Or the materials and components behind radar "transparent" material like composites. Geometric models are indeed not enough to determine true RCS.
H-20 bomber (with H-X, JH-XX)
- Thread starter Deino
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Or the materials and components behind radar "transparent" material like composites. Geometric models are indeed not enough to determine true RCS.
Reconnaissance Satellites with radar able to spot aircraft is almost certainly possible and almost certainly exist. As early as the 1970s, the Soviets launched a series of radar ocean reconnaissance satellites designed to detect US surface fleet and providing real-time targeting and mid course guidance updates for anti-ship cruise missiles launched from beyond the horizon. With 50 additional years of progress on electronics and signal processing, it is difficult to image satellites with radar that can detect most aircraft from orbit would still be beyond technical state of the art.
In the late 1990s the USAF is known to have launched a series of classified satellites that unfurled enormous downward facing antennas once in orbit. These were almost certainly high sensitivity radar reconnaissance satellites.
Geometry is the most important element of RCS and "true" RCS does not play a role.
Look at this graph and pay attention to the performance of high power and large aperture Irbis-E radar and the low-power and small aperture missile seekers. The first is doing all the combat management, the latter only affects whether the missile hits.
The scale is logarithmic so it distorts data heavily in the upper bounds but the seekers are represented fairly naturally. It doesn't matter that much. Either the IR seeker or constant uplinks (hence the role of ECCM) will address the issue.
The greatest reduction in detection range occurs between RCS=10m2 and RCS=0.5m2 all of which can be achieved through geometry alone. Below 0.5m2 we enter into an area where IRST outperforms radar in most atmospheric conditions, but most importantly it is the standard range of modern medium-range air-to-air missile which makes it the contemporary equivalent of missile dogfights of the recent past.
Whether your stealth plane has RCS of 0.01 or 0.001 is irrelevant for all purposes other than conservation and maintenance. If you have 0.001 then any loss resulting from use will not increase it beyond 0.1 range determined largely by geometry and selective applications of other techniques in crucial spots on the airframe.
The geometry and RAM matter in terms of reducing scatter from other angles - most importantly high altitude radar. RAM will most likely also try to reduce other wavelenghts because with bombers not being targeted is not as important as not being discovered.
Anyway, just my three cents.
Look at this graph and pay attention to the performance of high power and large aperture Irbis-E radar and the low-power and small aperture missile seekers. The first is doing all the combat management, the latter only affects whether the missile hits.
The scale is logarithmic so it distorts data heavily in the upper bounds but the seekers are represented fairly naturally. It doesn't matter that much. Either the IR seeker or constant uplinks (hence the role of ECCM) will address the issue.
The greatest reduction in detection range occurs between RCS=10m2 and RCS=0.5m2 all of which can be achieved through geometry alone. Below 0.5m2 we enter into an area where IRST outperforms radar in most atmospheric conditions, but most importantly it is the standard range of modern medium-range air-to-air missile which makes it the contemporary equivalent of missile dogfights of the recent past.
Whether your stealth plane has RCS of 0.01 or 0.001 is irrelevant for all purposes other than conservation and maintenance. If you have 0.001 then any loss resulting from use will not increase it beyond 0.1 range determined largely by geometry and selective applications of other techniques in crucial spots on the airframe.
The geometry and RAM matter in terms of reducing scatter from other angles - most importantly high altitude radar. RAM will most likely also try to reduce other wavelenghts because with bombers not being targeted is not as important as not being discovered.
Anyway, just my three cents.
From publicly available information on RAM, shaping is what gets a 25 m^2 fighter down to the 0.01m^2 fighter range, but consider that the F-35 is 0.0001m^2. Especially with metamaterials stealth, RAM is increasingly important, not just for hot spots, but also for getting the aircraft to its final 10-30 dB of stealth.
Geometry is but one aspect. RAM application, location of use, how control surfaces move and reposition, joints, seals, detailing etc are all part of true RCS. By true RCS, I'm referring to an aircraft actual RCS in real life. Something photos and even perfectly developed geometric models cannot ascertain. Perfect geometric models may reveal far greater depth of detail than basic geometric models developed from photos and "close enough" examination of a shape but perfect geometric models do not tell the examiner what lies beneath the skin, where RAM applications are located (assumed but this is on principle for models based on visual material only), and the specific applications for seals, paint, and RAM formula.
You can’t get an accurate RCS estimate from a model, but you *can* figure out where the major spikes and hotspots are, and that goes a very long way in assisting detection.
But SAR Satellites technically shouldn't be able to do real time detection and tracking. It is not possible unless you know what to look for where to look for and ofcourse have real time data processing, detection and such. Especially for stealth aircraft, it is near impossible.
SAR maybe useful against Ships as it's against in a relatively uniform background, has relatively slow speeds (max 60 mph..) etc.
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by78
General
Where did you get F-35 RCS figure from? Are you making stuff up again?
He is taking the approximate figures for just the frontal RCS using the information from the Lockheed promotion that touted the frontal RCS of F-22 as 0.0001m2.
With DSI and metamaterials ( which F-35 indeed does have) it should be lower. But I've noticed that many pro-US individuals trying to prop up F-22 as having superiority over F-35 or any other aircraft in stealth. It isn't one based on facts or information though - just emotional. They'd want to have their primary heavy air superiority fighter not be shown lacking even though it uses technology from 1980s to 1990s. Understandable.