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Comment by HelloNurse | Hacker News Reader

What makes this article look like a PR piece, more than the smiles, is the appearance of a firm directive to talk about situational awareness etc. instead of flight performance and the clear defensive intent of some sections (e.g. the airshow demo).

There seem to be a large blind spot in these pilot accounts, some elephant in the room, but not being an expert I'm unable to pinpoint what it is.

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> There seem to be a large blind spot in these pilot accounts, some elephant in the room, but not being an expert I'm unable to pinpoint what it is.

I'm not an expert either. But I suspect it might be one of the following:

1. the F-22 has a higher thrust to weight ration than the F-35, meaning the F-22 is more manouvrable.

2. the F-22 has a lower wing loading than the F-35, again making the F-22 more manouvrable.

3. the stealth on the F-35, while good against the radars of 20 years ago, might be a lot less effective against the radars of the future, for example long-wavelength radars with lots of ground-based sensors all tied together with sensor fusion. This is a big deal since the F-35 is expected to stay in service until 2070 and I'm sure the Chinese and Russians are looking at ways to counter it.

I though stealth as a concept was near obsolete due to cheap passive radar becoming feasible for about everyone? I didnt know they still built planes for this concept.

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

Stealth is relative; as long as your detection distance is greater than the adversary's, you're good. Also, passive is great, but I'd expect in a war situation all large transmitters would get disabled first.

All cellphone towers?

You don't have to worry about most small cell towers, since they are usually directional (pointed towards the ground to maximize signal coverage) and relatively low power. In the countryside with tall towers that cover tens of kilometers... well... it's kind of hard to miss those with a missile.

You can always mount the transmitters in trucks and keep moving. If you can pinpoint the source and fuse the input of, say, dozens of small sensors deployed all over the place, you can pinpoint the plane well enough.

Not well enough to do reliably do missile tracking, just enough to get an idea that yes, there is an object out there in the atmosphere. "Dumb" methods like TDOA / FDOA have quite bad limitations on resolution.

Multistatic passive radar is quite hard to do at high performance. Radio astronomy observatories have been doing it for decades; it's expensive, requires high grade equipment to synchronize time and frequency, and reliable, real-time high-bandwidth data links.

You can use passive radar for surveillance radars, but is it any good for tracking and guidance radars? If your radar stations can see F-35s, but your interceptors and SAM batteries can't fire at it, the stealth is still useful.

That's getting awfully ahead of things. Showing that it's sometimes possible to detect aircraft like this is a long, long way from demonstrating that it's even theoretically possible to replace all existing air defense and targeting/interception radars with it under all circumstance, much less actually trying to do it.

On the subject of stealth, I've always wondered if stealth aircraft could not actually be detected fairly easily.

True, stealth aircraft have an extremely small radar cross-section. But I'm guessing they also have very specific and recognizable radar signatures, with the proper signal treatment, despite high noise ratios, their signatures could be isolated. And they could also be easily identified down to the variant of aircraft.

This is a pure guess, not substantiated by anything, and I'm far from an expert or even an enthusiast in the field.

I think it's less "you will NEVER see me on Radar" but more "Radar detection range reduced from 100 miles to 40 miles", meaning you have more gaps in your coverage than you expected, and also they can get a lock on you before you get a lock on them.

As far as points 1 and 2, the F-22 was designed to shoot down other planes. The F-35 was designed for a large variety of roles. As far as point 3, that's a tough one. Nobody truly knows what detection technology will be like in 20 years. You may be right and the tech is obsolete quickly.

That the F-35bis a compromise designed for several sorts of missions it itself a criticism: it might not succeed at any.

(and let me be clear; I’m a pacifist... putting all the money spent on weapons into increasing interdependence is a much more effective strategy. You don’t want to level your debtors/creditors.

> and let me be clear; I’m a pacifist... putting all the money spent on weapons into increasing interdependence is a much more effective strategy. You don’t want to level your debtors/creditors

Lots of people want to level their creditors. Economic interdependence didn't prevent the World Wars--to some degree, it exacerbated them because some countries (e.g. Germany and Japan) had strategic reasons to secure their supply of natural resources.

Some clever/lucky Serbian back in the Kosovan conflict days realised that even then-old low frequency radar was able to pinpoint the F117s making nightly passes over their country, helping bring one down.

Given that was nearly twenty years ago and we've since had massive advances in passive and synthetic aperture radar otherwise, I've long wondered about the worth of the massive extra cost stealth brings to Fifth Generation warplanes.

Given the Russians don't appear to be in a great rush to make all their wares stealthy, one wonders whether they've preëmpted its limited use in future?

The Russians aren't in a great rush to acquire anything new because they're simply short of cash. People seem to forget that Russia's GDP is about the same size as Italy. After they pay for their strategic nuclear forces there's not much room in the budget for anything else.

Sure, but they do have a healthy export market for their armaments...

Russia's remaining arms customers are mostly poor and desperate. They can't afford 5G aircraft. India used to be a major customer but now that they have more money they're shifting purchases to better alternatives.

The F117 was 70's tech. It looked like a weird polyhedron because we didn't have good enough computers to do the math on how the shape of a plane reflects radar. And it was only shot down because the bomb bay doors weren't stealthy.

There's no free lunch in radar. Long wavelength radars can give a general indication of an aircraft's location but aren't precise enough for targeting. They're also more subject to interference. And the antennas are larger, which makes them more vulnerable.

The F-22 is out of production and there's no practical way to build more. So regardless of its comparative merits it's not an alternative.

> The F-22 is out of production and there's no practical way to build more.

Lockheed Martin have all the manufacturing equipment in storage and have been trying to sell the Pentagon and others on the idea of restarting the production line to build more F22s with upgraded avionics/electronics taken from the F35. To offset the cost of restarting production they propose allowing Japan to buy them too since Japan has been keen on buying them for a long time.

Actually the tooling is owned and possessed by the USGov, not LM. And restarting the production line isn't as simple as flipping a switch. You'd need all the components made by subcontractors (that are out of business). And you'd also need to find assembly workers familiar with the processes involved in fabricating the airframes etc. Plus the technology is OLD. The avionics are old, 1980/1990 designed systems. So you'd naturally want to upgrade it to the latest standards, which would cost more money and extend the time required to deliver a plane to the AF.

What you're saying about long wave is true for monostatic radar where you're using the angle of the beam to localize the target. In the multistatic case, you don't need to do this, it can be all timing based. This wasn't possible in the past because we didn't have the ability to easily synchronize clocks to high precision and the computers and communication technology to easily fuse the results. We do now though.

That's more of a theoretical possibility than something that can be used operationally today.

It's a bit more than a theoretical possibility. 5G requires cooperative MIMO. If you can do cooperative MIMO, you can build the type of radar I'm describing. I don't have insider knowledge, but this is something that has been openly talked about for over twenty years. I'd be shocked if someone doesn't have at least a working test system.

You don't have to guess at #1 and #2. One of the pilots came right out and said it: "The F-35 is as maneuverable as any other airplane, except perhaps the F-22."

I noted the "we don't need to make the three versions identical" comment.

Yeah, you kinda do, if you want to keep the price of an individual airframe down.

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