Kercheiz Posted July 1, 2020 Share Posted July 1, 2020 When following a tanker locked on radar, I noticed the relative speed displayed on the HUD is very different in TWS and STT, by about 50kts. And it seems the TWS one is wrong, because I could maintain -20 displayed while the distance decreased, and relative speed in STT was +30. Link to comment Share on other sites More sharing options...
Steph21 Posted July 1, 2020 Share Posted July 1, 2020 Indeed, i noticed a couple of times that relative speed was displaying negative value whereas i was closing in on a target. Would be great if you could add a track showing the issue for the devs. Link to comment Share on other sites More sharing options...
Kercheiz Posted July 1, 2020 Author Share Posted July 1, 2020 Here is a screenshot where I switch from TWS to STT within a few seconds. This time TWS relative speed is off by 230kts... And here is the track file radar-speed-bug.trk Link to comment Share on other sites More sharing options...
jojo Posted July 2, 2020 Share Posted July 2, 2020 Here is a screenshot where I switch from TWS to STT within a few seconds. This time TWS relative speed is off by 230kts... [ATTACH]241425[/ATTACH] And here is the track file [ATTACH]241424[/ATTACH] The bug is that radar should have switched automatically to STT by this range. :music_whistling: Mirage fanatic ! I7-7700K/ MSI RTX3080/ RAM 64 Go/ SSD / TM Hornet stick-Virpil WarBRD + Virpil CM3 Throttle + MFG Crosswind + Reverb G2. Flickr gallery: https://www.flickr.com/gp/71068385@N02/728Hbi Link to comment Share on other sites More sharing options...
ZHeN Posted July 2, 2020 Share Posted July 2, 2020 The bug is that radar should have switched automatically to STT by this range. :music_whistling: what's the minimum range radar would've stayed in TWS if it hadn't been bugged ? [sIGPIC][/sIGPIC] Link to comment Share on other sites More sharing options...
pierrewind Posted September 20, 2020 Share Posted September 20, 2020 Hi razbam! When a target is locked in PID, the delta V can be wrong (most importantly showing negative closure speed when actually closing on target). In PIC the issue seems to go away. Thanks Pierremirage 200 PID speed bug.trk Link to comment Share on other sites More sharing options...
RAZBAM_ELMO Posted September 25, 2020 Share Posted September 25, 2020 Hi razbam! When a target is locked in PID, the delta V can be wrong (most importantly showing negative closure speed when actually closing on target). In PIC the issue seems to go away. Thanks Pierre Hi Pierre, can you confirm this is still present in the latest OB update from 23/09/2020? Know and use all the capabilities in your airplane. If you don't, sooner or later, some guy who does use them all will kick your ass. — Dave 'Preacher' Pace, USN. Link to comment Share on other sites More sharing options...
Kercheiz Posted September 26, 2020 Author Share Posted September 26, 2020 Same as https://forums.eagle.ru/showthread.php?t=279820 I will check if it happens again Link to comment Share on other sites More sharing options...
pierrewind Posted September 26, 2020 Share Posted September 26, 2020 This bug is still active.mirage 200 PID speed bug.trk Link to comment Share on other sites More sharing options...
RAZBAM_ELMO Posted September 26, 2020 Share Posted September 26, 2020 This bug is still active. This trk is from the new OB version? Know and use all the capabilities in your airplane. If you don't, sooner or later, some guy who does use them all will kick your ass. — Dave 'Preacher' Pace, USN. Link to comment Share on other sites More sharing options...
pierrewind Posted September 26, 2020 Share Posted September 26, 2020 Affirm Link to comment Share on other sites More sharing options...
Rayak Posted September 26, 2020 Share Posted September 26, 2020 Isn't this behaviour an actual shortcoming of PID rather than a bug ? The delay between 2 sweeps inducing an error on velocity Link to comment Share on other sites More sharing options...
pierrewind Posted September 26, 2020 Share Posted September 26, 2020 Not as I understand a radar. Radar goes first swipe, and it give a relative distance to target. Then , when it crosses the target again on a swipe (not necessarily the first after) it will get a new distance. Then we do (D1-D2)/Dt and we get the relative speed! To have the best refresh rate, then you get to play with bars and azimut or STT/PIC. Link to comment Share on other sites More sharing options...
Rayak Posted September 27, 2020 Share Posted September 27, 2020 I would rather say that the radar deduces the velocity from the doppler shift rather than a mean value. I'm really not an expert of radar tech but inacurracy seems a logical drawback of PID scan Link to comment Share on other sites More sharing options...
pierrewind Posted September 27, 2020 Share Posted September 27, 2020 (edited) Well, when we say doppler radar, it is in fact pulse-doppler. This combination allows to obtain more information in a single pass. (A pulse radar wouldn't be as complete, though the pulse-doppler also has limitations). There is 0 reason for this inacuracy. The radar can obtain the relative target speed via the doppler shift. or via the distance shift between the two passes. The two methods are very accruate! The pure doppler radar is used on road radars... to my knowledge it is precise to less than 5% and will not show speed as if you're running backwards... https://en.wikipedia.org/wiki/Pulse-Doppler_radar Edited September 27, 2020 by pierrewind Link to comment Share on other sites More sharing options...
Kercheiz Posted October 20, 2020 Author Share Posted October 20, 2020 The bug is that radar should have switched automatically to STT by this range. :music_whistling: Do you have more info about this? Is this based on your knowledge of the real aircraft or past module behavior? Because it's behaving like that for a while. Link to comment Share on other sites More sharing options...
jojo Posted October 20, 2020 Share Posted October 20, 2020 Do you have more info about this? Is this based on your knowledge of the real aircraft or past module behavior? Because it's behaving like that for a while. I did ask to a pilot. No it never worked in game. Mirage fanatic ! I7-7700K/ MSI RTX3080/ RAM 64 Go/ SSD / TM Hornet stick-Virpil WarBRD + Virpil CM3 Throttle + MFG Crosswind + Reverb G2. Flickr gallery: https://www.flickr.com/gp/71068385@N02/728Hbi Link to comment Share on other sites More sharing options...
RAZBAM_ELMO Posted October 25, 2020 Share Posted October 25, 2020 Our SME is away for the week so will be unable to check on this for that time. @jojo this pilot is he active AdA? Perhaps if he knows so much we can talk to him internally and verify this information. Know and use all the capabilities in your airplane. If you don't, sooner or later, some guy who does use them all will kick your ass. — Dave 'Preacher' Pace, USN. Link to comment Share on other sites More sharing options...
RAZBAM_ELMO Posted January 13, 2021 Share Posted January 13, 2021 Bump, confirmed closer speed is negative in PID whereas it is positive in PIC Know and use all the capabilities in your airplane. If you don't, sooner or later, some guy who does use them all will kick your ass. — Dave 'Preacher' Pace, USN. Link to comment Share on other sites More sharing options...
myHelljumper Posted June 23, 2021 Share Posted June 23, 2021 Hi, this issue should be fixed with the ongoing AA radar update. No dates yet because a lot of work still needs to be done. Thanks Helljumper - M2000C Guru Helljumper's Youtube https://www.youtube.com/channel/UCK3rTjezLUxPbWHvJJ3W2fA Link to comment Share on other sites More sharing options...
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