bs distinguishable from later Fighting Falcons by their black radomes.
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<p>F-16A/B block 5s introduced the gray radome which is now standard. These 116 ships included 89 F-16As and 27 F-16Bs. F-16A/B block 10 consists of 170 airplanes including 145 F-16As and 25 F-16Bs, in addition to earlier, now upgraded, machines. F-16A/B block 15 (also known as MSIP I) introduced the first important changes to the F-16. Noteworthy is the extended horizontal stabilator, or 'big tail' now standard on these and all subsequent Fighting Falcons. Because of wing cracks and afterburner problems, the USAF is expected to retire pre-block 15 'small tail' ships by the mid-1990s, making these final F-16A/Bs the oldest F-16s to remain in service. Block 15 includes 455 American airplanes, including 409 F-16As and 46 F-16Bs.
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<p>Two hundred and seventy-two airframes in the F-16A/B block 15 series were converted to ADF F-16A/B block 15 (air defense fighters). In October 1986, the USAF announced that these aircraft would take over the ANG fighter-interceptor mission, defending North America from bombers and cruise missiles. Principal additions are the AIM-7 Sparrow radar missile and a spotlight. The ADF F-16A/B block 15 interceptor also has provision for AIM-120 AMRAAM, advanced IFF (indentification, friend or foe), and HF radio for long-range communications. ANG interceptor pilots are trained by the 114th Fighter Squadron, Oregon ANG, at Kingsley Field in Klamath Falls. The cost of maintaining ADF units was reviewed in light of reduction of the Soviet threat, and some ADF units have been re-roled for other tasks.
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<p>The F-16C single-seat and F-16D two-seat fighters introduced progressive changes to enhance Fighting Falcon capability to operate at night. The first F-16C flew on 19 June 1984. All C and D models have an enlarged base or 'island' leading up to the vertical fin with a small blade antenna protruding up from it. The space was intended for the ASPJ (airborne self-protection jammer) but the USAF had abandoned this program. F-16C and D models also employ Hughes APG-68 multimode radar with increased range, sharper resolution and expanded operating modes. There is provision for the AGM-65D Maverick, and a variety of avionic advances. These models also give the pilot a bigger HUD, and a function keyboard control at the base of the HUD (located in a console to his left in earlier ships), called 'up front' controls. A data display with key items of information is located beside the HUD in front of the pilot at 'design eye' level for HOTAS flying.
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<p>F-16C/D block 25 airplanes (also known as MSIP II), production of which began in July 1984, are powered by the F100-PW-200 and number 244 aircraft: 209 F-16Cs and 35 F-16Ds. The 27,600-lb (122.77-kN) thrust GE F110-GE-100 engine used in F-16 block 30s delivers about 5,000 lb (2,268 kg) more thrust than P&W engines. This powerplant change brought a need to alter contours of the F-16 air intake to accommodate the larger amount of air ingested. Because the change was not made at first, early F-16C/D block 30s (MSIP III) are 'small inlet' airplanes, the 1-ft (0.3-m) larger air intake having become standard for GE power on 'big inlet' ships from 86-0262 onwards.
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<p>F-16C/D block 32 airplanes are identical to those in block 30 except that power is provided by a 23,770-lb (10,782-kg) thrust F100-PW-220. Introduction of the 'dash 220' marks the maturation of the original F-16 engine. While the improved P&W engine is not as powerful as the GE powerplant, it is lighter and crew chiefs consider it 'smarter' and more dependable than Pratt & Whitney 200s.
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<p>F-16C/D block 30/32 aircraft have capability for AGM-45 Shrike I and AGM-88A HARM anti-radiation missiles, and AIM-120 AMRAAM. Avionics hardware changes are also introduced with block 30/32. A total of 469 of these airplanes was ordered during FY 1985-88, including 416 F-16Cs and 53 F-16Ds.
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<p>F-16C/D block 40/42 airplanes began to come off the Fort Worth production line beginning in December 1988. Among several F-16C/D blocks covered by MSIP III, this version introduces LANTIRN pods, GPS (Global Positioning System) receiver, HARM II, APG-68V radar, digital flight controls, automatic terrain-following, and (as a logical consequence) increased take-off weight. With this block comes the configured (formerly 'common') engine bay, with options for the GE F110-GE-100 (block 40) or P&W F100-PW-220 (block 42).
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<p>Greater structural strength increases the F-16C/D Night Falcon's 9-g capability from 26,900 lb (12,201 kg) to 28,500 lb (12,928 kg). The heavier all-up weight has resulted in larger landing gear to accommodate LANTIRN, bulged landing gear doors, and the move of landing lights to the nose gear door. Block 40/42 Night Falcons are also slated for Israel, Egypt, Turkey and Bahrain. USAF procurement of these derivatives eventually totalled 462, made up of 384 F-16Cs and 78 F-16Ds.
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<p>F-16C/D block 50/52 aircraft with IPE (Improved Performance Engine) are powered by the third major version of engines now in use—the GE F110-GE-129 and P&W F100-PW-229. These feature APG-68 (V5) radar and improved secure radios and radar warning receiver. Unless there is a change, the block 50/52 aircraft will be the last to be obtained for the USAF, which presently anticipates receiving a total of 241, comprising 201 F-16Cs and 40 F-16Ds.
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<p>Two hundred and forty-nine F-16 Fighting Falcons were deployed to Operation Desert Storm and flew almost 13,500 sorties, the highest sortie total for any aircraft in the war, while maintaining a 95.2-per cent mission capable rate, five per cent better than the F-16's peacetime rate. F-16s attacked ground elements in the Kuwaiti theater of operations, flew 'Scud' missions, and destroyed military production and chemical production facilities, and airfields.
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<p>Unless there is a drastic change of heart, procurement of the F-16 by the USAF will be terminated during FY.1994 with a contract for the final 12 of 2,208 aircraft, although Lockheed is pushing the idea of obtaining at least another 100 examples of the F-16C/D in order to release F-16A/B models for transfer to friendly nations. However, since there is already a substantial surplus of the older variants, this seems unlikely to occur.
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<p>Recent deliveries have been of the enhanced Block 50D/52D sub-types, which are optimised to perform the defense suppression role. Production of this model is expected to number 144 F-16Cs and 20 F-16Ds, all of which embody revised software as well as provision for the AN/ASQ-213 HARM targeting system and the 'Pave Penny' sensor pod. Although the AN/ASQ-213 is less capable than the F-4G's dedicated 'Wild Weasel' suite of equipment, the incorporation of an improved data modem in the Block 50D/52D machines permits transfer of threat location information from the F-4G to be accomplished via electronic means. The first such aircraft to enter service went to the 20th FW at Shaw AFB, South Carolina in the spring of 1993 and others have since joined the 52nd FW at Spangdahlem AB, Germany; the 366th Wing at Mountain Home AFB, Idaho and the 432nd FW at Misawa AB, Japan.
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<p>Looking further ahead, even though it appears unlikely that more new-build aircraft will be obtained, Lockheed certainly hasn't called a halt to efforts at improving the already impressive capabilities of the Fighting Falcon. At least three more versions form the subject of design studies and it is not beyond the realms of possibility that they will enter service with the USAF, either in new-build form or, as seems more likely, as a result of post-production modification projects. Such versions are known to include the Block 50 Plus, with a synthetic aperture radar mode for bad-weather munitions delivery as well as passive missile warning and terrain-reference navigation systems; the Block 60, with LANTIRN nav/attack avionics housed internally; and the Block 60/62, which is intended to satisfy a potential USAF requirement for a multi-role fighter and which would make use of F-22A technology.
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<p>Those projects may never come to fruition, but the future of the F-16 is assured and it will continue to be one of the most important USAF assets until well into the next century.
