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Data compared between the JAS39C, the JF-17, and the J-10

Length: 14.1m, 14.0m, 16.3m

Wingspan: 8.4m, 8.7m, 9.7m

Height: (excluding landing gear) 3.4m, 3.95m, 4.6m

Empty weight: 5700-6800kg, 6411kg, 9730kg

Max weight: 14000kg, 12700kg, 19277kg

Wing area: 30.2m², 24.4m², 39m²

Internal fuel: 2500kg, 2300kg, 4500kg

Engine thrust dry: 54kN, 49.4kN, 89.17kN

Engine thrust wet: 80.5kN, 84.4kN, 129.4kN

Combat radius: 800km, 1550km with external fuel, 1352km, presumably with external fuel, 2540km, presumably with external fuel

Ferry range: 3500km, 3000km, 3400km

Max speed low alt: M1.2, >M1.0, M1.2

Max speed high alt: M2.0, M1.6-M1.8, M2.2

Climb rate: T/O to 10,000m ~100 sec, T/O to 14,000m in 180sec, N/A, N/A

TWR: 0.97, 0.99, 0.98

Service ceiling: 18,000m, 16,700m, 20,000m

Max G: +9 -3, +8,5 -3, +9 -3

Onset rate: 6-12G/sec, N/A, N/A

Runway length required for operation: 800x9m, N/A, N/A

Take off run: 400m, 500m, <500m

Landing run: 400-500m, 700m, N/A

Turn around time: <10 min, N/A, N/A

MTBF: 7.2h, N/A, N/A

great info.

_________________
I have always believed if done right , armed robbery doesn't have to be a totally unpleasant experience- Brad Pitt as J.D in Thelma and Louise

You don't know that. It depends on the relative RCS values of the aircraft in the relevant relative aspects, the locations over ground/sea and the altitudes of the aircraft and the capabilities of the software processing of the raw data coming from the antennas. It also depends on atmospheric conditions and a thousand other parameters. Raw output power of the antenna is just one parameter going into the equation. The small amount of information in the public domain on the radar and aircraft is not nearly enough to determine who will see who first.

Oryx has a very good point

The information that you have there is an estimate and you don't know what the RCS of the aircraft is that the radar will pick it up at 200 km.

Take for example an F-15, the Gripen will pick it up very much further than 150 km because of the strong return due to the F-15's airframe giving it a large RCS.
Companies will keep the true range of the radar to detect a fighter size target of "X" RCS a secret.

Sourced from Saab Gripen by Aerofax

Not to mention the Gripen can supercruise or more like transcruise (Mach 1.08) which - something even the F/A-18C/D hornet is incapable of doing with two F404J engines, although not hugely important if you can't do it with an air-to-air load, but they don't state in the book if it is with an air-to-air load or not.

I have some free time so I decided to calculated the T/W (Estimates) of the Gripen C and Gripen NG in an air-to-air configuration:

Gripen C

Basic Empty Weight: 14 599 lbs
Internal Fuel: 3000 litres
Specific Weight of Jet A1 at ISA is
6.8 lbs/ 1 USG
1 litre / 1.797 lbs
3000 litres = 5391 lbs

Weight of MBDA Meteor Missile: 185 kg / 407.8552 lbs
4 x MBDA Meteor Missiles: 1631.421 lbs
Weight of IRIS-T Missile: 87.4 kg / 192.684 lbs
2 x IRIS-T Missiles: 385.368 lbs

Average Pilot Weight: +- 80 kg / 176.3698 lbs

Total Weight: 22183.1588 lbs

Thrust Dry: 12473 lbf
Thrust wet: 18105 lbf

Thrust/Weight (Dry): 12473 lbf / 22183.1588 lbs = 0.56
Thrust/Weight (Wet): 18105 lbf / 22183.1588 lbs = 0.82

Gripen NG:

Basic Empty Weight: 15432.36 lbs
Internal Fuel: 4200 litres
Specific Weight of Jet A1 at ISA is
6.8 lbs/ 1 USG
1 litre / 1.797 lbs
4200 litres = 7547.4 lbs

Weight of MBDA Meteor Missile: 185 kg / 407.8552 lbs
4 x MBDA Meteor Missiles: 1631.421 lbs
Weight of IRIS-T Missile: 87.4 kg / 192.684 lbs
2 x IRIS-T Missiles: 385.368 lbs

Average Pilot Weight: +- 80 kg / 176.3698 lbs

Total Weight: 25172.9188 lbs

Thrust Dry: 14000 lbf
Thrust wet: 22000 lbf

Thrust/Weight (Dry): 14000 lbf / 25172.9188 lbs = 0.56
Thrust/Weight (Wet): 22000 lbf / 25172.9188 lbs = 0.87

If anyone sees anything wrong please let me know, this was the basic estimation of the T/W at Standard Temperature (+15), my best guess would be that the ratio would decrease with a lower temperature because Jet A1's density increase with a decrease in temperature.

Wow Robban - excellent diagrams mate! Tahnks for that. The one with the Gripen included really adds perspective.
Very very interesting. They say the J-10 was not influenced by the Lavi however looking at those my doubts
are renewed.

Thanks, 60sqdnSAAF!




I'm a bit puzzled when it comes to the empty weight of the Gripen. Some sources say 5700kg, other say 6622kg. Which one is the most correct weight? That is anyones guess.

Just an example. The JA37 Viggen, has an official empty weight of 12.200kg, whereas its real empty weight is close to 10.000kg. Fully fueled with a full drop tank it weighed 16.400kg. Internal fuel capacity was 7000 liters, + 1100 liters in the external under belly drop tank. 8100 liters =6600kg. 10.000 + 6600 = 16.600kg.

Gripens normal take off weight is ~9000kg. A Gripen normally flies with no external stores apart from a belly drop tank. Full internal fuel + one full drop tank = 4100 liters, ~3300kg. 5700 + 3300 = 9000kg. I'm just speculating, but it's not totally off is it?

In 2007 an engineer in the J-10 project gave an interview (http://www.szccf.com.cn/movie_content.asp?id=300 and http://www.szccf.com.cn/movie_content.asp?id=301) and commented saying the J-10 has a radar with a range of 150km. He did not say the target RCS but then went on to compare with the F-22's 170km. Apparently the 170km for the F-22 is against a 1 sqm target. If you assume he meant a 1 sqm target, then the J-10 will have 224km range on a 5sqm target. The Gripen has 120km for the same size. If we are consevative and assume the J-10 radar spec he gave is for 3sqm, them it will have 170km on 5 sqm. In either case, the J-10 has more range. We don't know about jamming and anti-jamming capabilities. However concerning general quality, the FC-1 (JF-17) radar, the KLJ-7, is a miniturised version of the radar on the J-10. Now, the KLJ-7 beat French, Italian, British, Russian and Israeli radars for the PAF order = I am sure that says a lot about its capabilities and quality.

_________________
In God I trust, everyone else bring your data!

who is not estimating on this forum? guys like robban are even puzzled because they dont know the exact empty weight of the gripen because sources differ.



ceteris paribus. holding other things constant orxy

_________________
I have always believed if done right , armed robbery doesn't have to be a totally unpleasant experience- Brad Pitt as J.D in Thelma and Louise

I know what you mean Robban, some sources state the Gripen C T/W is 0.98 and the Gripen NG is 1.12, but then the Gripen empty weight is wrong or the Gripen will have no external load and not be fully fueled. So something is missing...



So I guess you might be wrong since we are all making estimations.

It doesn't work like that with radar and fighters. You have two aircraft with different radars and different RCS distributions. One might have a more powerful radar, but possibly also a higher RCS from a given aspect. So, you get the situation that you have these two aircraft pointing directly at each other, but the one with the weaker radar sees the other one first. Change the aspects a little - let's say a 30 degree offset, which may just happen to be an aspect where the smaller aircraft has a RCS spike, and suddenly the aircraft with the more powerful radar sees the other one first. Change altitude and the one with the better processing software and filters now sees the other one first due to the way ground reflections are processed. Fly low-level over the ocean and again the situation may change due to the way reflections over water work. Change the sea state and again a different result. Radar technology just simply is not as straightforward as you seem to think. What manufacturers publish in the public domain give you very limited information and not nearly enough to determine who will see whom first, regardless of whether "everything else" is equal or not.

got it

_________________
I have always believed if done right , armed robbery doesn't have to be a totally unpleasant experience- Brad Pitt as J.D in Thelma and Louise

A 39 Gripen A have a best RCS of only 0.1 sqm which must be one of the best numbers for the 4.5 Gen figthers.
The figures for Gripen C are not available in public but they are constantly working on improvements in that particual area, the same is true for the Gripen NG.

//JG

Great comparisons and artwork Robban.

Thanks for making the effort for this forum (and to all the other contributors for their explanations and research).

You're very welcome Dean!