investigating EXP3 radar sweep speed and updates are unstable.

[Rissala]

Hornet has the following issues with the EXP3 SAR map scanning and the update process when designating.

Issues:

- When using EXP3, the scan speed (angular vel.) is heavily dependent on roll for some reason.
- It is possible to completely halt or slow the scan significantly when rolling a few degrees to some direction.

Rolling should not affect the scan speed since the radar is gimballed and always facing the intended scan area. (ground stabilised)

- When designating a new spot with the EXP3, the system for some reason still attempts to complete the previous frame, which when combined with the slowdown issue above results in extremely slow designations and general use.

This should also not happen as described by @IvanK, who seems to have some IRL experience on this system:


Both issues are demonstrated in the track attached.

Could be related to the previous issues with movement here:
 

 

Hornet A-G radar scan speed and update.trk

Edited December 16, 2021 by Rissala

[BIGNEWY]

Please for future reports only post one issue per report. I will speak to the team, but do you have any evidence to back up the claims. 

thanks
 

[MARLAN_]

The part where rolling affects the radar seems to affect the A/A Radar as well.

It would likely be quite difficult to find specific evidence that says the radar doesn't get degraded by rolling.

The F/A-18C pilot I know has said the radar should not be affected by rolling, if that helps at all. It's particularly silly for A/A, during a re-attack, or even a CRANK, you can lose radar SA with the DCS modeling causing roll to degrade the radar.

(Not entirely sure if it's specifically roll, I've just noticed loss of radar SA during cranks/re-attacks, it may have something to do with G, I just tested now and was able to reproduce it, but I am unsure what exactly is causing it)

Edited December 15, 2021 by MARLAN_

[Northstar98]

The RADAR is horizon stabilised in all modes but ACM (apart from WACQ), and the radome has a circular cross-section, what evidence is there to suggest that roll would have any effect on it?

Edited December 16, 2021 by Northstar98

[=4c=Nikola]

11 minutes ago, Northstar98 said:

The RADAR is horizon stabilised in all modes but ACM (apart from WACQ), and the radome has a circular cross-section, what evidence is there to suggest that roll would have any effect on it?

 

What are limitations of stabilization system?

[Northstar98]

14 minutes ago, =4c=Nikola said:

What are limitations of stabilization system?

I don't know the rates but fairly sure it manages full 360°

Though not sure what that has to do with the OP's issues.

Edited December 16, 2021 by Northstar98

[Rissala]

13 hours ago, BIGNEWY said:

Please for future reports only post one issue per report. I will speak to the team, but do you have any evidence to back up the claims. 

thanks
 

I did post some evidence for the second issue.
This evidence is from @IvanK and from this thread page 2. He seems to have some IRL experience on this sensor. In addition to his statement, it does not make sense to still attempt to scan the old frame after a designation. It should begin scanning centered on the new frame to save time and give the pilot a more usable system. I can't see the logic behind the current designation where the radar is still scanning the old frame.

For the first issue, it makes no sense that the sweep speed is affected by some modest changes in roll since the radar is gimballed and always faces the scan area anyways. This issue does not happen with the F-16. (should not happen with Hornet either)

As a logical example, you can still scan for aerial targets even when you are inverted, as long as your enemies are within gimbal limits. So I'd like to see the evidence (or just hear from you) that says radar scan speed is affected by roll for some reason.

Still, thanks BN for notifying the team

12 hours ago, MARLAN_ said:

The part where rolling affects the radar seems to affect the A/A Radar as well.

It would likely be quite difficult to find specific evidence that says the radar doesn't get degraded by rolling.

The F/A-18C pilot I know has said the radar should not be affected by rolling, if that helps at all. It's particularly silly for A/A, during a re-attack, or even a CRANK, you can lose radar SA with the DCS modeling causing roll to degrade the radar.

(Not entirely sure if it's specifically roll, I've just noticed loss of radar SA during cranks/re-attacks, it may have something to do with G, I just tested now and was able to reproduce it, but I am unsure what exactly is causing it)

 

You are kinda on the right track but if you use the EL/AZ page often you will see the issue. Sometimes when rolling many times over at a fast pace, the radar is just not fast enough to follow the target. This as far as I know is intended behaviour. I have not seen any reduction in scan speed when rolling or moving violently.

[Rissala]

11 hours ago, Northstar98 said:

I don't know the rates but fairly sure it manages full 360°

Though not sure what that has to do with the OP's issues.

 

Yeah the radar is on a gimbal, so I don't see why rolling slightly should change the scan speed on EXP3. This is why it is related to the issue.

Edit: The reason why I say "slightly" (10-15 degrees) is because violent rolling can definetly halt the scan.

Edited December 16, 2021 by Rissala

[MARLAN_]

1 hour ago, Rissala said:

I did post some evidence for the second issue.
This evidence is from @IvanK and from this thread page 2. He seems to have some IRL experience on this sensor. In addition to his statement, it does not make sense to still attempt to scan the old frame after a designation. It should begin scanning centered on the new frame to save time and give the pilot a more usable system. I can't see the logic behind the current designation where the radar is still scanning the old frame.

For the first issue, it makes no sense that the sweep speed is affected by some modest changes in roll since the radar is gimballed and always faces the scan area anyways. This issue does not happen with the F-16. (should not happen with Hornet either)

As a logical example, you can still scan for aerial targets even when you are inverted, as long as your enemies are within gimbal limits. So I'd like to see the evidence (or just hear from you) that says radar scan speed is affected by roll for some reason.

Still, thanks BN for notifying the team

You are kinda on the right track but if you use the EL/AZ page often you will see the issue. Sometimes when rolling many times over at a fast pace, the radar is just not fast enough to follow the target. This as far as I know is intended behaviour. I have not seen any reduction in scan speed when rolling or moving violently.

The radar in DCS moves ~30 degrees per second (you can time this) which should mean any turn you do wouldn't affect the radar, it seems to be lagging behind more than it should be as far as I can tell.

Roll itself though, should have no effect on the radar.

[Rissala]

31 minutes ago, MARLAN_ said:

The radar in DCS moves ~30 degrees per second (you can time this) which should mean any turn you do wouldn't affect the radar, it seems to be lagging behind more than it should be as far as I can tell.

Roll itself though, should have no effect on the radar.

Please post your own topic about this issue. Thanks.

[Rissala]

Previous topic about the designation logic. Still under investigation.
 

 

Edited December 16, 2021 by Rissala

[MARLAN_]

13 minutes ago, Rissala said:

Please post your own topic about this issue. Thanks.

I brought it up because it sounds like they are issues possibly caused by the same problem 

[Rissala]

20 minutes ago, MARLAN_ said:

I brought it up because it sounds like they are issues possibly caused by the same problem 

You can still post your own topic and then link it to the one related like this. Keeps things organized.