Saab JAS 39 Gripen Info # 2

[signatory]

Link to first thread and the first post with many links to Gripen info such as info on range, speed, rcs, service, radar, airframe, EW package etc.

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Quick summary on the different main models:

Gripen NG is 3% heavier than JAS 39C but comes with over 22% more engine thrust.

Gripen NG Range
Range is increased an average of 40% over the JAS 39C as both the internal and external fuel capability is expanded.

Combat radius: 1,300 Km + 30 minutes on station with A2A weapons.
Range (one-way): 2,500 Km on internal fuel
Ferry range (one-way): 4,075 Km with external fuel
Combat Radius estimate: 1,800 km with A2A weapons

One drop tank (450 Gal) gives the Gripen NG an extra range of approximately 1000 km.

AESA

The aircraft has been in the workshop since early April being readied for its second test phase. This will introduce missile approach warners and satellite communications equipment and, from later this year, an active electronically scanned array (AESA) radar: Selex Galileo's Vixen 1000E/ES05 Raven.

Saab rolled out the Demo with an agreement to use an AESA demonstrator provided by Thales, but their relationship quickly crumbled. Thales says it withdrew the technology as it was already under contract for the Rafale, but Kemp gives a different explanation. "The radar wasn't good enough for what we needed to do," he says. "The Selex radar is seriously outstanding. When you brief people on the capabilities they are astonished."

Bob Mason, Selex Galileo's executive vice-president, radar and advanced targeting, says the Vixen 1000E's advantage comes from the use of a swashplate mounting, which enables the active array to be rotated by +/-100°. This beats a fixed AESA during beyond visual-range and off-boresight missile firings, and while acquiring synthetic aperture radar imagery, he says. "We will be delivering a prototype this year for them to fly, and then will upgrade it over the next 18 months."

source
Source 2



Thanks for looking.

[signatory]

Gripen International talks about their offers to these countries:

Gripen NG for Brazil

Gripen NG for India

[MM11]

Thanks for this 3nd part Signatory. I ever thought fuel load of the A-D modells would be 2270 kg and that by adding 40% you would reach 3178 kg, just out of the calculation? But the 40% might be a rough indication only and if they say so it should be correct. Is there a link available where Saab states 3500 kg?

[signatory]

Thanks for this 3nd part Signatory. I ever thought fuel load of the A-D modells would be 2270 kg and that by adding 40% you would reach 3178 kg, just out of the calculation? But the 40% might be a rough indication only and if they say so it should be correct. Is there a link available where Saab states 3500 kg?

Fuel on 39C and A is 3000 L i.e 2400 Kg.

2270 is misinformation if you will. Since the A model had a peace and war setting on the fuel system. That was removed on the C and it's now always filled up to the max.

Link is on the old page but I'll post it again:



It's from handout Aero india 09 information.

The MTOW also grew a bit more since the first presentations on the NG. Since they actually built the Demonstrator and by the looks of it could confirm a bit more positive numbers on MTOW and fuel.

[MM11]

Thanks for the clarification.

[swerve]

The similarity of some of the numbers to Mirage 2000 is striking. Gripen NG is a little smaller, a little lighter when empty, but has the same maximum T/O weight, much the same external load, & a little more internal fuel.

[H_K]

Yes, they are very similar in terms of specs. In fact, the main thing that explains the differences in empty weight and internal fuel is the more modern F414 engine on the Gripen. It is about 400kg lighter than the Mirage 2000's M53-P2 (for approx. the same thrust) and probably also takes up less volume.

[MP703]

The similarity of some of the numbers to Mirage 2000 is striking.

Funny, I was thinking the same thing. Still, a lot of people refers to the M2K as a medium weight fighter rather than a small and light fighter.

If the 3,5t of internal fuel data is correct I guess that means an increase of fuel capacity of more than 45%?

About engine growth, I wonder if this would mean the development of a RM something from the existing F414G or adopting the new F414 EDE? It would also be interesting to know how much weight could be reduced?

[signatory]

Funny, I was thinking the same thing. Still, a lot of people refers to the M2K as a medium weight fighter rather than a small and light fighter.

If the 3,5t of internal fuel data is correct I guess that means an increase of fuel capacity of more than 45%?

About engine growth, I wonder if this would mean the development of a RM something from the existing F414G or adopting the new F414 EDE? It would also be interesting to know how much weight could be reduced?

For weight reduction, the main effects could come from increased use of light weight material. "Only" about 30% of the Gripen's structure is composite today and they have several studies out on what parts could be replaced. One section we know is looked at is the air channel to engine. Volvo Aero is also investing highly in research on new engine components for reducing weight on aircraft engines but I've not seen anything solid on what that could mean for the Gripen program.

Quick babelfish from Saab job offering on a thesis job how to hook up a new air channel in composite:

Work includes both improvements to existing airframe as the further development of the aircraft to meet future requirements. The thesis work consists of investigating attachment possibilities for a new internal air channel in composit to 39 Gripen and to develop a design proposal.

In order to develop the aircraft against future requirements, and reduce weight investigate the possibilities of having a load bearing air channel in composite.

http://vakanser.se/jobb/exjobb+luftk...jas+39+gripen/

About engine, well there's EDE... but there's other engine improvement programs to the RM12 and F414 that probably could be applied to the F414G. Even small steps can be important...

[MM11]

BTW wgat about the Saab IR-Otis? I've read about it many years ago, but found nothing more up to date about it. Is it still under development and does the Flygvapnet intends to introduce such a system? I see an IR-housing in all those graphics for the NG version, but nothing concrete is given.

[21Ankush]

The similarity of some of the numbers to Mirage 2000 is striking. Gripen NG is a little smaller, a little lighter when empty, but has the same maximum T/O weight, much the same external load, & a little more internal fuel.

which would make it the perfect Mirage-2000 replacement for the originally intended role of the MRCA, wouldn't it ?

of course, the Gripen is more nimble than the Mirage, with more modern avionics, airframe, weapons and a definite upgrade path that would for sure be backed by Sweden, unlike the Mirage, which would've had to be upgraded by India alone.

one question- with the same wing dimensions, the wing loading of the NG is definitely higher than C/D variants. how much of an effect does that have on the agility ? F-16s have grown heavier over the years and also grown to be less nimble than earlier Block variants, is the Gripen going down the same path?

[MM11]

one question- with the same wing dimensions, the wing loading of the NG is definitely higher than C/D variants. how much of an effect does that have on the agility ? F-16s have grown heavier over the years and also grown to be less nimble than earlier Block variants, is the Gripen going down the same path?

As long as the wing area remains the same yes, but unlike the F-16 even the latest NG isn't much heavier than the first A model, so the difference more more neglicable, something which isn't the case of the F-16 which has grown by ~25-50% in empty weight in the later versions. The difference between the JAS 39A and the NG model is about 6%.

[Snow Monkey]

which would make it the perfect Mirage-2000 replacement for the originally intended role of the MRCA, wouldn't it ?[

There's certainly some irony there...
Though Saab probably isn't over-stressing that point, lest it be taken as a back-hand swipe at the competency of India's military procurement

As for agility, I think the minor +/-10% differences really aren't so signifigant any more with HMCS and agile missiles...

[swerve]

one question- with the same wing dimensions, the wing loading of the NG is definitely higher than C/D variants. how much of an effect does that have on the agility ? F-16s have grown heavier over the years and also grown to be less nimble than earlier Block variants, is the Gripen going down the same path?

The difference is that the empty weight of the F-16 has grown considerably, in line with its increase in maximum take-off weight, but the Gripen empty weight has grown very little. Only its maximum T/O weight has gone up significantly.

[MP703]

of course, the Gripen is more nimble than the Mirage

But not much. Yet, I never heard anyone call the M2K small?

one question- with the same wing dimensions, the wing loading of the NG is definitely higher than C/D variants. how much of an effect does that have on the agility ?

Apparantly, the Gripen NG is 200 kg heavier than the Gripen C/D. As Signatory commented earlier in this thread, SAAB is taking measures to reduce the weight of the design. If this work results in a reduction of more than 200 kg (pretty realistic IMHO), I would assume that the wing loading of the NG will be even less than the C/D.

[21Ankush]

As long as the wing area remains the same yes, but unlike the F-16 even the latest NG isn't much heavier than the first A model, so the difference more more neglicable, something which isn't the case of the F-16 which has grown by ~25-50% in empty weight in the later versions. The difference between the JAS 39A and the NG model is about 6%.

its not the empty weight difference alone. the internal fuel has gone up by nearly 36%. that means that an increase in all-up weight of 36%, and that would adversely affect the wing loading.

[21Ankush]

But not much. Yet, I never heard anyone call the M2K small?



Apparantly, the Gripen NG is 200 kg heavier than the Gripen C/D. As Signatory commented earlier in this thread, SAAB is taking measures to reduce the weight of the design. If this work results in a reduction of more than 200 kg (pretty realistic IMHO), I would assume that the wing loading of the NG will be even less than the C/D.

its not going to fly with no fuel in, is it ? the purpose of relocating the landing gear was to free up space for additional fuel, which means increased all-up weight. when it does fly with the increased fuel weight, the wing loading will be higher.

[Rogerout]

its not the empty weight difference alone. the internal fuel has gone up by nearly 36%. that means that an increase in all-up weight of 36%, and that would adversely affect the wing loading.

You could say that the more fuel can be burnt by using the afterburner, wich adds agility of another kind. But if you use the extra fuel for extending range to the combat area, you need to preserve more fuel for the flight home so you have a point.

On the other hand the extra thrust of the F414 also adds agility in a way that offsets the higher wingloading. For comparison consider that Gripen NG has a larger wing area than F-16 and an empty weight that is about the same as the original F-16A.

[signatory]

Since we're on that topic... the Danish Officer's Magazine last year quoted Saab at the roll out on the Gripen NG weight being "under 7000 Kg"

Source (Danish)

From the looks of it, so far all the preliminary numbers Saab presented in the 1-2 years before they built and flown the Demonstrator has either been confirmed or slightly improved since then.. Most recently I heard the Demonstrator engine is installed on 22,500lbs as opposed to 22,000 and in most Saab presentations one could see a ">22,000".. all small but nice steps. Steps towards a NG...

Saab also recently mentioned that one 450Gal drop tank adds about 1000 Km range to the aircraft.. so internal fuel (2500km) + one such tank gives the jet a range of 3500 Km. And I think for counter air one centreline tank and keeping wings free for missiles would be the right choice for this type of aircraft..

[insomnia.delhi]

Thanks for looking.

nice collection, thank you for posting all that

Does the R Swedish Air Foce have any requirements for the Gripen NG?

[signatory]

nice collection, thank you for posting all that

Does the R Swedish Air Foce have any requirements for the Gripen NG?

Generally speaking they can do their job without NG as a whole, but want in this order:

1. The NG avionics
2. The engine
3. The new airframe with more fuel.

1) they will get this over time as normal upgrades to C/D

2) + 3) more unsure but has a intended SwAF target 2018+ or sooner if a export customer is found...

It also depends on the political climate...

[Rogerout]

Saab also recently mentioned that one 450Gal drop tank adds about 1000 Km range to the aircraft.. so internal fuel (2500km) + one such tank gives the jet a range of 3500 Km. And I think for counter air one centreline tank and keeping wings free for missiles would be the right choice for this type of aircraft..

Can really a 450Gal tank be carried centreline? Sounds a bit heavy.

[signatory]

Can really a 450Gal tank be carried centreline? Sounds a bit heavy.

As opposed to the 4000 lbs of LGBs on the sister pylons?



The range example Saab gave was with one 450gal tank and I seriously doubt they intended it for a assymetrical under-wing layout. Especially as it was given next to a package offering that contained 85 such tanks for 85 Gripen NG to the Netherlands.

[Rogerout]

Thanks Signatory, I believe I read that the max load for the centre pylon on Gripen C was 1100 kg. I cant find any reference right now, but if I'm right it seems that the centre pylon on the NG will be strengthened significantly. Nice. Would be interesting to know the max load on the individual pylons.

[insomnia.delhi]

Generally speaking they can do their job without NG as a whole, but want in this order:

1. The NG avionics
2. The engine
3. The new airframe with more fuel.

1) they will get this over time as normal upgrades to C/D

2) + 3) more unsure but has a intended SwAF target 2018+ or sooner if a export customer is found...

It also depends on the political climate...

Is there any information on SAAB following up on its line of fighters in near future (as in a new fighter project)? Or will that be considered post a 2018ish time-frame?

[uss novice]

Well, the NG is certainly an amazing step forward. The ability to integrate the Meteor is another fabulous plus point. The only negatives that I can see from a MRCA point of view:

1) Single engine (less safety, something the IAF seems to love in strike roles).

2) Very close to the M2k, but none of its commonality with the existing fleet, which, I feel was probably the main reason the IAF wanted the M2ks in the first place - quick replacement.

3) What next? Upgrade path esp. in terms of airframe seems limited. I can see CFTs and a more powerful engine in 20 years - so certainly better than the F-16, but the small airframe might have limitations.

As far as the comparison with the C version goes, it is going to have better performance under all circumstances the C would fly in. The wingloading will become an issue only when the NG starts getting into payload specs that the C simply cannot hope to achieve. Anyway isnt high wingloading preferred for strikers (F-18, F-16, Jags etc)?

USS.

[Loke]

Well, the NG is certainly an amazing step forward. The ability to integrate the Meteor is another fabulous plus point. The only negatives that I can see from a MRCA point of view:

1) Single engine (less safety, something the IAF seems to love in strike roles).

If you look at the number of incidents with F-16 (after they fixed some issues in the early days) the safety is surprisingly good with one-engine fighters. Check the "modern" stats (last 25 years or so) and you will see that single-engine a/c are pretty safe these days.

Even the USN has accepted this and is shifting to F-35.

L

[Scorpion82]

If you look at the number of incidents with F-16 (after they fixed some issues in the early days) the safety is surprisingly good with one-engine fighters. Check the "modern" stats (last 25 years or so) and you will see that single-engine a/c are pretty safe these days.

Even the USN has accepted this and is shifting to F-35.

L

There are still a lot of engine related loses in comparison to twin engined designs such as the F-15. The USN had not much choices at all and accepted the F-35 as there was no other way... Though you are right that single engine fighters are safer today than they were in the past.

[H_K]

In the past 5 years, F-16s have been lost at a rate 5x higher than F-15s due to engine related causes (one F-16 lost every 184,000 flight hours, versus one F-15 lost every 880,000 flight hours). The difference used to be over 10x higher, but the F-16's engine has become more reliable. (for details, search for "engine related destroyed aircraft statistics" at www.afsc.af.mil)

So for a fleet of 100 fighters with service lives of 8,000 hours, you can expect to lose 4-5 single-engined aircraft due to engine-related causes, but only 1 twin-engined aircraft. However, this overstates the single-engined aircraft's reliability, because you'd also have to factor in birdstrikes, which are a bigger problem for single-engined aircraft...

[obligatory]

I think the range of Gripen NG is superb, -you just can't ask for more.
The sad part is that the NG incarnation wasn't made from start.