The F-16A Netz versus the Kfir Block 60

An F-16A Netz. Photo courtesy of merlin824 thru Flickr

Rumors are circling around that the Philippine Air Force (PAF) is considering either the Kfir Block 60 or the F-16A Netz from Israel for possible acquisition. Right off the bat I felt that the F-16A would automatically be the better fighter aircraft, but it would be good to have some sort of data to support this, hence I will try to do it with this blog.

'Aircraft Backgrounds'
The Kfir is based on the Mirage III/5 delta-winged aircraft whose blueprints were stolen by the Mossad (as is now detailed in various spy books and articles¹), and is described as an all-weather, Multi-Role Fighter (MRF) aircraft. It first entered service in 1975 and saw extensive combat duty with the Israeli Air Force (IAF) before finally being retired by the IAF in 1996. A total of 220 Kfirs were built, and currently the air forces of Colombia, Equador and Sri Lanka are still operating the aircraft. 

All Kfirs being sold now are taken from the mothballed stocks of the IAF, but are refurbished and upgraded with advanced avionics plus a 40-year manufacturer's guarantee. The latest version in the market is the "Block 60" equipped with an Active Electronically Scanned Array (AESA) radar, the EL/M-2052.²

The F-16 was made by the American company “General Dynamics”, and first entered service with the United States Air Force (USAF) in 1978. It is described as an all-weather MRF and it is one of the most successful modern aircraft designs as eventually over 4,500 were built and went into service into more than 26 countries worldwide.³

'F-16A Netz'
Israel first received F-16s during the "Peace Marble I" Foreign Military Sales (FMS) program in 1980-1981. 49 F-16A Block 10 were delivered, with these aircraft receiving several unspecified technical modifications unique to their service with the IAF, making them distinct and thus were renamed "Netz" meaning "Falcon" in Hebrew.

Israel wasted no time with their new war toy by using it to bomb the Osirak Nuclear Reactor in Iraq in 1981. The F-16A was used due to the accuracy of its computerized bombing system even when using only conventional munitions. The following year in 1982, the F-16s again saw combat action in the war against Lebanon where they were credited with 44 kills using AIM-9L Sidewinder and Python 3 Short Range Air to Air Missiles (SRAAM) during the short war.

The next batch of F-16A deliveries to Israel was during the "Peace Marble IV" FMS program in 1994 when a combination of 36 Blocks 1, 5 and 10 F-16A were delivered. In total over the years, the "Heyl Ha'Avir" (as the IAF is known in Hebrew) received 85 F-16As, all of which were reportedly upgraded to equal that of the F-16C Barak standards except for the engines, which retained the original GE F100 engine. In July of this year, Israel retired the last two squadrons of its F-16As from frontline service and will instead be relying on their more advanced F-16 models, the F-16C Barak and F-16I Sufa in the frontlines.^{4 5}

The Netz figured prominently in the "Iron Eagle" series of movies as they were all shot in Israel with the help of the Israeli Air Force. As a kid I remember watching the first movie in the series and thinking how wondrous those F-16As looked. Who knew that almost three decades later our Air Force would be considering getting some of those exact same aircraft? Here is a sample scene from the movie, and incidentally, the villains in the movie used the KFIR:

Iron Eagle - Escape by lilmonkey79

'Evaluation Notes'
For the “Maneuverability” and “Payload and Range” sections, the following considerations were made:
- Weights with 100% internal fuel was used to try to simulate the aircraft going into combat with full internal fuel after dropping their External Fuel Tanks.
- The weights of the armaments were not included as the RATIOS and DIFFERENCES BETWEEN BOTH AIRCRAFT will remain the same if they will be armed with the same type and same number of armaments.
- Fuel density of 0.81 kg/l was used to convert fuel capacity to kilograms
- Data for each aircraft was derived from various websites at ^{6 7 8}.

‘Manueverability’
For both aircraft’s maneuvering capability, I am looking at their LIMIT LOAD FACTOR*, WING LOADING* and THRUST TO WEIGHT RATIO.* I would’ve wanted to take a look at more aspects like Stall Speed, Maximum Alpha, etc., but those data are hard to come by for both aircraft. Hence, these should suffice for now. Remember that a lower Wing Loading means the aircraft can turn tighter and vice-versa, and a higher Thrust-to-Weight Ratio means the aircraft can go faster going straight up or straight down and vice-versa.

SUMMARY
- POSITIVE LIMIT LOAD FACTOR: Favors the Netz by 20% as it is rated up to 9G at all flight envelopes while the Kfir is only limited to 7.5G its flight regimes
- WING LOADING: Favors the Kfir with a large 29% lower wing loading compared to the Geagle
- THRUST TO WEIGHT RATIO: 49% advantage for the Netz in terms of TTWR

+++ The Netz has a very impressive TTWR of 1.29 even with a full fuel load, and it will enable it to dictate the fight, choosing to engage and disengage if it wants to during WVR combat by simply "going vertical". Subsequent F-16 models gained more weight and thus became less maneuverable but at the same time improved their ground attack capability, but the F-16A was a pure dogfighter hence even in the IAF they tend to be employed more for close air combat while the Barak and Sufa were used more for ground attack missions.

+++ The Kfir can turn tighter than the F-16A in the horizontal plane, but most of this advantage is lost due to its maximum G limitations. It is typical for most western pre F-15/F-16 fighter aircraft designs to have G limits of only around 7, while the F-16 is stressed for 9Gs through all of its flight envelope.

+++ Overall, the maneuverability advantage lies with the Netz as weighing in the percent differences for and against both fighters, the Netz comes out on top mostly due to its higher TTWR advantage.

A Kfir C12 at a Red Flag Exercise. Photo courtesy of the Nellis AFB Website

‘Payload and Range’
For Range, I am using INTERNAL FUEL FRACTION (INTFF) as a rough indicator how far each aircraft can go based on the internal fuel available to them.

The Kfir's IntFF value was multiplied by 0.87 to reflect the estimated 13% more fuel consumption of its J79 Turbojet Engines as compared to the FA-50's more efficient F404 Turbofan Engines. For more explanation of this, refer to a special section at the bottom page**

SUMMARY
INTFF: Favors the Netz by a large 42%, indicating it can travel 42% farther for the same engine fuel efficiency.
- PAYLOAD: Favors the Kfir slightly as it can carry 13% (763 kg) more load than the Netz.

+++ The Kfir can carry a little bit more load than the Netz, but the Netz is expected to be able to travel a good distance further than the Kfir with slightly less load.

‘Air Combat-related Avionics and Weapons’
Here I am comparing the capability of both aircrafts in terms of Within Visual Range (WVR) and Beyond Visual Range (BVR) air combat thru their Avionics and Weapons available to them. Just some notes, though:
- RCS data are for “clean” aircraft, with no armaments or fuel tanks
- No solid references for the Radar Cross Section (RCS) and detection ranges for the Kfir B60 and its EL/M-2052 radar. RCS is taken from an obscure internet reference, while the EL/M-2052 detection range is just estimated to be 25% higher than the detection range of the EL/M-2032 Radar.
- Other data were taken from this website:^{9 10}

SUMMARY
- WVR COMBAT: Advantage for the Netz because of its Fly By Wire (FBW) system
- BVR COMBAT: Practically even for both aircrafts as the Netz is expected to be able to detect the Kfir at 59 km, or just 3% (2 km) further than the Kfir can detect the Netz which is at 57 km.

+++ The Netz's FBW system means its control reactions are faster which will be more pronounced during successive maneuvers, and it also makes the plane safer as it will be more resistant to stalls and over stressing of the airframe. This will enable the Netz to fly closer to its maximum flight envelopes without exceeding them, while the same thing can't be said of the Kfir with its mechanical flight control system.

+++ The Netz has a more powerful radar than the Kfir, but it also has a higher Radar Cross Section, enabling the Kfir to detect at just about the same time. Of course the Kfir's RCS and radar detection range data are just speculative, and I suspect that the Kfir's EL/M-2052 AESA radar has much better actual performance that stated above, but unless better data becomes available then we will just have to live with these numbers for now.

+++ The Kfir is limited only to the use of the Derby as BVR missile instead of the much longer-ranged AIM-120 AMRAAM. The Netz's use of the Derby is only assumed, while its capability to use the AMRAAM is highly suspect as there are no references saying to that effect. This will impact the Netz negatively when matching up against more capable aircraft than the Kfir.

'AESA Radar'
For me the only advantage the Kfir has that will make it worthwhile to get would be its EL/M-2052 AESA radar. The initial data shows that the AN/APG-66 has a better detection range than the EL/M-2032, but this may not be reliable. If in reality the 2052 has a much better detection range than the APG-66, then that will make the selection between the Netz and the Kfir a little bit more difficult.

AESA radars have a lot of advantages, ranging from improved detection ranges, improved look-down capability, less easy to detect by radar warning receivers, ability to conduct limited electronic warfare, improved maintainability, etc., the list goes on and on.¹¹ Elbit has worked longer towards integrating this radar to the Kfir, and they may be able to do the same to the Netz but no plans have been publicly announced so far and even if they do it will likely take more time and money.

'Parting Shot'
In terms of condition, both the Kfir and Netz I assume would be more or less the same as the Israel Aircraft Industries is in charge of refurbishing/storing both aircraft. Also, the last two squadrons of the Netz in active frontline service were intended to serve up until 2017 until they were shutdown just this year due to budgetary reasons, hence it is likely that those two squadrons are in good shape.

The Netz is superior to the Kfir in terms of overall manueverability and range, but the Kfir has a slight advantage in payload and possibly radar capability. In the end, though, even if the Kfir Block 60's AESA radar proves in reality to be better than the AN/APG-66 of the Netz, I would still tend to lean more towards the Netz because overall it is the better aircraft in more areas, and there is the promise of the AESA radar integration into it anyway in the future despite the additional cost and effort for it. If our air force can afford the Netz, IMHO they should go for it instead of the Kfir Block 60.

After all, the Iron Eagle movies confirm the Netz's superiority by showing it blasting Kfirs out of the sky one after the other. :D

An F-16A Netz on a full afterburner climb. Photo courtesy of xnir thru Flickr

GLOSSARY

• LIMIT LOAD FACTOR = is the maximum amount of stress load on its structure an aircraft is rated for, and is expressed in number of "G". The "stress load" refers to the ratio of the Lift of an aircraft to its weight.
  https://web.archive.org/web/20141104062756/http://en.wikipedia.org/wiki/Load_factor_(aeronautics)
• WING LOADING = is the amount of weight the wing supports during flight, and is expressed in weight per area, or in the metric system, kg/m^2. This is computed by: (Wing Area divided by Weight). https://web.archive.org/web/20140319031516/http://en.wikipedia.org/wiki/Wing_loading
• THRUST TO WEIGHT RATIO = means how much power the aircraft has compared to its weight, and is expressed by a simple number. This is computed by: (The maximum thrust of the aircraft’s engine divided by weight). https://web.archive.org/web/20150324084348/http://en.wikipedia.org/wiki/Thrust_to_weight_ratio
• INTERNAL FUEL FRACTION = is the weight of the internal fuel the aircraft compared to its maximum take-off weight, and is expressed by a simple number. Formula used is: (Maximum internal fuel capacity divided by maximum take off weight). https://web.archive.org/web/20140616134341/http://en.wikipedia.org/wiki/Fuel_fraction

** The F404 engine was developed from the J79 engine. They have the same thrust rating and specific fuel consumption, but the F404 Turbofan engine is 1,470 lbs. lighter than the J79 Turbojet engine, hence the F404 is more efficient as it will need less thrust for the same amount of weight to fly in the air. To reflect this efficiency, the weight savings is divided by the dry thrust or non-afterburning thrust rating (10,900 lbs) of the engine as the aircraft operates most of the time in dry thrust. Values were taken from the book, "An Introduction to Aircraft Performance by Mario Asselin p. 51", http://books.google.com.ph/books?id=kaqvC4e_EKcC&pg=PA51&lpg=PA51&dq=f404+compared+to+j79&source=bl&ots=BJI4siX03v&sig=Xj2mtSqwqJFCDEZQUIXxVvf9UCU&hl=en&sa=X&ei=km1iUoG-H-6eiAfHnYHoDg&ved=0CDkQ6AEwAg#v=onepage&q=f404%20compared%20to%20j79&f=false

SOURCES:

---

1. Israel Aerospace Industries Marketing ‘Pre-Owned’ Kfir Fighter Jets to Eastern Europe, Latin America,
   (https://web.archive.org/web/20131203040240/http://www.algemeiner.com/2013/08/07/israel-aerospace-industries-marketing-pre-owned-kfir-fighter-jets-to-eastern-europe-latin-america/) 
   


2. IAI Kfir,
   (https://web.archive.org/web/20140321003351/http://en.wikipedia.org/wiki/IAI_Kfir) 
   


3. General Dynamics F-16 Fighting Falcon,
   (https://web.archive.org/web/20131213081920/http://en.wikipedia.org/wiki/F-16_Fighting_Falcon) 
   


4. Israel Defense Force/Air Force - IDF/AF,
   (https://web.archive.org/web/20131213113420/http://www.f-16.net/f-16_users_article7.html) 
   


5. GD/L-M F-16A/B Netz in Israeli Service,
   (https://web.archive.org/web/20131016180114/http://www.acig.org/artman/publish/article_276.shtml) 
   


6. General Dynamics (now Lockheed Martin) F-16 Fighting Falcon Multi-Role Fighter,
   (http://www.aerospaceweb.org/aircraft/fighter/f16/) 
   


7. Kfir,
   (https://web.archive.org/web/20160322224649/http://mil.aviations.tripod.com/asia/israel/kfir/info.html) 
   


8. F-21 Kfir, IAI,
   (https://web.archive.org/web/20150628011326/http://www.fighter-planes.com/info/kfir.htm) 
   


9. Fighter Mig-21 Fishbed,
   (https://web.archive.org/web/20140624072432/http://www.enemyforces.net/aircraft/mig21.htm) 
   


10. Situation Awareness in Air Combat,
    (https://web.archive.org/web/20131220225849/http://www.users.globalnet.co.uk/~dheb/2300/Articles/PG/PGSA.htm) 
    


11. THE GREAT RADAR RACE: AESA DEVELOPMENT IN HIGH GEAR,
    (https://web.archive.org/web/20150320045611/http://aviationintel.com/the-great-radar-race-aesa-development-in-high-gear/)