IvanK

"Nudge" applied

HSI AC DATA has a page that shows Wind direction and speed ... had a look it just says wind direction 045 with no velocity in this scenario.IRL it should show INS derived wind speed and direction. EDIT: Just put 40Kts of wind in at all levels. Velocity doesn't show up on the AC Data page just reads 0. So yet to be implemented I think. EDIT2: And of course with real wind present in AG mode the VV,Pitch ladder and all other linked symbology drifts down wind in the HUD.

As I understand it IRL when the RADALT warning goes off the top option window of the UFC shows :RALT, you can silence he warning by de-colonising the RALT option, when you do that the RALT legend extinguishes. So just a quick way to kill the warning.

A few more numbers that give magnitude to this CCIP/AUTO POS INS issue. Looking at known dimensions of FA18 HUD symbolgy, and extrapolating where the CCIP cross would be based on the reflected cue. Reveals it to be 170mills displaced from the VV. Now Looking at MK82 LD Ballistic tables for a 10deg dive 560KTAS at 2400ft Altitude gives a 1.79 Mill/Kt crosswind correction factor. So 170mills is basically equivalent to a 95Kt cross wind component. ..... and we know actual wind is zero.

Sitting on the ground same location POS INS 1985 Take a Mark point. Select MK point and selecting steering to Mark point. range obviously 0.0nm. Do nothing 1 hour later Markpoint drifts to 039M/for 1.3nm = INS drift

White AMPCD symbols in E/F/G ... screen grab from Growler video Vid: https://fb.watch/7cLSP-YBYc/

More testing. Again 1985 44mins POS INS Designated then flew for 44 mins. INS Drift measured as 008T/117m . Same Story CCIP and ASL leaning over as before. Re designated same deal ASL pops up left and CCIP and DIL way out to right. So then using CCIP flew around to establish where the CCIP cross and DIL were vertical under the VV Heading 220 DIL and CCIP + Vertical Heading 310 DIL and CCIP + Leaning way out to right Heading 040 DIL and CCIP + Vertical Heading 180 DIL and CCIP + Leaning way out to Left So deduced that the "Pseudo Wind " error lies on the 220/040 bearing Dropped on Heading 040 Bomb impacts well short >500m short Dropped on Heading 220 Bomb impacts Well over the top >500m Long (A further note on heading 220 I could not ever achieve a CCIP solution as CCIP + was off the bottom of the HUD regardless of Dive angle and IAS. AUTO solution was possible) So to me if this is a "Pseudo wind" issue then the Pseudo wind is blowing or its affect is coming From 220M

How does an incorrect altitude affect the horizontal displacement of the Dil and CCIP + ?

I tried the switch didnt do anything for me, no change. Svend. Being ok on two headings with Long Short errors and displace on other headings would fit with the pseudo wind therory. When Directly into wind DIL would be vertical, When going crosswind obviously leaning downwind.

INS updates should not affect the lateral position of the CCIP. CCIP is not dependent on positional data. In other words it doesn't give a dam where in the world you are. As a side note the update process is not yet functional in DCS imo.... and when it is in the POSINS domain then brings in the subject of your Accept/Reject criteria. As to DTED and its relevance in CCIP. I think this a red herring .... again the issue we are seeing is the lateral displacement of the CCIP DIL line. In Auto we get a similar effect with the ASL even after a point blank designation .... again with an AGR range sample. The system is currently porked without POSAINS. Gripes I think your selection of POS/ADC and back to POS/INS and getting the DIL line back to vertical is a good finding and narrows down the cause of this bug. I don't see its relevance IRL but in the DCS internal calcs it seems super relevant to me. Thinking this further (brain hurting). We know the DIL/ASL error gets bigger with with time. We have seen that if the erroneous CCIP DIL is displaced to the RIGHT then we designate the erroneous ASL is displaced to the LEFT even in zero wind. This would make sense if the DCS MC2 thought there was a significant wind from the LEFT. This would mean the CCIP + would be deflected downwind and the ASL steering reference would be displaced upwind(exactly what we are seeing) We also have seen the displacement is always Easterly for the CCIP + and westerly for the ASL. We know in the Sim the bombs still fall directly under the VV. We know we don't see this bug if using POSAINS with GPS input.... so in essence any INS drift is corrected for by the mixed INS/GPS solution, so in the SIM with POSAINS there is no need to model system drift. So ....... Is DCS using a pseudo internal wind to simulate INS drift in POSINS ?.... Perhaps the switch from POSINS to POSADC and back to POSINS resets some internal variable (zeroing the pseudo wind) to start the pseudo INS wind drift again ?? So you start from zero and everything looks ok..... keep flying and the issue accrues from that switch over time as T=0. Off to test some more.

And whatever it is its screwing with AUTO as well.

Australian,Canadian,Spanish,Swiss,Kuwaiti, Blue Angles and perhaps a few others have VOR and ILS installed replacing the USN ILS system ... its a customer option. On those Hornets equipped VOR or ILS is selected using the AIDS push button on the HI top left button. Once selected other options of VOR or ILS are presented. If you want VOR you box VOR if you want ILS you box ILS. International DME is automatically paired by selection of VOR or ILS frequency. Freq selection is done via the UFC. You press the same UFC ILS function button. The UFC then displays VOR and ILS in the 2 top option windows. Colonise the option you want then allows VOR or ILS freq (which are VHF) to be entered. System is capable of back course approaches as well. Steering for VOR is the same as for TACAN. ILS is almost the same as for the USN ILS system with the addition of marker beacon cueing that appears in the HUD as you pass each marker. ILS QDM is entered via the CSEL switch.... as is the desired radial for VOR course line steering. The USN old manual ILS tuning panel on the left console is still strangely present (though non functional) on those Hornets fitted with VOR/ILS. It would be a great "option" to have in DCS ... perhaps tied with the nationality you select in FMB. Its an Old image from the last century as evidenced by the map ... what the VOR,ILS and International DME steering options looked like in an RAAF FA18A. This was before the AIDS legend was next to the top left HI button.

A reference I have ... though referring to the HSI and UFC time entry says: "Zulu Time-Of-Day is displayed in the lower left corner of the HSI format followed by the legend "EI" (Engine Indicator). " ....

We are talking about "Old Hornet models" pre GPS Hornet, without DTED and using AGR. That is what DCS is simulating if you have a mission date before 28 March 1994 as I see it. In any case regardless of Slant range source the DIL shouldnt be displaced from the vertical nil wind and in balanced flight !

"....which actually fits the CCIP behavior" What do you mean by this statement ? exactly what behavior ?

POA/AINS and GPS comes available in the Sim for missions on or later than 28 March 1994

Agree with TDC slewing being to imprecise.

Overthinking this I I wondered if this was some error in Schuler loop modelling (if it is in DCS and if the DCS world is not flat). So repeated the experiment to be back on tgt after 84 mins flight time (schuler cycle time). Well All I got was huge errors in the same direction as before check out the CCIP (reflected cue) and DIL line now

Another test. Same mission 1985 no GPS POS INS no wind. Initially did a Point Blank HUD designation (flt time 2 mins), ASL appeared centered on the designation diamond as expected. Then flew for 30 odd mins. INS drift as in previous post much the same. So Undesignated. Came around and did another Point Blank (HUD) designation (33 mins flt time). ASL pops up displaced to the left.?? why given its a new designation and nil wind it should be through the designation diamond. ... Something is off and it relates to Flight time. Came around again and did a CCIP pass, DIL and CCIP was leaning out to the right (East again).

Another test this time using AUTO and looking at a Manual designation and what happens after 26 mins flying. Interestingly the ASL is displaced to the South. The top image is immediately after the HUD designation. The Designated point has drifted 041 for about 151m i.e easterly. Which for an un updated raw INS system is pretty good imo and works out about 300m per hour. However given this is Nil wind I would have expected the ASL to be running through the Designation diamond ?

Some more testing. Again DIL line always seems to be displaced to the east after 30 odd mins flying POS INS. AGR display indicates 0 Vel error. Again nil wind. Images depict CCIP and subsequent impact point (x). Interestingly Impact point lies directly under the VV adjacent the CCIP + position ... i.e. about were the CCIP + should be if it and the DIL weren't leaning over to the East.

In my tests I have the exact elevation for the waypoint pre programmed. Wypt elevation is not however a player in CCIP. As to using Auto with the wrong elevation... not a big deal ... the diamond obviously wont be on the actual TGT so refine the designation in the HUD ... as soon as you stop slewing AGR takes a range sample and uses that for the calculation. If you didnt have AGR working then yes it would be an issue. The issue here is why is the DIL line and CCIP + leaning over after 30 mins flight time in nil wind? This only happens if you are not using AINS. If in the ME you set the date to pre GPS times (e.g. 1985) you only have POS INS (INS in NAV rather than IFA) . Flying the same mission with a date say 2020 with POS AINS you dont have the issue.

In the 1985 type Hornet with non RLG type INS and without GPS an IFA is a big deal.

Looking further. Noted Nil wind then had a look at the DIL line on 4 different headings all around 90 degrees apart (Standard diagnostic thing in the last century on non GPS aircraft). Heading East or West DIL is is normal and vertically below the VV. But on Northerly and southerly headings it always leans towards the EAST !! ... Why ? If there was some unkown wind the DIL would be displaced downwind regardless of heading. In balanced flight nil wind DIL should be vertically under the VV. When I bombed with CCIP on the target weapon impacts were WEST of the CCIP cross. Take Off point Batumi, Tgt Novorssiysk so a fairly large change in Latitude .. about 3 degrees worth. Dist about 252nm. Is this some Earth transport error being reflected in a false vertical ? Update: Tested again over 250nm East West track no latitude change .... same issue with CCIP DIL and bomb impacts. Then reflew the first mission with POSAINS no issue DIL was good weapon impacts good.

Ok just had a look at INS drift over 30 mins POS INS only. after 30 mins the Drift was as shown in attached screen shot. So not to bad. However CCIP release resulted in bombs impact as shown by the X. I then attempted another CCIP release on a heading 90 degrees from the first ... same issue. Then landed GS showed 0 when parked. So something is very wrong imo. The Drift exhibited(though I consider ok) should not have resulted in the CCIP bomb errors seen. Doing an IFA is a not in real world a real option just to improve things ... it wont your original alignment will always be way better than any IFA. IFA is a last chance type thing to try and get something back after after say an INS crash etc. A vel update using PVU might be a thought .... though again should not be required.... and it doesn't look like its implemented. Either way the CCIP release impact errors seen after just 30 mins of flight are completely wrong. I tried an Auto release but need to try again after refing the designation to see where the bombs go. Anyway its a major issue imo ... good pick up Svend.