[INVESTIGATING] A-A Radar doesnt horizon stabilise

[Pikey]

Steps to reproduce:

 

1. Lock up a target wings level

 

2. Roll 90 degrees either direction and pull until you "think" the target is on a gimbal

 

3. Observe the locked contact not travelling in Azimuth and te radar elevation moving down.

 

 

 

Expected: the target moves towards the radar scope gimbal at the sides

 

Actual: The target remains centered

 

 

4. Roll out wings level

5. Observe the target move in Azimuth suddenly and elevation on antenna snap up.

 

 

 

Expected: the target shouldnt suddenly move in azimuth on the radar scope

Actual: as you roll, the target rapidly shoots towards the gimbal because the radar is rotating with it.

 

 

CONCLUSION

 

This shows 100% that the radar on the JF-17 does not ground stabilise. I dont believe any modern aircraft radar works like that as it makes elevation act as Azimuth and azimuth act as elevation and the target can't be held when violently manouvering on a gimbal.

 

 

 

IMPACT:

 

I've seen this before (m2k on release) and it's really bad for air combat because you cannot crank to the gimbals and thus can't perform essential combat. Worse, at the gimbals, if you roll, you will break lock.

 

EDIT:Easier explanation. Roll constantly with a radar track and HSD RWR track off to one side and notice how their bearings change in the avionics. Ie, a track will swing around different bearings when it's not actually changing its bearing to you at all. In the code, because the radar isn't ground stabilised, it thinks that when it's on it's side, the track is below/above it and at 0 bearing! When in actual fact the item is bearing 045 right or left. I can make a video identical to my M2000 video demonstrating this, let me know if the dev can't understand this since it's a visual thing.

Edited December 5, 2019 by Pikey

[uboats]

thanks for all the details

we will try to reproduce then fix it

[Evovcui]

I’m confused about this, too. Even the gimbal is not horizon stablized, the rdr page and hsd

should be able to give the right target bearing via the attitude of plane. Hope to see DIS fix it.

[Pikey]

Yes there's other avionics demonstrating this behaviour too - The HSD demonstrates the same behaviour in rolls, swinging around during a roll but no heading change will move the bearing to the item. Pretty sure the MAWS is too but I didnt check as I was busy at the time ;) CEDIT: Come to think of it, im not sure if a modern MAWS or RWR will ground stabilise. HB modelled lack of it in the Tomcat - it's a simpler system and only points directly at the radar source. Whilst I do know that radars ground stabilise, I do NOT know if a RWR does because I have no references. If I was designing an RWR though, I certainly would.

 

I’m confused about this, too. Even the gimbal is not horizon stablized, the rdr page and hsd

should be able to give the right target bearing via the attitude of plane. Hope to see DIS fix it.

Edited December 5, 2019 by Pikey

[L0op8ack]

Comfirmed.

 

 

Radar/datalink contacts polar is computed agaist plane matrix,

should be sensor matrix.

 

 

Will fix.