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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 h

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.
- velox_io 7y ago
  It's quite a change going from not exporting any F22s to the F35s, which feels like they'll sell them to anyone that wants some (minus the usual suspects). Especially when the F35s stealth technology is said to be more advanced. It's hard to get your head around a plane the can climb over 1000 feet per second (F22: 62,000ft in 60 seconds).
russdill 7y ago
For those not in the know: https://www.businessinsider.com/f-35-luneberg-radar-cross-section-russia-estonia-2017-5 https://www.businessinsider.com/f-35-luneberg-radar-cross-se...
upofadown 7y ago
The radar people claim that the "markers" intended for microwave frequencies would make no difference to passive radar. That seems quite believable as passive radar uses things like commercial VHF radio transmitters as emitters. The frequencies involved are vastly different. The features are simply too small to cause much of a reflection at VHF.
- ltbarcly3 7y ago
  So... Microwave and VHF are not vastly different frequencies, Microwave starts at 300MHz and VHF ends at ... 300MHz. Yes, they each span a wide range of frequencies, but every frequency range spans a wide range of frequencies. These two are as close as you can be. https://en.wikipedia.org/wiki/Microwave https://en.wikipedia.org/wiki/Microwave https://en.wikipedia.org/wiki/Very_high_frequency https://en.wikipedia.org/wiki/Very_high_frequency Not coincidently, VHF Radar is defined to be between 50 and 330Mhz, which actually overlaps both Microwave and VHF television. Now as to the main question, if I set up a device to interact with radar at some frequency and attach it to a stealth airplane, what frequencies would you expect it to effectively interact with it (assuming it's tuned at all, they could just be attaching a big piece of flat aluminum)? Answer: If my device has peak interaction at frequency F, you will see harmonics, so you will see significant interactions at 1/8 F, 1/4 F, 1/2 F, F, 2 F, 4F, 8F. Airport radar is around 3Ghz. So if the radar reflector operates at around 3Ghz, it will also work pretty well at 1.5Ghz, 750Mhz, 375Mhz, and even 187.5 Mhz. 187.5Mhz is TV channel 6 or 7, depending on country. Half again is 93.7 is FM (which the article specifically mentions).
  - SiempreViernes 7y ago
    More importantly, how does the intensity go with the order of the harmonics?
    - ltbarcly3 7y ago
      I don't know enough about the reflector. If it works like a boat's radar reflector, an 20 cm reflector would have a equivalent cross section as a metal sphere with an area of about 30 square meters. I mean the goal of a radar reflector is to send radar signals back to their source, they are super effective. They don't really work like antennas generally, but the pictures of the F-35's reflectors do not look typical, or like a boat's radar reflector, and I have no idea what principle they use.
burnte 7y ago
Exactly. It was tracked with radar reflectors to make it visible, and from a position they knew the jets would be close, while also tracking their transponders to correlate with the reflection data. This is the equivalent of saying they successfully completed the Daytona 500 by driving a Honda around the track a few times at 45 miles an hour with the track closed to everyone else.
braythwayt 7y ago
This was addressed in the OP. Their explanation is that the markers are optimized for the specific band of civilian radar, and that they do not assist with passive radar detection. As for knowing when and where the planes were flying, true, true. But then again, they deployed one van to try to detect the planes, in the one farm, and if the objective was to suggest that the passive technology could end up being useful in a military situation, that might be enough. The argument is that the F-35 is invisible. If passive detection seems to have any effectiveness, even slight, in detecting F-35s, that ought to guide investment into passive detection and into upgrading the F-35’s stealth to avoid passive detection. INAE, but it feels like there is enough here to cast the claims of complete invulnerability to detection in doubt.
- akvadrako 7y ago
  The main argument for the F-35's stealth is to avoid target locking missiles. It's not to be "invisible".
  - SiempreViernes 7y ago
    How does low radar observatbility help against IR missiles?
    - 0003 7y ago
      IR is only really effective in the short-range (see an aim-9 which is only effective less than 20 nm (really less than that practically speaking). When they talk about this, they mean protection against beyond visual range missiles.
      - hguant 7y ago
        >(see an aim-9 which is only effective less than 20 nm (really less than that practically speaking) I would really love to see the actual Probability of Kill numbers for the US missile fleet. I know that's never going to happen/they're going to remain classified for a _long_ time, but the kid in me really wants to know "does it actually work?"
bayesian_horse 7y ago
Those markers may actually be irrelevant for the tracking, because they are very small and are meant for different frequencies. ADS-B also doesn't come into it, if they designed the system or demonstration correctly. More interesting would be whether those planes actually had the full stealth coating and various other "stealth settings".
deleted 7y ago
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freeone3000 7y ago
It was also actively broadcasting its location at the time.

deleted 7y ago

[deleted]

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.

velox_io 7y ago
It's quite a change going from not exporting any F22s to the F35s, which feels like they'll sell them to anyone that wants some (minus the usual suspects). Especially when the F35s stealth technology is said to be more advanced. It's hard to get your head around a plane the can climb over 1000 feet per second (F22: 62,000ft in 60 seconds).

russdill 7y ago

For those not in the know: https://www.businessinsider.com/f-35-luneberg-radar-cross-section-russia-estonia-2017-5 https://www.businessinsider.com/f-35-luneberg-radar-cross-se...

upofadown 7y ago

The radar people claim that the "markers" intended for microwave frequencies would make no difference to passive radar. That seems quite believable as passive radar uses things like commercial VHF radio transmitters as emitters. The frequencies involved are vastly different. The features are simply too small to cause much of a reflection at VHF.

ltbarcly3 7y ago
So... Microwave and VHF are not vastly different frequencies, Microwave starts at 300MHz and VHF ends at ... 300MHz. Yes, they each span a wide range of frequencies, but every frequency range spans a wide range of frequencies. These two are as close as you can be. https://en.wikipedia.org/wiki/Microwave https://en.wikipedia.org/wiki/Microwave https://en.wikipedia.org/wiki/Very_high_frequency https://en.wikipedia.org/wiki/Very_high_frequency Not coincidently, VHF Radar is defined to be between 50 and 330Mhz, which actually overlaps both Microwave and VHF television. Now as to the main question, if I set up a device to interact with radar at some frequency and attach it to a stealth airplane, what frequencies would you expect it to effectively interact with it (assuming it's tuned at all, they could just be attaching a big piece of flat aluminum)? Answer: If my device has peak interaction at frequency F, you will see harmonics, so you will see significant interactions at 1/8 F, 1/4 F, 1/2 F, F, 2 F, 4F, 8F. Airport radar is around 3Ghz. So if the radar reflector operates at around 3Ghz, it will also work pretty well at 1.5Ghz, 750Mhz, 375Mhz, and even 187.5 Mhz. 187.5Mhz is TV channel 6 or 7, depending on country. Half again is 93.7 is FM (which the article specifically mentions).
- SiempreViernes 7y ago
  More importantly, how does the intensity go with the order of the harmonics?
  - ltbarcly3 7y ago
    I don't know enough about the reflector. If it works like a boat's radar reflector, an 20 cm reflector would have a equivalent cross section as a metal sphere with an area of about 30 square meters. I mean the goal of a radar reflector is to send radar signals back to their source, they are super effective. They don't really work like antennas generally, but the pictures of the F-35's reflectors do not look typical, or like a boat's radar reflector, and I have no idea what principle they use.

burnte 7y ago

Exactly. It was tracked with radar reflectors to make it visible, and from a position they knew the jets would be close, while also tracking their transponders to correlate with the reflection data. This is the equivalent of saying they successfully completed the Daytona 500 by driving a Honda around the track a few times at 45 miles an hour with the track closed to everyone else.

braythwayt 7y ago

This was addressed in the OP. Their explanation is that the markers are optimized for the specific band of civilian radar, and that they do not assist with passive radar detection. As for knowing when and where the planes were flying, true, true. But then again, they deployed one van to try to detect the planes, in the one farm, and if the objective was to suggest that the passive technology could end up being useful in a military situation, that might be enough. The argument is that the F-35 is invisible. If passive detection seems to have any effectiveness, even slight, in detecting F-35s, that ought to guide investment into passive detection and into upgrading the F-35’s stealth to avoid passive detection. INAE, but it feels like there is enough here to cast the claims of complete invulnerability to detection in doubt.

akvadrako 7y ago
The main argument for the F-35's stealth is to avoid target locking missiles. It's not to be "invisible".
- SiempreViernes 7y ago
  How does low radar observatbility help against IR missiles?
  - 0003 7y ago
    IR is only really effective in the short-range (see an aim-9 which is only effective less than 20 nm (really less than that practically speaking). When they talk about this, they mean protection against beyond visual range missiles.
    - hguant 7y ago
      >(see an aim-9 which is only effective less than 20 nm (really less than that practically speaking) I would really love to see the actual Probability of Kill numbers for the US missile fleet. I know that's never going to happen/they're going to remain classified for a _long_ time, but the kid in me really wants to know "does it actually work?"

bayesian_horse 7y ago

Those markers may actually be irrelevant for the tracking, because they are very small and are meant for different frequencies. ADS-B also doesn't come into it, if they designed the system or demonstration correctly. More interesting would be whether those planes actually had the full stealth coating and various other "stealth settings".

deleted 7y ago

[deleted]

freeone3000 7y ago

It was also actively broadcasting its location at the time.