4 ms·

I thought most OTH can see stealth planes because they usually aren’t optimised for being scanned from the top, but rather more front, back and bottom face scan

by _kbh_ 5y ago

I thought most OTH can see stealth planes because they usually aren’t optimised for being scanned from the top, but rather more front, back and bottom face scanning. I don’t know much about stealth though so I could be completely wrong.

WJW 5y ago
There are many variables involved in radar target detection and usually "stealth" planes only have the possibility to optimize for a few of them. As a simple example, radar absorbing paints usually only work well in a few frequency bands so using a radar outside that band gives a much higher chance of detection. Using "blocky" designs reduces the chance of detection from one angle (typically the front, since that is where the target is) but at the cost of higher detectability from another angle. And finally you will almost always have problems with infrared visibility from some angles, for a jet airplane it is almost impossible to hide the exhaust plume when looking from the rear of the aircraft. In any case, you are right that OTH skywave radars like the Nostradamus usually have a pretty good chance to detect stealthy planes. However due to the frequency bands involved such detections are typically more of the "there is something in this cubic kilometre" type and not of fire-control quality. You need much more accurate systems to actually guide a missile. Still, it is pretty cool. There are also "passive" systems which use the reflections of waves from normal civilian radio stations and a phenomenal amount of signal processing to determine the position of thousands of targets simultaneously, although I'm not aware of any in active service yet. Like fusion power, this type of "multistatic" radar seems to be perpetually 30 years away from practical use. Source: Used to be a weapons engineer for the Dutch Navy, at one point specializing in advanced radar systems.

by _kbh_ 5y ago

WJW 5y ago

There are many variables involved in radar target detection and usually "stealth" planes only have the possibility to optimize for a few of them. As a simple example, radar absorbing paints usually only work well in a few frequency bands so using a radar outside that band gives a much higher chance of detection. Using "blocky" designs reduces the chance of detection from one angle (typically the front, since that is where the target is) but at the cost of higher detectability from another angle. And finally you will almost always have problems with infrared visibility from some angles, for a jet airplane it is almost impossible to hide the exhaust plume when looking from the rear of the aircraft. In any case, you are right that OTH skywave radars like the Nostradamus usually have a pretty good chance to detect stealthy planes. However due to the frequency bands involved such detections are typically more of the "there is something in this cubic kilometre" type and not of fire-control quality. You need much more accurate systems to actually guide a missile. Still, it is pretty cool. There are also "passive" systems which use the reflections of waves from normal civilian radio stations and a phenomenal amount of signal processing to determine the position of thousands of targets simultaneously, although I'm not aware of any in active service yet. Like fusion power, this type of "multistatic" radar seems to be perpetually 30 years away from practical use. Source: Used to be a weapons engineer for the Dutch Navy, at one point specializing in advanced radar systems.