F-35 Joint Strike Fighter

[asianobserve]

Even if the Pentagon can exercise the full capabilities of the new jet in simulations, there are questions as to how effective the F-35 will be against the latest Chinese and especially Russian integrated air defense systems in the real world. The Russians, especially, have been investing in long-wave networked radars operating in the UHF and VHF-bands for over two decades in their efforts to counter American stealth technology—particularly the Northrop Grumman B-2 Spirit strategic bomber. “The question is not who’s fighter is stealthier, the question is how stealthy are our aircraft relative to their long-wave UHF/VHF radars, designed more to return a holistic signature image of low observable aircraft,” Mike Kofman, a research scientist specializing in Russian military affairs at the Center for Naval Analyses told The National Interest. “Maybe JSF can make it going in, but it is a rather expensive platform, and could get into big trouble trying to make it out."

But the F-35 has one other serious liability, Kofman said—adding that U.S. Navy pilots are skeptical about single-engine designs. The F-35’s single Pratt & Whitey F135 engine—while immensely powerful, producing about 43,000lbs of thrust—also runs extremely hot. Unlike the Lockheed Martin F-22 Raptor, where the exhaust its F119 engines are flattened to reduce their infrared signature, the F-35 does not have any substantive measures to reduce the visibility of its exhaust from the enemy. The Russians—who build excellent infrared sensors—could use the F-35’s thermal signature to develop a weapons quality track to engage the stealthy new jet. “It’s probably has the hottest engine on the face of the planet,” Kofman said.

https://nationalinterest.org/blog/b...much-they-gave-it-nickname-velociraptor-35602

Why do you quote national interest. It's a pseudo news site! Running out of anti F-35 articles to quote?

 

[StealthFlanker]

Even if the Pentagon can exercise the full capabilities of the new jet in simulations, there are questions as to how effective the F-35 will be against the latest Chinese and especially Russian integrated air defense systems in the real world. The Russians, especially, have been investing in long-wave networked radars operating in the UHF and VHF-bands for over two decades in their efforts to counter American stealth technology—particularly the Northrop Grumman B-2 Spirit strategic bomber. “The question is not who’s fighter is stealthier, the question is how stealthy are our aircraft relative to their long-wave UHF/VHF radars, designed more to return a holistic signature image of low observable aircraft,” Mike Kofman, a research scientist specializing in Russian military affairs at the Center for Naval Analyses told The National Interest. “Maybe JSF can make it going in, but it is a rather expensive platform, and could get into big trouble trying to make it out."

Everyone like to talk about how such a "stealth killer" these VHF/UHF radar are, not many know their actual efficiency, spoiler: Nowhere nearly as much as you expected them to be.
I present you the presentation by Zoltán Dani (the one who shotdown F-117 in Serbia) - English subtitles available
Important part:
1)They used P-18 radar to detect F-117, but it still requires the lowest frequency setting L1 at 140 Mhz to detect F-117 (8:31)
2) Zoltán got intel from Janko Aleksic to know when to turn on his radar, as he had no target on his radar screen (18:31-19:10)
3) Following the order from headquarter, Zoltán and his team turn on their radar, switch through the frequency setting, start at L2 then L1 , L3 , L4. Only at L1, targets showed up, and they are all at distance 30 km or closer.

According to manufacturer specification, P-18 can detect a target with RCS =2.5m2 from 110 km if target cruises at 3 km altitude and 250 km if target cruises at 10 km altitude ( From the presentation, F-117 was cruising at 6 km altitude)
Extrapolate from the table
With radar height of 6.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 132.5 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.025m2 at frequencies >140 Mhz.
With radar height of 10.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 180 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.0025m2 at frequencies >140 Mhz.
Now you know how "effective" low frequency radar are against stealth.

But the F-35 has one other serious liability, Kofman said—adding that U.S. Navy pilots are skeptical about single-engine designs. The F-35’s single Pratt & Whitey F135 engine—while immensely powerful, producing about 43,000lbs of thrust—also runs extremely hot. Unlike the Lockheed Martin F-22 Raptor, where the exhaust its F119 engines are flattened to reduce their infrared signature, the F-35 does not have any substantive measures to reduce the visibility of its exhaust from the enemy. The Russians—who build excellent infrared sensors—could use the F-35’s thermal signature to develop a weapons quality track to engage the stealthy new jet. “It’s probably has the hottest engine on the face of the planet,” Kofman said.

Such nonsense
The fact that F-135 is a high bypass ratio engine already mean the exhaust fume will have lower radiance

Example of higher thrust high bypass engine still have lower plumes signature than lower thrust low bypass jet engine:

The serrated nozzle also cut down plumes length (which mean lower IR signature) since it makes the flow unstable:

And let not forget that the nozzle feathers have hollow slot so that ambient air can cool down the nozzle surface.

And of course, the nozzle is also masked by the stabs from many directions

 

[StealthFlanker]

If the photo above is too hard to imagine then see this

 

[BON PLAN]

If the photo above is too hard to imagine then see this

LOL.
You forget the M88 is made so as a cool fresh air surround the exhaust plume.

 

[BON PLAN]

Everyone like to talk about how such a "stealth killer" these VHF/UHF radar are, not many know their actual efficiency, spoiler: Nowhere nearly as much as you expected them to be.
I present you the presentation by Zoltán Dani (the one who shotdown F-117 in Serbia) - English subtitles available
Important part:
1)They used P-18 radar to detect F-117, but it still requires the lowest frequency setting L1 at 140 Mhz to detect F-117 (8:31)
2) Zoltán got intel from Janko Aleksic to know when to turn on his radar, as he had no target on his radar screen (18:31-19:10)
3) Following the order from headquarter, Zoltán and his team turn on their radar, switch through the frequency setting, start at L2 then L1 , L3 , L4. Only at L1, targets showed up, and they are all at distance 30 km or closer.

According to manufacturer specification, P-18 can detect a target with RCS =2.5m2 from 110 km if target cruises at 3 km altitude and 250 km if target cruises at 10 km altitude ( From the presentation, F-117 was cruising at 6 km altitude)
Extrapolate from the table
With radar height of 6.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 132.5 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.025m2 at frequencies >140 Mhz.
With radar height of 10.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 180 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.0025m2 at frequencies >140 Mhz.
Now you know how "effective" low frequency radar are against stealth.


Such nonsense
The fact that F-135 is a high bypass ratio engine already mean the exhaust fume will have lower radiance

Example of higher thrust high bypass engine still have lower plumes signature than lower thrust low bypass jet engine:

The serrated nozzle also cut down plumes length (which mean lower IR signature) since it makes the flow unstable:

And let not forget that the nozzle feathers have hollow slot so that ambient air can cool down the nozzle surface.

And of course, the nozzle is also masked by the stabs from many directions

Despite all you can explain, USAF itself is preoccupated by the F35 huge IR signature.
And about stealth, it's not the first time US thought they are away of the others....
Loss of the inboard canon... but US missiles were not so effective.
U2 shooted down by SA2 SAM...
F117 shooted down by SAM (with a non dedicated radar, old radar).

Strangely, more than 10 years after first flight, the stealth goose only train against US fighters.... are they afraid of the real result ?

 

[asianobserve]

Everyone like to talk about how such a "stealth killer" these VHF/UHF radar are, not many know their actual efficiency, spoiler: Nowhere nearly as much as you expected them to be.
I present you the presentation by Zoltán Dani (the one who shotdown F-117 in Serbia) - English subtitles available
Important part:
1)They used P-18 radar to detect F-117, but it still requires the lowest frequency setting L1 at 140 Mhz to detect F-117 (8:31)
2) Zoltán got intel from Janko Aleksic to know when to turn on his radar, as he had no target on his radar screen (18:31-19:10)
3) Following the order from headquarter, Zoltán and his team turn on their radar, switch through the frequency setting, start at L2 then L1 , L3 , L4. Only at L1, targets showed up, and they are all at distance 30 km or closer.

According to manufacturer specification, P-18 can detect a target with RCS =2.5m2 from 110 km if target cruises at 3 km altitude and 250 km if target cruises at 10 km altitude ( From the presentation, F-117 was cruising at 6 km altitude)
Extrapolate from the table
With radar height of 6.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 132.5 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.025m2 at frequencies >140 Mhz.
With radar height of 10.35 meters, P-18 will detect targets with RCS= 2.5 m2, cruising at 6km altitude from 180 km, reduce RCS by 10 times and we get 44% detection range reduction => F-117 RCS is smaller than 0.0025m2 at frequencies >140 Mhz.
Now you know how "effective" low frequency radar are against stealth.


Such nonsense
The fact that F-135 is a high bypass ratio engine already mean the exhaust fume will have lower radiance

Example of higher thrust high bypass engine still have lower plumes signature than lower thrust low bypass jet engine:

The serrated nozzle also cut down plumes length (which mean lower IR signature) since it makes the flow unstable:

And let not forget that the nozzle feathers have hollow slot so that ambient air can cool down the nozzle surface.

And of course, the nozzle is also masked by the stabs from many directions

Actually its kind of pointless to argue with our French friend on this matter. Just common sense, why do all major or first class air forces still want to buy or develop theor own stealth or LO fighters despite the much touted Chinese, Russian or even European advances in anti-stealth radars and passive detection systems? Heck, even our friend's own government and biggest aerospace company Dassault want to develop their own next gen stealth fighter? If stealth will not work in the future then why spend a lot of money designing new LO optimized airframes and stealth coatings? Why not, in the case of France, spend the money improving the sensors and weapons if Rafale in the next 50 years?

But for me common sense dictates that I should believe more the collective findings (for stealth) by major air forces than an internet fan boy.

 

[StealthFlanker]

LOL.
You forget the M88 is made so as a cool fresh air surround the exhaust plume.

And F-135 nozzle not only surrounded with cool ambient air, it also masked by the stabs and has the ability to shorten exhaust plumes.

Despite all you can explain, USAF itself is preoccupated by the F35 huge IR signature

No they don't
http://www.f-16.net/f-16_versions_article20.html

And about stealth, it's not the first time US thought they are away of the others....
Loss of the inboard canon... but US missiles were not so effective.

yet they still have 2 to 1 K/D ratio

U2 shooted down by SA2 SAM.

and? do you somehow think a weapon is only effective if it is 100% invincible?

F117 shooted down by SAM (with a non dedicated radar, old radar)

Non dedicated? what other aircraft could have get within 24 km from the P-18 without being detected? except stealth one like F-22/F-35 or B-2?
F-117 didn't even have RWR or Jammer, it always does the most dangerous sorties, yet, only shotdown once.

 

[BON PLAN]

And F-135 nozzle not only surrounded with cool ambient air, it also masked by the stabs and has the ability to shorten exhaust plumes.

Sure.
The frame of F35 is short versus F135 lengh, so even with all that goodies, the exhaust plume remains huge.
A 18Ton engine that can't make its plane supercruising.... means that the engine is used at a high rate.... means that the IR trace is huge.

Is as simple as that.
.

 

[BON PLAN]

yet they still have 2 to 1 K/D ratio

it was just an exemple, among others, to explain that all the US fighters ways are not good.
Stealth may be another.

 

[BON PLAN]

If stealth will not work in the future then why spend a lot of money designing new LO optimized airframes and stealth coatings?

Explain me why US Navy used and already produce old gen destroyers ? (Arleight Burke are not a stealthy design).
Explain me why US Navy is reluctant to F35 and prefer SH18 ?

 

[StealthFlanker]

Sure.
The frame of F35 is short versus F135 lengh, so even with all that goodies, the exhaust plume remains huge.

Except that it isn't, f-35 length is 15.37 m, Rafale length is 15.27m, so F-35 is longer, the fact that its body is thicker also means it is more likely to block the view to the exhaust plumes.
F-135 will have shorter plumes length than M88 since it has higher bypass ratio and serrated edges will make the flow more unstable and disperse quicker
Not to mention the whole nozzle of F-35 is also masked by vertical and horizontal stabs from most direction.

A 18Ton engine that can't make its plane supercruising.... means that the engine is used at a high rate.... means that the IR trace is huge.

Is as simple as that.

Except that it is absolutely not as simple as that. Engine thrust is a dynamic value which change significantly with speed and altitude. A high thrust engine which cannot make an airplane supercruise simply mean that it's high speed dynamic thrust is low, high speed dynamic thrust is decided by the inlet design (pressure recovery) and engine design such as bypass ratio.
To provide the same amount of thrust, an engine can either move a big amount of air slow, or small amount of air very fast. So just because an engine generates more thrust doesn't mean it is hotter. For example Mi-26 can generate far more thrust than mig-21 yet it still have lower IR signature

it was just an exemple, among others, to explain that all the US fighters ways are not good.
Stealth may be another.

Stealth isn't US way now, actually everyone is chasing it. From Russian, China, Japan, even France.

 

[asianobserve]

Explain me why US Navy used and already produce old gen destroyers ? (Arleight Burke are not a stealthy design).
Explain me why US Navy is reluctant to F35 and prefer SH18 ?

Ships are not penetrating assets. They are too big to be effectively hidden. On a cost benefit analysis it does not make much sense to make ships as stealthy as aircrafts.

The Navy is not reluctant to induct F-35s. It is buying 340 carrier versions, both for the USN and USMC (more than Rafale numbers, both in service and on order) while the USN is buying for the USMC another 340 F-35Bs. The combined F-35 planned purchase of the USN therefore stands at 680! Is that reluctance to you?

The only reason the USN keeps buying SH is due to retirement of older F-18Cs that needs replacement fast to sustain USN ops while waiting for the F-35. The USN has always opted for multi-platform in its carrier ops. So the F-35 will be paired with SH in service.

 

[asianobserve]

DoD, Lockheed Speed Up Negotiations on Lot 12 F-35 Contract

Ellen Lord, undersecretary for acquisition and sustainment at the Defense Department, has said DoD and Lockheed Martinhave accelerated efforts to finalize the 12th contract to procure at least 250 F-35 fighter aircraft, Bloomberg reported Tuesday.

https://blog.executivebiz.com/2018/...peed-up-negotiations-on-lot-12-f-35-contract/

 

[BON PLAN]

Except that it isn't, f-35 length is 15.37 m, Rafale length is 15.27m, so F-35 is longer, the fact that its body is thicker also means it is more likely to block the view to the exhaust plumes.
F-135 will have shorter plumes length than M88 since it has higher bypass ratio and serrated edges will make the flow more unstable and disperse quicker
Not to mention the whole nozzle of F-35 is also masked by vertical and horizontal stabs from most direction.

Another big LOL
Rafale shorter of 10cm but engine shorter of nearly 2m !!! (M88 : 3538cm, F135 : 5590cm).

And the length of Rafale is from the nose cone to the end : engine, when F35 length of F35 is from the nose cone to... the fin ! The frame of F35 is in the 14.5m.

For the thicker body, I agree. Is is so thick that with full dry thrust it can't supercruise (12.5 tons !)

No, the nozzle is not fully masked. Specially from the bottom.


What a discreet plume, indeed.

https://encrypted-tbn0.gstatic.com/...euxGj9zbCypnrG1d1Ex_MUPQ-mgKvO_YEPphsvErZHOAg

 

[BON PLAN]

Except that it is absolutely not as simple as that. Engine thrust is a dynamic value which change significantly with speed and altitude. A high thrust engine which cannot make an airplane supercruise simply mean that it's high speed dynamic thrust is low, high speed dynamic thrust is decided by the inlet design (pressure recovery) and engine design such as bypass ratio.
To provide the same amount of thrust, an engine can either move a big amount of air slow, or small amount of air very fast. So just because an engine generates more thrust doesn't mean it is hotter. For example Mi-26 can generate far more thrust than mig-21 yet it still have lower IR signature

The stealthy goose can or can't supercruise ?
the answer is : NO.

 

[BON PLAN]

Stealth isn't US way now, actually everyone is chasing it. From Russian, China, Japan, even France.

And US Navy don't look to the future ?

 

[BON PLAN]

Ships are not penetrating assets. They are too big to be effectively hidden. On a cost benefit analysis it does not make much sense to make ships as stealthy as aircrafts.

Yes, you are right.
See that picture :

 

[asianobserve]

Yes, you are right.
See that picture : View attachment 29609

Ever wonder why even the USN is not building anymore of those ships? The cost of stealth does not justify the benefits in ships.

It's different when it comes to frontline aircraft, especially fighters.

 

[Immanuel]

To listen & believe Froggie's remarks about stealth and IR profile is

 

[asianobserve]

Britain to buy 17 more F-35 fighter jets

The deal will mean Britain owns 35 of the stealth fighter jets by the end of 2022.

https://uk.reuters.com/article/uk-b...o-buy-17-more-f-35-fighter-jets-idUKKCN1NK1AV