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by natermer 2515 days ago
No. Not a F-22 or F-35 are unlikely to actually be invisible. A B-2 bomber has a better chance.

The talking heads from the military may talk about 'invisibility', but they are full of shit. Just propaganda for the tax payer.

The problem is the physical size of the jet. In order to absorb the radar the material needs to be the proper size in relation to the wavelength. A B-2 bomber is large enough to absorb useful radar frequencies, but F-35 or F-22 isn't.

What the F-35/F-22 stealth does get, however, is invisibility in the XHF and higher frequency ranges, which is what is used for radar guided missiles. So they will have a major advantage against ground and air launched long range missiles.

The F-22 also has good infrared suppression, which protects it against infrared guided missiles. F-35s have a large IR signature, so they are probably not much better then other US jets. Traditionally speaking it's IR weapons that have caused losses for USA airplanes in modern times.

At VHF and lower frequencies the F-22 and F-35 can be detected, but those radars don't offer enough resolution to make them particularly useful for missiles. People suspect that with multiple angles and computer algorithms it may be possible to target a jet that way, but who knows.

So if you were Russia and you detected something with VHF long range radar and then you pointed a shorter range XHF radard at it... and nothing shows up then you can be reasonably certain that it's a American stealth fighter jet. That doesn't mean they can do much about it, though.

To combat this it is suspected that Americans use a technique that involves 'ghosting' commercial airliner traffic to mask the signatures of their jets against the lower frequency, longer range, radar.

6 comments

> Americans use a technique that involves 'ghosting' commercial airliner traffic

You mean flying under commercial traffic? That's what was likely the cause of French jets downing a civilian plane over Italy in 1980 - while trying to hit a Lybian MIG "hidden" under it. Reportedly, Lybian planes routinely did that in order to reach their servicing bases in Yugoslavia.

> That's what was likely the cause of French jets downing a civilian plane over Italy in 1980

Note that the event is heavily disputed. The British Air Accidents Investigation Board claims that a missile strike does not match the wreckage analysis; instead stating a explosive device in the rear bathroom was the only possible cause.

It’s disputed, but shouldn’t be. The third investigation pretty conclusively showed it was a bomb placed under the wash basin in the rear lavatory.

The missing body parts near the front of the plane suspected to be the missile impact point were found.

It's highly disputed because the original allegation is not just France, but rather a French-led NATO joint force that included Britain. It's assumed that the British investigation can't be trusted.

The other investigations also doesn't explain the wreckage of a Libyan fighter jet, close to the wreckage of the airliner.

Multiple Italian soldiers were also found guilty of concealing evidence about the event, allegedly by the request of NATO.

Investigations from NATO sources simply cannot be trusted. They are not independent. The only supporters of the bomb scenario left, in Italy, are ultra-right-wing people who refuse to accept the fact that Italian autorities of the time lied.

It was even admitted by the Italian then-PM (later President) Francesco Cossiga, almost 30 years later, that he was told right away it had been a French jet. This was confirmed later by multiple sources, among them a retired US seaman who was stationed on the Saratoga and feared for his life (a lot of key witnesses have died in suspicious circumstances, including suicide). And the secret-war scenario is the only one that can explain a Lybian MIG crashing in the same area on the same day, which was kept hidden for weeks by Italian authorities.

The historical truth has basically been ascertained, it will simply never be admitted by the involved parties because it is still inconvenient (Lybia still being "in play" between France and Italy).

I did not know about this case, but good luck to the justice to know the truth. It might be a french or american airplane according to wikipedia. The french army is called in France "la grande muette" for a reason: it never speaks or admits anything (e.g. Bugaled Breizh ship).

American also used this technique to fly military aircraft above french airspace while France was not part of NATO, it is only in 2007 with Sarkozy that France entered NATO (one of his many stupid move if you ask me)

France was always a member state of NATO since 1949. France was just not taking part in the integrated military command between the mid-60's to 2007, but did participate in all NATO mission (for instance Afghanistan, Bosnia, Serbia, etc.).
Indeed French authorities actively obstructed the search for truth over the decades, but to be fair, Italian and American authorities did exactly the same (or worse). Nobody wants to admit letting it happen, even if it was a mistake.
MH-17, anyone?
> The talking heads from the military may talk about 'invisibility', but they are full of shit. Just propaganda for the tax payer.

I think a distinction needs to be made between proverbial "invisibility" and stealth, and the technical definition. If general conversations included, say, backscatter coefficients you'd start seeing glazed eyes. Or perhaps area equivalence (square-footage? square-metrage?).

> The problem is the physical size of the jet.

Also: vertical stabilizers.

Stabilizers on these fighter jets are heavily canted, aren't they?
Yes, but that merely limits the damage to a small degree. Fighters need vertical stabilizers because they require higher maneuverability than flying wings. And current aerospace design capabilities can't overcome it, though bendable (wing warping technology) wings might eventually.
Boeing's vaporware proposal for a 6G fighter has no VSes:

* https://en.wikipedia.org/wiki/F/A-XX_Program

Yup, thrust vectoring will help add control authority. But vertical stabilizers don't necessarily contribute to the amount of G's an aircraft can pull. It depends on how they're measuring it. With an aircraft lacking VS, you could simply pull/push up down to get high G, or roll and do the same.

    To combat this it is suspected that Americans use a
    technique that involves 'ghosting' commercial airliner
    traffic to mask the signatures of their jets against 
    the lower frequency, longer range, radar. 
That sounds fascinating. A quick Googling bore no fruit for me. Can you elaborate, or point me in the direction of more information?
They can change their radar signature since the true signature isn't much of anything. They can mimic the signature of other planes and even move the signature making it seem like the spoofed aircraft is closer or further away than it really is. If you move the spoofed signature much closer to a radar installation, they might fire off a missile from another location that was previously hidden. Make the spoofed signature large enough and they may not see the anti-radiation missile heading towards them. There are also expendable versions of this tech that can be dropped from a plane like chaff, further increasing the distance between the spoofed signature and the true one.

https://en.wikipedia.org/wiki/Digital_radio_frequency_memory

https://www.militaryaerospace.com/computers/article/16726118...

https://www.c4isrnet.com/electronic-warfare/2019/05/15/can-n...

Its a cat and mouse game between airplanes and radars.

Radars are usually arrays of small radars now that can move the beam without even moving, chirp the frequecy and do all sorts of weird things. I wrote OS software to help control them years ago, which was interesting.

http://www.radartutorial.eu/02.basics/Stepped%20Chirp%20Rada...

its an interesting exercise in signal processing. there are lots of books on the subject: And hey! my radar made a cover.

https://www.amazon.com/s?k=radar&i=stripbooks&ref=nb_sb_noss

I think radar is absolutely fascinating. I work in a different RF field but sometimes I wish I got drawn into that instead.
Fascinating. Thanks!
Israel in fact recently did this in Syria and succesfully targeted the Russian S200 and S300 systems.

https://www.bbc.com/news/world-europe-45556290

> So if you were Russia

A much more probable scenario would be of its airfield being blown up by something like Tochka or Luna even before most of the planes will have a chance to sortie.

This is why there is a natural scepticism of airforce centric warfare: a tank will not fall out of the sky the moment its logistic supply is cut.

According to Wikipedia, most recently shot down aircraft have been helicopters falling to small arms, or course Wikipedia is dependent on what people write, but as far as I can tell there aren't that many jets being shot down by IR missiles.

Unless that is your point of course

https://en.wikipedia.org/wiki/List_of_aircraft_shootdowns#Ir...

USA hasn't really fought people capable of shooting down jets in a while. So the latest is generally the early 1990's with the combat in Iraq.

The only stealth plane shot down that I am aware of was a F-117 shot down by short range SAM in the Kosovo war in 1999. It was a older 1960's missile design. Probably due to a large part of combination of dumb luck on the side of the SAM operator and the Airforce being lazy and having the jet fly predictable routine routes.

Definitely some dumb luck - they managed to catch it with the bomb bay doors open, which increased its radar signature dramatically.
I wouldn't call that 'luck' per se on account of the Americans apparently flying like that habitually, as well as sticking to predictable flight plans. It's not like the Serbs fired into the blue on a whim and were shocked when they hit something.
Yeah, highlights issue of being so damn good, you get complacent
That's the lazy part.
It was not dumb luck. He placed his site where he knew the doors were more likely to be open and hence increase the signature, and waited for that moment to switch on the radar and fire the shot.
Most recent combat environments (Iraq war post-invasion, and Afghanistan) were not contested air space. The US has always had air superiority over those regions and the ability to fly AWACS planes, Predators, Reapers, Global Hawks and a whole bunch of other stuff around with very little risk of getting shot down.

Aircraft operating low to the ground and on approach to small airfields, and helicopters, are of course vulnerable to short range rifle fire and MANPADs. There have been losses to that in Afghanistan.

Modern NATO-equipped militaries haven't really encountered a semi modern air defense system since the brief bombing campaign against Serbia, in which they did manage to lose a F117 to a SAM.

Interesting how many of the fixed-wing shootdowns since the Gulf War were shot down by equipment made by the same geopolitical block (either NATO-on-NATO or Soviet-on-Soviet), either in the sense of literal friendly-fire accidents, or two regional combatants both being supplied by the same superpower. Turkish F-16 shot down by Greek Mirage 2000. British Tornado shot down by U.S. Patriot. A-10 shot down by Iraqi Roland. Georgian Hermes-450 shot down by Russian Mig-29. Russian Tu-22 shot down by Georgian Buk-M1. Ukrainian Su-27 shot down by Russian Su-27. Ukrainian Mig-29 shot down by Buk. That's practically all of the combat jets on the list.
That may just be a factor of modern warfare being largely one side with near-absolute air superiority in an area pounding on largely defenseless ground troops.

The first Gulf War saw nearly half of coalition casualties being from friendly fire.