"Altimeter not set correctly", autopilot questions

Hi. A couple of questions here :

One is about this "altimeter is not set correctly. Press B ..." message that keeps popping up at random times. I almost always start at the same airport but the message sometimes doesn't show up at all while other times it pops up as soon as I start the game (plane still on the runway). Why is that? Is this like a random thing by the game? The other half of the problem is that pressing "B" is supposed to set the altimeter automatically but no matter how many times I press B the message just keeps popping up every few seconds and it's really pissing me off. So, why is this?

The other question is about the autopilot in some of the free Airbus add-on planes (A330's specifically). I set the altitude and climb rate at/after takeoff -but nothing else as I want to be able to steer the plane myself- and hit the autopilot but then I'm unable to steer the plane, just as if the heading were set too. So basically autopilot will take control of the heading of the plane too -it will just keep flying straight- even if I don't have any destination set and "Loc" is off. I just can't figure out what the problem is. In my A319's add-ons, no such problem. I set the altitude and climb rate and when I engage the autopilot I can steer the plane myself. What's up with the A330s' autopilot ?

Thank you.

First answer, it depends on your weather setting. If the weather around is constantly changing, affecting the local pressure, you will see that message, it is not random. Since you say it is repeating, check if your actual altimeter pressure is changing by pressing "B" or not.

Second answer, it is kind of a bug with FSX. But, nothing to worry, can be easily rectified. Once you activate the autopilot, toggle the heading mode on and off. Once it is back at the off position, you will be able to control the plane manually.

I created a gauge for you that basically just constantly resets the Altimeter.

Srangely the gauge does not affect the standby-altimeter, to reset that you would still need to press the >b

But using my gauge, no more "300 above assigned altitude, and no more steep climbs and descents when the weather changes.

Enjoy!

https://www.flightsim.com/vbfs/showthread.php?299584-Barometer-Reset-gauge

Thank you all for the replies and the tips. I use Rex OD and the weather (in the game) where I am (on the West coast) is always cloudy. So I don't know if that causes the altimeter to keep changing (in the real world and in the game). Yes I tried looking at the altimeter reading (on the instrument) and noticed it did change after pressing B but only for the first time I pressed it but I never checked to see if the reading changed again causing the message to keep popping up. I'll check that next time I play the game.

I know I can turn off "flying tips" as suggested by thefrog, but if I don't have the altimeter set correctly won't that affect the true altitude of the plane and won't that mess things up when in autopilot?

I know I can turn off "flying tips" as suggested by thefrog, but if I don't have the altimeter set correctly won't that affect the true altitude of the plane and won't that mess things up when in autopilot?

It won't mess anything but may result in separation issue because of you being at the wrong level.

Trancer365,

If you're using "real weather", either from within FSX or a weather add on, the pressure setting does change. This happens in the real world.

Pressing "B" on some add on aircraft doesn't work. You have to physically adjust the pressure setting on each altimeter. You can check the current weather setting by listening in on the airfields ATIS or AWIS, or the weather page in the menu.

As for your second question. Most autopilot installations control both your elevator and airleron (and rudder if you're lucky). By connecting the autopilot, the default modes are normally wings level and altitude hold. Hence why you now no longer have any manual control of the aircraft. More sophisticated aircraft (like the A320/B737), have much more advanced autopilot systems . Unfortunately the only solution really is to have a read of the aircrafts manual.

Trail and error mate. That's the beauty of simulators. You can practise and make mistakes till you get it sorted ;)

This might also depend on how sophisticated the downloaded aircraft really is. Those that only rely on the built-in FSX autopilot logic will work pretty much like you expect (=like the default airplanes do). But if the developer chose to be more realisitc with the systens, you end up having to deal with managed and selected autopilot modes and the varying degrees of computer control over the aircraft. Airbus computers usually prevent you from doing things that they consider dangerous or inappropriate. Then again, a massive amount of programming is needed to implement the Airbus systems halfway correctly in FSX, and I think very few developers went all the way.

So you are not only fighting the real-world oddities of an airplane model, but especially the developer's interpretation of them - that might be completely different between two downloaded models made by different people. As a consequence "B" might not work, or the autopilot behaves in unexpected ways.

btw. altimeter: you could superimpose the flight data with "Shift-Z" and read the actual altitude from there. Compare it to what you see on your altimiter. If "B" does't adjust the barometric correctly, then just fly a couple of hundred feet higher or lower until ATC stops complaining. Or adjust it directly on the altimeter gauge as suggested above. I am flying with FS Captain a lot, so I have to use the first method - otherwise FSC would "ding" me for not changing the baro ref when passing the (correct) transition altitude for the airfield.

Yes trancer356.

Each time the weather changes, so does the Altimeter setting.

That means that if you are flying on autopilot, the plane will make a steep climb, and then a steep descent after you press >B<.>

(or the other way around, depending on how the weather changes.)

That is why I created that gauge for you. It resets the Altimeter as soon as the weather changes. So no steep climbs. And no annoying messages from ATC.

See the link I gave in my previous post. It explains how to make and install the gauge.

Trancer 365,

I'm sorry, there was something wrong with the gauge I created.

It would not allow keypresses such as: "shift+e, then press 2" for opening cargo door.

Therefore I have decided to withdraw the gauge. At least for now.

I'll keep thinking about a solution... but nothing in the near future I fear.

il.

Ok. Thank you again guys for the replies and for explaining things. I didn't realize different addon planes (free ones) can vary -even within the same model- in the way they operate ... I guess depending on how realistic the creator want them to act.

Anyway, just tried toggling the heading button on and off as suggested by rishabk and then I was able to steer the plane after that. Thanks. So I'm guessing it is some kind of a bug.

As for the altimeter message, it didn't come on at all this time I played fsx.

Thanks again guys for the help, and thanks il88pp for the link anyway. No worries.

So I'm guessing it is some kind of a bug.

Apparently it isn't a bug as I previously called it. As lnuss mentioned, the autopilot when engaged activates the wing leveler too.

Anyway, now you know how to disable it.

This behavior can be defeated with an aircraft.cfg edit.

In the [Autopilot] section look for...

default_bank_mode=

If it is not there, add it and set it to...

default_bank_mode=0

If it is missing, or is there and set to =1, the autopilot goes into Wing Level Hold upon autopilot activation.

Setting it to =0 (zero, not oh) will negate Wing Level Hold.

peace,

the Bean

Just to amplify what the great StringBean mentioned, not only is there the line default_bank_mode= that can hold wings level or heading set into the AP, depending on the number after the = sign, there is also default_pitch_mode=, which can hold the current pitch, the current attitude, or nothing. The two are frequently used together in the Autopilot section.

If you want neither of them to activate upon autopilot activation, they should both be present and set to 0 (zero, not oh, as mentioned). If the lines are not present, the default setting is Pitch Hold and Wing Leveler.

Check to make sure, if you want neither to activate, that both lines are present and set to 0. If they aren't add them in yourself. You can copy-n-paste them right from this post if you like, to prevent typo's (one of my major faults).

For more information on how the AP works and what the entries in it mean, you might want to take a look at THIS SITE. I find it very informative and useful.

I am not super expert at PID Controllers, which the AP is, and you have to be very careful, as the settings can be quite inter-related.

Hope all this babbling helps a little...

Pat☺