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F-35's radar invisibility cloak in question

105 points by XnoiVeX 7y ago

blakesterz 7y ago
Interesting, apparently it's because of "passive radar" which I'd never heard about before... "Passive radar equipment computes an aerial picture by reading how civilian communications signals bounce off airborne objects." https://en.wikipedia.org/wiki/Passive_radar https://en.wikipedia.org/wiki/Passive_radar
- lallysingh 7y ago
  I've seen a presentation (over 10 yrs ago) where passive radar was set up as a secondary sensor system that is hard to locate because it's not transmitting. One attack scenario is with a stealth plane first attacking the radar systems, then regular planes come in after. So the passive systems would stay up, as most attacks won't target civilian infrastructure. Still, there's a hint of hiding behind civilians here I don't particularly like. But I'm just being impractical about the matter. You can't optimize your civilian transmitters to send out signals best for radio detection and ranging, so you lose accuracy. Better than nothing.
  - SiempreViernes 7y ago
    I don't see how its hiding behind civilians? Typically a well marked road march isn't seen as comparable to using human shields, there mere sharing of infrastructure isn't enough.
    - lallysingh 7y ago
      Essentially it's using civilian transmitters as part of a military radar system. A stretch, given.
- mrec 7y ago
  If you want to be extra cheeky, you can use your opponent's radar emitter. https://en.wikipedia.org/wiki/Klein_Heidelberg https://en.wikipedia.org/wiki/Klein_Heidelberg
- m0zg 7y ago
  F22 and F35 themselves have passive radars as well, and can detect stuff without emitting anything. Passive radar is not much more than a phased antenna array without an emitter, you just don't have anything to light up the target with. Once you start emitting you're not stealth anymore, and you can be shot down pretty easily. Same with carrying external ordnance. Same with worn out radar absorbing coating. Same with any physical defects on the plane's surface. That's why these planes are designed to only be stealth in the first few days of a real, actual war, and then once they get scuffed a little by e.g. bullets or debris you're supposed to treat them like regular fighters and not rely on their no longer existent stealth.
vorpalhex 7y ago
So they managed to pick up a stealth jet.. that was equipped with special markers to make it extra visible (for air safety outside of combat), with additional help from a strong polish broadcaster... with information knowing exactly when and where the aircraft would be?
- deleted 7y ago
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- PopePompus 7y ago
  Yes, if the countries deploying the F-35 have any sense at all, they will install equipment to make the aircraft trackable on all air show and most training flights, so that potential adversaries can’t accurately assess their ability to track it in full stealth operation.
- onion2k 7y ago
  Picking it up "with information knowing exactly when and where the aircraft would be" makes it a better test - there's no ambiguity about what they picked up. The important question is whether or not they can pick it up when it doesn't have markers fitted as they claim they can. To quote Carl Sagan, 'extraordinary claims require extraordinary evidence'. If (and it's a huge if) they can do what they say they can then stealth might be rendered pointless, and that changes a lot.
  - _fizz_buzz_ 7y ago
    That quote kind of goes both ways. Claiming that your plane cannot be picked up by any form of radar might be an even more extraordinary claim. In particular Lookhead makes it really hard for anyone to verify this claim. While it seems like Hensoldt was very willing to demonstrate their capabilities at the air show.
- ianhawes 7y ago
  This. It's common knowledge that F-35 and F-22 both fly with markers to ping on radar. Additionally, the fact that the F-35 was squawking their ADS-B indicates that they were not flying in operational mode.
Analemma_ 7y ago
I rant about the F-35 a lot, but seriously: this thing is a trillion-and-a-half dollar shitheap, and this is just the latest proof. What's really damning about this news is that it calls the entire value proposition of the plane into question. By which I mean, every time someone like me points out that the F-35 loses dogfights to planes from two generations ago, the apologists always come in and say that doesn't matter because the stealth and ECM technology means it will never be in dogfights, only BVR engagements. But if you think about, that statement is essentially a gamble. It's a wager that our stealth and ECM technology will always, for the entire 40+ year projected lifespan of the plane, be ahead of competitors. Is that a safe bet? I don't think it is. This news shows it, and that's only what's publicly admissible. Imagine what Russia and China have that they're not talking about. This thing is a piece of junk based on multiple failed ideas (V/STOL, stealth and ECM obsoleting actual combat performance, on-the-fly development, etc.) and it needs to be scrapped yesterday and started from scratch.
- hef19898 7y ago
  I have my doubts about all these 5+ Gen fighters myself. As you said, the planes will fly for 40 years, so it is certain that stealth will be lost sooner or later. And still everybody is developing them. Just looking at the economic side of it, in a war against an enemy with a strong air defense (against ever other enemy stealth doesn't make a difference anyway) exact how many of these planes can you afford to loose without ruining your air force and your economy with it? The F-35 angled at not just its combat capabilities but at a NATO wide domination of combat aircraft, including operations for the full operational life for all operations of these planes. Almost worked out, and my still do.
  - thrower123 7y ago
    It strikes me that having an entire fleet of high stealth aircraft is only going to be important for... maybe the first 48 hours of any conflict. I would suspect that the very first targets in any air war would be radar installations and command and control centers. Once those are down, and air superiority is achieved, stealth doesn't even matter; you could fly B-52 bomb trucks around. Even for that opening stage of the battle, I would suspect that cruise missiles and drones would make more sense.
Caspy7 7y ago
Lies. I've been reassured by the highest authority in the land that this jet is literally invisible.
koube 7y ago
Midway through the article it finally mentions that this was with the "radar invisibility cloak" turned off by installing Luneburg lenses to make it radar visible. I don't doubt that there are current advances in radar technology that weaken the stealth claims of the F-35, but I don't think that this specific case demonstrates this.
- wbl 7y ago
  The lenses are irrelevant to VHF scattering. Civilian air traffic control is S-band, quite a bit up from radio transmissions.
ARandomerDude 7y ago
Misleading. The article says things like the F-35 is "designed to be undetectable by radar." Nothing is designed to be undetectable by "radar." "Stealth" aircraft are designed to be "invisible" (low-observable, really) in one or more radar bands. Once you get outside those EM bands, the aircraft is obviously detectable (e.g., you can see it because your eye doesn't operate in the X band).
- computerex 7y ago
  You are not wrong. But air defense radars operate in specific bands, too. So when articles targeted at laymen use phrases like "designed to be undetectable by radar" - I think they mean that the aircraft is designed to have a small RCS for the bands/radars generally in operation. But of course you are technically right, the jet isn't literally invisible...
  - ARandomerDude 7y ago
    True. The reason I said what I did is because if you have an aircraft that's designed to defeat airborne X band, and somebody on the ground pulls out a truck-mounted radar in a different band, I still wouldn't say the stealth has been defeated, if the reason X band was chosen was to defend against other aircraft. Don't know your background, so I apologize if this is old info for you: the band of radar you use is driven by the size of the antenna, which is why pretty much all fighter radars are X band (maybe +/- a little bit). You only have so much space in the nose of an aircraft, and that becomes a constraint for what radar frequencies you can use. If you know that, and your goal is to not get shot down by enemy fighters, you can optimize your radar signature for that threat. To me, this article is like saying something like "bullet-proof vest defeated by falling boulder." My reaction is well...no...not really....
avalys 7y ago
I wonder if these F35s had external fuel tanks attached, for the long flight back home?
- mannykannot 7y ago
  Excellent question. Embedded within the article is a video of the airplanes arriving in Berlin, and there is no sign of external stores. They might have stopped elsewhere in Europe and removed them there, but a caption on the video describes it as "a record-setting long-duration flight for the F-35 from Arizona" and "an 11-hour flight."
  - angry_octet 7y ago
    It would have been air to air refuelled, the F-35 isn't certified for any type of external tank, though it gets mooted occasionally when someone wants more endurance.
Someone1234 7y ago
This isn't strictly just about a weakness in the F-35's radar resistance, but that the whole concept of "stealth" aircraft may be limited in the future thanks to ever increasing computation power and clever usage of existing radio waves (making effective, passive, "radar" that cannot be easily overcome). But as the article points out, this cannot yet be used for guided missiles, and is very early tech regardless. I suspect the future won't be "super weapons" like the F-35, but instead just "mass" weapons like tens of weaponized drones. Where the mission isn't to be invisible but to simply overwhelming enemy defenses (essentially the World War I strategy, but without the massive numbers of dead soldiers). PS - The people pointing out that the F-35 had radar reflective disks added didn't seem to have understand the article (or technology). This is using entirely different methods to detect the aircraft, not radar waves, so that's irrelevant. The F-35 could be broadcasting a transponder, and it wouldn't undercut the technology discussed.
- ummonk 7y ago
  I should also point out that we do already use mass weapons in the form of cruise missile strikes.
  - Retric 7y ago
    Cruse missiles are really expensive (~1.5 million each) and not really used for mass bombardment. The basic reason to use aircraft/drones is to reuse expensive components like engines and complex sensors.
    - willvarfar 7y ago
      Iranian-made cruise missiles seem super-cheap yet very effective. They also have lots of even-cheaper drones. The Houthi use them to attack oil installations and Patriot batteries. I think the recent attack on the refinery with 18? Drones and 7 cruise missiles (3 fell short?) could be referred to as “bombardment”.
    - openasocket 7y ago
      Time will tell, but I think the answer will depend on the situation. Sure, $1.5M is a lot, but it's able to deliver 400+kg of explosives at a distance of over 1000 km, while cruising at 800+kph at an altitude of 50m. I think any drone you design with those same parameters is going to cost about the same. Now, the re-usability is nice, but that isn't free. For instance, you need to either double the fuel capacity or cut the range in half, since you want your drone to be able to make the return trip. And now you have to worry about the reliability and maintainability of the engine and sensors. Plus, you have to think about survivability of your drone: how many sorties can you expect that drone to go on before it is shot down? Whether you want to use cruise missiles or drone swarms will depend on the increased cost to purchase and maintain drone vs. a cruise missile, and the odds that it will be shot down after dropping the bomb. In a low threat environment where you have air superiority you definitely want drones, but in a high threat environment where you need to penetrate an integrated air defense network, I'm not sure.
hef19898 7y ago
Goes a long with a story I heard last year concerning the presence of a German radar and electronics company at the ILA. The story goes that Lockheed didn't want to fly the F-35 as long as the most advanced radar was on premises. After the radar was moved the F-35 cleared. Also, the radar was set up further away. And the F-35 successfully located. (I wasn't there, so that is a second hand story). EDIT: The Spiegel reports more or less the same story, occurred in Aptil 2018. The radar comes from Hensoldt, a former Airbus subsidiary. And, as already stated in another comment, it was passive radar in the sense it took existing signals and analyzed them and their absence. EDIT 2: Yeah, submitted article reports the same story... Lazy me...
caconym_ 7y ago
I recall that in at least one case an F-35 used for an airshow demonstration had visible deterioration of the stealth material forward of its canopy. It seems that the low-observable systems used by the F-35 are very maintenance-intensive and that the jets used for shows may not be in combat-ready condition. (or, if you prefer, maybe the jets used for demonstrations are intentionally damaged in visible ways so that there is a convenient excuse for the ease of detecting them on radar) edit: I was thinking of the F-22, see comments below for a source. But similar considerations probably apply to the F-35.
- app 7y ago
  I think you are thinking of these recent photos of an F-22: https://www.thedrive.com/the-war-zone/29218/these-images-of-an-f-22-raptors-crumbling-radar-absorbent-skin-are-fascinating https://www.thedrive.com/the-war-zone/29218/these-images-of-... However you're no doubt correct that radar absorbant materials is high maintenance on any aircraft.
  - caconym_ 7y ago
    You're right! Thanks for finding the source.
- bitL 7y ago
  Does F-35 use the same toxic coating as F-22? I believe one could be easily harmed just by touching F-22.
- greedo 7y ago
  Similar considerations do not apply to the F-35. It has a completely different skin coating than the F-22.
  - caconym_ 7y ago
    Different it may be, but I doubt it's maintenance-free. Got a source?
Havoc 7y ago
All comes down to whether the Luneburg lens reflects background noise too. If yes then this is of little use and the result is tainted. If not well that could be a game changer A bit of Google suggests that they are indeed frequency specific see link. So that sounds like it has real potential http://targetsystems.qinetiq.com/static/media/files/Luneberg_Lens_2015.pdf http://targetsystems.qinetiq.com/static/media/files/Luneberg...
- mannykannot 7y ago
  According to that article, the most common use of a Luneberg lens is as a reflector, returning the RF back to its source, and I would guess that is what you would want it to do when your goal is to enhance its visibility to conventional radar. I do not think this would help passive radar, however, even if the lens functions as a retro-reflector at the frequencies used by the passive radar, as the sources and detector are typically a long way apart. These lenses presumably have some isotropic scattering at the frequencies used by this passive radar, and the question is, how much?
ben7799 7y ago
I would be real curious how this passive radar design helps in an actual war environment. Even if you discount all the possible issues like the F-35s not being in "stealth operational mode", having reflectors, etc.. this is not a real world test at all. In the real world test there will be a massive amount of ECM energy hitting this passive radar... it might totally blind a sensor like this. In addition a lot of the civilian radio frequencies/transmitters will be getting knocked offline and it won't have it's energy sources.
- mannykannot 7y ago
  Would active ECM not be a source of illumination of the target that passive radar could take advantage of?
  - inetknght 7y ago
    Sure it would if you also assume that the ECM transmitter is also the target. Decoys might break your assumption though. It seems logical to mount ECM on a decoy target.
    - mannykannot 7y ago
      Passive radar depends on the reflection of ambient RF by the target. A drone radiating for ECM purposes (or any other) might illuminate the airplane it is supposed to be protecting. On the other hand, the algorithms behind passive radar might depend on knowing where the transmitters are. Maybe one could triangulate the drone directly, but not so easily if you have multiple drones transmitting short bursts asynchronously. And if there are enough decoys, it would be like chaff.
      - inetknght 7y ago
        > Passive radar depends on the reflection of ambient RF by the target. A drone radiating for ECM purposes (or any other) might illuminate the airplane it is supposed to be protecting. That's a very good point which I neglected to consider.
Gpetrium 7y ago
In the future, due to advances in radar tech, satellite and others. Skirmishes between highly advanced nations will likely emphasize the use of swarm drones to serve as a battalion and a distraction against the more technically advanced and less defended solutions (e.g. F-35). Whenever someone looks at the F-35 and others, you should aim to build a holistic picture of what 'X' feature serving sub-optimally could entail, not just "Invisibility cloak has weaknesses under these specific conditions, therefore it is a failure" and whether the group behind optimizing the aircraft is aware of it and accounts for that when upgrading and /or sending it on missions.
Merrill 7y ago
Where there are no existing civilian emitters, such as FM stations, it would seem possible to deploy transmitters deliberately to create a hostile RF environment to assist the passive radars.
- LatteLazy 7y ago
  Supposedly, passive radar can use sources as weak and diverse as individual cell phone towers, the GPS system and analogue TV signals. I doubt there is anywhere left on land you couldn't get at least 2 of those signals. Though I'm no expert on the tech and I guess the manufacturer has a big incentive to overstate it.
joyjoyjoy 7y ago
If this is true then this is bad. I always warned that the F35 is a one trick pony. Can't fly fast, can't fly far, can't carry much load, can't dog fight, needs ton of maintenance and may or may not be invisible. By definition, no plane can be invisible. It is a questions of frequencies and angles you look at it. This plane was not build to bomb Syria or Iran. If the German radar can see it, they Russians and Chinese can detect it for sure.
- trhway 7y ago
  > Can't fly fast, can't fly far, can't carry much load, can't dog fight, needs ton of maintenance and may or may not be invisible. that is exactly all the "can't"s the F35 ancestor - Yak-141 [1] - was designed with. All the stealth and quasi-fighter related capabilities of F35 are just bolt-ons onto that design in an attempt to mitigate the "can't"s and to stretch if even just a bit the very limited otherwise capabilities of that design. The only "can" in that design, its raison d'être, was the VTOL with swiveling nozzle (which can't even vector in flight). While that swiveling nozzle is a great thing for a country with no capabilities to build real aircraft carriers, it is a thing born in the pre-stealth age, and thus naturally compromised the stealth (especially in IR) of F35 as there is no way of making it "flat rectangular", like for example on F-22 and B-2, at sane (even by DOD standard) costs. [1] https://www.quora.com/Why-did-Lockheed-Martin-fund-Yak-141/answer/Jones-Averino https://www.quora.com/Why-did-Lockheed-Martin-fund-Yak-141/a...
jorblumesea 7y ago
It's worthwhile to note that while passive radar might be able to detect stealth aircraft, there's not much that can be done other than that. Passive cannot guide missiles, and active radar is the only method used to guide missiles. So even if you detect a squadron of stealth aircraft, what can you do about it?
- HenryKissinger 7y ago
  Scramble your interceptors.
- mannykannot 7y ago
  No doubt there are already missiles in the works that will fly to a given location on internal guidance, and then attempt to home in on a nearby target. As others have pointed out, stealth is not invisibility.
jjoonathan 7y ago
I'm not sure I've ever seen stealth sold as an "invisibility cloak," except by press lacking subject matter familiarity. The pitch I've seen in settings that do have subject matter familiarity is that stealth decreases the detection range for a given power / bandwidth / noise tolerance. Could your opponent use more power? Sure, but then they're easier to missile lock and destroy. Could they use more installations? Sure, but then they have to maintain them and their communications. Could they crank up the sensitivity? Sure, but then they have to deal with false positives and increased vulnerability to jamming. That goes especially for passive radar. Don't get me wrong, it's still an arms race, but it's not as cut-and-dry as this piece would have you believe. Also, it's a VHF technique, which is low enough frequency that I'd bet active cancellation is practical, possibly even through a software update :)
- lm28469 7y ago
  > except by press lacking subject matter familiarity. cough American military propaganda cough
- lambdasquirrel 7y ago
  > Also, it's a VHF technique, which is low enough frequency that I'd bet active cancellation is practical, possibly even through a software update :) A lot of this stuff is literally an arms race, along multiple dimensions. Want to active-cancel the VHF signal? You'll need a transmitter for that. How many can you miniaturize into your fighter, and how many can they fit into the installation on the ground? Another way that it's a race. You have to detect the signal quickly enough and recognize that it's a signal, and then jam it before they can get enough return to discern you from the noise. So there was always a matter of economics/engineering here, and one valid criticism of the F-35 is that it costs a lot for what it's doing, and any way that chips into its advantage (in a way that is actually production-ready, and not just an irreproducible hack) shifts that cost/benefit balance.
  - jjoonathan 7y ago
    Very true, I just want to make sure we aren't taking the "stealth used to be perfect but passive radar makes it mostly useless" claims at face value. Passive radar certainly isn't useless and it does tip the table towards detection. It only tips the table, though. By using ambient RF it is very difficult to track, but very easy to spoof and mess with. How well would it deal with a dozen drones omnidirectionally blasting the star-spangled-banner at high amplitude over FM with a bunch of wacky reverb (and maybe a few leads/lags chosen to look like scattering)? Traditional active radar wouldn't have the slightest problem rejecting interference at that sophistication tier, but most passive radar systems would have a tougher time. As for stealth, > Want to active-cancel the VHF signal? You'll need a transmitter for that. Like antennas in the skin hooked to software radios with resilient analog front ends? To my ears, that sounds like a bet that payed off. > How many can you miniaturize into your fighter A few, probably. That's not enough to do active cancellation at microwave wavelengths, but it might be enough to do active cancellation at VHF. > You have to detect the signal quickly enough and recognize that it's a signal With active radar, that's the game. With VHF passive radar, you characterize the "ambient" radiation, which in this case probably boils down to mapping the FM stations. It's public information, and that is both the greatest strength and the greatest weakness of passive radar.
openasocket 7y ago
Wait, the passive detector was set up only "a couple kilometers" away from the jet? At that range, I'm not surprised you can detect it up with passive radar. You could also detect it with an infrared sensor, a pair of binoculars, or even just listening for the jet engine.
- SiempreViernes 7y ago
  Sure, passive radars need a lot of antennas to cover a lot of ground, but the point is they can be made very hard to find since they are passive and that the hardware doesn't cost so much.
  - openasocket 7y ago
    Definitely, but unless this offers better range than other passive methods (like infrared) this doesn't really change anything.
hindsightbias 7y ago
This is trivial to see. There will be a F-35 demo at Fleet Week in SF this weekend. Turn on your TV to a UHF digital channel during the demo. Watch the interference. Now, it could all be reflectors, but you get a sense how a bistatic RF detector could work.
- dx034 7y ago
  The hard part is probably calculating where the object is and where it's going. With that information, you could then feed the data to IR missiles.
lazyguy2 7y ago
The weakness in F-35's have been well known for a long time now. They've been well known since that a F-117 was shot down in 1999 during the Serbia conflict. The actual event was mostly due to bad operational tactics on the American's side and a very lucky shot, but it did highlight that it was possible to detect stealth fighters using coldwar-era Soviet technology. The problem is that the stealth is specifically geared towards XHF frequencies, which are the frequencies used in radar guided missiles.. which are the favored missiles for the USA. However the planes lack the physical size and features necessary to completely absorb VHF radar. VHF lacks the resolution necessary for guided missiles and VHF radar stations must be very large, but it can be used to monitor air traffic over vast areas. So if you detect a aircraft on VHF and then point your XHF radar at it and nothing shows up... Then you know you are dealing with a USA stealth fighter. Stealth has been heavily oversold to the American public, but foreign governments are not so vulnerable to USA industrial-military propaganda. This doesn't mean that stealth is worthless. It does dramatically reduce chances of detection, just doesn't make them invisible. They are still largely invulnerable to radar-guided missiles. The size of VHF radar arrays needed precludes their use on other aircaft. So to make this sort of thing still requires a sophisticated network connecting large and easily found radar stations, which themselves can be targeted and disrupted in a combat environment. There is still major hurdles needed to solved before it would be possible to actually shoot down these aircraft with radar-guided missiles. Also this technique doesn't work as well against aircraft the size of B-2 bomber.
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- andylynch 7y ago
  I think you may be missing a key point of the system described in the article- it is passive, and does not transmit any signal. Instead it relies on RF already in the environment - radio, tv stations and the like. This makes the system far harder to detect and target. I recall hearing about a similar Chinese(?) system a little while ago which used the scatter from mobile phone signals.
ohiovr 7y ago
Anything made by man can be defeated with enough effort, time, and people.
angry_octet 7y ago
These articles are spectacularly uninformed, jumbling together claims which have never been made, uninfomed guesses and lack of domain expertise. It is more interesting as a propaganda exercise, conceivably so Boeing/Dassault/Saab can sell their planes more competitively, or so the RADAR operator can get more government funding. Problems with the article: - The F35 isn't flown to air shows in 'war mode'. It has a bunch of reflectors added to increase its RADAR signature. It is only naked when it might be used in anger or over test ranges, and the USAF is very careful to make sure non-JSF program RADARs are off, or have the recordings deleted. - Passive RADAR is a real thing that works, but it only gives a general location. It would be meaningless to try to send a link track to an interceptor or SAM site from a passive RADAR system -- all you could do is call and say "look sharp chaps". - When you want to shoot at it, your S band (ground) or X band (interceptor) RADAR will have a very hard time picking it up or maintaining lock (because its signature changes depending on aspect, and obviously the pilot will manoeuvre to minimise). Meanwhile your ground receiver is getting jammed and transmitters are getting blown up by JDAMs. - Passive RADAR can also be jammed and deceived. How many times will you scramble interceptors for a false passive detection?
w0mbat 7y ago
I've been looking for a source, but I remember a previous air show incident where a stealth aircraft was detected and the excuse was that the active stealth system was not turned on, i.e. the aircraft would have used electronic active radar cancellation in addition to stealthy body design if it had been in actual combat. Whether any electronic system would help against passive radar, or would in fact make things worse, is another question.
imtringued 7y ago
For some reason there is the expectation that a new weapon generation is somehow completely infallible and will be able to defeat any future generation. Except new generations of tech make the old generation obsolete. Nothing more nothing less. A non stealth aircraft will have an extremely hard time against a stealth aircraft.
colechristensen 7y ago
This is a big stretch. A radar manufacturer claims they can detect an F-35 which was equipped to be detectable but the radar maker claims that the devices uses to make the plane visible to radar didn't matter because they were tuned to a different frequency. They're just selling radars. The thing about stealth is that a tiny aberration can turn an invisible plane into a flying barn. It doesn't matter if the devices used to make the plane visible were for different bands, it's radio, nothing is exact. They obviously made the plane visible to more than just the target design. On another level, there are various maintenance things that are done to make the plane stealthy when in operation that wouldn't be done going to an airshow. And finally, no one says the F35 is totally invisible to radar in all circumstances. It is especially detectable after it has passed your current position. The value of the stealth is that you don't detect it until it's on top of you or has already fired on you. In a real air-superiority fight, F-22 and whatever other classified drones and planes would be the first wave and clear out a path for the less stealthy but more versatile F-35.
- edoo 7y ago
  Stealth isn't a binary. It is a completely analog range. The stealthier you are the closer you can get to a radar before detection. Even the very stealthy planes are highly visible at relatively close ranges.
doggydogs94 7y ago
Tracking any aircraft, stealth or not, isn't the issue. The issue is whether you can get a weapons grade track.

105 points by XnoiVeX 7y ago

Interesting, apparently it's because of "passive radar" which I'd never heard about before... "Passive radar equipment computes an aerial picture by reading how civilian communications signals bounce off airborne objects." https://en.wikipedia.org/wiki/Passive_radar https://en.wikipedia.org/wiki/Passive_radar

lallysingh 7y ago
I've seen a presentation (over 10 yrs ago) where passive radar was set up as a secondary sensor system that is hard to locate because it's not transmitting. One attack scenario is with a stealth plane first attacking the radar systems, then regular planes come in after. So the passive systems would stay up, as most attacks won't target civilian infrastructure. Still, there's a hint of hiding behind civilians here I don't particularly like. But I'm just being impractical about the matter. You can't optimize your civilian transmitters to send out signals best for radio detection and ranging, so you lose accuracy. Better than nothing.
- SiempreViernes 7y ago
  I don't see how its hiding behind civilians? Typically a well marked road march isn't seen as comparable to using human shields, there mere sharing of infrastructure isn't enough.
  - lallysingh 7y ago
    Essentially it's using civilian transmitters as part of a military radar system. A stretch, given.
mrec 7y ago
If you want to be extra cheeky, you can use your opponent's radar emitter. https://en.wikipedia.org/wiki/Klein_Heidelberg https://en.wikipedia.org/wiki/Klein_Heidelberg
m0zg 7y ago
F22 and F35 themselves have passive radars as well, and can detect stuff without emitting anything. Passive radar is not much more than a phased antenna array without an emitter, you just don't have anything to light up the target with. Once you start emitting you're not stealth anymore, and you can be shot down pretty easily. Same with carrying external ordnance. Same with worn out radar absorbing coating. Same with any physical defects on the plane's surface. That's why these planes are designed to only be stealth in the first few days of a real, actual war, and then once they get scuffed a little by e.g. bullets or debris you're supposed to treat them like regular fighters and not rely on their no longer existent stealth.

vorpalhex 7y ago

So they managed to pick up a stealth jet.. that was equipped with special markers to make it extra visible (for air safety outside of combat), with additional help from a strong polish broadcaster... with information knowing exactly when and where the aircraft would be?

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PopePompus 7y ago
Yes, if the countries deploying the F-35 have any sense at all, they will install equipment to make the aircraft trackable on all air show and most training flights, so that potential adversaries can’t accurately assess their ability to track it in full stealth operation.
onion2k 7y ago
Picking it up "with information knowing exactly when and where the aircraft would be" makes it a better test - there's no ambiguity about what they picked up. The important question is whether or not they can pick it up when it doesn't have markers fitted as they claim they can. To quote Carl Sagan, 'extraordinary claims require extraordinary evidence'. If (and it's a huge if) they can do what they say they can then stealth might be rendered pointless, and that changes a lot.
- _fizz_buzz_ 7y ago
  That quote kind of goes both ways. Claiming that your plane cannot be picked up by any form of radar might be an even more extraordinary claim. In particular Lookhead makes it really hard for anyone to verify this claim. While it seems like Hensoldt was very willing to demonstrate their capabilities at the air show.
ianhawes 7y ago
This. It's common knowledge that F-35 and F-22 both fly with markers to ping on radar. Additionally, the fact that the F-35 was squawking their ADS-B indicates that they were not flying in operational mode.

Analemma_ 7y ago

I rant about the F-35 a lot, but seriously: this thing is a trillion-and-a-half dollar shitheap, and this is just the latest proof. What's really damning about this news is that it calls the entire value proposition of the plane into question. By which I mean, every time someone like me points out that the F-35 loses dogfights to planes from two generations ago, the apologists always come in and say that doesn't matter because the stealth and ECM technology means it will never be in dogfights, only BVR engagements. But if you think about, that statement is essentially a gamble. It's a wager that our stealth and ECM technology will always, for the entire 40+ year projected lifespan of the plane, be ahead of competitors. Is that a safe bet? I don't think it is. This news shows it, and that's only what's publicly admissible. Imagine what Russia and China have that they're not talking about. This thing is a piece of junk based on multiple failed ideas (V/STOL, stealth and ECM obsoleting actual combat performance, on-the-fly development, etc.) and it needs to be scrapped yesterday and started from scratch.

hef19898 7y ago
I have my doubts about all these 5+ Gen fighters myself. As you said, the planes will fly for 40 years, so it is certain that stealth will be lost sooner or later. And still everybody is developing them. Just looking at the economic side of it, in a war against an enemy with a strong air defense (against ever other enemy stealth doesn't make a difference anyway) exact how many of these planes can you afford to loose without ruining your air force and your economy with it? The F-35 angled at not just its combat capabilities but at a NATO wide domination of combat aircraft, including operations for the full operational life for all operations of these planes. Almost worked out, and my still do.
- thrower123 7y ago
  It strikes me that having an entire fleet of high stealth aircraft is only going to be important for... maybe the first 48 hours of any conflict. I would suspect that the very first targets in any air war would be radar installations and command and control centers. Once those are down, and air superiority is achieved, stealth doesn't even matter; you could fly B-52 bomb trucks around. Even for that opening stage of the battle, I would suspect that cruise missiles and drones would make more sense.

Caspy7 7y ago

Lies. I've been reassured by the highest authority in the land that this jet is literally invisible.

koube 7y ago

Midway through the article it finally mentions that this was with the "radar invisibility cloak" turned off by installing Luneburg lenses to make it radar visible. I don't doubt that there are current advances in radar technology that weaken the stealth claims of the F-35, but I don't think that this specific case demonstrates this.

wbl 7y ago
The lenses are irrelevant to VHF scattering. Civilian air traffic control is S-band, quite a bit up from radio transmissions.

ARandomerDude 7y ago

Misleading. The article says things like the F-35 is "designed to be undetectable by radar." Nothing is designed to be undetectable by "radar." "Stealth" aircraft are designed to be "invisible" (low-observable, really) in one or more radar bands. Once you get outside those EM bands, the aircraft is obviously detectable (e.g., you can see it because your eye doesn't operate in the X band).

computerex 7y ago
You are not wrong. But air defense radars operate in specific bands, too. So when articles targeted at laymen use phrases like "designed to be undetectable by radar" - I think they mean that the aircraft is designed to have a small RCS for the bands/radars generally in operation. But of course you are technically right, the jet isn't literally invisible...
- ARandomerDude 7y ago
  True. The reason I said what I did is because if you have an aircraft that's designed to defeat airborne X band, and somebody on the ground pulls out a truck-mounted radar in a different band, I still wouldn't say the stealth has been defeated, if the reason X band was chosen was to defend against other aircraft. Don't know your background, so I apologize if this is old info for you: the band of radar you use is driven by the size of the antenna, which is why pretty much all fighter radars are X band (maybe +/- a little bit). You only have so much space in the nose of an aircraft, and that becomes a constraint for what radar frequencies you can use. If you know that, and your goal is to not get shot down by enemy fighters, you can optimize your radar signature for that threat. To me, this article is like saying something like "bullet-proof vest defeated by falling boulder." My reaction is well...no...not really....

avalys 7y ago

I wonder if these F35s had external fuel tanks attached, for the long flight back home?

mannykannot 7y ago
Excellent question. Embedded within the article is a video of the airplanes arriving in Berlin, and there is no sign of external stores. They might have stopped elsewhere in Europe and removed them there, but a caption on the video describes it as "a record-setting long-duration flight for the F-35 from Arizona" and "an 11-hour flight."
- angry_octet 7y ago
  It would have been air to air refuelled, the F-35 isn't certified for any type of external tank, though it gets mooted occasionally when someone wants more endurance.

Someone1234 7y ago

This isn't strictly just about a weakness in the F-35's radar resistance, but that the whole concept of "stealth" aircraft may be limited in the future thanks to ever increasing computation power and clever usage of existing radio waves (making effective, passive, "radar" that cannot be easily overcome). But as the article points out, this cannot yet be used for guided missiles, and is very early tech regardless. I suspect the future won't be "super weapons" like the F-35, but instead just "mass" weapons like tens of weaponized drones. Where the mission isn't to be invisible but to simply overwhelming enemy defenses (essentially the World War I strategy, but without the massive numbers of dead soldiers). PS - The people pointing out that the F-35 had radar reflective disks added didn't seem to have understand the article (or technology). This is using entirely different methods to detect the aircraft, not radar waves, so that's irrelevant. The F-35 could be broadcasting a transponder, and it wouldn't undercut the technology discussed.

ummonk 7y ago
I should also point out that we do already use mass weapons in the form of cruise missile strikes.
- Retric 7y ago
  Cruse missiles are really expensive (~1.5 million each) and not really used for mass bombardment. The basic reason to use aircraft/drones is to reuse expensive components like engines and complex sensors.
  - willvarfar 7y ago
    Iranian-made cruise missiles seem super-cheap yet very effective. They also have lots of even-cheaper drones. The Houthi use them to attack oil installations and Patriot batteries. I think the recent attack on the refinery with 18? Drones and 7 cruise missiles (3 fell short?) could be referred to as “bombardment”.
  - openasocket 7y ago
    Time will tell, but I think the answer will depend on the situation. Sure, $1.5M is a lot, but it's able to deliver 400+kg of explosives at a distance of over 1000 km, while cruising at 800+kph at an altitude of 50m. I think any drone you design with those same parameters is going to cost about the same. Now, the re-usability is nice, but that isn't free. For instance, you need to either double the fuel capacity or cut the range in half, since you want your drone to be able to make the return trip. And now you have to worry about the reliability and maintainability of the engine and sensors. Plus, you have to think about survivability of your drone: how many sorties can you expect that drone to go on before it is shot down? Whether you want to use cruise missiles or drone swarms will depend on the increased cost to purchase and maintain drone vs. a cruise missile, and the odds that it will be shot down after dropping the bomb. In a low threat environment where you have air superiority you definitely want drones, but in a high threat environment where you need to penetrate an integrated air defense network, I'm not sure.

hef19898 7y ago

Goes a long with a story I heard last year concerning the presence of a German radar and electronics company at the ILA. The story goes that Lockheed didn't want to fly the F-35 as long as the most advanced radar was on premises. After the radar was moved the F-35 cleared. Also, the radar was set up further away. And the F-35 successfully located. (I wasn't there, so that is a second hand story). EDIT: The Spiegel reports more or less the same story, occurred in Aptil 2018. The radar comes from Hensoldt, a former Airbus subsidiary. And, as already stated in another comment, it was passive radar in the sense it took existing signals and analyzed them and their absence. EDIT 2: Yeah, submitted article reports the same story... Lazy me...

caconym_ 7y ago

I recall that in at least one case an F-35 used for an airshow demonstration had visible deterioration of the stealth material forward of its canopy. It seems that the low-observable systems used by the F-35 are very maintenance-intensive and that the jets used for shows may not be in combat-ready condition. (or, if you prefer, maybe the jets used for demonstrations are intentionally damaged in visible ways so that there is a convenient excuse for the ease of detecting them on radar) edit: I was thinking of the F-22, see comments below for a source. But similar considerations probably apply to the F-35.

app 7y ago
I think you are thinking of these recent photos of an F-22: https://www.thedrive.com/the-war-zone/29218/these-images-of-an-f-22-raptors-crumbling-radar-absorbent-skin-are-fascinating https://www.thedrive.com/the-war-zone/29218/these-images-of-... However you're no doubt correct that radar absorbant materials is high maintenance on any aircraft.
- caconym_ 7y ago
  You're right! Thanks for finding the source.
bitL 7y ago
Does F-35 use the same toxic coating as F-22? I believe one could be easily harmed just by touching F-22.
greedo 7y ago
Similar considerations do not apply to the F-35. It has a completely different skin coating than the F-22.
- caconym_ 7y ago
  Different it may be, but I doubt it's maintenance-free. Got a source?

Havoc 7y ago

All comes down to whether the Luneburg lens reflects background noise too. If yes then this is of little use and the result is tainted. If not well that could be a game changer A bit of Google suggests that they are indeed frequency specific see link. So that sounds like it has real potential http://targetsystems.qinetiq.com/static/media/files/Luneberg_Lens_2015.pdf http://targetsystems.qinetiq.com/static/media/files/Luneberg...

mannykannot 7y ago
According to that article, the most common use of a Luneberg lens is as a reflector, returning the RF back to its source, and I would guess that is what you would want it to do when your goal is to enhance its visibility to conventional radar. I do not think this would help passive radar, however, even if the lens functions as a retro-reflector at the frequencies used by the passive radar, as the sources and detector are typically a long way apart. These lenses presumably have some isotropic scattering at the frequencies used by this passive radar, and the question is, how much?

ben7799 7y ago

I would be real curious how this passive radar design helps in an actual war environment. Even if you discount all the possible issues like the F-35s not being in "stealth operational mode", having reflectors, etc.. this is not a real world test at all. In the real world test there will be a massive amount of ECM energy hitting this passive radar... it might totally blind a sensor like this. In addition a lot of the civilian radio frequencies/transmitters will be getting knocked offline and it won't have it's energy sources.

mannykannot 7y ago
Would active ECM not be a source of illumination of the target that passive radar could take advantage of?
- inetknght 7y ago
  Sure it would if you also assume that the ECM transmitter is also the target. Decoys might break your assumption though. It seems logical to mount ECM on a decoy target.
  - mannykannot 7y ago
    Passive radar depends on the reflection of ambient RF by the target. A drone radiating for ECM purposes (or any other) might illuminate the airplane it is supposed to be protecting. On the other hand, the algorithms behind passive radar might depend on knowing where the transmitters are. Maybe one could triangulate the drone directly, but not so easily if you have multiple drones transmitting short bursts asynchronously. And if there are enough decoys, it would be like chaff.
    - inetknght 7y ago
      > Passive radar depends on the reflection of ambient RF by the target. A drone radiating for ECM purposes (or any other) might illuminate the airplane it is supposed to be protecting. That's a very good point which I neglected to consider.

Gpetrium 7y ago

In the future, due to advances in radar tech, satellite and others. Skirmishes between highly advanced nations will likely emphasize the use of swarm drones to serve as a battalion and a distraction against the more technically advanced and less defended solutions (e.g. F-35). Whenever someone looks at the F-35 and others, you should aim to build a holistic picture of what 'X' feature serving sub-optimally could entail, not just "Invisibility cloak has weaknesses under these specific conditions, therefore it is a failure" and whether the group behind optimizing the aircraft is aware of it and accounts for that when upgrading and /or sending it on missions.

Merrill 7y ago

Where there are no existing civilian emitters, such as FM stations, it would seem possible to deploy transmitters deliberately to create a hostile RF environment to assist the passive radars.

LatteLazy 7y ago
Supposedly, passive radar can use sources as weak and diverse as individual cell phone towers, the GPS system and analogue TV signals. I doubt there is anywhere left on land you couldn't get at least 2 of those signals. Though I'm no expert on the tech and I guess the manufacturer has a big incentive to overstate it.

joyjoyjoy 7y ago

If this is true then this is bad. I always warned that the F35 is a one trick pony. Can't fly fast, can't fly far, can't carry much load, can't dog fight, needs ton of maintenance and may or may not be invisible. By definition, no plane can be invisible. It is a questions of frequencies and angles you look at it. This plane was not build to bomb Syria or Iran. If the German radar can see it, they Russians and Chinese can detect it for sure.

trhway 7y ago
> Can't fly fast, can't fly far, can't carry much load, can't dog fight, needs ton of maintenance and may or may not be invisible. that is exactly all the "can't"s the F35 ancestor - Yak-141 [1] - was designed with. All the stealth and quasi-fighter related capabilities of F35 are just bolt-ons onto that design in an attempt to mitigate the "can't"s and to stretch if even just a bit the very limited otherwise capabilities of that design. The only "can" in that design, its raison d'être, was the VTOL with swiveling nozzle (which can't even vector in flight). While that swiveling nozzle is a great thing for a country with no capabilities to build real aircraft carriers, it is a thing born in the pre-stealth age, and thus naturally compromised the stealth (especially in IR) of F35 as there is no way of making it "flat rectangular", like for example on F-22 and B-2, at sane (even by DOD standard) costs. [1] https://www.quora.com/Why-did-Lockheed-Martin-fund-Yak-141/answer/Jones-Averino https://www.quora.com/Why-did-Lockheed-Martin-fund-Yak-141/a...

jorblumesea 7y ago

It's worthwhile to note that while passive radar might be able to detect stealth aircraft, there's not much that can be done other than that. Passive cannot guide missiles, and active radar is the only method used to guide missiles. So even if you detect a squadron of stealth aircraft, what can you do about it?

HenryKissinger 7y ago
Scramble your interceptors.
mannykannot 7y ago
No doubt there are already missiles in the works that will fly to a given location on internal guidance, and then attempt to home in on a nearby target. As others have pointed out, stealth is not invisibility.

jjoonathan 7y ago

I'm not sure I've ever seen stealth sold as an "invisibility cloak," except by press lacking subject matter familiarity. The pitch I've seen in settings that do have subject matter familiarity is that stealth decreases the detection range for a given power / bandwidth / noise tolerance. Could your opponent use more power? Sure, but then they're easier to missile lock and destroy. Could they use more installations? Sure, but then they have to maintain them and their communications. Could they crank up the sensitivity? Sure, but then they have to deal with false positives and increased vulnerability to jamming. That goes especially for passive radar. Don't get me wrong, it's still an arms race, but it's not as cut-and-dry as this piece would have you believe. Also, it's a VHF technique, which is low enough frequency that I'd bet active cancellation is practical, possibly even through a software update :)

lm28469 7y ago
> except by press lacking subject matter familiarity. cough American military propaganda cough
lambdasquirrel 7y ago
> Also, it's a VHF technique, which is low enough frequency that I'd bet active cancellation is practical, possibly even through a software update :) A lot of this stuff is literally an arms race, along multiple dimensions. Want to active-cancel the VHF signal? You'll need a transmitter for that. How many can you miniaturize into your fighter, and how many can they fit into the installation on the ground? Another way that it's a race. You have to detect the signal quickly enough and recognize that it's a signal, and then jam it before they can get enough return to discern you from the noise. So there was always a matter of economics/engineering here, and one valid criticism of the F-35 is that it costs a lot for what it's doing, and any way that chips into its advantage (in a way that is actually production-ready, and not just an irreproducible hack) shifts that cost/benefit balance.
- jjoonathan 7y ago
  Very true, I just want to make sure we aren't taking the "stealth used to be perfect but passive radar makes it mostly useless" claims at face value. Passive radar certainly isn't useless and it does tip the table towards detection. It only tips the table, though. By using ambient RF it is very difficult to track, but very easy to spoof and mess with. How well would it deal with a dozen drones omnidirectionally blasting the star-spangled-banner at high amplitude over FM with a bunch of wacky reverb (and maybe a few leads/lags chosen to look like scattering)? Traditional active radar wouldn't have the slightest problem rejecting interference at that sophistication tier, but most passive radar systems would have a tougher time. As for stealth, > Want to active-cancel the VHF signal? You'll need a transmitter for that. Like antennas in the skin hooked to software radios with resilient analog front ends? To my ears, that sounds like a bet that payed off. > How many can you miniaturize into your fighter A few, probably. That's not enough to do active cancellation at microwave wavelengths, but it might be enough to do active cancellation at VHF. > You have to detect the signal quickly enough and recognize that it's a signal With active radar, that's the game. With VHF passive radar, you characterize the "ambient" radiation, which in this case probably boils down to mapping the FM stations. It's public information, and that is both the greatest strength and the greatest weakness of passive radar.

openasocket 7y ago

Wait, the passive detector was set up only "a couple kilometers" away from the jet? At that range, I'm not surprised you can detect it up with passive radar. You could also detect it with an infrared sensor, a pair of binoculars, or even just listening for the jet engine.

SiempreViernes 7y ago
Sure, passive radars need a lot of antennas to cover a lot of ground, but the point is they can be made very hard to find since they are passive and that the hardware doesn't cost so much.
- openasocket 7y ago
  Definitely, but unless this offers better range than other passive methods (like infrared) this doesn't really change anything.

hindsightbias 7y ago

This is trivial to see. There will be a F-35 demo at Fleet Week in SF this weekend. Turn on your TV to a UHF digital channel during the demo. Watch the interference. Now, it could all be reflectors, but you get a sense how a bistatic RF detector could work.

dx034 7y ago
The hard part is probably calculating where the object is and where it's going. With that information, you could then feed the data to IR missiles.

lazyguy2 7y ago

The weakness in F-35's have been well known for a long time now. They've been well known since that a F-117 was shot down in 1999 during the Serbia conflict. The actual event was mostly due to bad operational tactics on the American's side and a very lucky shot, but it did highlight that it was possible to detect stealth fighters using coldwar-era Soviet technology. The problem is that the stealth is specifically geared towards XHF frequencies, which are the frequencies used in radar guided missiles.. which are the favored missiles for the USA. However the planes lack the physical size and features necessary to completely absorb VHF radar. VHF lacks the resolution necessary for guided missiles and VHF radar stations must be very large, but it can be used to monitor air traffic over vast areas. So if you detect a aircraft on VHF and then point your XHF radar at it and nothing shows up... Then you know you are dealing with a USA stealth fighter. Stealth has been heavily oversold to the American public, but foreign governments are not so vulnerable to USA industrial-military propaganda. This doesn't mean that stealth is worthless. It does dramatically reduce chances of detection, just doesn't make them invisible. They are still largely invulnerable to radar-guided missiles. The size of VHF radar arrays needed precludes their use on other aircaft. So to make this sort of thing still requires a sophisticated network connecting large and easily found radar stations, which themselves can be targeted and disrupted in a combat environment. There is still major hurdles needed to solved before it would be possible to actually shoot down these aircraft with radar-guided missiles. Also this technique doesn't work as well against aircraft the size of B-2 bomber.

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andylynch 7y ago
I think you may be missing a key point of the system described in the article- it is passive, and does not transmit any signal. Instead it relies on RF already in the environment - radio, tv stations and the like. This makes the system far harder to detect and target. I recall hearing about a similar Chinese(?) system a little while ago which used the scatter from mobile phone signals.

ohiovr 7y ago

Anything made by man can be defeated with enough effort, time, and people.

angry_octet 7y ago

These articles are spectacularly uninformed, jumbling together claims which have never been made, uninfomed guesses and lack of domain expertise. It is more interesting as a propaganda exercise, conceivably so Boeing/Dassault/Saab can sell their planes more competitively, or so the RADAR operator can get more government funding. Problems with the article: - The F35 isn't flown to air shows in 'war mode'. It has a bunch of reflectors added to increase its RADAR signature. It is only naked when it might be used in anger or over test ranges, and the USAF is very careful to make sure non-JSF program RADARs are off, or have the recordings deleted. - Passive RADAR is a real thing that works, but it only gives a general location. It would be meaningless to try to send a link track to an interceptor or SAM site from a passive RADAR system -- all you could do is call and say "look sharp chaps". - When you want to shoot at it, your S band (ground) or X band (interceptor) RADAR will have a very hard time picking it up or maintaining lock (because its signature changes depending on aspect, and obviously the pilot will manoeuvre to minimise). Meanwhile your ground receiver is getting jammed and transmitters are getting blown up by JDAMs. - Passive RADAR can also be jammed and deceived. How many times will you scramble interceptors for a false passive detection?

w0mbat 7y ago

I've been looking for a source, but I remember a previous air show incident where a stealth aircraft was detected and the excuse was that the active stealth system was not turned on, i.e. the aircraft would have used electronic active radar cancellation in addition to stealthy body design if it had been in actual combat. Whether any electronic system would help against passive radar, or would in fact make things worse, is another question.

imtringued 7y ago

For some reason there is the expectation that a new weapon generation is somehow completely infallible and will be able to defeat any future generation. Except new generations of tech make the old generation obsolete. Nothing more nothing less. A non stealth aircraft will have an extremely hard time against a stealth aircraft.

colechristensen 7y ago

This is a big stretch. A radar manufacturer claims they can detect an F-35 which was equipped to be detectable but the radar maker claims that the devices uses to make the plane visible to radar didn't matter because they were tuned to a different frequency. They're just selling radars. The thing about stealth is that a tiny aberration can turn an invisible plane into a flying barn. It doesn't matter if the devices used to make the plane visible were for different bands, it's radio, nothing is exact. They obviously made the plane visible to more than just the target design. On another level, there are various maintenance things that are done to make the plane stealthy when in operation that wouldn't be done going to an airshow. And finally, no one says the F35 is totally invisible to radar in all circumstances. It is especially detectable after it has passed your current position. The value of the stealth is that you don't detect it until it's on top of you or has already fired on you. In a real air-superiority fight, F-22 and whatever other classified drones and planes would be the first wave and clear out a path for the less stealthy but more versatile F-35.

edoo 7y ago
Stealth isn't a binary. It is a completely analog range. The stealthier you are the closer you can get to a radar before detection. Even the very stealthy planes are highly visible at relatively close ranges.

doggydogs94 7y ago

Tracking any aircraft, stealth or not, isn't the issue. The issue is whether you can get a weapons grade track.