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F-16: The Shattered Dream The F-16 was designed from the outset as a pure Air to Air fighter, but what eventually went into production wasn’t quite the envisioned dream. The dream was partly from renowned aircraft designer Harry Hillaker at General Dynamics,who in the mid 1960s spent many of his spare hours designing the aircraft of his dreams – “a lightweight, high-performance jet that could fly circles around all other fighters”. He got to work with a group of people that got dubbed the Fighter Mafia on what was eventually to be to be a “best effort” technology demonstrator for the USAF. The Fighter Mafia? Hillaker stated there were three core members of the Fighter Mafia, namely John Boyd, Pierre Sprey and himself. They had ideas that went against the grain of the USAF upper echelons at the time and they wanted a lower cost, lightweight Air to Air fighter. [1] There were other protagonists but regardless of who they were the Light Weight Fighter (LWF) would not have happened without their influence in the Pentagon. John Boyd Ex fighter pilot John Boyd who also now worked at the Pentagon had recently been applying his work on E-M theory to the design of the F-15. However he had in his mind a concept for a Light Weight Fighter (LWF) and he sat down with Hillaker and they started to put ideas together. Much has been written about Boyd but what we can say is that he was very well respected by most for his achievements, however he upset a lot of the establishment at the time which may have ultimately gone against him. In 1975 the Air Force awarded Boyd the Dr Harold Brown award (the highest scientific achievement granted by the Air Force), with a citation stating how E-M was used in designing the F-15 and F-16.[9] Pierre Sprey On the opposite end of the achievement spectrum was this guy, yes the same one that you may have seen recently on RT (Russia Today) going under the title of “F-16 designer” or even “creator of the F-16” (taking credit for dead peoples work……classy Pierre). [13] Pierre Sprey was at the time a civilian Defence Analyst (with no military background) at the Pentagon and his involvement in the F-16 seems to have been minimal. It consisted of collecting data on aircraft reliability, effectiveness and cost and analysing the data with Hillaker and Boyd. [1] Corams Book, “Boyd” makes out the inlet in the F-16 was positioned where it was due to a suggestion by Sprey [14]. Unsurprisingly this appears to be patently false.[21] Described by others who worked at the Pentagon at the time as a Luddite[28] and a gadfly[2] his name is regretfully part of this history. Was the LWF to be a day time only Visual / WVR fighter? yes and no! The USAF design goals for the LWF demonstrators stated only clear Weather and, day conditions with capability to be upgraded later to all weather & all light conditions. The Fighter Mafia didn’t want radars in the LWF did they? Corams Boyd [9] makes out the addition of a large ground mapping radar was a change not wanted, whereas Michel III [26] makes out the USAF added a Pulse Doppler radar that the Fighter Mafia completely opposed. Other available information suggests that Boyd did not want a Radar in the F-16 due to his experience of small radars in single man jets in the 1960s. A valid point at the time because they were very limited without a dedicated RIO/WSO as found in the F-4. He likely was surprised at how good the APG-66 was due to rapid advances in computing technology. [6] According to Herb Hutchinson, Boyd eventually agreed that the added capability to the F-16 was cost effective and mission effective. So the LWF was never going to get a radar or AIM-7 right? Err false……at the point the LWF prototypes were being built (now designated YF-16), they had provisions for AIM-7 and a bigger avionics package than was specified for the LWF requirements [7], and this was long before the USAF got their paws on it. If the LWF concept went into production it almost certainly (politics permitting) would have had AIM-7 and an APG-66 type FCR regardless, even if the radar had only A-A modes. In 1974 the USAF specified instructions to General Dynamics and Northrop near the end of the LWF project for the missionized USAF Air Combat Fighter they wanted. This included: “Air-to-air armament includes the carriage of four AIM-9J/L missiles, an M61 A1 20 mm cannon with 500 rounds capacity, and Group A provisions for carriage of two radar-guided missiles (replacing two AIM-9J/L IR missiles).” But the YF-16 had a tiny nose and no radar? It is important to ignore what the YF-16 looked like because it was a quick build technology demonstrator. It must be clarified that one of the YF-16s actually did have a radar[20] required for testing the Vulcan cannon. Some may be aware that the F-4A (F4H-1F) also received a complete nose job from block 3 to accommodate a larger radar.[25] Okay so why then did the production F-16A not carry the AIM-7 from the off? This one is less of a mystery but has been intertwined and confused with Fighter Mafia ideas and the LWF concept. Officially the USAF simply had no requirement for AIM-7s on the F-16A so they were never put on. General Dynamics did conduct proof of concept AIM-7 firing tests in November 1977, including conformal fuselage carriage, but no effort was made to develop this because it wasn’t required. [5] Unofficially and sadly it was 100% politics. There were zero technical reasons why the production F-16A didn’t carry AIM-7 from IOC in 1980, however there was a big political reason likely involving the F-15 and sources outside of Coram do verify this: Air Force four-star generals had ordered him not to put a Sparrow missile on the F-16 because they didn’t want it competing directly with the F-15.[3]. This consensus also being backed up by one of the initial Viper cadre in the late 1970s: “The lack of a radar missile capability for the Viper was pure politics. The radar was modified quite cheaply in late 70's to use the thing. Small CW antenna in the radome and a tuning doofer in the RIU, and presto!” [4] Myth of the simple Fighter Compared to the F-15 the F-16 was actually a far more technologically advanced design with far higher risk. This was down to several factors: · The F-15 was the first fighter to be procured in years by the USAF and was very costly, so McDonnell Douglas favoured a lower risk approach. [1] · To get the range and performance required for the size, the F-16 had to use a full on cutting edge Fly By Wire computer system and be longitudinally unstable. Such was the risk the design team had provisions for mounting the wing further back if the FBW system didn’t work with a penalty in range and performance degradation. [1] YF-16 wins the fly off but then what? After the fly off in 1974, the YF-16 was considered the better aircraft simply because it met the combat relevant tasks set by the USAF, whereas the YF-17 did not. Lower cost and the decision to use the F100-PW engine (also used in the F-15) no doubt also went in its favour. Once accepted the F-16 design was then handed to the US Air Force Configuration Control Committee (CCC) led by ex fighter pilot Alton Slay. Here the LWF concept was killed and a slight redesign turned the F-16 into the “multirole” fighter the USAF wanted with an emphasis on the A-G role. [2] What is clear is that they enlarged the fuselage to add more fuel (to retain the range) and increased the wing area from 280sqft to 300sqft (to retain some manoeuvrability), the horizontal tail and ventral stabilisers were also enlarged [8]. What is less clear is the various amounts of weight that was added. [15] Boyd it seems did not agree that 300sqft was a big enough increase to retain the original manoeuvrability and spent considerable effort to get it increased to 320sqft but alas failed to get this changed – he blamed the F-15 and politics as part of the USAF decision. [9] A multirole F-16? When the F-16A first rolled off the production line, despite being bigger it was actually lighter than the Prototype YF-16 used in the flyoff (which was just a quicky build tech demonstrator). [8] It was however not the LWF the mafia had hoped for and was never designed for carrying loads of bombs and external ECM pods. Hillaker stated that if he had designed the F-16 as a multirole jet as the USAF wanted to use it he would have designed it differently. The Harry Hillaker F-16 design with emphasis on A-G was the excellent if underpowered F-16XL. [1] F-16XL - Fly super jet fly! (f-16.net) Okay so was having no AIM-7 capability a problem? F-16s would not see operational AIM-7 capability till around 1989 on the USAFs F-16A ADF [16]. The AIM-7 was only certified on the F-16C post 1992 by General Dynamics who had to fund it themselves. The AIM-7 was never part of the USAF F-16 plan at all and the F-16 ADF really was a one off. It seems the AIM-120 was hoped to be in service by 1985. The first "guided" F-16 AMRAAM launch took place in 1985 however operational service was delayed six or so years. This sounds like criminal negligence on behalf of the USAF because with no AIM-7 but still a major A-A role for USAF flyers in the Cold War it didn’t sound like a great deal for the flyers. There was some saving grace however, being the 1980s there were a lot of ways around the relatively primitive radar and missile technology of the era [22] and the F-16 despite the enforced lower performance was still in some respects superior to the F-15 close in. [23]. In the 1994 William Tell Air Superiority competition both participating Air National Guard units flying F-16A ADFs finished top and wiped the floor with five regular USAF F-15C units. This was not a surprise to anyone in the F-16 community. So what would a LWF F-16A look like if the USAF had accepted it in an alternate reality? · Smaller with 280sqft wing area and less fuel (but similar range). · Around 13000 lb empty weight. [15] · Engine: Same F100-PW-200. · Avionics: APG-66 with nose enlargement, RWR. · AIM-9, AIM-7 and Cannon armament. · Drop tanks. Hillaker stated he thought if the F-16 had gone to production as intended then only about 300 would have been procured by the USAF………..just like the F-104.[1] Were the USAF right to do a half arsed redesign on it? History would say they were. It was more useful because A-G is where most of the action has been and despite the lower A-A performance it turned out to be more than good enough in the A-A role. New F-16s still roll off the production line in 2016 (nearly 40 years of continuous production) and the F-16 is still seen as a benchmark design to compare others to, so can’t be too bad. It wasn’t all roses though - with the “Multirole” F-16 the USAF had plans to add everything but the kitchen sink to it over time, to the inevitable point where they had structural failure at Block 30 when trying to wedge such things as LANTIRN onto it [24]. That meant the structure had to be totally redesigned at Block 40/42 and accounts for much of the weight increase at those and later blocks due to the effort to turn it into a bomber (Switching to the F-16XL might have been less hassle after all!). Later projects to improve performance on the production F-16 were also cancelled, notably Agile Falcon [17] in the late 1980s (to make the wing bigger - kinda similar to what Boyd suggested originally) and Multi Axis Thrust Vectoring (MATV) [18] in the early 1990s. Getting old and fat The production F-16 got fatter and fatter so here is a very simple chart that shows Wing loading increase over time. And the F-16 today The F-16E may have the highest Wing Loading on the chart but it is no doubt the best production F-16 for real combat today (before the F-16V upgrades take place). AESA radar, sensor fusion, internal ECM suite, towed decoys, FLIR, and CFTs for extra range……..all the important parameters of a fighter today require space in the airframe……..so not completely suited to a LWF concept……….. But it was a nice dream while it lasted…………… References: [1] Interview: Harry Hillaker - Father Of The F-16 http://www.codeonemagazine.com/article.html?item_id=135 (Accessed 2016) [2] (Michel III, M.L, 2006) THE REVOLT OF THE MAJORS: HOW THE AIR FORCE CHANGED AFTER VIETNAM [3] Retired General Mike Loh who worked on Alton Slays USAF CCC team: In June 1972, the Air Force had sent Loh to the Massachusetts Institute of Technology for a master’s degree in aeronautical engineering and assigned him to the prototype office at Wright-Patterson Air Force Base in Ohio to manage the budget, contracts, and overall engineering for the Lightweight Fighter. When the F-16 was selected, the Air Force formed a system program office at Wright-Patterson, where Loh signed on as director of projects, with the responsibility to integrate the avionics and weapons systems on the airplane. But he was in a quandary. Air Force four-star generals had ordered him not to put a Sparrow missile on the F-16 because they didn’t want it competing directly with the F-15. But they didn’t say anything about inventing a new missile. “I pursued a lightweight radar missile very quietly, as an advanced development project, with no strings to the F-16 or any other fighter,” Loh says. “I worked quietly with missile contractors and the Air Force Development Test Center at Eglin to put together radar missile designs that could fit on Sidewinder stations. This initiative later turned into AMRAAM, the Advanced Medium-Range Air-to-Air Missile.” (Bjorkman. E, 2014 ) The Outrageous adolescence of the F-16, Air and Space Magazine http://www.airspacemag.com/military-aviation/The-Outrageous-Adolescence-of-the-F-16-241533731.html (Accessed 2015) [4] “The lack of a radar missile capability for the Viper was pure politics. The radar was modified quite cheaply in late 70's to use the thing. Small CW antenna in the radome and a tuning doofer in the RIU, and presto!” http://www.f-16.net/forum/viewtopic.php?f=37&t=8478&hilit=Boyd+love&start=15 Pat “Gums” McAdoo http://www.f-16.net/interviews_article28.html [5] Information provided by GD engineer **John G Williams [6] “ I will add that JB was totally against putting a radar in the Viper, as the radars he was familiar with (and that would have fit in the nose) were pretty useless and for the most part was weight he felt the F-16 could do without. I suspect he was surprised with how good the radar turned out to be (although still very weak compared to the Eagle)”. [Roscoe retired USAF Fighter Pilot] http://www.f-16.net/forum/viewtopic.php?f=37&t=8478&hilit=Boyd+love&start=15 [7] Although the LWF requirement specified only minimal electronics , the design team recognized that an operational aircraft would probably require a heavier and more bulky avionics package. The decision was made to size the aircraft to carry heat-seeking Sidewinder missiles plus an M61 cannon, but to make provisions to allow Sparrow radar-homing missiles to be carried at a later date should this be required. F-16 Design Origins, Code One Magazine http://www.codeonemagazine.com/article.html?item_id=131 (Accessed 2015) [8] “ I was a structural engineer on the YF-16 and F-16 flight test teams, so was familiar with weights at the time. Forty years is too long to remember all the numbers, but when the F-16 was in early flight test, I did a weight comparison between the two and was very surprised to find the F-16 empty weight was less than the YF-16. So, the YF-16, designed for 6.5g at 14900 lb was heavier than the F-16, designed for 9g at 22,500 lb. Don't confuse the design weight as the actual weight, two totally different things. Here's why the YF-16 was heavier. First, it had a much larger structural margin. meaning it was designed for 25% overload capability, because no 150% static test was performed. Second, it was not a refined structural design, either design loads or stress analysis. If there was any doubt about load or stress, it was made a little heavier. Third, manufacturing processes were not refined. It was built as cheaply as possible. Remarkable, when you consider the added g and design weight, larger wing, horizontal tail, and ventral fins, and longer fuselage of the F-16, in addition to an 8,000 hour service life.” [John G Williams**] http://www.f-16.net/forum/viewtopic.php?f=58&t=25121&p=266379#p266379 [9] (Coram. R, 2004 ) Boyd: the Fighter Pilot that changed the art of war [13] Some of these gems are captured around 36:03 on this video. https://www.youtube.com/watch?v=-HVY6Fdc2CM [14] (Coram. R, 2004 ) Boyd: the Fighter Pilot that changed the art of war p246. [15] Source [2] (Michel III) claims 2 tons (4000 lbs) and source [9] (Coram) claims 3000 lbs. Simply using the same wingloading value as Boyd wanted at 320sqft but for a 280sqft design gives around 13000 lbs so may as well go with that. [16] F-16A ADF http://www.f-16.net/f-16_versions_article14.html [17] Agile Falcon http://www.f-16.net/f-16_versions_article21.html (Camm F) The F-16 Multinational Staged Improvement, RAND N3619. [18] F-16 MATV http://www.f-16.net/f-16_versions_article19.html (Accessed 2016) Thrust Vectoring in the real world, Code 1 Magazine http://www.codeonemagazine.com/article.html?item_id=163 (Accessed 2016) [19] Egyptian Block 32 with AIM-7 http://www.f-16.net/f-16_users_article4.html (Accessed 2016) Note: this is not for certain because according to General Dynamics (Lockheed Martin) the AIM-7 was only certified on the F-16CD in 1989. [20] “ I am not sure where the false story of no radar on the YF-16 started, but I guarantee you it was there. It was not a radar like you might expect, with a scanning antenna inside the radome and a glowing, flickering screen in the cockpit, but it was a radar nonetheless. The function of the radar was to provide range-only information for the gun sight. Although I'm not certain, I seem to recall only one of the airplanes had a gun, as a cost saving measure. If so, only one airplane would have had the radar system.” [John G Williams**] “Confirming that only the second prototype had a ranging radar installed, the Solid State Range-Only Radar (SSR-1) developed at General Electric, AESD, Utica, New York. “ [http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA041197 ] http://www.f-16.net/forum/viewtopic.php?f=23&t=28763&p=312806#p312806 (Accessed 2016) [21] The General Dynamics team also studied several different air intake configurations before settling on the final air intake located underneath the nose. The ventral location for the intake was chosen to minimize the sensitivity of airflow into the engine to high angles of attack. At a 20-degree AoA, the local flow direction to a ventral intake was only ten degrees below datum, as compared to 35 degrees in the case of side-mounted inlets. The design team had actually started with a chin-mounted Crusader-type intake, but it was gradually pushed further and further back to save weight until the process finally had to be halted to keep the intake ahead of the nosewheel. There are some disadvantages to such an air intake location --- the mounting of the inlet underneath the fuselage is potentially dangerous to ground personnel and appears at first sight to invite foreign object damage (FOD) to the engine by the ingestion of stones and other runway debris into the intake. However, it avoids the gun gas ingestion problem, and since the nosewheel is further back, it avoids nosewheel-induced FOD. In order to save weight and complexity, the geometry of the intake was fixed. F-16 LWF http://www.f-16.net/f-16_versions_article4.html (Accessed 2016) [22] (Anderegg C.R, ) SIERRA HOTEL FLYING AIR FORCE FIGHTERS IN THE DECADE AFTER VIETNAM, Chapter 17 [23] “Throughout the book I have attributed credit where it is due. However, many statements in the book are my own. For example, in the last chapter I write that the F–16 is a better day, visual dogfighter than the F–15. F–15 pilots who read that statement will howl with anger. Sorry, Eagle pilots, but I flew the F–15 for over ten years, and that’s the way I see it.” (Anderegg C.R, ) SIERRA HOTEL FLYING AIR FORCE FIGHTERS IN THE DECADE AFTER VIETNAM “If my memory serves me right, our pair won the 2v2 training session, but in a 1 v1 scenario, the Baz was no match for the Netz. The latter jet has to be the worlds best WVR fighter platform.“ [baz [F-15] pilot Yorem Peled ] (Aloni, S, 2006) IDF/AF Israeli F-15 Eagle units in Combat, Osprey [24] “There was a total re-engineering of block 40 structure following a static test failure of a block 30 airframe. Test failure was at 137% of limit load, well short of the 150% requirement. Patches applied to block 30 airplanes allowed those airplanes to continue flying. Airplane weight had increased with each block from block 1 on and it finally caught up with the true capability. So Block 40 was essentially a new structure, much stronger than previous blocks. The block 40 LANTIRN installation was also a big driver in redesign because it drove the CG forward. That shift required more down tail trim load, increasing fuselage, tail, and wing loads. So block 25 structure is not close to the block 40 or 50 structure in static or durability capability.” [John G Williams**] http://www.f-16.net/forum/viewtopic.php?f=2&t=27459&p=299748#p299748 (Accessed 2016) [25] F-4A http://www.joebaugher.com/usaf_fighters/f4_2.html (Accessed 2016) [26] the Configuration Control Committee ordered it equipped with a small but highly capable pulse Doppler radar, something the Critics had adamantly opposed. (Michel III, M.L, 2006) THE REVOLT OF THE MAJORS: HOW THE AIR FORCE CHANGED AFTER VIETNAM [28] Retired General Mike Loh: Loh says that each Fighter Mafia member had a different agenda. “Boyd was unquestionably the leader and dominated the crusade. His motivation was to vindicate his EM theory, and he wasn’t concerned about any mission beyond close-in air-to-air combat. He spent hours debating anyone who challenged his views.” On the other hand, General Dynamics [Author: Pentagon not GD! ] system analyst Pierre Sprey “was a true Luddite, opposed to any advanced technology,” says Loh. “His agenda was to produce the cheapest fighter for daytime air combat in Europe against Warsaw Pact forces.” (Bjorkman. E, 2014 ) The Outrageous adolescence of the F-16, Air and Space Magazine http://www.airspacemag.com/military-aviation/The-Outrageous-Adolescence-of-the-F-16-241533731.html (Accessed 2015) **John G Williams was a structural flight test engineer at General Dynamics, and worked on programs including the YF-16, F-16, F-16XL and F-2A.