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F-16XL: A great idea at the wrong time 

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The F-16XL was a design named after………..a golf ball………..that being the Top Flite XL for any who ever played Golf. Harry Hillaker was also a golfer….one with a problem in that the USAF wanted to use his A-A fighter (F-16A) in an A-G role hanging lots of pods and bombs off it which was just not on! 


So, what did he do and why?
He and his design team at General Dynamics redesigned the F-16 to be more suitable to an A-G role using such concepts as high internal fuel loads and conformal carriage of weapons to get that nasty drag and radar cross section right down. In fact when he first started going to the Air Force with plans for the XL they were so enthusiastic about it they apparently accused him of holding the design back so that they (General Dynamics) could sell the F-16 twice.

Goals to improve operational effectiveness included:
•    Improve the A-G role without degrading A-A capability.
•    Increased survivability, though increased speed, manoeuvrability and low radar cross section.

The idea was to replace the F-16 and remain a lower cost fighter to the high cost F-15.


So, some concept demonstrators were knocked together for testing?
Yes, two of the Full Scale Development (Block Zero) F-16s were converted by doing such things as stretching their fuselages, removing the ventral strakes and gluing on some new cranked delta wings or double deltas. F-16XL-1 was 75-749 and had the F100-PW-200 engine, and F-16XL-2 was 75-747 which started life as single seater but was converted to the XL as a duel seater with the higher thrust F110-GE-100 engine.



Were the goals met?
Most of them, the low drag weapons carriage and lots of internal fuel meant vastly improved range over the F-16A (that already had comparative long legs), carried more A-G weapons, with ability to lug along 6 x A-A missiles on top. High AoA handling and instantaneous turn was improved. Cruise speed was also improved. 

This is a part of a 1989 write up by General Dynamics test pilot Joe Bill Dryden:
Pitch rate in all configurations was as good as to slightly better than a Block 10 A model (No slouch in itself) and the roll response was better. On several occasions, during demonstrations with VIPs, I had to remind them that we had 12 MK82s on the airplane! They would frequently forget because of the ease with which the airplane would attain high airspeed…….How high an airspeed? Mull this over for a while, you put 6 MK82s on your little airplane, plus tanks and try to get close to my radius. ill put 12 x MK82s on board with no tanks, still go further than you can and for the same fuel flow by going 60 to 80 knots faster than you. I risk going in to the classified arena, but with the right fuses on the bombs you could get well on the plus side of the Mach, all the while enjoying a much better ride. 


Is there a but here?
Yes using the F100-PW-200 engine from the F-16A, it was a tad underpowered, more F-14A than F-16A………..so take off requirements were nowhere near and some of it’s A-A capability was a bit degraded you could say.

Perhaps an example from one of the Red Eagles pilots who flew some BFM against it in a MiG-21F-13:
[Red Eagle Matheny flying the MiG] “We briefed each other about our airplanes and they [Edwards F-16XL pilots] turned to me and said they would be all over me – they had a roll rate of 800 degrees per second, which was the fastest in the inventory. – I got to thinking about that and it turned out the roll rate meant nothing. The problem with that airplane[F-16XL] was that it was a big bleeder: it just bled speed like nothing else when forced to turn hard – I ate them alive in the MiG-21. The F-15E on the other hand was a pretty good performer – they resisted the urge to get slow and jump in a phone booth with a MiG. They flew around the ranges at low level trying to burn off all this gas and he still needed to burn off more when we joined up on each other”.


Could they not have improved that somewhere?
Potentially, the second F-16XL had higher thrust F110-GE-100 engine but unfortunately the majority of the evaluation data and the Dual Role Fighter evaluation was done with the lesser thrusted F-100-PW-200. In fact Harry Hillaker stated they were not allowed to use the GE engine in the evaluation (see below) for whatever reason. NASA later got it supercruising with a F-100-GE-129 (29,500 lbs class), and by the late 1990s both General Electric and Pratt & Whitney offered suitable engines with a potential max thrust class to 36,000lbs and 37,000 lbs respectively.




Was there some competition against the F-15 at some point?
There was a USAF competitive evaluation originally called the Enhanced Tactical Fighter (ETF) competition, which in 1981 was renamed to became the Dual Role Fighter (DRF) competition. Technically not really a competition because both were evaluated and flight tested to totally different sets of conditions and to different flight test plans it seems.


Why did the USAF run this evaluation?
It was felt by some in the USAF the F-111F was becoming a bit outdated and instead of just an upgrade they wanted something that had A-A capability and a good precision night strike role against the Soviet masses.


So, they chose two short assed fighters to replace the F-111?
Pretty much – they would both get LANTIRN eventually and have a good A-A capability but still lacking in range.


Surely the F-16 was cheaper was it not?
On unit cost and cost per flight hour yes – but the USAF considered the F-16XL a radical new airframe compared to the F-15E, which was considered just a modification, so the USAF estimated research and development cost would be higher for the F-16XL.


Okay but in the end the F-15 was chosen as the winner and that was that.
No – following the DRF decision that the F-15E was going into production in February 1984, the USAF announced its intention to put the Single seat F-16XL into production anyway with the designation F-16F. So, work began on the F-16F design concept and Full Scale development into 1985.


So where is it then?
The program was terminated in late 1985 by the USAF it later appears there was no budget for every program out there such as the ATF (F-22) and black projects such as F-117 that were unknowns to most who ran the DRF so sadly the F-16F had to take the chop - basically lack of funding finally killed it off.





End of the F-16XL – not quite
The two F-16XLs were given to NASA in the late 1980s for various types of flight testing and we can thank them for taking some time to research into the history of the F-16XL and providing useful information on it. 



But there’s more
An interesting rebuttal, ten years after the DRF, written by Harry Hillaker in response to an article in Aerotech News and Review which perhaps gives a passionate and better insight into how farcical some of these things can be:


As the recognized “Father of the F-16,” and Chief Project Engineer during the concept formulation and preliminary design phases of the F-16XL and Vice President and Deputy Program Director during the prototype phase, the article was of considerable interest to me. The disappointment was that only one side of the issue was presented, a highly biased, self-interest input that does not adequately, nor accurately, present the real story of the selection of the F-15E.

First, it should be understood that we (General Dynamics) did not initiate the F-16XL as a competitor to the F-15E, then identified as the F-15 Strike Eagle. We stated as unequivocally as possible to the Air Force, that the Dual-Role mission should be given to the F-15: that the F-15 should complement the F-16 in ground strike missions in the same manner that the F-16 complements the F-15 in air-air missions. A fundamental tenet of the F-16, from its inception, has been as an air-air complement to the F-15—no radar missile capability, no M=2.0+ capability, no standoff capability: a multi-mission fighter whose primary mission was air-surface with backup air-air capability.

We proposed the F-16XL as a logical enhancement of its air-to-surface capabilities. The F-16C represented a progressive systems enhancement and the XL would be an airframe enhancement optimized more to its air-surface mission—lower weapons carriage drag and minimum dependence on external fuel tanks. 

The statement that “a prototype version of the F-15E decisively beat an F-16 variant called the F-16XL,” is misinformation. I don’t know what was meant by “beat,” it is patently true that McDonnell-Douglas clearly won what was called a “competition.” However, by the Air Force’s own definition, it was, in reality, an evaluation to determine which airplane would be better suited to the dual-role mission. In a formal competition, each party is evaluated against a common set of requirements and conditions. Such was not the case for the dual-role fighter. The F-15 Strike Eagle and the F-16XL were evaluated and flight tested to different sets of conditions and to different test plans—no common basis for evaluation existed.

The F-15 had only one clear advantage in the evaluation—a “paper” advantage. The weapon loading for one of the missions used in the evaluation precluded the use of external fuel tanks on the F-16XL; the F-15 could carry that particular weapon loading and still carry external fuel tanks, the F-16XL could not. That one mission was the only place the F-15 had a clear advantage. (It should be noted that a fundamental design feature of the XL was the elimination of external fuel tanks with their attendant restrictions on flight limits and their weight and drag penalty.)

Further, the Air Force would not allow us to use the GE F110 engine in our proposal even though the No. 2 XL, the 2-place version, was powered by a F110 engine and provided better performance than the P&W F100 engine. And although you would expect the F-16’s clear advantage to be cost, the Air Force treated the F-15E as a simple modification to a planned production buy and the F-16XL as a totally new buy. Neither airplane used in the flight test evaluation was a “prototype” of a dual-role fighter. The F-15 was closer systems and cockpit-wise than the F-16XL and the F-16XL was closer, much closer, airframe-wise. 

The F-16XLs were designed to, and flew, at their maximum design gross weight of 48,000 pounds, whereas the F-15, more than once, blew its tires while taxiing at 73,000 pounds, well below its maximum design gross weight [which was 81,000 pounds], a condition not demonstrated in the flight test program.

In a meeting that I attended with General Creech, then TAC CINC [Commander-in-Chief], the general stated that either air¬plane was fully satisfactory. When asked why he and his staff only mentioned the F-15 (never the F-16XL) in any dual-role fighter statement or discussion, he gave a reply that was impossible to refute, “We have to do that because the F-16 has a heart and soul of its own and we have to sell the F-15.” I’ll have to admit that I sat mute upon hearing that statement because there was no possible retort.

We had no allusions as to what the outcome of the Dual-role fighter “competition” would be and debated whether to even respond to the request for information. We did submit, knowing full well that it was a lost cause and that to not submit would be an affront to the Air Force who badly needed the appearance of a competition to justify continued procurement of the F-15—they had patently been unable to sell the F-15 Strike Eagle for five years. As is the case with too much in our culture today, the Air Force was more interested in style, in appearances, than in substance.

Even today, I feel that giving the F-15 a precision air-surface capability was proper and badly needed. What continues to disturb me is that the F-16XL had to be a pawn in that decision and had to be so badly denigrated to justify the decision—a selection that could have been made on its own merits.


And finally 
The concept of retaining performance with a usable Air to Ground loadout lives on today in the form of the F-35 Lightning II.......which comes with a 43,000 lbs thrust class engine to start with.



General Dynamics F-16XL  (F2275)














Page 267 Red Eagles (Davies.S), Osprey publishing 2008 - Matheny flew the MiG-21F-13 against the F-16XL and F-15E concept demonstrators. 
Elegance in Flight (Piccirillo.AC), 2014 National Aeronautics and Space Administration (NASA) – Chapter 7: The Dual Role Fighter competition. 
Code One Magazine, July 1989 (General Dynamics) Vol 4 No 2 -The F-16XL flies again 
Code One Magazine, July 1991 (General Dynamics) Vol 6 No 2 – Interview with Harry Hillaker

1999 Aviationweek online: http://aviationweek.com/awin/pws-229a-edging-close-500-hours
Pratt&Whitney's self-funded F100-PW-229A - a re-fanned F100 fighter engine that can produce as much as 37,150 lbst. - is edging close to 500 total hours of run time

1998 General Electric online: http://www.geaviation.com/press/military/military_19980907.html
Designated the F110-GE-129 EFE (Enhanced Fighter Engine), the engine will be qualified at 34,000 pounds of thrust and offered initially at a thrust rating of 32,000 pounds, with demonstrated growth capability to 36,000 pounds.


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Very interesting. I personally don't like the look of the F-16s that much, but the XL is one of my favourite aircraft. It's sad to see it was that close to becoming a reality. Maybe GD should have offered it themselves for export as Northrop with the F-20.

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I remember reading that it was thought too advanced for export at the time but damned if I can find the source. Also without a bulk order from the US the unit cost would probably be a lot higher considering the small numbers that normally get exported (assuming there weren't further development costs on top of that).

After the XL they developed a lower cost version for export based on the standard F-16C/D..............this being the F-16ES (Enhanced Strategic)....which lost to the F-15I (Another F-15E type) in a later competition for Israel. This was later developed into the F-16E/F Block 60 for the UAE.

You may have noticed that the Block 50/52 Plus with CFTs today that do get exported are advertised with the same same Max take off weight (48,000 lbs) as the XL had in 1982.



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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.
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      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]
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      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]
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      This one is less of a mystery but has been intertwined and confused with Fighter Mafia ideas and the LWF concept.
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      F-16XL - Fly super jet fly! (f-16.net)
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      Getting old and fat
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      And the F-16 today
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      [1] Interview: Harry Hillaker - Father Of The F-16 http://www.codeonemagazine.com/article.html?item_id=135 (Accessed 2016)
      [3] Retired General Mike Loh who worked on Alton Slays USAF CCC team:
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      Pat “Gums” McAdoo http://www.f-16.net/interviews_article28.html
      Information provided by GD engineer **John G Williams
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      F-16 Design Origins, Code One Magazine http://www.codeonemagazine.com/article.html?item_id=131 (Accessed 2015)
      “ 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.
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      (Coram. R, 2004 ) Boyd: the Fighter Pilot that changed the art of war
      Some of these gems are captured around 36:03 on this video.

      (Coram. R, 2004 ) Boyd: the Fighter Pilot that changed the art of war p246.
      Source [2] (Michel III) claims 2 tons (4000 lbs) and source [9] (Coram) claims 3000 lbs.
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      F-16A ADF http://www.f-16.net/f-16_versions_article14.html
      Agile Falcon http://www.f-16.net/f-16_versions_article21.html
      (Camm F) The F-16 Multinational Staged Improvement, RAND N3619.
      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)
      Egyptian Block 32 with AIM-7 http://www.f-16.net/f-16_users_article4.html (Accessed 2016)
      “ 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)
      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)
      “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.”
      “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
      “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)
      F-4A http://www.joebaugher.com/usaf_fighters/f4_2.html (Accessed 2016)
      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
      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.
    • By MigBuster

      Northrop fighter programs and luck are not things you will often hear in the same sentence. Here we look at the short lived Tigershark and some of its contenders for the lucrative 1980s export market.
      In the 1960s and through the 1970s Northrop produced and sold the superb F-5AB Freedom Fighter and F-5EF Tiger II to the export Foreign Military Sales (FMS) market. In fact over 30 countries had procured 2600 F-5s in 28 different configurations by the mid-1980s.
      In the late 1970s Taiwan had a requirement for a fighter that could fire BVR missiles like the AIM-7 – unfortunately the US government had to appease mainland China so the F-4/F-16/F-18 were out……… and so the US Department of Defense (DOD) asked Northrop to adapt the F-5E.

      F-5E Aggressor (Airliners.net)
      Sadly, with AIM-7s and a bigger radar, performance of the new F-5E was lackluster and Taiwan was not interested. So, the DoD asked Northrop to look into a more suitable configuration, which ended up with a new F404 engine and the designation of F-5G.
      The Carter administration at the time decided to put a cap on exports to certain developing countries and stipulated the US would only export fighters that were modifications of existing aircraft and thus "inferior" to US front line fighters. Also, any company submitting proposals had to fund it themselves! The ruling favoured the less advanced F-5G and not the F-16A, so with Northrop already having the F-5 market to themselves it sounded like a risk worth taking.
      The FX proposal (F-5G Vs the F-16-79)
      The requirement for the FX was for a fighter with performance somewhere between the F-5E and the F-16A, and so Northrop and General Dynamics submitted their proposals.
      Northrop F-5G
      The proposed F-5G turned out to be far superior to the F-5E, the choice of GE 404 turbofan engine in 1978 gave the F-5 around 60% more thrust (16,000 lbs max) and really was the jewel in the crown here.  This engine was also being used for the FA-18 and despite not being mature it had potential to be simpler, lighter, more reliable with less IR signature than the old turbojets (like the J79) with far less fuel consumption. With Digital Engine Controls the pilot didn’t have to worry about compressor stalling the thing. This certainly looked to have superior performance to the F-16-79 on paper.
      Northrop would have to develop avionics inferior to those in the F-16A for export purposes and looked at bids from Westinghouse, Emerson, Hughes, Norden and General Electric (GE) however none were chosen before the F-5G configuration had to be upgraded.
      General Dynamics F-16-79
      RAND called the F-16-79 half hearted, however General Dynamics had to find ways to cripple the F-16 in certain areas and one way to do this was to use the J79-GE-17X engine. The idea was that there were a lot of used J79s available in the world………so in theory this would be cheaper and easier to maintain and upgrade for these export customers.
      ·         The J79 engine was a slightly enhanced version of that in the F-104 & F-4 (was originally for the F-4). It had around 18,000 lbs max thrust and a bit more with a feature called “Combat Edge” that could be used for very short periods. ·         The F-16-79 had over 2000 lbs extra weight due to the heat shielding for the J79 and different Air intake and changes to the rear of the fuselage. ·         Range was significantly reduced. ·         Despite inferior performance to the F100 in the F-16A, the F-16-79 was actually faster top end due to the J79 and the different air intake. It is the only F-16 to fly over M2.1 in level flight as known.  
      Plenty flew the converted F-16B Block 0 (75-0752) and no one was impressed. It lacked performance where it mattered and more importantly the USAF were not flying it. For some reason Foreign Military Sales (FMS) customers decided to get delusions of grandeur at that period in time and expected to fly what the top air forces flew.

      F-16-79: note the very different engine! (Lockheed Martin)
      Disaster strikes
      As is life with any risks a government can come in change things for everybody (not just large corporations). In 1981 Jimmy Carter was out and Ronald Reagan (The actor!*) was in the White House and things quickly went south. Carters export policy was backed at first but it would seem export customers were not happy unless they were flying the same toys as the USAF. Export restrictions were lifted in 1983 and the F-5G was now competing against the real F-16A. (bollox)
      Let’s look at what Northrop was now faced with:
      ·         The F-16 was an established Air Force program with a Multi Staged Improvement Program and established logistics chain. ·         The USAF flew the F-16……………. again FMS customers were now picky and wanted to fly a jet the USAF flew and supported. ·         The F-16A was superior in turn performance, range, payload, comparable in climb and had better growth potential. ·         Buying more F-16s would favour the US by keeping the cost of them lower and the cost was now getting lower due to more buys from the Reagan Administration.    

      Ronald Reagan in Spitting Image form (ITV)
      Changing a Tigers stripes
      Not giving up Northrop decided to roll up their sleeves and get busy……or throw lots of money at the problem. All they had to do was make the F-5G beyond exceptional and also somehow pander to the US Government and the USAF to get them to buy it…. simple.
      Northrop now had to market the F-5G as a 4th Generation jet somehow, so the F-5G first became the Tigershark, which later became the F-20A Tigershark.
      Northrop had decided to concentrate all their funds on the one area they could compete………. that being avionics.
      The F-20A takes off
      The First Pre-Production Tigershark (82-0062 / GG1001) first flew in April of 1982 with a 16,000 lb thrust YF404 engine and revised rear fuselage with larger tail. It also had an hydromechanical flight control system with a computer-controlled Augmentation system (CAS)

       F-20 #1 (Northrop Grumman)
      Avionics extraordinaire
      In June 1981 Northrop had taken the step of telling General Electric (GE) to build a radar above and beyond the export spec and ideally superior in every way to the AN/APG-66 in the F-16A except range………. this was given the designation AN/APG-67.
      Ex USAF fighter pilot Pat “Gums” McAdoo was hired by Northrop as a consultant and used / saw some of the avionic developments, and confirmed they were far better than what was in the F-16A and in some ways better than what was being done for the F-16C Block 25 at the time.
      ·         Pilot interface was very easy to use for non-geeks and had been developed partly by an ex F-100 pilot. Some of these concepts were similar to the FA-18 and some found their way into later versions of the F-16C ·         The APG-67 radar was way Beyond the basic APG-66 radar and had more modes such as Track While Scan, Velocity search and a great Ground Map ·         Ring-laser Inertial Navigation System (INS) made start up very quick. ·         Had visual and radar bomb modes (CCIP / CCRP). ·         Flight control system in development was similar to the FA-18 a Fly By Wire augmentation system with hydromechanical backup.  
      The F-20 was the ideal foreign military sales jet. 
      It had short legs, but very quick response times from a cold start. The RLG inertial was awesome. The radar was way beyond what the Viper had at the time - track-while-scan, velocity search, really nice ground map, etc. The data entry design was awesome. Using the entry panel below the HUD was really easy,
      The most surprising thing was the MacIntosh-style stuff on the MFD's. I had not even seen a MAC when I showed up. But one great example was the radar display on one of the MFD'S. If you moved the cursor over to a radar mode or a range indication, then you got a pop-up menu and could cursor to desired mode and hit the "designate" button. 
      Pats involvement also gives us some insight into what the USAF considered important in a combat jet at that time. The avionics were vastly improved thanks to digital computers but they were still just a step up from the 3rd Gen paradigm with many flaws.
      The F-20 was a very capable interceptor with a great radar and great performance. RLG inertial that took less than a minute to align, TWS radar, extremely easy to use all the avionics. In short, I liked it. But I liked the Viper more, despite its crappy hands-on controls compared to the F-20. It had better turn performance and much better legs and could carry more pig iron.

      AN/APG-67 in TWS mode (Northrop Grumman)

      Head Up Display (HUD) in CCIP mode (Northrop Grumman)
      Let’s sell this thing anyway
      Another consultant and ex USAF legend working with Pat at Northrop was Charles “Chuck” Yeager who also flew the pre-production birds.
      Chuck was used on the promotional videos and you can hear the sales pitch here:
       How to rub salt into wounds  
      In 1982 (Just as the F-20 marketing began to get into swing) under pressure from China, Reagan had vetoed the export of the F-5G and F-16 to Taiwan and thus the launch customer and the whole reason for the F-5G existing went down the pan.
      Luckily for Taiwan (and less luckily for Northrop) a program to develop another fighter was started in its place with rival General Dynamics (probably to the slight annoyance of Northrop). This fighter developed by AIDC and General Dynamics was to become the F-CK-1 Ching-Kuo and to rub in more salt they even incorporated the APG-67 radar developed for the F-20!

      AIDC F-CK-1 Ching-Kuo (Airliners.net)
      Let’s now take the urine
      In 1983 Reagan allowed funding for Israel to start development of their own fighter in this class that turned into the IAI Lavi. Clearly from Northrop’s point of view the logic that US tax payers should pay for the Lavi while Northrop funded the F-20 by itself seemed a tad off. Eventually this logic may have caught up with the US government when Israel cancelled the program in 1987 influenced by a clear change of attitude from the US.

      IAI Lavi   (Military-Today.com)
      In part 2 Northrop hire Pierre Sprey.....................
      * Yes that is a reference to Back to the Future........I thank you.

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