keesje wrote:

Somewhere up the thread I suggested an interim solution might be viable as part of FCAS. F35 or Rafale which is are more optimized for ground attack / IDS than the "interceptor with bombs" Typhoon. It already has fully integrated 2 man cockpit, conformal tanks, combat proven Storm Shadow capability and mature AESA functionalities. Better than rebuilding the Typhoon.

I agree, but its unlikely.

Ozair wrote:

And here we go, a sign the engine fun and games has already begun...

MTU reveals next-generation fighter engine

MTU Aero Engines has revealed a new future powerplant for combat aircraft to be ready for fielding in the early 2030s.

The manufacturer disclosed the Next European Fighter Engine (NEFE) in a product brochure distributed at the ILA Airshow in Berlin in late April.

As noted in the brochure, the NEFE is being developed alongside the New Fighter (NF) combat aircraft and the Next-Generation Weapon System (NGWS) as part of a wider drive to preserve European defence industrial sovereignty under the Future Combat Air System (FCAS) project.

To meet the planned 2040 in-service date of the future combat aircraft being developed by Airbus and Dassault, MTU is already engaged in defining the aircraft’s twin-engined powerplant under the direction of the German Federal Ministry of Defence (BMVg).

In developing the NEFE, MTU has to meet a number of exacting requirements that include improved thrust and lower fuel consumption over current powerplants; low development and manufacturing costs; efficient maintenance and long projectable maintenance intervals; high electrical power extraction for aircraft systems; as well as maximum robustness and reliability.

“For the next-generation engine, MTU has identified various technologies of the future, which it wants to develop further,” the brochure stated, adding that these include multi-disciplinary methods and simulations in the design of engine concepts and in the components. Additive manufacturing and the use of ‘bionic design’ also open up new possibilities, MTU said. Furthermore, new designs and new materials, such as ceramic matrix composites, reduce the weight while enabling higher engine temperatures for more power delivery.

http://www.janes.com/article/79573/ila- ... ter-engine

I'm thinking a MTU / Snecma JV.

I heard India might be shopping for a new fighter too.

Slug71 wrote:

keesje wrote:

Somewhere up the thread I suggested an interim solution might be viable as part of FCAS. F35 or Rafale which is are more optimized for ground attack / IDS than the "interceptor with bombs" Typhoon. It already has fully integrated 2 man cockpit, conformal tanks, combat proven Storm Shadow capability and mature AESA functionalities. Better than rebuilding the Typhoon.

I agree, but its unlikely.

Ozair wrote:

And here we go, a sign the engine fun and games has already begun...

MTU reveals next-generation fighter engine

MTU Aero Engines has revealed a new future powerplant for combat aircraft to be ready for fielding in the early 2030s.

The manufacturer disclosed the Next European Fighter Engine (NEFE) in a product brochure distributed at the ILA Airshow in Berlin in late April.

As noted in the brochure, the NEFE is being developed alongside the New Fighter (NF) combat aircraft and the Next-Generation Weapon System (NGWS) as part of a wider drive to preserve European defence industrial sovereignty under the Future Combat Air System (FCAS) project.

To meet the planned 2040 in-service date of the future combat aircraft being developed by Airbus and Dassault, MTU is already engaged in defining the aircraft’s twin-engined powerplant under the direction of the German Federal Ministry of Defence (BMVg).

In developing the NEFE, MTU has to meet a number of exacting requirements that include improved thrust and lower fuel consumption over current powerplants; low development and manufacturing costs; efficient maintenance and long projectable maintenance intervals; high electrical power extraction for aircraft systems; as well as maximum robustness and reliability.

“For the next-generation engine, MTU has identified various technologies of the future, which it wants to develop further,” the brochure stated, adding that these include multi-disciplinary methods and simulations in the design of engine concepts and in the components. Additive manufacturing and the use of ‘bionic design’ also open up new possibilities, MTU said. Furthermore, new designs and new materials, such as ceramic matrix composites, reduce the weight while enabling higher engine temperatures for more power delivery.

http://www.janes.com/article/79573/ila- ... ter-engine

I'm thinking a MTU / Snecma JV.

I heard India might be shopping for a new fighter too.

Having said that, I suppose Snecma could give MTU a work share if Germany did order interim Rafales, and build that relationship for the FCAS power unit.
The F4 sounds like it could have some big upgrades. Including the PU.

https://www.defensenews.com/air/2017/03 ... -upgrades/

But still unlikely.

A Rafale with the EJ2000 would be sweet, but unlikely.

Slug71 wrote:

Slug71 wrote:

keesje wrote:

Somewhere up the thread I suggested an interim solution might be viable as part of FCAS. F35 or Rafale which is are more optimized for ground attack / IDS than the "interceptor with bombs" Typhoon. It already has fully integrated 2 man cockpit, conformal tanks, combat proven Storm Shadow capability and mature AESA functionalities. Better than rebuilding the Typhoon.

I agree, but its unlikely.

Ozair wrote:

And here we go, a sign the engine fun and games has already begun...

MTU reveals next-generation fighter engine


http://www.janes.com/article/79573/ila- ... ter-engine

I'm thinking a MTU / Snecma JV.

I heard India might be shopping for a new fighter too.

Having said that, I suppose Snecma could give MTU a work share if Germany did order interim Rafales, and build that relationship for the FCAS power unit.
The F4 sounds like it could have some big upgrades. Including the PU.

https://www.defensenews.com/air/2017/03 ... -upgrades/

But still unlikely.

I think we can't see this isolated. It part of e this in the bigger picture of French German defense cooperation. And it's even bigger, Germany pushes France to implement economic and labour reforms as part of longer term EC health, taking care of Trump, Iran, refugees etc, etc.

There are many more chapters in the bilateral Defense cooperation, Eurodrone, Space Surveillance, Transports, MPA, Airbus, Quick Reaction Forces, to name a few. Lot's to give & take. IMO a customized Rafale interim IDS solution could be part of it. The French would compensate /order elsewhere.

I note (flight) that unsurprisingly the US are suggesting the F-35.If you want a cost effective stealthy strike bomber it ain't a bad one.

Ozair wrote:

Additionally if Germany/France don’t factor in directed energy weapons it would be a failure as these will be a significant weapon system for all military platforms, land sea and air, by 2040.

They are...

Ozair wrote:

In developing the NEFE, MTU has to meet a number of exacting requirements that include improved thrust and lower fuel consumption over current powerplants; low development and manufacturing costs; efficient maintenance and long projectable maintenance intervals; high electrical power extraction for aircraft systems; as well as maximum robustness and reliability.

Some more reporting from the Berlin Air Show about the Germany Tornado replacement.

Lockheed tries to steer clear of German F-35 politics

Lockheed Martin executives Thursday dismissed critics’ claims that a German move to buy the F-35 fighter jet now would jeopardize future German-French combat aircraft cooperation.

Jack Crisler, vice president of business development, argued the U.S. defense giant’s product would be “complementary” to plans for future aircraft to be developed initially by Berlin and Paris.

“I don’t see it as competition,” he said.

Speaking to reporters at the Berlin Air Show, Crisler said operating the fifth-generation jet would give the German Air Force a taste of the types of technology to come, which could be helpful in making the generational jump later.

Company officials sought to frame the contractor’s response to a German request for information as a sheer business matter, independent of any political sensitivities surrounding the U.S. defense giant’s move toward the German market.

However, the playing field is anything but apolitical. Outgoing Air Force chief Lt. Gen. Karl Müllner reportedly was considered too outspoken by Defence Ministry leaders in his openness for the F-35, previously noting the stealth and standoff combat capabilities as desirable features for the service.

But Berlin officially favors an upgraded version of the fourth-generation Eurofighter ― built by a consortium of Airbus, Leonardo and BAE Systems ― as a replacement for the 90-strong Tornado jet fleet. The main argument is to keep European companies involved in building combat aircraft and, perhaps even more importantly, staying clear of disturbing Franco-German momentum in armaments cooperation.

Airbus Defence and Space chief Dirk Hoke told the Welt am Sonntag newspaper over the weekend that if Germany picks the American F-35, it would upend plans for the European co-development of a new-generation aircraft that would begin service sometime in the 2040s.

Crisler said Lockheed is working toward a per-unit cost of $80 million by 2020, at which point the global fleet will be roughly 50-50 in U.S. and international users. Company officials now aim to lower F-35 sustainment costs.

“We realize that the cost of ownership is a significant part of the aircraft,” Crisler noted.

U.S. Air Force Capt. Andrew Olson, who flew one of two F-35A aircraft from the United States to Germany, praised the advanced capabilities of the jet. The sensor package automates many tasks that were previously manual, such as those related to targeting, he said.

But he added that fourth-generation planes still have their place in combat scenarios for their ability to “put a lot of iron on target,” as their load capacities aren’t constrained by the limitations of stealth designs.

The F-35′s role, he said, is to sneak into enemy airspace undetected, “kick down the door” and allow other aircraft to stream in safely.

Besides the Eurofigher and the F-35, the Boeing-made F-15 and F/A-18 also are possible picks for what Berlin considers a bridging solution until a sixth-generation weapon is developed.

https://www.defensenews.com/industry/20 ... -politics/

mxaxai wrote:

They are...

Ozair wrote:

In developing the NEFE, MTU has to meet a number of exacting requirements that include improved thrust and lower fuel consumption over current powerplants; low development and manufacturing costs; efficient maintenance and long projectable maintenance intervals; high electrical power extraction for aircraft systems; as well as maximum robustness and reliability.

Perhaps but designing for DEW is more than just additional power... Spruiking more power extraction is essential anyway to operate a more electric jet which any new aircraft would have to adopt. The radar and EW systems, as well as operating significantly more computing power with various all aspect sensors, would require more than the current M88 and EJ likely offer.

Other news from the ILA Berlin air show, some points are just confirmation of earlier statements though:

https://www.wiwo.de/politik/deutschland ... 20498.html
http://www.tagesschau.de/wirtschaft/air ... s-101.html
http://www.spiegel.de/wissenschaft/tech ... 04755.html

• German MoD von der Leyen stated her preference of the Eurofighter as immediate Tornado replacement
• LM presented the F-35 in detail to the german MoD, including delivery times, stealth characteristics and prices
• FCAS shall have one version only, not separate specifications for each customer (unlike A400M or Eurofighter)
• France (Dassault) shall take take the lead regarding airframe development
• Germany (Airbus & others) shall provide peripheral systems like supporting UAV's (which are controlled by FCAS pilots), weapons, satellites, radars,... Airbus already has the lead for the MALE drone that is supposed to be ready for purchase by year's end
• Desire to be able to fly FCAS without a pilot
• FCAS shall be less of a weapon by itself and more of a weapon control station, pilot's main job is not to fly but to process information and guide weapons to their targets

Full scale mock-up of the drone, MTOW 11 tons:


Some things remain unclear, for example:

• Will Germany allow the export to wherever France wants to?
• Will it be able to carry nuclear weapons? Will it be able to operate from carriers?
• Is Germany willing to use armed UAV's or will they stick to reconnaissance only?

On the ILA press conference, von der Leyen stressed again Germany's preference for the Eurofighter to replace the Tornado. As mentioned before Germany and France also signed an agreement to develop the FCAS together. Both MoDs showed unity by arriving in an A400M flanked by Eurofighters and Rafales.

Some interesting rumors about the F-35 circulated on the ILA. LM had announced they would fly the plane but this didn't happen apparently because German company Hensoldt introduced their new passive radar system on the ILA (see https://www.armyrecognition.com/april_2018_global_defense_security_army_news_industry/hensoldts_twinvis_passive_radar_in_live_operation.html) which uses reflections of TV and radio signals for detection.
LM representatives were afraid that it would easily detect the F-35; thereby making their main marketing argument moot.

vr773 wrote:

On the ILA press conference, von der Leyen stressed again Germany's preference for the Eurofighter to replace the Tornado. As mentioned before Germany and France also signed an agreement to develop the FCAS together. Both MoDs showed unity by arriving in an A400M flanked by Eurofighters and Rafales.

Some interesting rumors about the F-35 circulated on the ILA. LM had announced they would fly the plane but this didn't happen apparently because German company Hensoldt introduced their new passive radar system on the ILA (see https://www.armyrecognition.com/april_2018_global_defense_security_army_news_industry/hensoldts_twinvis_passive_radar_in_live_operation.html) which uses reflections of TV and radio signals for detection.
LM representatives were afraid that it would easily detect the F-35; thereby making their main marketing argument moot.

Not sure where the suggestion that the F-35 was going to be flying came from. The US Heritage Flight, which conducts the displays and flights at airshows, only released their schedule on the 18th Jan 2018 and had always indicated Berlin ILA was static.

2018 Appearance Schedule – US Air Force F-35 Lightning II Heritage Flight Team

March 17-18: Luke Air Force Base, AZ
March 23-24: NAS Kingsville, TX

April 3-8: FIDAE – Santiago, Chile (Static only)
April 25-29: ILA Berlin – Berlin, Germany (Static only)

May 25-27: Miami, FL

June 9-10: North Kingston, RI
June 15-17: Ocean City, MD

July 13-15: Royal International Air Tattoo (RIAT) – RAF Fairford, United Kingdom (HF profile fly by/static)

August 10-12: Offutt Air Force Base, NE
August 17-19: Chicago, IL
August 31-September 2: CIAS – Toronto, Ontario

September 21-23: California Capitol Airshow – Sacramento, CA

October 1-6: USAF Academy Football Game / CORONA

http://airshowstuff.com/v4/2018/usaf-f- ... -released/

vr773 wrote:

Some interesting rumors about the F-35 circulated on the ILA. LM had announced they would fly the plane but this didn't happen apparently because German company Hensoldt introduced their new passive radar system on the ILA (see https://www.armyrecognition.com/april_2018_global_defense_security_army_news_industry/hensoldts_twinvis_passive_radar_in_live_operation.html) which uses reflections of TV and radio signals for detection.
LM representatives were afraid that it would easily detect the F-35; thereby making their main marketing argument moot.

I remember in the aircraft recognition courses (I served in an AA unit as radar operator), that a lot of training video sequences showing foreign aircraft were recorded at air shows using the TV following system of our radar unit. If I am not mistaken also F-117 footage was there, showing the aircraft in the middle of the cross hair.

Anyway the F-35s did not arrive by train, so some interesting testing was possible when the aircraft flew in.

Should LM (or better the operators) also not be interested in knowing potential weaknesses of the F-35 or potential future counter possibilities? Similar like the US Navy was very interested in the Swedish stealth submarine, that in exercise sunk a carrier undetected?

This marketing anyway. The F-35 will carry signature enhancers anyway.

Below is an interesting interview with the departing Chief of the German Air Force LtGen Mullner conducted at ILA Berlin. Mullner makes it pretty clear that while the current Eurofighter has received A2G capabilities it will struggle against modern Russian Air Defence Systems and will be reliant on being deployed with or after "state of the art aircraft" and employed.

It is undisputed that the EUROFIGHTER as fighter aircraft is the backbone of our air defence. With the successfully completed test campaign in Sweden and the permission granted to use the GBU-48, we have indeed passed an important milestone on the road towards multirole capability, i.e. the EUROFIGHTER as fighter bomber.The EUROFIGHTER can also be used in the air-to-ground role and has been reported to the NATO Response Force as multirole fighter aircraft and fighter bomber from the beginning of this year. However, this new role of the EUROFIGHTER aircraft also has limits, especially when we think of scenarios with powerful air defence.

Russia has state-of-the-art air defenve missile systems and is stationing and exporting them. It is not without reason that many of our European partners and our allies from across the Atlantic have introduced combat aircraft that make it possible for pilots to enter an airspace that is protected by advanced air defence systems.The EUROFIGHTER lacks the required low detectability depending on the design of the radio and data transfer systems and, more significantly, on the outer form of the aircraft which cannot be changed.

For us, this means that the EUROFIGHTER as a fighter bomber can only fulfil its tasks convincingly when employed together with or after a successful employment of state-of-the art aircraft that have a sufficiently reduced signature in the entire electromagnetic spectrum. Furthermore, it still needs considerable additional support through an effective use of electronic warfare assets.

http://www.monch.com/mpg/images/exhibit ... 2-2018.pdf

More info is available in the article at the above link.

Wise ass comment alert; no duh.

Somebody plz explain how a 4 th gen bomber gets close enough to emitters to make a difference.

seahawk wrote:

This marketing anyway. The F-35 will carry signature enhancers anyway.

Not sure whether signature enhancers would change anything for broad RF mix, this system seems to capture...

rheinwaldner wrote:

seahawk wrote:

This marketing anyway. The F-35 will carry signature enhancers anyway.

Not sure whether signature enhancers would change anything for broad RF mix, this system seems to capture...

The fitted luneberg lens typically operate across a wide spectrum, the one at the following link operates from S band to Ku and while I have no idea if that is the one fitted to the F-35 is demonstrates broad frequency coverage. http://targetsystems.qinetiq.com/static ... s_2015.pdf

The specified passive detection system would operate at lower frequencies but I doubt the system would gain much. These types of passive systems has several significant disadvantages compared to a standard active radar and we know that F-35 shaping, and RAM, is effective down to the VHF range. Given the presence of the lens and potentially other features to increase RCS I don't see a basis for the rumours, especially in the context of the intention always being a static display.

Ozair wrote:

rheinwaldner wrote:

seahawk wrote:

This marketing anyway. The F-35 will carry signature enhancers anyway.

Not sure whether signature enhancers would change anything for broad RF mix, this system seems to capture...

The fitted luneberg lens typically operate across a wide spectrum, the one at the following link operates from S band to Ku and while I have no idea if that is the one fitted to the F-35 is demonstrates broad frequency coverage. http://targetsystems.qinetiq.com/static ... s_2015.pdf

The specified passive detection system would operate at lower frequencies but I doubt the system would gain much. These types of passive systems has several significant disadvantages compared to a standard active radar and we know that F-35 shaping, and RAM, is effective down to the VHF range. Given the presence of the lens and potentially other features to increase RCS I don't see a basis for the rumours, especially in the context of the intention always being a static display.

Luneberg lens (as well as corner reflectors) are only useful, when the radar emitter and receiver is located at the exactly same spot. The presented system (no idea whether it holds all promises, never heard of it before) in theory is therefore not impacted by such reflectors. Likewise it should not be impacted by stealth designs, that just prevent radar waves to be returned in the direction, where they came from. The stealth design would have to fully absorb an immensely wide spectrum of RF frequencies, in order to make a difference.

You make some claims without providing evidence (that passive systems have significant disadvantages and stealth effectiveness down to VHF range) so could you elaborate a bit, why you think this to be the case?

In the end it does not matter for Germany. With only 4 mission capable Eurofighters, there simply is no need to buy a new fighter. The only solution is to shrink the Luftwaffe down to 2 wings with 24 Eurofighters each that provide basic air space patrol over Germany and scrap everything else. The money can be used for better things outside of the armed forces.

rheinwaldner wrote:

Luneberg lens (as well as corner reflectors) are only useful, when the radar emitter and receiver is located at the exactly same spot.

Why? The EM radiation impacting on the F-35 is scattered when it encounters the Luneberg lens. The passive system in question looks across specific frequencies for reflected EM radiation. Why would it not identify a bright reflection from the F-35 given the whole point of the lens is to magnify and scatter the radiation.

rheinwaldner wrote:

The presented system (no idea whether it holds all promises, never heard of it before) in theory is therefore not impacted by such reflectors. Likewise it should not be impacted by stealth designs, that just prevent radar waves to be returned in the direction, where they came from. The stealth design would have to fully absorb an immensely wide spectrum of RF frequencies, in order to make a difference.

Not quite. While planform alignment and subsequent reflection is a major component of a stealth platform the aircraft is also covered, especially in the case of the F-35, of RAM that absorbs EM radiation across a range of frequencies. For example LM has a patent for CNT RAM as can be seen here, https://patents.google.com/patent/US20100271253A1/en which as the description states is active from 0.10 MHz to 60 GHz.

rheinwaldner wrote:

You make some claims without providing evidence (that passive systems have significant disadvantages and stealth effectiveness down to VHF range) so could you elaborate a bit, why you think this to be the case?

For starters passive systems that use waves reflected by TV and radio stations have significantly reduced accuracy by the nature of the reflected wave, certainly not enough to target weapons against. They aren't particularly high powered either. They are low frequency and have large wavelength, thereby creating regions of uncertainty. Second, the passive systems work best at low altitudes, the higher an aircraft is the less reflects are received at ground stations, again based on the nature of the reflected waves being ground based and polarized to move along the ground.

Finally, we have some good info on F-35 stealth characteristics from here, https://pdfs.semanticscholar.org/6bcd/d ... c1dbe0.pdf which also goes into detail on PCL systems, page 21 of the PDF.

seahawk wrote:

In the end it does not matter for Germany. With only 4 mission capable Eurofighters, there simply is no need to buy a new fighter. The only solution is to shrink the Luftwaffe down to 2 wings with 24 Eurofighters each that provide basic air space patrol over Germany and scrap everything else. The money can be used for better things outside of the armed forces.

Capitulation after self-defeat? Without enemy influence? Betting on more motivated friends to save your butt?

rheinwaldner wrote:

seahawk wrote:

In the end it does not matter for Germany. With only 4 mission capable Eurofighters, there simply is no need to buy a new fighter. The only solution is to shrink the Luftwaffe down to 2 wings with 24 Eurofighters each that provide basic air space patrol over Germany and scrap everything else. The money can be used for better things outside of the armed forces.

Capitulation after self-defeat? Without enemy influence? Betting on more motivated friends to save your butt?

As nobody wants the butt of Germany, it is only efficient. If you have a asset that you can not found enough to be useful, it is wise to scrap the asset as founding a useless asset is wasting money.

Ozair wrote:

rheinwaldner wrote:

Luneberg lens (as well as corner reflectors) are only useful, when the radar emitter and receiver is located at the exactly same spot.

Why? The EM radiation impacting on the F-35 is scattered when it encounters the Luneberg lens. The passive system in question looks across specific frequencies for reflected EM radiation. Why would it not identify a bright reflection from the F-35 given the whole point of the lens is to magnify and scatter the radiation.

This is wrong. Radar reflectors do not scatter radar waves. They emit them back in the same direction from where they came from. No matter at what angle the wave hits the reflector, the signal is sent back at the same angle. I remember like it was yesterday in Physics lab how you can see yourself from any direction in two mirrors that touch each other with a 90° angle in between. The Luneburg lens is nothing else.

Thinking about that, I noticed that for passive detection systems the Luneburg lens actually even decreases the RCS! The moment the whole plane becomes a perfect radar reflector, the passive system would not detect anything anymore. Because all incoming radio signals would be sent back to their original transmitter.

Ozair wrote:

For starters passive systems that use waves reflected by TV and radio stations have significantly reduced accuracy by the nature of the reflected wave, certainly not enough to target weapons against. They aren't particularly high powered either. They are low frequency and have large wavelength, thereby creating regions of uncertainty. Second, the passive systems work best at low altitudes, the higher an aircraft is the less reflects are received at ground stations, again based on the nature of the reflected waves being ground based and polarized to move along the ground.

Finally, we have some good info on F-35 stealth characteristics from here, https://pdfs.semanticscholar.org/6bcd/d ... c1dbe0.pdf which also goes into detail on PCL systems, page 21 of the PDF.

Even as a starter I have noticed in the PDF on page 6 that for VHF the RCS is red in all directions.

rheinwaldner wrote:

This is wrong. Radar reflectors do not scatter radar waves. They emit them back in the same direction from where they came from. No matter at what angle the wave hits the reflector, the signal is sent back at the same angle. I remember like it was yesterday in Physics lab how you can see yourself from any direction in two mirrors that touch each other with a 90° angle in between. The Luneburg lens is nothing else.

We have no information on how the lens is specifically designed, if lens sit coincident to each other and are multiple within one location or what types of material are used in their construction, including which parts have metal and other radar reflecting material within the various layers. I am pretty confident that the designers of stealth aircraft are aware of wavelengths and how they refract, including radar waves from VHF and below systems, and will have taken these things into consideration when designing devices to enhance the RCS of the platform.

rheinwaldner wrote:

Even as a starter I have noticed in the PDF on page 6 that for VHF the RCS is red in all directions.

The RCS approximations for the F-35 in that paper were a worst case scenario, in that specific case taken from Air Power Australia assessments. If you know anything about APA they were never a friend of the F-35 and their assessment is wrong in multiple areas. Using an APA assessment gives credibility to the results given the worst case nature of the model. If you read the article it clearly shows how the F-35, even at lower frequencies, gains a significant benefit from its stealth characteristics. Add to that the LM patent for RAM that works down to below HF frequencies.

Ozair wrote:

We have no information on how the lens is specifically designed, if lens sit coincident to each other and are multiple within one location or what types of material are used in their construction, including which parts have metal and other radar reflecting material within the various layers.

We know the purpose, right? That's all we need to know.
A signature enhancer shall return radar waves to the emitter. The more it does that, the less waves are scattering so the less a passive system has to something work with.

Ozair wrote:

I am pretty confident that the designers of stealth aircraft are aware of wavelengths and how they refract, including radar waves from VHF and below systems, and will have taken these things into consideration when designing devices to enhance the RCS of the platform.

You are mixing wavelengths with directional reflection. The discussion about the Luneburg lenses has nothing to do with wavelengths. A good radar reflectors simply increases the RCS area by its cross section area (because it fully reflects all RF back to where they came from) over all wavelengths. The implication is, that emitter and receiver need to be located at the same spot. For all other scenarios (= passive systems) the opposite is the case.

A good radar reflector, for all wavelengths, that even covers the visible light, costs some cents and consists of 3 sheets of thin aluminium. We have built such throw away reflectors and did let them climb with a ballon many times in order to measure the current wind speed at different altitudes with our radar.

What reflects radar wave from one emitter reflects waves from any other emitter just as well. So the reflector will also reflect any radio or TV signal more strongly.

rheinwaldner wrote:

A signature enhancer shall return radar waves to the emitter. The more it does that, the less waves are scattering so the less a passive system has to something work with.

The echo enhancer only works on energy passing into its aperture. That is small (but sufficient, as its echo attenuation works on distance^2 and not distance^4 attenuation that the regular scan return shows.
But the full aperture of the aircraft creates useable scatter from radio waves for a passive system.
i.e. signature enhancers do nothing ( neither positive nor negative ) in this context.

seahawk wrote:

What reflects radar wave from one emitter reflects waves from any other emitter just as well. So the reflector will also reflect any radio or TV signal more strongly.

Absolutely correct. How many are reflected is just not the relevant question.

Guys do me a favour, and read the Wikipedia article about radar reflectors. Before you have clarity about the following questions, don't start thinking about the passive detector thingy:
- How many percentage of radar waves are reflected from a normal sheet of metal? (answer: 100%)
- In which direction? (answer: another where it came from, except when sending exactly along the sheet normal)
- How many percentage of radar waves is reflected from the reflector? (100%)
- In which direction? (always back to the sender)

And TwInvis works like a radar with more than one emitter. It still depends on the signal being reflected by the target. So either it will pick up the increase in reflected energy directly or indirectly by measuring a weaker signal wave reaching TwInvis from the emitter.

I hoped it would be clear by now. So let me explain the basics. It is really not rocket science on the level to which we go here:

How does normal radar work?
The radar signal is emitted from the radar and thrown back from the aircraft. Of all the received radar signals only a small part is reflected to the sender, most waves are scattered in all directions. For the radar to be reflected to the radar sender, several conditions must be met: only the aircraft surface, that is positioned perpendicularly to the incoming radar waves does reflect them back into the same direction, from where they came from. For short moments this can be a whole wing, but most of the times the strongest echos are received from curved edges. E.g. wing leading or trailing edges. Also Propellers (or fans) are very bad because all its edges are perpendicularly many times per second. Carefully note, that even here radar waves are mostly scattered around, which means nothing else, that they are reflected in a not useful directions (where the radar receiver is not located). Still all the edges create a sufficiently large radar cross section. If surfaces stand orthogonal vs each other, the geometry acts as radar reflector with a significantly increased radar cross section.



How does stealth work?
Mostly by using an aircraft geometry, where the frame is shaped and the edges are designed carefully in a way, that the RF reflections back to the sender are minimized. Nearly all incoming radar energy (that is not absorbed by RAM) is scattered (= reflected, but not in the direction, from where it came from).

How does a signature enhancer work?
By not scattering the radar in all directions, but by reflecting each incoming RF wave exactly back to its origin. More than anything else, it primarily controls the direction of the responding emission, not its strength. The cross section of the luneburg lens is basically added to the RCS of the plane. If the plane has an RCS of 0.00143m^2, a Luneburg lens of 0.3m diameter adds an RCS of 0.0706m^2 (the area of the circle).

How does the passive radar work?
As the sender is located somewhere else, it works in principle with scattered RF only. It is basically the anti pattern, of how normal radar works. Normally a radar receives what is thrown back in its direction. Exactly the opposite happens with passive radar: the portion, that is exactly thrown back is useless for it. It has to work with the rest (and, of course, not the whole energy is scattered in the direction where the passive radar sits). But, on the other hand, it works with a large number of emitters.

Classic aircraft vs classic radar, passive radar
So a classic aircraft scatters a lot of RF around and reflects sufficient amount of RF back to the radar station. The passive radar also receives a lot of input from many senders.

Stealth aircraft vs classic radar, passive radar
A stealth aircraft scatters still a lot of RF around but reflects nearly nothing back in the direction, where it came from. The passive radar still receives many signals.

Stealth aircraft with signature enhancer vs classic radar, passive radar
A stealth aircraft with signature enhancer scatters also a lot around, reflects nearly nothing from itself but a notable amount of RF from the enhancer back to the sender. So the passive radar does not receive a stronger signature at all (as many seem to expect due to the enhancer), but in theory even weaker signal (because some portion of the aircraft surface is covered by the Luneburg lenses, which don't scatter received RF but direct it back to the sender (which is per definition located somewhere else, than the passive radar receiver)).

WIederling wrote:

The echo enhancer only works on energy passing into its aperture. That is small (but sufficient, as its echo attenuation works on distance^2 and not distance^4 attenuation that the regular scan return shows.

Echo attenuation is more something I heard in relation to rain clouds in between radar and target. So what is the distance, you mentioned?

rheinwaldner wrote:

WIederling wrote:

The echo enhancer only works on energy passing into its aperture. That is small (but sufficient, as its echo attenuation works on distance^2 and not distance^4 attenuation that the regular scan return shows.

Echo attenuation is more something I heard in relation to rain clouds in between radar and target. So what is the distance, you mentioned?

classic radar antenna to detectable object.
the radar pulse suffers from distance^2 attenuation to the target ( same energy through a distance^2 growing apperture window)
at the target the puse creates a diffuse point source. the receiver sees the same distance^2 attenuation of this point source
for the diffuse reflecting target:
Energy received thus is pulse energy * distance^-2 * target aperture * distance^-2 .. ~= distance^-4 * target aperture.

for the retroreflector target:
the radar pulse suffers from distance^2 attenuation to the target, all energy in that aperture is reflected back to the emitter.
Energy received thus is pulse energy * distance^-2 * target aperture

Low observable.
A: create as few as possible surfaces that work as a mirror and arrange them thus that they do not reflect back to an expected radar source. ( surfaces : compare Have Blue to MBB Lampyridiae, less facets! ) break continuous outline panels ( avoid slit antenna effects.
This is less effective if you can illuminate and/or receive from various directions.
Additionally mirror surfaces need to be large in relation to wavelength used. What is stealthy for X-Band and above is probably much less effective for lower frequencies. )


B: make surfaces absorbent
( this works in very case. )

WIederling wrote:

...

This must be one of your longer posts! Its a bit cryptic but after reading it carefully it makes perfect sense, thanks. Is all correct what you write...

TwInvis uses 2 methods of detection.

It basically measures the natural signal scattering from various emitters. Targets are identified by an increase in signal strength as well as by a decrease because both measurements indicate that there is something disturbing the radio wave either by reflecting more or by dispersing more.

While this article is nothing new in the sense the french feel they should be in control and their government will pump in money to support that, it touches the experience on big pan European programs over the last decades.

I think the Germans have drawn the same conclusions. European integration is great but having changing politicians form 6-8 different countries fighting for their employment share is killing program speed & efficiency.

https://www.defensenews.com/global/europe/2018/04/20/is-european-cooperation-a-drag-on-arms-programs-france-audit-office-says-yes/

In case of the new euro stealth fighter bomber. I would set up

Office in Germany (they pay most), close to the French border
Appoint an experienced international BoD (best, not per definition German / French)
Outsource in a business like way. protected against greedy national lobby's & national appeal openings.
If you don't speak/write English well, you are not in, no translation circuses. Avoid lingual sub grouping.
Luftwaffe / French Air Force set realistic specifications & no evolving integrated FCAS dreaming.
No new partners/ customers the first 6 years
Compressed 2030 EIS driven planning

keesje wrote:

Office in Germany (they pay most), close to the French border
Appoint an experienced international BoD (best, not per definition German / French)
Outsource in a business like way. protected against greedy national lobby's & national appeal openings.
If you don't speak/write English well, you are not in, no translation circuses. Avoid lingual sub grouping.
Luftwaffe / French Air Force set realistic specifications & no evolving integrated FCAS dreaming.
No new partners/ customers the first 6 years
Compressed 2030 EIS driven planning

No nonEU parts. Big selling point at the moment.

Best regards
Thomas

The Drive reports that Germany is looking to retain nuclear sharing by adding the capability to carry B61s to the Eurofighter. I personally favor ending nuclear sharing altogether because it's useless and because I don't consider the US a reliable military partner anymore. But equipping the Eurofighter would at least avoid having to buy US aircraft once the Tornado is fully phased out.

http://www.thedrive.com/the-war-zone/21 ... lear-bombs

[quote="vr773"]The Drive reports that Germany is looking to retain nuclear sharing by adding the capability to carry B61s to the Eurofighter. I personally favor ending nuclear sharing altogether because it's useless and because I don't consider the US a reliable military partner anymore. But equipping the Eurofighter would at least avoid having to buy US aircraft once the Tornado is fully phased out.

http://www.thedrive.com/the-war-zone/21 ... lear-bombs[/

How many stories have been published about very poor readiness rates accross multiple branches of the German military?

I’ll bet the US is more prepared to defend Germany than the Germans are.

Planeflyer wrote:

How many stories have been published about very poor readiness rates accross multiple branches of the German military?

I’ll bet the US is more prepared to defend Germany than the Germans are.

I always forget that the Russians are about to attack until you remind me. Personally, I don't think the demagogues currently in charge in America are prepared to do anything of value - especially not honoring international treaties. I don't mean General Mattis here, who I highly respect, but it just takes a tweet for him to be gone too.

As for readiness of German troops and gear, much of the reporting is true and much of it isn't.
It sells to get people enraged and that's why Der Spiegel for example loves to blow readiness reports out of proportion. If you look closer you see that the Bundeswehr has done a lot in the last couple of years to turn things around (including increasing overall spending) but the unpopular truth is that it takes time to see results. A lot of Bundeswehr bases are currently being refurbished for example but this kind of information doesn't t make it into the newspapers.

vr773 wrote:

Planeflyer wrote:

How many stories have been published about very poor readiness rates accross multiple branches of the German military?

I’ll bet the US is more prepared to defend Germany than the Germans are.

I always forget that the Russians are about to attack until you remind me.
......
As for readiness of German troops and gear, much of the reporting is true and much of it isn't.

compromising readiness was de Meziers work. continued by v.d.Leyen unchanged.

I have wondered on occasion if "kaputtgespart" doesn't also avoid having to "help" the US in some military adventure or other.
( .. and there is zero probability of an _unprovoked_ Russian attack. )
Germany still adheres to the promises made at the time ( 2+2 ). No NATO forces in the "Neue Bundesländer".

vr773 wrote:

I always forget that the Russians are about to attack until you remind me.

Russia is not prepared to attack anyone, least Germany. They may be somewhat prepared to defend their country and annex defenseless regions, but they cannot run a successful conventional war against anything more powerful than the Baltic states. Almost every non-trivial offensive operation of the Soviet Union or post-Soviet Russia has been a failure, and I believe that they have learned something. Putin is not in that desperate position that he would need to do stupidities to stay in power (but cannot predict how his successor will be).

Front line countries just have to make clear that they are not trivial to be occupied.

(And neither any European country alone or together has any capacity to attack Russia, so that Putin has nothing to fear from the west.)

YIMBY wrote:

vr773 wrote:

I always forget that the Russians are about to attack until you remind me.

Russia is not prepared to attack anyone, least Germany. They may be somewhat prepared to defend their country and annex defenseless regions, but they cannot run a successful conventional war against anything more powerful than the Baltic states. Almost every non-trivial offensive operation of the Soviet Union or post-Soviet Russia has been a failure, and I believe that they have learned something. Putin is not in that desperate position that he would need to do stupidities to stay in power (but cannot predict how his successor will be).

Front line countries just have to make clear that they are not trivial to be occupied.

(And neither any European country alone or together has any capacity to attack Russia, so that Putin has nothing to fear from the west.)

Out of one side of your mouth Germany has no need of USA, out of the other USA is not a reliable defense partner. Which is it?

Planeflyer wrote:

Out of one side of your mouth Germany has no need of USA, out of the other USA is not a reliable defense partner. Which is it?

Where is your beef?

1: Germany has currently no need to put up a bulwark against Russian.
( only danger currently is Germany getting inducted into a conflict the US causes.

2: Germany sees the US as an extremely unreliable defense partner ( in scope of NATO.)
( one item being the US trying to piss off the RF at every occasion. unprovoked at that.)

This is two logically linked statements.

Good question the beef is this:

NATO has kept the peace for almost 80 years in a region thas seen large wars on average once a generation for almost a thousand years.

Many of these have erupted unexpectedly and especially from the East.

And almost all were generated by actions of country or countries A in response to be surrounded by countries B and C.

Think France and Germany in the 16-20 th centuries. British policy was to align w the 2nd or 3rd continental power against the first which guaranteed war as a routine.

NATO’s mission was to eliminate such uncertainty.

NATO has largely succeeded but it must Hurd against putting Russia in the position of country A. Russia is most worried about being surrounded by China and NATO.

So now we come to the issue of German defense. The argument against the F35 is that it is a non Europeon product that is not needed.

The argument put forward for a Europeon product is that

Sorry hit send too soon.

The argument for a Europeon ac tacitly relies on the US since Europe does not currently have a product that is mission capable.

So on the one hand there is no need to buy the F35 since it is not needed but on the other hand the same people who argue for this argue that because the US is now unreliable Europe needs to have its own capabilities.

If there is no threat why waste money on either solution( in reality there is only one solution).

In summary nobody knows when push is going to coming to shove so advanced prep is the prudent course.

And based on the track record if you don’t buy the F35 you will only rely on it anyway. The difference will be Germany airspacevwill be in the hands of non German NATO pilots flying F35’s and F22’s.

vr773 wrote:

As for readiness of German troops and gear, much of the reporting is true and much of it isn't. .

Yup, People often forget that in the German Army Peace time rules apply in piece times, and by that I mean civilian rules.
That is why for example armored vehicles in Afghanistan where often not mission capable, their emissions certificate was up and no one got around to renew it. Those where perfectly able to fight.

Best regards
Thomas

https://amp.dw.com/en/germanys-lack-of- ... a-42663215

I can just hear it now from W. German officials are so caught up w Trump’s tweets they can’t make time to fix the problem.

Actually the truth is the reason for Trump’s statements on the subject; why should we spend German money on the basics when we can always fall back on the unreliable Americans ?

Planeflyer wrote:

https://amp.dw.com/en/germanys-lack-of-military-readiness-dramatic-says-bundeswehr-commissioner/a-42663215

I can just hear it now from W. German officials are so caught up w Trump’s tweets they can’t make time to fix the problem.

Actually the truth is the reason for Trump’s statements on the subject; why should we spend German money on the basics when we can always fall back on the unreliable Americans ?

Just so I understand, is your point that Germany is purposely starving its military because of a German government strategy that is based on relying on the US military presence in Germany?
If so, that point is not supported by the facts on either side of the Atlantic. Germany has initiated reversing the reorientation that happened under zu Guttenberg. And are you implying Trump is reliable?

I don't know which of Trump's statements you're referring to but if it's the claim that Germany "owes" the US money, here is another fact for you: The US continued to maintain military bases in Germany after the cold war because it served their own geopolitical strategy and interests (e.g. the Landstuhl hospital for soldiers wounded in the American wars in Asia) and not because Germany wanted them to.

Sorry it was a bad attempt at sarcasm. my reference to W was to Wiederling and his many conspiracy theories.

German policy is clear and well supported by many and maybe even most Germans; let’s not spend our money as long as the USA will.

You say it is good for the US to stay in Europe.

Ok, let’s put good and bad aside for just a moment and ask ourselves what is the over under and how many years it will take for major Europeon war to breakout after the US leaves the continent?

If you could convince me this wouldn’t happen then it would be god for everyone that the US come home.

The problem is that my sons or for sure my grandsons would have to do what my father, uncles and grandfather did.

All of this not meant to disparage Europe or Europeans. The reality is that Europe is a target rich environment w no natural defenses and so many competing interests that w/o a US led NATO a common defense is not possible.

German recalcitrance on defense spending is a jus one small example of what I mean by competing interests that would lead to the next Europeon wide war.

I would say most Germans, say "do not spent much on the armed forces, as conventional conflict is unlikely". They would not spent one Euroe more if US troops would leave Europe.

Agree but this is not the right question.

Planeflyer wrote:

German policy is clear and well supported by many and maybe even most Germans; let’s not spend our money as long as the USA will.

This is more or less wrong.
With the up front example of the US spending to no end on allegedly defense outlay and creating and then aggravating a long line of global problems spending more on defense appears to be counter intuitive. ( Einstein: repeating the same action over and over and expecting a diifferent outcome is madness )

Planeflyer wrote:

German recalcitrance on defense spending is a jus one small example of what I mean by competing interests that would lead to the next Europeon wide war.

Just like in the US there is a growing group of people with "Großmannssucht" in Europe. They forgot what war is like.