No plans for EJ200 Gripen

[Crazypilot]

Hello, I am a new one

2 days ago I had sent a message to Volvo Aero. This was the message:

Dear Volvo Aero,

I have been reading for 2 years or so that SAAB Aerospace is interested in to fitting the Eurojet EJ200 engine on the JAS-39 Gripen. Volvo Aero stated that only few changes in the geometry of the air intakes are necessary for the installation. But there not any news concerning cooperation between Volvo Aero and Eurojet Turbo GmbH. Are you going to proceed with this modification?

I look forward to hearing from you.

Sincerely,
Athanasios Ioannidis,
Student

Today I received from Volvo Flygmotor this answer:

Dear Athanasios,
Β
I checked with our military engines department and there are no plans to replace the RM12 with the EJ200. A change of engine won't give any significant increases in performance.Β It would also demand a major re-construction. The EJ200 is not installed in or adapted forΒ single engine aircraft.Β Β
Β
Best regards,
Β
Geryll AlsΓ©n
Corporate communications

Thus, there are still no plans for fitting a new engine. What do you believe?

[Cliff Barnes]

Well the major question here is - who is going to fund a new engine? Swedish air force is not in the position to throw in billions of euros for a new engine at this moment. Saab could do it, but is it worth the price? Considering the tenders they were in the last couple of years, I'm not so very sure that they would have won those that they lost (Poland, Austria, Chile) by just getting a more powerful (non-american) engine.

regards,
Cliff

[eagle]

The Gripens twr is not that great with the rm12 so the ej200 would be a good option imho. The ej200 is a much newer design and theres still a lot of potential in it (120kn+) whereas the rm12 is at the end of its life cycle.
A Gripen with 12 tons of thrust would be a real monster.

[glitter]

I read on the french magazine air & cosmos that the SNECMA M88-3 (the higher thrust version, not the economic one) could be fit in the Grippen.

Knowing that tat engine is smaller than the EJ200 perhaps it's possible without major change.

RM 12
total length 4.04 m/159 in
max.diameter 0.884 m/34.8 in
inlet diameter 0.709 m/37.9 in
engine dry weight 1055 kg/2325 lbs

EJ200
Length, m (ft,in) ~ 4.0 (~ 13'2")
Diameter, m (ft,in) ~ 0.85 (~ 2'9")

M88
Length : 139 in (3,538 mm)
Inlet diameter : 27.5 in (696 mm)
Weight : 897 kg

[Cliff Barnes]

Originally Posted by eagle

The Gripens twr is not that great with the rm12 so the ej200 would be a good option imho. The ej200 is a much newer design and theres still a lot of potential in it (120kn+) whereas the rm12 is at the end of its life cycle.
A Gripen with 12 tons of thrust would be a real monster.

Theres two sides of each coin, so the RM12 (GE 412) might be much weaker than EJ200 but it's reliability has been proven to be very good. And that tends to be quite important for single engine fighters.

Today I would say that the GE414 might be the easier choice to get a better engine. It fits without any greater fuzz and it's proven. The EJ200 have the upper hand by being european (read politics on export) and being a newer design. But I wouldn't consider it mature enough for a single engine fighter at present.

As a sidenote, thrust-to-weight-ratio is just one of all the parameters that affects a fighters performance. There are other factors of which we have no clue about that are just as important, drag and grade of instability to take a couple of examples. Therfore, it's quite pointless to compare fighters by comparing twr figures.

regards,
Cliff

[OPIT]

From a mechanical point of view, the M88 is not a good fit because it's significantly shorter and lighter. That would require a spacer in front of the inlet, or a new (longer) afterburner section, as well as a careful management of weight to not mess with the center of gravity. However, M88 airflow should be close to that of the RM12, thus saving the need to redesign the air intakes. All in all, some M88 derivative could do the job quite easily.

The EJ200 looks similar to the RM12 (length, diameter and weight), but a higher air flow might trigger the needs to redesign the air intakes, which is costly and time consuming.

Neither the EJ200 nor the M88 are used in single engine aircrafts, nor designed to do so, and neither provide any significant benefits over the RM12.

[Jackonicko]

The chief problem is cost. It would require massive investment to clear EJ200 for single-engined operation and even greater investment to integrate the new engine in Gripen. The result would be a small but useful improvement in performance. My understanding is that re-engining could be an option were India to place a significant order, since their requirement is potentially large enough to make it worthwhile and cost effective, and since F404/Kaveri is not as highly regarded as it once was, and since India would like to place less reliance on the USA, not more.

But that's very much the talk I've heard at dinners and in bars at the end of busy days at Paris and Farnborough, and how far any formal proposals have got is another story entirely.

[glitter]

Originally Posted by OPIT

From a mechanical point of view, the M88 is not a good fit because it's significantly shorter and lighter.

I have a hard time to imagine that a bigger and heavier engine would be a best solution.

Originally Posted by OPIT

as well as a careful management of weight to not mess with the center of gravity.

FWB are made for that.

Originally Posted by OPIT

Neither the EJ200 nor the M88 are used in single engine aircrafts, nor designed to do so, and neither provide any significant benefits over the RM12.

That's raelly the first time I heard that for fighters engines.
Not design for single engine arcrafts ??? I supposed the GE-404 hasn't been neither

[OPIT]

Originally Posted by glitter

I have a hard time to imagine that a bigger and heavier engine would be a best solution.

Bigger and heavier ? Please check your datas twice...
EJ200 and RM12 have the about the same length, inlet diameter, maximum diameter and weight.

Originally Posted by glitter

FWB are made for that.

Well, sort of. FBW systems are optimized as to not under/over-react to any aircraft movement. Doing otherwise either decrease performance (drag, instability) or lead to serious problems (crashes). If you move the aircraft's center of gravity, you're likely to have to rewrite FBW software and test the entire flight envelope again.

That's raelly the first time I heard that for fighters engines.
Not design for single engine arcrafts ??? I supposed the GE-404 hasn't been neither

It's never too late to learn something
On twin engine aircrafts, you can afford to loose one engine (failure) to some extent. This allows you to push the limits a bit further. On single engine aircrafts, you're likely to crash soon whenever the engine fails (backup systems can't provide power for too long). This simple fact has many implications on engines design.

BTW, the RM12 is a F404 derivative designed and built to fit a single engine aircraft : the Gripen. Beside, you suppose wrong :
"In the early 1980s, Northrop installed the F404 in its F-5G single-engine fighter later designated the F-20."
http://www.geae.com/engines/military/f404/

[Crazypilot]

Sorry, but ITP of Spain has ALREADY designed a thrust vectoring version of JAS-39 Gripen.
In a few months the Gripen is going to participate to a new aircraft contest for the Hellenic Air Force. Though we know that Typhoon will be the choice, an EJ200-engined Gripen would be also sellected (only if Gripen International provides high offsets) for Greece cannot maintain twin-engined aircrafts ONLY.Because JSF is American-led programme, which means restrictions over technology transfer to Greece (see balance of powers in the Aegean Airspace), thus we have only the Gripen alternative. And because a corporation must make profits, it is necessary to make this investment.
Here is the link of the ITP's Financial Report.

http://66.249.93.104/search?q=cache:...200+2005&hl=el

You will find it on page 27.

[AirToAirCombat]

How many more new build Gripens are going to be built in time to take advantage of a new engine?

Are you proposing that existing Gripens can be upgraded? Assuming that current Gripen airframes can be upgraded to accept a EJ200 is a big assumption.

[eagle]

Originally Posted by Cliff Barnes

Theres two sides of each coin, so the RM12 (GE 412) might be much weaker than EJ200 but it's reliability has been proven to be very good. And that tends to be quite important for single engine fighters.

Sure the older engine is more proven. The risk is always higher the newer the tech is. The ej200 on the other hand didnt have any problems too (except one crash).

Originally Posted by Cliff Barnes

Today I would say that the GE414 might be the easier choice to get a better engine. It fits without any greater fuzz and it's proven. The EJ200 have the upper hand by being european (read politics on export) and being a newer design. But I wouldn't consider it mature enough for a single engine fighter at present.

The ge414 sounds interesting, and volvo is involded too. Afaik, it has the same diameter as the rm12 so it might fit rel. easy.

Originally Posted by Cliff Barnes

As a sidenote, thrust-to-weight-ratio is just one of all the parameters that affects a fighters performance. There are other factors of which we have no clue about that are just as important, drag and grade of instability to take a couple of examples. Therfore, it's quite pointless to compare fighters by comparing twr figures.

regards,
Cliff

Yeah but you can never have enough thrust. Compared to the newest fighters around the Gripen does look somewhat weak. even though power ist just one factor.

[eagle]

Originally Posted by OPIT

Bigger and heavier ? Please check your datas twice...
EJ200 and RM12 have the about the same length, inlet diameter, maximum diameter and weight.

If i remember correctly, the ef consortium even considered the f404 as an option for the Eurofighter. So its no surprise they share the same dimensions.

[Crazypilot]

Here is a link of a Slovakian guy showing a scale model of a tailless Stealth Gripen

http://www.hitechweb.szm.sk/stealth4f.htm

And YES newer versions will come after 2010, since SAAB participates on the Dassault-led NEURON UCAV.

[glitter]

Originally Posted by OPIT

Bigger and heavier ? Please check your datas twice...
EJ200 and RM12 have the about the same length, inlet diameter, maximum diameter and weight.

Ouch, my bad.
I always thought it was the EF200 that was slightly bigger than the RM12 when it's the opposite.
About the weight, I find it hard to believe that saving a good 100Kg wouldn't be seen as a very good news.

Originally Posted by OPIT

It's never too late to learn something
On twin engine aircrafts, you can afford to loose one engine (failure) to some extent. This allows you to push the limits a bit further.

What's "a bit further" ?
The M88 has been proposed for single engine without modification (LCA, "super' grippen, T 50 and as an upgrade for mirage 2000 in the future M88-4 flavor)

Originally Posted by OPIT

This simple fact has many implications on engines design.

Are you sure it's a reality for ailiner engine only ?

Originally Posted by OPIT

BTW, the RM12 is a F404 derivative designed and built to fit a single engine aircraft : the Gripen. Beside, you suppose wrong :
"In the early 1980s, Northrop installed the F404 in its F-5G single-engine fighter later designated the F-20."

THe RM12 built to fit a single engine ? No, really ?
Show me what technological choice on EJ200 or M88 make them not suitable for the moment to a single engine aicraft .

[eagle]

The RM12 has been modified to better withstand bird strikes.

[turboshaft]

Glitter - the RM12 benefits from the work already undertaken on the F404 for single-engine apps. The EJ would require accessory and FADEC mods (& recert), which means funding. As Jacko has already said, at the end of the day it all comes down to the mighty dollar (or krona).

Crazypilot - it's my understanding that the ITP TVC effort is now focused exclusively on Eurofighter (for the fabled Tranche 3...).

[PILOTGHT]

Originally Posted by glitter

Ouch, my bad.
I always thought it was the EF200 that was slightly bigger than the RM12 when it's the opposite.
About the weight, I find it hard to believe that saving a good 100Kg wouldn't be seen as a very good news.



What's "a bit further" ?
The M88 has been proposed for single engine without modification (LCA, "super' grippen, T 50 and as an upgrade for mirage 2000 in the future M88-4 flavor)



Are you sure it's a reality for ailiner engine only ?



THe RM12 built to fit a single engine ? No, really ?
Show me what technological choice on EJ200 or M88 make them not suitable for the moment to a single engine aicraft .

You forget the Mako, and i'm quite doubting about M2k M-88 purpose, it's not dassault or any french supplier, only speculations of uninformed jornalists:

[glitter]

For mirage 2000 engine, the M53 P3 is the future main upgrade of the series and I don't know what can be possible next. But it must be said that some nation will use their mirage for decade so that another step can be think of.
I read once about a possible M88 upgrade.
According to this link http://www.network54.com/Forum/threa...&lp=1124572557
posted by fonk, it's from the CEO of SNECMA.

[PhantomII]

I thought the MAKO was pretty much a dead project....

[OPIT]

Originally Posted by glitter

For mirage 2000 engine, the M53 P3 is the future main upgrade of the series and I don't know what can be possible next. But it must be said that some nation will use their mirage for decade so that another step can be think of.
I read once about a possible M88 upgrade. (...)

M53 upgrade used to be the M53-P20, which is abandonned (AFAIK). The M53 serie is rather outdated now, for it was designed in the late 60'.
So if SNECMA proposes any new engine, it has to be a M88 derivative (mainly built from M88 compressors, combustion chamber and turbines) and not the M88-2/3/4 as we know it. However, it doesn't make much sense to change the engine on existing aircrafts, unless savings on the operational costs offset the price of the new engine. I guess SNECMA offer is targetted toward new customers, who will then have to pay for its development and integration.

[Crazypilot]

Turboshaft: The US Navy is also interested on EJ200 TVC

http://pubs.nrc-cnrc.gc.ca/casj/casj48/q02-020.pdf

Wow... European engine to US aircraft!

[glitter]

Originally Posted by OPIT

M53 upgrade used to be the M53-P20, which is abandonned (AFAIK). The M53 serie is rather outdated now, for it was designed in the late 60'.

So if SNECMA proposes any new engine, it has to be a M88 derivative (mainly built from M88 compressors, combustion chamber and turbines) and not the M88-2/3/4 as we know it.

THe PX is supposed to use some technologies from the M88 IIRC, but nothing really important for the architecture of the engine.

About the "M88 derivate" I must say that I don't understand.
THe M88-4 is still only in engineers mind since nothing has been decided now (for what I know). So what can prevent SNECMA to make it fit properly into a mirage 2000 ?

[OPIT]

Originally Posted by glitter

THe PX is supposed to use some technologies from the M88 IIRC, but nothing really important for the architecture of the engine.

That's it. The design being quite old, growth potential is quite limited and most improvements would focus on economical benefits (operational costs reduction). Upgrading the M53 is the easiest and safest route, and a low cost solution.

Originally Posted by glitter

About the "M88 derivate" I must say that I don't understand.
THe M88-4 is still only in engineers mind since nothing has been decided now (for what I know). So what can prevent SNECMA to make it fit properly into a mirage 2000 ?

Cost. SNECMA would have to design a larger fan stage, a larger compressor (to keep the bypass ratio), most probably a larger turbine, a larger and much longer afterburner section, and a new casing to make the engine fit nicely into the airframe. That's basically a new engine based upon M88 technology, hence a M88 derivative. Then, potential customers would have to scrap their M53 and buy this new engine (upgrade) or buy new aircrafts fitted with this engine.
By now, all M88 upgrades are targetted to the Rafale (same engine shape, length and diameter).
On the same topic :
http://www.mirage-jet.com/Propulsion...s/upgrades.htm

[franc]

Now, if this time Norwegian chose Gripen as their next generation fighter, then ask EJ-200 to equip JAS-39, I think there is no problem

[swerve]

Originally Posted by Cliff Barnes

Theres two sides of each coin, so the RM12 (GE 412) might be much weaker than EJ200 but it's reliability has been proven to be very good. And that tends to be quite important for single engine fighters.

Today I would say that the GE414 might be the easier choice to get a better engine. It fits without any greater fuzz and it's proven. ...

regards,
Cliff

Doesn't it need more physical changes to the airframe than the EJ200?

[Schorsch]

Originally Posted by eagle

The Gripens twr is not that great with the rm12 so the ej200 would be a good option imho. The ej200 is a much newer design and theres still a lot of potential in it (120kn+) whereas the rm12 is at the end of its life cycle.
A Gripen with 12 tons of thrust would be a real monster.

Like always some people in this forum tend to focus on maniverability first and forget other things about it. The fact that the Gripen is able to achieve Mach 2 with a lower TWR than some American designs (incl. F-18) shows the aerodynamic benefits of the design. The TWR is surely not the best in the world, but it is sufficient. There is no need for "super-manouverability", so designers re-think.
Fast is that the Gripen with its current engine is a marvelous machine: very low weight, high capability, true multi-role, easy maintenance and handling, very competitive flight performance. It is not the best performer, but for the customers in question it is not of importance. When you see how much some designs sacrifice for the extra deg/sec, you doubt that it was worth it.

Unfortunately, the Gripen (like the M2000) lacks the backing of a powerful nation to achieve sales in the market. Instead air forces buy crappy used F-16 or horribly expensive new F-16C.

[eagle]

Originally Posted by Schorsch

Like always some people in this forum tend to focus on maniverability first and forget other things about it. The fact that the Gripen is able to achieve Mach 2 with a lower TWR than some American designs (incl. F-18) shows the aerodynamic benefits of the design. The TWR is surely not the best in the world, but it is sufficient. There is no need for "super-manouverability", so designers re-think.
Fast is that the Gripen with its current engine is a marvelous machine: very low weight, high capability, true multi-role, easy maintenance and handling, very competitive flight performance. It is not the best performer, but for the customers in question it is not of importance. When you see how much some designs sacrifice for the extra deg/sec, you doubt that it was worth it.

Unfortunately, the Gripen (like the M2000) lacks the backing of a powerful nation to achieve sales in the market. Instead air forces buy crappy used F-16 or horribly expensive new F-16C.

I know the Gripen is fine as it is now. And manouverability is excellent anyway. But more thrust would not hurt, it never does.
Of course, it depends if a customer is willing to pay for a rel. small performance gain.

[franc]

We should remember that if a country really want to order new fighters, the maneuverability will be the first consideration out of them, so more powerful engine always being better.

[Schorsch]

Originally Posted by franc

We should remember that if a country really want to order new fighters, the maneuverability will be the first consideration out of them, so more powerful engine always being better.

Wrong! Manouverability will hardly get under the Top 10 of reasons to chose an aircraft. When we reduce it to the performance issues, it possibly gets under the Top 5. Only if it is a showstopper it might be considered more.