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Guest roastbeef

Strange behaviour, when flying in very high QNH

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Guest roastbeef

Hello people :)I just landed safely after having some serious issue during approach. My correspondence with ATC looked like that:ATC: CSA723, turn left HDG330, descent 4000ft, QNH1038 Hpa... (TL at LKPR is 5000FT)CSA723: Descending 4000ft..after cca 1 minute I leveled at 4000ft on QNH1038ATC: CSA723, please report altitudeCSA723: Altitude 4000 FTATC: Please confirm QNH 1038 HPaCSA723: QNH1038 hpaATC: I have you at 3200ftCSA723: Im at 4000 according to my instrumentsATC: never mind, maintain present altitude until G/S capturedI checked the FS via shift+Y (when you swith coordinates, speed, FPS, etc...) Altitude said 3200FT...Can anyone tell me, what has happend? 772-LRRostaP.S. No failures setting...

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Guest roastbeef

So, I just talk to couple VATSIM ATCs. They all agree, that generaly people flying PSS planes have troubles in very high QNH... 777,320,330,.... Looks like, there is some glitch in PSS altimeters... What also happend yesterday is that, on the ground at LKPR it

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Guest Raphouille

Hello, this experience could be related to more "real world" factsIf I'm not wrong, real life Secondary radars reads the altitude sent by your transponder encoder, wich will always be the pressure altitude (=Flight Level)1Mb = approx 28feetQNH 1038QNE 1013diff = 25Mb = 700 feet, wich is the approximative difference between your altimeter reading and the altitude read by ATC.QNH above 1013 -> 4000ft is lower than FL040QNH = 1013 -> 4000ft = FL040QNH below 1013 -> 4000ft is higher than FL040Best regards, Rapha

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Guest roastbeef

So could you please tell me exactly, what have I done wrong? Thanks Rosta

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Guest Raphouille

>So could you please tell me exactly, what have I done wrong?>Nothing at all ! :-coolYou did it the right way!Maybe the controller wasn't aware of this... and have notified the difference between FL and altitude because these high pressure areas do not happens very often. Have fun in the air,Rapha

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Guest Raphouille

:-hmmm so, it could be related to an issue with the PSS777, but I've never experienced this "bug".Regards, Rapha

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Guest NormanB

Ive not seen this and control and fly on VATSIM for quite literally thousands of hours.

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Although encoding altimeters operate on the basis of standard pressure (so that you can't be cheeky and fiddle with the kollsman setting!!), irl what ATC see on their displays should be corrected for QNH. I wonder if VATSIM replicates that?Jeff

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Guest roastbeef

Well, I talked to Czech VATSIM ATCs (only a few people, but very very experienced) and they all said the same - in very high QNH (around 1040hpa) PSS planes have problems... We had QNH like this for past few days in LKAA, so It was clear to see... Or, It can be connected somehow to FSinn/Squawkbox... I would put a link to forum, where we also talked about it, bud it

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