Why does my altitude suddenly jump a few hundred feet above and below the MCP set altitude during cruise when the baro is set to STD? As far as i can see winds are not changing velocity or direction (displayed on the ND) so where is this issue coming from?

 

 

As far as i can see winds are not changing velocity or direction

 

Wind isn't the driver of barometric pressure, though I'm assuming you're pointing this out to say that "it doesn't look like the weather is updating," or similar.

 

 

 

so where is this issue coming from?

 

Weather program updating the barometric pressure.

 

Just because it's standard doesn't mean it's immune to pressure changes, particularly when the sim unrealistically immediately updates them.  In the real world, the aircraft simply follows the pressure gradient, and no matter how closely spaced the bars are on the chart, there's a uniform transition because of the fluid nature of air.

 

You can minimize this using various weather programs, or through using FSUIPC's pressure smoothing.

 

Wind isn't the driver of barometric pressure, though I'm assuming you're pointing this out to say that "it doesn't look like the weather is updating," or similar.

 

I specifically chose to say "winds" because that is the only weather variable i can monitor from the cockpit. I don't know if the rest of the weather is changing or not. So yes in a way i meant it as "i have no indication that the weather is changing"!

 

Weather program updating the barometric pressure.

 

Just because it's standard doesn't mean it's immune to pressure changes, particularly when the sim unrealistically immediately updates them.  In the real world, the aircraft simply follows the pressure gradient, and no matter how closely spaced the bars are on the chart, there's a uniform transition because of the fluid nature of air.

 

You can minimize this using various weather programs, or through using FSUIPC's pressure smoothing.

 

I see. It's also causing issues during the climb because the airspeed will suddenly drop to below stall speed or way above overspeed. I have disabled turbulence effects in FSX in case that was the cause but it didn't solve it so you're right, it must be weather updating. 

 

Thanks, i'm still quite new to the addons scene so i do often overlook things that most of you guys probably hear a million times. I'm still having issues doing searches on this site for past topics, it seems the search function brings up a ton of irrelevant results first.

 

 

I see. It's also causing issues during the climb because the airspeed will suddenly drop to below stall speed or way above overspeed. I have disabled turbulence effects in FSX in case that was the cause but it didn't solve it so you're right, it must be weather updating.

 

Yeah, that definitely sounds like weather updates getting in the way of things.  Weather programs will help solve this (like ActiveSky and the others out there), though they tend to be yet another item to purchase.  I find them to be worth it, but I realize not everyone has an endless sim budget.

 

 

 

Thanks, i'm still quite new to the addons scene so i do often overlook things that most of you guys probably hear a million times. I'm still having issues doing searches on this site for past topics, it seems the search function brings up a ton of irrelevant results first.

 

You're welcome.  The search function on the site is hit or miss.  You really have to know what you're looking for in order for it to be particularly effective (the right terms, mostly), and part of that just comes with time, unfortunately.  I've gotten a couple Service Unavailable errors when trying to search for relevant topics for people recently, too.

 

Glad you at least tried the function, though!  Most don't!

Yeah, that definitely sounds like weather updates getting in the way of things.  Weather programs will help solve this (like ActiveSky and the others out there), though they tend to be yet another item to purchase.  I find them to be worth it, but I realize not everyone has an endless sim budget.

Thanks for the suggestion. I had one of those weather addons for FS9 (just made the jump to FSX a few weeks ago) so i'd never noticed the effects of not having one until now. I was planning on buying ASN for FSX anyway but it'll have to wait since i just blew the equivalent of $1800 in your currency on a PC to run the thing!  :lol:

In addition to weather updates and pressure channges your plane could be subject to updrafts and downdrafts. I use ASN and when I looks at a ASN Session Log there are a lot of these vertical winds that effect the plane.

 

Michael Cubine

Thanks for the suggestion. I had one of those weather addons for FS9 (just made the jump to FSX a few weeks ago) so i'd never noticed the effects of not having one until now. I was planning on buying ASN for FSX anyway but it'll have to wait since i just blew the equivalent of $1800 in your currency on a PC to run the thing! :lol:

There are free alternatives to use until you buy ASN. I use FSrealWX Lite which does a very good job at smoothing wind changes and presenting weather effects. You may find you don't need to buy a payware weather engine at all.

There are free alternatives to use until you buy ASN. I use FSrealWX Lite which does a very good job at smoothing wind changes and presenting weather effects. You may find you don't need to buy a payware weather engine at all.

 

Interesting, duly noted. I'll have a look at it.

 

In addition to weather updates and pressure channges your plane could be subject to updrafts and downdrafts. I use ASN and when I looks at a ASN Session Log there are a lot of these vertical winds that effect the plane.Michael Cubine

 

 

I must apologize for giving you incorrect information concerning ASN Session Logs. The updrafts and downdrafts are no longer shown in the log. It must have been AS2012 or ASE where I saw them. I feel cetain they are still present but they are not reported in ASN session Logs.

 

Michael Cubine