Can't maintain altitude

[klm251 62]

Hey all.This is a problem i have seen before and i have asked about it as well.Somehow my 744X can't maintain it's altitude i have disabled thermal effects from the settings menu wich should solve the problem but it dusn't.I have made a video so maybe any of you have a clue what is causing this

http://www.youtube.com/watch?v=QY2qByYjZCo

[thebigmanwiththeplan 0]

hello i had a similar problem. FIrst load a cessna shut it down then end the flight after that load pmdg.

[des182001 1]

I'm going to take a stab at this.... In the video your EICAS is showing CON meaning that you have maximum continuous thrust engaged. MAX CON is used when you have a single engine failure at high gross weights, which by the looks of things all of your engines are fine. It should be in cruise mode at that point (CRZ). It looks like the airplane is trying to maintain your cruise speed with maximum continuous thrust. If it does it again go to the thrust limit page in the FMC and select the lsk for CRZ and see if it corrects the problem.

[Turbine777 13]

I concur with Dan. Not sure how you got to that thrust setting but you were having the balloon effect where others see the S-turns. Even with CON though it should still maintain alt but my guess is that you had a major TAT shift or Baro shift, set to CON to maintain alt (which is what I had to do before I got a registered FSUIPC). Or similar, where you hit one of those spots but CG got out of whack and it kept over correcting itself trying to gently level back out.Also, were you flying above the recommended Alt in the FMC?

[klm251 62]

The reason it was on con was because of a change in wind everytime the wind changes in a tailwind my speed drops depanding how much kts sometimes significantly i use con to get back to the speed wich is programmed in the fmc when i flew with the FS9 744 it didn't had this problem this isn't also the first time it happend before i got the tip to disable thermal effects in the options menu under weather but it didn't solve it this time i also wasn't flying above the selected altitude in the fmc it was programmed at FL320 i even descended to FL300 to see that it got any better no result there it just seems that vnaf isn't able to hold the airplanes pitch i will try what shaz told and let you ppl knowThanks

[Turbine777 13]

Yes, it didn't happen in FS9 because it is a weather issue with FSX... Try everything you can, by all means. Then when you want to actually fix the issue, get a registered FSUIPC and ask someone for their settings.

[des182001 1]

get a registered FSUIPC and ask someone for their settings.

That's going to be your only option if it's wind shifting issues.

[NickolasSWE 0]

I have a same problem and I don't think the reason that it can't maintain the altitude is because something with the balance or something not a wind shifting eaiter, I already test with the clear weather on FSX standard weather, still it can not maintain. When I cruising I have the trust limit on CRZ and everything of the setting is correct, but I still not maintain, and the problem appear when the aircraft is heavy loaded so I think is might be that the rouder can not hold.....but anyway please help......!!!!

[G-CIVA 62]

This forum is littered with hundreds of posts on this subject.You need to 'squeeze' weather inputs into FS to slow down the rate of change in wind speed & direction, & slow down the rate of change of temperature & pressure.A fully registered version of FSUIPC is the way ahead...by purchasing you are also giving a little back to a man who has done so much for the FS community.Always set the ZFW via the PMDG Load Manager...if you try to use another method (TOPCAT or native FS weight & balance) you will screw up the load stations within the .cfg file.For best results set up a scenario that you load when starting FS...the default basic cessna parked in a position (gate & ARPT) of your choice with clear WX. Fully powered down.You may wish to fully disconnect your Yoke/Pedal/Throttle from FS & fully configure via FSUIPC...this prevents background noise from your controllers interfering with the PMDG control surfaces (this includes items like the brakes).Load the PMDG from this saved scenario...once it has loaded choose a cockpit scenario from the PMDG drop down menu...let that load before commencing your preflight.Always load fuel via the PMDG drop down menu.If you decide to swap 744 variants or even use a different aircraft close FS & restart...if you do otherwise you may get issues.Finally, fly the aircraft within its performance parameters...observe the MAX FL figure on the VNAV CRZ Page & do not exceed.Works for me every time & I get flawless results

[Cras 6]

I use TOPCAT to load the PMDG 744 exclusively, but I do use the PMDG drop down menu for fuel, this is a must, there is no way around it. I have never seen a load issue with TOPCAT, I always get the # of pax from FSPassengers, then use vRoute to figure my route and fuel needs. Load the data up into TOPCAT, and always get good results. I have gotten knocked out of the air by winds, but there are new verisons of ASE that really do eliminate this, and wind smoothing will do a great job at this as well. I also say a big +1 on the temp smoothing on FSUIPC as well. Before using this occasionally would see stupid temps in the air, like I was seeing ground temps all the way up to 35000 feet in the air, this of course sucks tons of performance out of the engines, which makes it near impossible to maintain high altitude and high speed in cruise.

[G-CIVA 62]

That's fine as long as you are sure that TOPCAT is correctly loading the load stations that exisit within the .cfg file.If you have loaded the ZFW in the PMDG Load Manager (many months ago perhaps?) & did not use the tri-class PAX configuration & are now using an aircraft file within TOPCAT that does have a multi PAX configuration you will be loading the aircraft incorrectly. Can you be absolutely sure TOPCAT has loaded all of the load stations in the .cfg file correctly?That's why you are better off using the PMDG Load Manager...thats why they ship it as an integral part of the addon...which is why I believe that the advice we give to newer pilots here is to use the PMDG Load Manager until they are confident with what they are doing.I understand your strive for realism using FS passengers, but the actual PAX/Bag/Tin numbers are really irrelevant in the virtual world.The important number is the ZFW for fuel/flight planning purposes.