Effect of pitch angle on radar detection altitude
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I guess another thing that would come into play is how fast the RADAR can actually move. (not a factor with AESA, perhaps?)
At a fixed pitch angle of 30°, I suppose it can still remain stabilized on the horizon, but if you fly level and pull a lot of G to that 30°, can the radar keep up or will there be a delay? If so, how long will that delay be?
Good point as well. But you can see the bar scan in the radar screen, it scans 60° in 2s, so I think the delay would be not that significant anyway. Obviously, this is assuming the antenna moves as fast in pitch and in yaw.
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imo, the radar gamble can handle a lot of pitch. Look at the AG operations. 45* lofting at targets less than 5nm. Or is that a SPI trick?
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As far as I know, stabilized in pitch +/-60° … Not in roll.
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As far as I know, stabilized in pitch +/-60° … Not in roll.
So as soon as you bank a bit, you lose a lot of coverage…. if it is indeed the case, that could be interesting to implement.
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So as soon as you bank a bit, you lose a lot of coverage….
It depends on your alt, bank angle, where you are looking (distance) and antenna elevation ….
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It depends on your alt, bank angle, where you are looking (distance) and antenna elevation ….
Absolutely ! But still, the forward “rectangle” that you are scanning will be rotated with your bank.
So as soon as you bank a bit much, your coverage is more vertical than horizontal anyway.
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An Inertial Measurement Unit is mounted to the base of the antenna to provide automatic boresight correction capability. There are four coordinate systems used by the radar to allow the best functionality based on the radar mode, providing stability vs the horizon (pitch) and roll within gimbals among others.
BTW, the radar would anyway benefit from a complete update…
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An Inertial Measurement Unit is mounted to the base of the antenna to provide automatic boresight correction capability. There are four coordinate systems used by the radar to allow the best functionality based on the radar mode, providing stability vs the horizon (pitch) and roll within gimbals among others.
BTW, the radar would anyway benefit from a complete update…
Bot how can make such a compenstaion which is impossible?
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As far as I know, stabilized in pitch +/-60° … Not in roll.
Ok this one had be digging through the books as it wasn’t a problem that I ever addressed. It is stabilized in pitch and in roll. You can momentarily lose roll stabilization in FCR due to the high roll rate of the F-16.
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An Inertial Measurement Unit is mounted to the base of the antenna to provide automatic boresight correction capability. There are four coordinate systems used by the radar to allow the best functionality based on the radar mode, providing stability vs the horizon (pitch) and roll within gimbals among others.
This is not correct. The FCR receives Pitch, Roll, and Magnetic heading from either the INS directly or indirectly through the FCC/GAC/MMC for stabilization. Those signals go from the INS/MMC to the PSP in the FCR system. The PSP directs the movement of the antenna for stabilization.
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Bot how can make such a compenstaion which is impossible?
Of course its possible. You adjust the antenna pattern to take into account the pitch and roll, thats all.
Ex :
-AC is banking 25° clockwise-> you rotate the bars 25° counterclockwise so that they remain horizontals.
-AC is pitching 15° up -> you move the antenna elevation 15° down so that you scan the same volume.
Etc.Antenna moves quite fast, so except in limit roll, it can catch up quite fast.
Pitch and roll attitude is given by the INS, probably.
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Of course its possible. You adjust the antenna pattern to take into account the pitch and roll, thats all.
Ex :
-AC is banking 25° clockwise-> you rotate the bars 25° counterclockwise so that they remain horizontals.
-AC is pitching 15° up -> you move the antenna elevation 15° down so that you scan the same volume.
Etc.Antenna moves quite fast, so except in limit roll, it can catch up quite fast.
Pitch and roll attitude is given by the INS, probably.
Correct. The FCR takes this information (pitch, roll, magnetic heading) from the INS and uses it to stabilize in pitch and in roll. Obviously if the pilot goes outside of the physical gimbal limits of the FCR the it will have to do something else. I’m not sure what it does in that situation as the CDCs didn’t cover that situation.
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Bot how can make such a compenstaion which is impossible?
The B-scope is a graphical representation of ranges and vector. Altitude is computed by slant angle and range. Velocity and heading is computed by a historical track file. FCR know its INS attitude.
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This is not correct.
Well, it was pasted as-is…
The FCR receives Pitch, Roll, and Magnetic heading from either the INS directly or indirectly through the FCC/GAC/MMC for stabilization. Those signals go from the INS/MMC to the PSP in the FCR system. The PSP directs the movement of the antenna for stabilization.
The FCR takes this information (pitch, roll, magnetic heading) from the INS and uses it to stabilize in pitch and in roll.
Pitch and roll attitude is given by the INS, probably.
So according to your assumption, if the bird looses INS, = no radar proper operation due to drifts… Or better, if INS = off, and GPS = jammed or EGI lost alignment, then again no radar proper tracking…
The antenna movement vs aircraft reactions is controlled from its dedicated Inertial Measurement Unit. The FCR through MMC and INS provide target data placement in the 3D space and FCR MFD.
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If the GPS fails and the INS drift it porks Bullseye and the HSD bug from other flight member’s d-link. It still does BRA just like the days before GPS. It has happen to me a few times in F4AF MP.
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Of course its possible. You adjust the antenna pattern to take into account the pitch and roll, thats all.
Ex :
-AC is banking 25° clockwise-> you rotate the bars 25° counterclockwise so that they remain horizontals.
-AC is pitching 15° up -> you move the antenna elevation 15° down so that you scan the same volume.
Etc.Antenna moves quite fast, so except in limit roll, it can catch up quite fast.
Pitch and roll attitude is given by the INS, probably.
The radar antenna has a maximum gimbal area. What happens if you are flying higher and use in level flight in a -30 deg elevation then you do a barrel roll to evade a SAM? It can happen that to keep the necessary scan zone the radar will go outside the gimbal limit… This does not modeled in game. What about the realitiy? Regardless of turn rate the radar is capable to change always and so quickly the scan pattern? Currently you can set up such an elevation angle which literally means that you can scan the airpace below your AC…
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The radar antenna has a maximum gimbal area. What happens if you are flying higher and use in level flight in a -30 deg elevation then you do a barrel roll to evade a SAM? It can happen that to keep the necessary scan zone the radar will go outside the gimbal limit… This does not modeled in game. What about the realitiy? Regardless of turn rate the radar is capable to change always and so quickly the scan pattern?
Gimbal limit is important in pitch. As the antenna has a +60/-60 field, you really need to get your nose up or down to lose coverage. Gimbal in yaw is not really relevant, the radar does not scan in a specified fixed bearing but always compared to the AC nose.
The antenna moves pretty fast anyway : a bar scan takes 2s to scan 120°. So I think it can keep up with whatever pitch rate you have.
Roll rate is something else though. As you need to keep the bar horizontals, and the F-16 roll rate is quite big, you can lose the ability to do a proper scan. Maybe have troubles maintaining track too.
But you are not really supposed to do quick rolls in succession anyway, its neither useful nor safe for departures prevention. -
But you are not really supposed to do quick rolls in succession anyway, its neither useful nor safe for departures prevention.
While you are in a BVR fight in head to head case with SARH missiles for keep the track and STT lock for you missile is require to lock even you do defensive turn. Not only F-16C + AMRAAM exist in the world. What I heard the cassegrain antenna of Russain jets simply makes impossible the F-pole because its bank angle and other limitations. Therfore I guess are limitations for other radar antenna types.
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While you are in a BVR fight in head to head case with SARH missiles for keep the track and STT lock for you missile is require to lock even you do defensive turn. Not only F-16C + AMRAAM exist in the world. What I heard the cassegrain antenna of Russain jets simply makes impossible the F-pole because its bank angle and other limitations. Therfore I guess are limitations for other radar antenna types.
I agree, but some actual doc would be nice before changing anything.
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…you are not really supposed to do quick rolls in succession anyway, its neither useful nor safe for departures prevention.
LOL…!
I’d like to survive this encounter, but - I really shouldn’t do quick rolls in succession, so… BANG