Slewing to datalink targets

[Frederf]

It has also something to do with barometric altimeter adjustment. Angle from Ka-50 to get depends on two things: understood vertical position of target, understood vertical position of helicopter.

 

Ka-50 uses barometric altimeter (Doppler? INU? combination?) to determine its vertical position. This can be seen by uncaging at TGT or DL point (no laser, no track) and then adjusting altimeter Kollsman knob. For settings below or above a certain value the LOS will raise above a minimum elevation angle. Because of this a non-standard pressure and temperature has a dramatic effect on vertical alignment.

 

From limited tests it appears that system doesn't save elevation at all but always assumes co-altitude horizontal plane and an elevation angle. ABRIS shows assumed range by passive calculation. When baro alt shows actual vertical displacement.

 

For example if Ka-50 and target are both at terrain which is 1200m elevation and Ka-50 is +700m then passive ranging will only be correct if Ka-50 altimeter is reading 700m (not 1900m). Naturally this is a different setting based on pressure and temperature, 20 to 10C for example needing 650 or 655mm setting respectively.

 

Vertical aiming seems only reasonable if altimeter is constantly adjusted so it always reads height above intended target.

Ka50TGTDLelevBaro.trk

[Taz1004]

1 hour ago, Frederf said:

It has also something to do with barometric altimeter adjustment. Angle from Ka-50 to get depends on two things: understood vertical position of target, understood vertical position of helicopter.

 

Ka-50 uses barometric altimeter (Doppler? INU? combination?) to determine its vertical position. This can be seen by uncaging at TGT or DL point (no laser, no track) and then adjusting altimeter Kollsman knob. For settings below or above a certain value the LOS will raise above a minimum elevation angle. Because of this a non-standard pressure and temperature has a dramatic effect on vertical alignment.

 

From limited tests it appears that system doesn't save elevation at all but always assumes co-altitude horizontal plane and an elevation angle. ABRIS shows assumed range by passive calculation. When baro alt shows actual vertical displacement.

 

For example if Ka-50 and target are both at terrain which is 1200m elevation and Ka-50 is +700m then passive ranging will only be correct if Ka-50 altimeter is reading 700m (not 1900m). Naturally this is a different setting based on pressure and temperature, 20 to 10C for example needing 650 or 655mm setting respectively.

 

Vertical aiming seems only reasonable if altimeter is constantly adjusted so it always reads height above intended target.

Ka50TGTDLelevBaro.trk 347.46 kB · 1 download

 

Thing is the datalink target points I save contains altitude info.  But not the one from the wingman.  Or the target point made in ME.  I have not tried target point saved from ABRIS.

And like I've said, sometimes it's above, and sometimes it's below.  Targets in Shooting Range Caucasus I tested were at 584 feet.  So it was slewing to altitude below that.

[Sh4rk]

Is your helicopter at the same altitude the wingman was when it sent you the datalink target?

 

DL supposedly saves targets based on your own aircraft's altitude (bearing, range) when you acquire them. It might be just slewing your Shkval to the expected parameters as if you were at the same position or vertical plane your wingman was when it datalinked them to you. 

 

Next thing would be to make sure both you and wingmen have the same QFE settings.

 

Or we should all get into a server to sort out these kinds of issues

[Taz1004]

38 minutes ago, Sh4rk said:

Is your helicopter at the same altitude the wingman was when it sent you the datalink target?

 

DL supposedly saves targets based on your own aircraft's altitude (bearing, range) when you acquire them. It might be just slewing your Shkval to the expected parameters as if you were at the same position or vertical plane your wingman was when it datalinked them to you. 

 

Next thing would be to make sure both you and wingmen have the same QFE settings.

 

Or we should all get into a server to sort out these kinds of issues

 

Well, that'd be absurd even if that was the cause.  How am I supposed to match my altitude to my wingman everytime?  But it's not related to my altitude or the wingman's altitude.  Offset is always constant based on the map.

 

Are you saying this is working for you?

[Sh4rk]

It used to, it's been a while I don't try it (in 2.5.6) since I can't find proper Ka50 wingmen on servers, let alone wingmen that know how to use the Datalink

 

It might be a bug that's been introduced in 2.5.6 / Black Shark 2.5, or in the new maps (since it worked on Caucasus). I'll test when I have the chance.

 

 

 

[Taz1004]

15 minutes ago, Sh4rk said:

It used to, it's been a while I don't try it (in 2.5.6) since I can't find proper Ka50 wingmen on servers, let alone wingmen that know how to use the Datalink

 

It might be a bug that's been introduced in 2.5.6 / Black Shark 2.5, or in the new maps (since it worked on Caucasus). I'll test when I have the chance.

 

 

 

 

This thread is 5 year old.  And there are YouTube videos dating back to 2013 showing same issue.

Edited February 5, 2021 by Taz1004

[Sh4rk]

I'm sure I used the datalink with wingmen (human) in MP before. Didn't have the issue as far as I can remember.

 

Might be a different thing with AI wingmen (missing altitude or QFE information) or maps (some other reasoning).

But ABRIS for example did have some issues related to altitude, from 2.5 onwards, like water showing as ground. DCS didn't use to have depth in the oceans, which was tied in some way to how altitude is handled. They might have broken some function?