correct as-is OAP VRP VIP behavior

[leo2510]

As per the title: 
The configuration of the OA1/2 in the DEST page have an elevation value. This elevation shoul dbe a height and therefore AGL just like VRP/VIP and PUP. 
However, with the end of april 2022 update, the OA1/2 elevation is the altitude or ASL. 

Regards

Leo

[Shrike88]

+1 Replicated Last night on the PG, crosschecked with souce docs

[sjk132]

1. ELEV for OAP is the altitude delta to the steerpoint, ELEV for VRP, VIP appears to be MSL.  (so if we want to create a OAP and VRP at same height of our steerpoint, for OAP we need to put 0 for ELEV, for VRP we need to enter the MSL of the steerpoint)

2. When OAP and VRP have same BRG and RNG, the two point should have identical location, VRP, PUP, VIP appears to be off be a couple degrees. (can be seen in the trk file, using FCR we can observe VRP is not overlapping with OAP with same BRG and RNG)

3. After entering an OAP using DED DEST, after 3-4 min the BRG will drift by 0.1 degree, the longer the flight the more OAP's BRG will drift. (Can be seen in trk file toward the end)

4. CZ on FCR/TGP will reset OA1,OA2 to 0 BRG , 0 RNG. (in trk file, easily replicable)

 

These are some of the behavior I have observed when testing oap, vrp. I am unsure if they are the indented to be that way. Any clarification will be apricated. 

trk: https://drive.google.com/file/d/1bB0MPcRmM_F74vAbZHnYMNRg0QuiAg-x/view?usp=sharing

[Frederf]

All IP/RP/OAP ELEV are absolute elevations. All bearings for IP/RP/OAP are true bearings. Since IP/RP/OAPs are relatively displacements from a steerpoint their relative position must not change by INS drift. Any drift of steerpoint will cause both to drift by the same amount (discounting any tilt effects). CZ removes the slews in the bucket that you're currently in. IP/RP/OAP displacements are not cursor slews and must not be affected by CZ.

[NineLine]

Good post @Frederf

Based on feed back from the team this is correct as is. Thanks.

[leo2510]

I don't understand why you need a track replay ?
 

The Elevation in the AO page is clearly in ASL, its not a bug it's in the code or smth... 

VIP/VRP are in AGL and the AO points should also be in AGL

Furthermore, the AO are in TrueNorth it seems, it should be in MagNorth

Leo

Edited May 29, 2022 by leo2510

[sjk132]

  Track file in this post. I have asked if they should all be msl, still confused.

[Frederf]

If your TGT is elevation 1911' ASL and your OAP is elevation 1850' ASL one should enter those values directly into the system. Currently doing this in DCS will cause the OAP to appear at 1911+1850=3761'. I do not believe this is correct. If the designers wanted these values to be additive they wouldn't have labeled the OAP vertical position value "ELEV". They would have called it "delta ELEV" or "delta alt" or similar.

[SickSidewinder9]

Are VRP/VIP only visible in AG mode?  Was trying to use one of them to set up reference points for landing and didn't see anything on the HUD.

Is that correct behavior?

Edited June 8, 2022 by SickSidewinder9

[Shrike88]

Worked last week with a older viper driver.  He explained to me (who always used a pop up delivery planner for OAP).  When he was in Waypoint Dest offsets for Target points were either for DMPI or placed over known objects or terrain features with high radar return.  This was to adjust the INS Drift when running into a target.   Place OA1 over a large structure or hangar or bridge, cross reference with the briefing position and images, then he was able before run in to adjust Drift from the AG radar as it was a known offset and OA1 and Target point would both correct.  

As it was explained to me.   Hope this helps also when this feature is added to correct drift.