Hello everyone
I have a problem, when I select the arm button to obtain the chosen altitude, it stops with an offset of a few hundred feet from the chosen altitude. Is it me who made a mistake?
Jack
Is your altimeter set to local pressure? Does pressing the âBâ key sort it?
Here it is set to 30.24 as ATC has indicated to me, but the problem appears all along a trip with different pressures whatever I choose. I have no mods in my community directory.
I took another plane and then reloaded the M20R and now it seems to be working normally. It is very confusing. 
very odd, been using the m20r recently, havenât run across that issue.
i do hit the B key a couple of times prior to taking off, so not sure if that helps to prevent the issue.
Iâll try if it doesnât work again. Thanks in the meantime.
Iâve seen this happen. Not sure if itâs meant to be like this or just MSFS is being MSFS.
Seems to be an issue when manually selecting alt pressure. When you press B it works as expected, but sets it to whatever the local pressure is in MSFS weather.
Submit a bug report to Carenado pls.
I have noticed this bug yesterday aswell. The in cockpit steam gauge does not set the pressure for the âwhole planeâ and just changes what is displayed by that gauge which means that the autopilot still uses a pressure of 29.92 mmHg and the offset you are seeing is exactly the deviation between the set pressure on the gauge and âstandard pressureâ as FreedFlyer97231 and g1wkr noted pressing âBâ will resolve this issue as it sets the âoverallâ pressure to your local pressure. But you will have to keep pressing it every time there is a change in pressure otherwise it will start deviating again.
Itâs a âthe way MSFS worksâ thing, which in fact models real life; and, yesterday, I just covered why this issue is happening hereâŠ
https://forums.flightsimulator.com/t/mooney-m20r-basic-information/277840/1223?u=flyingscool5650
One thing to note in the Asobo KAP-140, which is what the Carenado is using, there is an option to independently set the barometric pressure for the AP for use in the flight levels since the B Key sets it to Indicated altitude, and changing the Altimeter barometric pressure to pressure altitude does not change the Autopilot Barometric altitude. I forget what the button combinations are and Iâm at work, but itâs in there.
Hi there. I reported the bug to carenado before arround 1 month before. Hope they will fix it soon.
Who are you responding too? If youâre responding to me, Iâm not the user who reported the issue, but, as far as I can tell from the description of the issue they posted, this is not a bug, itâs the way MSFS, and a real plane, would work. The AP is not normally tied to the Altimeter to change the barometric pressure, the pilot has to do that himself. As I noted, there is an option to tie it to the Altimeter, but, as I understand, not many order this option.
Then again, perhaps it is a bug and not tied to the barometric pressure, and itâs just going to the wrong altitude?
I have never seen this problem and I fly the Mooney all the time I hit the B key, which sets the altimeter to the correct setting, and if I want to climb to 4,000 feet, the AP levels at exactly 4,000 feet. I have never seen a difference in the altitude that the AP levels off at, and what I have dialed in on the AP altitude adjustment,
Exactly. But those who were unaware of the B Key would have issues. As theyâd set their altimeter, and then the AP would go to the wrong altitude. This is not a bug. This is how it works, as I stated in my post.
Also, as I stated, if you hit the B-Key, and then change the Altimeter to Pressure Altitude when youâre above 18,000 ft, your only recourse is to figure out the buttons to also change the AP barometer to Pressure Altitude.
Then @swisszulu posted he submitted a bug, and Carenado told him they would fix it. The above is not a bug, and Carenado canât fix it, unless they link the AP to Baro 1, that would fix it. And there is an option you can purchase for the real AP that does this, too. But it means Carenado has to rewrite the AP, and then would have to parrot any changes Asobo makes to their AP, which Iâm pretty sure is what Carenado is using today (the KAP-140 from Asobo for the code). I might be wrong on that point, I 'll check when I get home.
Edit: Nope, Iâm wrong⊠They wrote their own AP, and we donât have access to it. But, everything else is true. So, they can fix it to work with the B key by linking it to Baro:1
@FlyingsCool5650 Thanks for your answer. Sorry a adressed my comment to all. Not special to any one.
What I meant with my problem is, when I fly âFlightLevelâ with standard preassure 1013/2992 the AP will choose the selected altitude with the real outside preassure. Mostly this is different. Then I fly above or below some 100 feets at the selected altitude. I thougt this is just happened in the Mooney. But I tried it now on other aircrafts. Its the same. So its a MSFS issue and not one of the M20R. Sorry for messing this up.
I have no problem with the B button.
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And my post above explains exactly why this happens. Itâs not necessarily a bug. Itâs the way the real plane works, too. The AP and your altimeter are not normally linked. You have to set both gauges to the correct Barometric pressure (either indicated or pressure altitude, whichever is required).
Using the B key sets both to indicated altitude. There are actually a couple other scenarios that would make them get out of sync as well. Itâs because, unless you set the barometric pressure setting of the AP, itâs going to use whatever it has been set to. To correct for indicated altitude is easy, hit the B key, that will set both guages to indicated Altitude. When I get a chance, Iâll figure out how to set the AP to Pressure Altitude. Itâs in the manual for the actual AP.
Carenado can fix it by setting the AP to read from Baro:1 instead of Baro:2. Baro:1 is normally the register the Altimeter sets when you set the gauge to indicated or pressure altitude (or whatever), and normally the AP uses Baro:2. Setting the AP to use Baro:1 would be different from the traditional programming methods used in FS, so theyâd have to do it right or they could break the functionality of both gauges.
Nobody has a problem using the B key.