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Guest Daniel Pimentel

A320 stalling on initial climb?

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I am probably making a mistake here... But I'm not sure where. In this case if happened using the iFDG A320, but it happens also with the PSS models. I enter the weights as they're displayed on the FS9 fuel and payload section (yes, I check display fuel as weight so I enter it in lbs)... And I enter the empty weight there as my ZFW. However, right after liftoff, when the AP takes over to climb it does so VERY steeply, and stalls the aircraft.I am sure it's probably my bad, but I'm not sure what exactly I'm doing wrong. Any suggestions appreciated.Daniel.http://www.precisionmanuals.com/images/forum/ng_driver.jpgMember of SJU Photography. [A HREF=http://www.jetphotos.net/showphotos.php?userid=9004]Click Here[/A] to view my aircraft photos at JetPhotos.Net!The official psychotic AA painter. :)

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Whether you are flying the pure PSS aircraft or the merged ifdg/PSS variant one thing you have to watch very carefully is your speed on initial climb. You must stabilise at V2+10 and not shoot through it to a faster speed - at least not by much. If you do, as soon as you engage the autopilot the nose will pitch up dramatically as the computers try to bring the speed back to V2+10. One way to assist with this is to set the pitch trim to -2.0UP using the End key.

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John:Will do.Rob:Thanks for the tip. The question is, how can I stabilize at that speed if I put the throttles on T/O config for takeoff? They keep the thrust at max, I think. Unless I'm supposed to change the throttles to CLB the moment I shoot off the ground? I am just not sure what I should do with the throttle to maintain that speed. Again, thanks for the tip.Daniel P.http://www.precisionmanuals.com/images/forum/ng_driver.jpgMember of SJU Photography. [A HREF=http://www.jetphotos.net/showphotos.php?userid=9004]Click Here[/A] to view my aircraft photos at JetPhotos.Net!The official psychotic AA painter. :)

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John:Look at this. I followed the tutorial... Look what happened. This is doing the FS2k4 test flight. The aircraft turned very abruptly to the opposite side I told it to turn (since it stalled as soon as I engaged AP and it nosed up as you see here). This happened in around what, 20-25 secs? Any help appreciated. I'm probably doing something wrong... I just don't really know what.http://forums.avsim.net/user_files/85119.jpghttp://www.precisionmanuals.com/images/forum/ng_driver.jpgMember of SJU Photography. [A HREF=http://www.jetphotos.net/showphotos.php?userid=9004]Click Here[/A] to view my aircraft photos at JetPhotos.Net!The official psychotic AA painter. :)

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You do not do anything with the thrust levers until the LVR CLB memo in white on the PFD comes up and you move them back to the CLB gate.To maintain V2+10 you must watch the magenta triangle on the speed tape of the PFD over on the far left. This is pointing to V2+10 (until your takeoff roll speed increases you'll see v2+10 shown in magenta figures above the speed tape). You should adjust your pitch so that the speed is as close as possible to that magenta triangle. Inevitably you will be slightly above the speed but use pitch to control this. You might well find that you need to pitch to as much as 20 degrees but don't worry about this. As I said in the earlier post, it is important that you are close as possble to V2+10 when you select the a/p. Just one caveat to that is that if you wait and don't engage a/p until you are further into the climb, have retracted flaps and passed green dot speed then when you select a/p you shouldn't experience the pitch up even if you went beyond v2+10. But it's good practice to try to hold V2+10 manually for as long as possible and occasionally to delay engaging the a/p until you are well into the SID.One thing I have noticed is that the iFDG model merged with the PSS panel seem to be slightly better at stabilising at V2+10 than the pure PSS aircraft.

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First off, the ZFW is not the Empty Weight.zero fuel weight is exactly as it says. Everything but the fuel.This thus also includes the Payload.simple rule: add the 1st 2 numbers in the payload/fuel dialog together and enter that in the FMGC.I remember having a similar problem but once i installed that Panel.cfg update(avail. on this forum) it all went perfect again.Greetings

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Looking at the screenshot the V2+10 seems VERY low. Something wrong there with the weights and Vspeeds.

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Greetings Dan & allOne of the things that I wanted to point out, Lenny has already covered it. ZFW = Zero Fuel Weight, which is Aircraft operational empty weight plus Payload. The next thing that it asks for is Block Fuel, meaning fuel weight before push-back and engine start. Double check that the figure that's shown next to TOW in thousands, matches what is shown in FS-9 Gross weight rounded to the nearest tousand.Operational empty weight will vary (in real life) from airline to airline it will include crew oil, every thing that the aircraft needs to operate except for fuel and payload. The empty weight shown in FS-9 is just what your airline is using.I would follow Rob's suggestion to hand fly this bird in the early stages. Even when you're ready to engage the A/P I would still retain some control over speed. (Pull the knob, and set your speed) then do a double key punch on the minus (-) key on the keypad. This gives you CL mode and follows (or should) your set-up speed. Climb to altitude I NEVER turn this thing loose to do it's own climb rate. I've seen it hit 5300 plus FPM, so I set the VS dial to around 1600 FPM or so. Most major USA airports will intial clear jets to 5,000 ft and prop aircraft to 3,000 ft. Then take you up from there within ten minutes. A standard clearance that most of us could repeat in our sleep was (example) "Eastern fifty one climb & maintain five thousand expect Flight level three one zero one zero minutes after departure, contact departue control one thirty five point niner, swquak 4631"BTW most of my PSS Airbus experience has been in the A340, I've never been able to get the A320 off the ground.Bill Martin

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Guys:Thanks a lot. I will be trying this again, keeping what I've read here in mind. I'll report what happens. Thanks!Daniel P.http://www.precisionmanuals.com/images/forum/ng_driver.jpgMember of SJU Photography. [A HREF=http://www.jetphotos.net/showphotos.php?userid=9004]Click Here[/A] to view my aircraft photos at JetPhotos.Net!The official psychotic AA painter. :)

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