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Czech Passive Radar Detecting B-2 at 150 miles (2015)

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Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#21

Post by Retric »

lazyjones wrote: post #7

What would air defence against a swarm of a few 1000 UAV look like? Because China...

Drones represent a huge range of different things. Assuming you mean something that’s a replacement for military aircraft.

In order to have a useful X,000miles range and useful payload you need to build fairly large drones which means a large target. If their cheap that directly translates into low speeds making them a very easy target for anti air guns, or low cost anti aircraft missiles.

If you want a large fast drone, that’s getting expensive. To the point where having or not having a pilot makes minimal cost differences.

Note, this assumes it’s part of a modern war with extreme radio jamming etc.

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#22

Post by wbl »

whalesalad wrote: post #3

The B2 is relatively ancient as far as stealth tech goes. Also, most stealth aircraft are detectable on radar. The question is how big or small is the radar cross section. That’s not something this blog post digs into. Meaning, most of the time a B2 looks like a goose or a small animal. Correction on my part: The B-2 and F-35 have radar cross sections roughly the size of a marble.

Geese don't go supersonic.

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#23

Post by rblatz »

Retric wrote: post #21
lazyjones wrote: post #7

What would air defence against a swarm of a few 1000 UAV look like? Because China...

Drones represent a huge range of different things. Assuming you mean something that’s a replacement for military aircraft. In order to have a useful X,000miles range and useful payload you need to build fairly large drones which means a large target. If their cheap that directly translates into low speeds making them a very easy target for anti air guns, or low cost anti aircraft missiles. If you want a large fast dr…

Why would you not deploy smaller drones via another platform?

Small cheap disposable drones are a game changer. Drop them on a military base and have them seek and distort any human shaped targets, any sources of RF radiation, anything that looks like a vehicle or plane...

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#24

Post by berkut »

wbl wrote: post #22
whalesalad wrote: post #3

The B2 is relatively ancient as far as stealth tech goes. Also, most stealth aircraft are detectable on radar. The question is how big or small is the radar cross section. That’s not something this blog post digs into. Meaning, most of the time a B2 looks like a goose or a small animal. Correction on my part: The B-2 and F-35 have radar cross sections roughly the size of a marble.

Geese don't go supersonic.

Neither does the B2...

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#25

Post by KingOfCoders »

I think the current anti stealth capabilities are not clear, countries that use anti stealth radar are not talking about the capabilities, e.g. what does "The superior stealth target tracking capabilities ensure optimal performance in demanding littoral environments." mean

https://www.thalesgroup.com/en/netherlands/news/new-fire-con...

or "Within this enormous range it detects a wide spectrum of targets: air breathing targets, stealth targets and ballistic missiles."

https://www.thalesgroup.com/de/smart-l-multi-mission-radar-0

or "It is also claimed to be highly capable of detecting stealth targets"

https://en.wikipedia.org/wiki/S1850M

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#26

Post by ChuckMcM »

Hmm, not your typical RADAR. This is basically using the RF emissions of the plane, and their detection at multiple RF detection stations with synchronized clocks, to determine the difference in arrival time. The radio emissions all travel at the same speed through the air, the difference in arrival time can be used with some simple trig to figure out where the RF emitter is. There are a number of Time Difference of Arrival or TDOA systems out there. It is why I expect aircraft stop using their radios when they are about to engage their targets.

That said, they are "easy" to jam in the sense that when you have two radio signals on the same frequency, they will interfere with direction finding. And there is a lot of noise in the RF spectrum out there, especially during thunderstorms.

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#27

Post by chmod775 »

rblatz wrote: post #23
Retric wrote: post #21

Earlier quoted context omitted.

Drones represent a huge range of different things. Assuming you mean something that’s a replacement for military aircraft. In order to have a useful X,000miles range and useful payload you need to build fairly large drones which means a large target. If their cheap that directly translates into low speeds making them a very easy target for anti air guns, or low cost anti aircraft missiles. If you want a large fast dr…

Why would you not deploy smaller drones via another platform? Small cheap disposable drones are a game changer. Drop them on a military base and have them seek and distort any human shaped targets, any sources of RF radiation, anything that looks like a vehicle or plane...

> Drop them on a military base

If you can get close enough to drop a bunch of slow drones, you can get close enough to just drop a bomb on the whole thing instead. Much more bang for your buck.

Let's also not forget that small drones might become 'banned' much like chemical weapons did, if they ever became viable.

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#28

Post by [deleted] »

kabouseng wrote: post #11
mikeyouse wrote: post #2

They do claim it works on all stealth planes including the F-35, but the B-2 is now 30 years old and was designed in the mid 1980s. Detecting it from 150 miles is impressive, but when they're equipped with 250 mile standoff air-to-surface missiles, ultimately not very useful. I'd be curious how much better the stealth is in the world of supercomputers and CFD for modern planes as well.

Well it's passive radar. So you don't have to outperform the stand-off range of the target, since you are invisible to the plane too.

[deleted]

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#29

Post by dmos62 »

HumblyTossed wrote: post #15
willvarfar wrote: post #12

Earlier quoted context omitted.

A goose flying at 600mph?

It could happen: https://en.wikipedia.org/wiki/Chicken_gun

In that vein: cold-war era chicken-heated nuclear bomb (for area denial) https://en.wikipedia.org/wiki/Blue_Peacock#Chicken_power

Re: Czech Passive Radar Detecting B-2 at 150 miles (2015)

#30

Post by whalesalad »

> Jamming hard and almost impossible to be destroyed by the anti-radiation missiles kill radar. Positioning and stick to the target in the air, on land and sea surface perfectly, providing enough parameters in real time.

This post is really quite garbage.

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